July 13, 2007
Nutrition Research Alert
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WEIGHT LOSS AND HEALTH OUTCOMES IN AFRICAN AMERICANS AND WHITES AFTER GASTRIC BYPASS SURGERY
EFFECT OF INCREASED DAIRY CONSUMPTION ON APPETITIVE RATINGS AND FOOD INTAKE
SIBUTRAMINE PLUS MEAL REPLACEMENT THERAPY FOR BODY WEIGHT LOSS AND MAINTENANCE IN OBESE PATIENTS
A GREEN TEA EXTRACT HIGH IN CATECHINS REDUCES BODY FAT AND CARDIOVASCULAR RISKS IN HUMANS
INTERVENTIONS TO PREVENT OR TREAT OBESITY IN PRESCHOOL CHILDREN: A REVIEW OF EVALUATED PROGRAMS
DOES A HIGH-PROTEIN DIET IMPROVE WEIGHT LOSS IN OVERWEIGHT AND OBESE CHILDREN?
PHYSICAL ACTIVITY LEVELS OF NORMAL-WEIGHT AND OVERWEIGHT GIRLS AND BOYS DURING PRIMARY SCHOOL RECESS
HERITABILITY OF HYPERPHAGIC EATING BEHAVIOR AND APPETITE-RELATED HORMONES AMONG HISPANIC CHILDREN
BMI; OBESITY; AND SICKNESS ABSENCE IN THE WHITEHALL II STUDY
EXERCISE EFFECT ON WEIGHT AND BODY FAT IN MEN AND WOMEN
PEDOMETER USE INCREASES PHYSICAL ACTIVITY OF LOW-INCOME WOMEN
THE EFFECT OF LARGE PORTION SIZES ON ENERGY INTAKE IS SUSTAINED FOR 11 DAYS
PARENT OVERWEIGHT PREDICTS DAUGHTERS’ INCREASE IN BMI AND DISINHIBITED OVEREATING FROM 5 TO 13 YEARS
BETWEEN MEAL CONSUMPTION OF SUGAR-SWEETENED BEVERAGES PLACES CHILDREN AT RISK OF BECOMING OVERWEIGHT
NUTRIENT INTAKE DECLINES DURING ADOLESCENCE IN HAWAII
NUTRIENT INTAKE IN CHILDREN WITH INTRACTABLE EPILEPSY
FRUITS AND VEGETABLES TAKEN FROM THE SCHOOL LUNCH LINE CAN PREDICT INTAKE
CHRONIC DISEASE AND DIET IN KOREAN AMERICANS
ASSESSING DIETARY INTAKE OF HISPANIC ADULTS WITH HIV
NUTRITION ASSESSMENT OF HIV PATIENTS IN GHANA
THE ECONOMIC COST OF HIGH-QUALITY DIETS
DEVELOPMENT OF A POLYAMINE DATABASE
ABDOMINAL FAT AND RISK OF CORONARY HEART DISEASE IN PATIENTS WITH PERIPHERAL ARTERIAL DISEASE
CAFFEINE INTAKE AND RISK OF HEART DISEASE MORTALITY IN OLDER PERSONS

WEIGHT LOSS AND HEALTH OUTCOMES IN AFRICAN AMERICANS AND WHITES AFTER GASTRIC BYPASS SURGERY

The incidence of obesity in the United States has reached epidemic proportions and is considered a significant public health threat. The National Health and Nutrition Examination Survey of 1999 to 2000 reported that 64.5% of adult Americans are overweight, with 30% considered obese. Despite increased medical awareness of obesity and a multitude of intervention programs, the prevalence of obesity has increased more than 75% during the past 25 years, with a mortality rate of 300,000 deaths annually. Obesity predisposes individuals to multiple comorbid conditions such as cardiovascular disease and type 2 diabetes. Although traditional diets can promote effective weight loss of 2 kg to 3 kg, intensive programs with long-term maintenance including diet, exercise, and behavioral change strategies can produce a 5% to 10% weight loss. This is generally ineffective for patients with Class III obesity (BMI > 40 kg/m2) and concurrent comorbid conditions. Gastric bypass (GBP) is known to be effective for severely obese patients, with subsequent improvements in cardiovascular and metabolic sequelae. The Roux-en-Y gastric bypass surgery is now recognized as the gold standard treatment for patients with Class III obesity with concurrent comorbid conditions. The Roux-en-Y gastric bypass promotes weight loss by limiting gastric volume and the rate of gastric emptying, with resultant early satiety. This procedure has demonstrated sustainable weight loss with manageable short- and long-term complications.

Studies have demonstrated significant improvements in cardiovascular risk factors and diabetes among white severely obese patients after GBP. Similar studies in other ethnic groups remain limited. This might be related to the less frequent use of bariatric surgery in minority populations. A small number of recent clinical studies suggest that severely obese African-American women lose less weight and show less improvement in blood pressure than severely obese white women after GBP. Although there might be metabolic differences between severely obese African Americans and whites, behavioral factors, such as dietary intake, might also account for differences in weight reduction. Clarifications of these differences are important for optimizing the postsurgical treatment of severely obese African Americans. Because of these racial disparities, it is important that weight loss interventions be targeted toward ethnic needs.

The researchers conducted the following study to compare weight loss between African American and white severely obese patients after GBP surgery in an urban obesity treatment referral center. They also examined differences in dietary intake and cardiovascular risk factors in this patient population before and after weight loss.

This was a retrospective database review of a sample of 84 adult patients (24 African-American and 60 white women and men) between the ages of 33 years and 53 years. All subjects had GBP surgery in 2001 at the Bariatric Surgery Program at Boston Medical Center in Boston, MA, and were followed for one year postoperatively. Patients were excluded if weight data were missing at baseline, 3 months, or 1 year after GBP. A total of 9 African Americans and 41 whites provided data at all three time-points and were included in the study. Differences in weight loss, diet, and cardiovascular risk factors were analyzed.

There were no differences in baseline characteristics between African Americans and whites. Mean weight loss for the entire sample was 36% ± 9%, with a range of 8% to 54% relative to initial body weight. Whites lost more weight (39% ± 8%) than African Americans (26% ± 10%). Dietary parameters, as well as improvements in blood pressure and lipid profiles, were similar in the two racial groups.

This study showed significant weight loss at 1 year among the entire sample after GBP. There were differences in weight loss between races, with African Americans losing 12% less weight compared with whites at 1 year after GBP; African Americans and whites lost a mean total of 44 kg and 61 kg at 1 year after surgery, respectively. These results are similar to those found in previous studies. The etiology for this difference in weight loss is still unclear; however, it has been suggested that genetic, environmental, behavioral, psychosocial, cultural, and metabolic differences contribute to this disparity. Another potential reason for this disparity might be the fact that there were more diabetics among the African-American group. As previously noted in published studies, obese diabetics tend to lose less weight, probably because of hypoglycemic episodes during hypocaloric dieting. However, this is an unlikely explanation in this study since most of the patients were not taking hypoglycemic medications postoperatively. Furthermore, separate analyses of the data did not reveal weight loss differences between the diabetics and nondiabetics in either racial.

This study observed a significant decrease in energy intake at 3 months and 1 year after GBP within each race. This is expected after GBP due to the reduced gastric pouch capacity. The findings of similar energy intake between races at each observed time-point after GBP suggest the possibility of metabolic differences between races. Other studies have found that African-American women seem to adapt to energy deficits more efficiently than white women; they require fewer calories for weight maintenance and have a reduced rate of weight loss on hypocaloric diets compared with white women.

In summary, the present data suggests that severely obese African Americans tend to lose less weight after GBP in comparison to whites. These differences in weight loss seem to be related to lower energy expenditure and not to dietary intake. However, despite smaller weight losses among African Americans, improvements in cardiovascular risk factors were similar between the two races.

W. Anderson, G. Greene, R. A. Forse, et al. Weight Loss and Health Outcomes in African Americans and Whites after Gastric Bypass Surgery. Obes Res; 15:1255-1463 (June 2007). [Correspondence: Nawfal W. Istfan, Section of Endocrinology, Diabetes and Nutrition, Boston Medical Center, and Boston University School of Medicine, 88 East Newton Street, Boston, MA 02118. E-mail: naistfan@bmc.org.]


EFFECT OF INCREASED DAIRY CONSUMPTION ON APPETITIVE RATINGS AND FOOD INTAKE

One potential intervention to aid weight management is to consume foods that offer a metabolic advantage. This may occur if a food is inefficiently absorbed and metabolized or increases sensations of fullness disproportionately to its energy contribution, and thereby moderates intake. Consequently, the actual impact of energy from the food is less than that predicted based on simple energy calculations. Regular consumption of such foods would be predicted to promote a modest weight loss, or accelerate weight loss on an energy-reduced diet. One group of foods that purportedly imparts a metabolic advantage is dairy products.

Epidemiologic data have revealed a small, but statistically significant, inverse relationship between body mass index (BMI) and calcium intake or dairy consumption. These observational studies are supported by some intervention studies, where increased dairy consumption resulted in weight loss or augmented weight loss on an energy-restricted diet. However, other studies report no effect of increased calcium or dairy consumption on body weight. A plausible physiologic basis for the positive observations is provided by cell studies that indicate calcium stimulates lipolysis in the adipocyte and increases fat oxidation. It was subsequently noted that, in humans, acute calcium intake is associated with increased fat oxidation over a 24-hour period, although other studies have failed to find such an effect. In addition, high calcium intake (1800 mg/d) increases excretion of fat through the feces because of the formation of calcium soaps.

In addition to these metabolic effects, the consumption of dairy products may increase sensations of fullness and elicit strong dietary compensation (that is, subsequent energy intake will be reduced by an amount equal to or greater than the amount of energy contained in the dairy food). Dairy products are rich sources of protein, a macronutrient with strong satiety properties. Release of the satiety hormone cholecystokinin may be especially strong after ingestion of caseinomacropeptide, a breakdown product of dairy proteins. However, other studies reported no effect of caseinomacropeptide on appetite.

Data from the aforementioned studies have led to the suggestion that consuming the recommended three portions of dairy each day (milk, yogurt, or cheese) may reduce the incidence of obesity by 85%. Because the effect of metabolic advantage on body weight is likely to be limited, increased dairy product consumption would need to elicit a substantial compensatory dietary response if energy balance was to be maintained or a negative energy balance induced. To date, there is a paucity of data detailing the effects of increased dairy consumption on appetite and overall energy intake. This study aimed to determine the effect of consuming one or three portions of dairy foods each day on energy intake and appetite. Because of potential sex differences in the sensitivity to cholecystokinin and, subsequently, subjective appetite sensations, men and women were analyzed separately. In addition, habitual low- or high-dairy consumers were recruited to determine whether habitual dairy intake affects the putative satiating properties of dairy product consumption.

Fifty-eight participants were required to eat one portion of dairy each day (low dairy) or three portions of dairy each day (high dairy) for 7 days. After a 7-day washout period, the opposite treatment condition was completed. Food intake and appetitive ratings were measured on each day of the treatment periods. The results found that during the high-dairy period, participants consumed 209 kcal/d more than during the low dairy period. There were no significant differences in subjective appetite ratings. Habitual dairy use did not influence either the appetitive or dietary findings.

The results from this short-term study cast doubt on a role for increased dairy product consumption in weight management. Consuming three portions of dairy products each day resulted in significantly increased energy intake compared with consuming a single dairy product each day. The increase in energy intake was greater in men than in women. Moreover, the increased dairy product intake did not elicit any changes in hunger or fullness sensations that would suggest a compensatory appetitive response for the additional calories.

In previous research, the weight lost during dairy or calcium intervention trials is no greater than would be predicted from the energy deficit incurred by the study protocol. During the study by Zemel et al., participants consuming the energy-restricted (-500 kcal/d) high-dairy diet lost 11.07 kg over a 24-week period. This amount is no more than would be expected to occur because of a 500 kcal/d energy deficit. Although the high-dairy and high-calcium groups lost more weight than the low calcium/dairy group, the reasons behind these cannot be ascertained without knowing how compliant each of the groups were to the energy-restricted diet.

Although this study reported higher energy intake after increased dairy consumption, the results must be placed in context. The short-term (7-day) nature of this study may not have provided enough time for compensatory responses to manifest. Leptin is released in proportion to body fat stores, and moderates sensitivity to peripheral satiety hormones. It may be that greater effects will be apparent with hypocaloric diets that independently promote weight loss. Indeed, one study suggested the strongest effects of dairy products on body weight occur under such conditions.

In conclusion, increasing dairy consumption from one to three portions each day led to increased energy intake. These data raise questions regarding the satiating efficiency of dairy products and the likelihood that they will elicit precise dietary compensation. Whether increased energy intake from dairy is offset by metabolic changes induced by components in these products needs further study because recommendations to increase dairy consumption to promote bone health may pose a challenge for energy balance.

J. Hollis, R. Mattes. Effect of Increased Dairy Consumption on Appetitive Ratings and Food Intake. Obes Res; 15:1520-1526 (June 2007). [Correspondence: Richard D. Mattes, Department of Foods and Nutrition, Purdue University, 212 Stone Hall, 700 W State Street, West Lafayette, IN 47907-2059. E-mail: mattes@purdue.edu.]


SIBUTRAMINE PLUS MEAL REPLACEMENT THERAPY FOR BODY WEIGHT LOSS AND MAINTENANCE IN OBESE PATIENTS

Clinical studies have suggested that moderate, sustained weight loss can reduce or eliminate surrogate markers of obesity-related disorders (such as type 2 diabetes, hypertension, and dyslipidemia). Unfortunately, long-term data show that most patients who lose weight regain their lost weight within 5 years, and that these disease-associated risk factors are re-established in patients with abnormal biomarkers [for example, increased fasting glucose, triglycerides or hemoglobin A1c or low high-density lipoprotein (HDL)-cholesterol] at the beginning of weight loss. There is substantial evidence to suggest that adherence to a low-calorie diet can be facilitated by using commercially produced meal-replacement products. The addition of pharmacotherapy to these diets may enhance compliance and increase efficacy. Sibutramine, a serotonin and norepinephrine re-uptake inhibitor, has effects on satiety and is indicated for the long-term management of obesity. It seems reasonable, therefore, to hypothesize that a combination therapy of sibutramine plus a low-calorie diet (LCD) and commercially available meal-replacement products would be useful for the management of obesity. The present study was designed to evaluate the efficacy and safety of this combination for weight loss and weight-loss maintenance as well as its effect on cardiovascular risk factors.

Eight US centers recruited 148 obese patients for a 3-month comprehensive weight-loss therapy (phase I) comprising daily sibutramine 10 mg + LCD (two Slim-Fast meal-replacement shakes, one low-calorie meal; total kcal/d = 1200 to 1500). Patients (N = 113) who lost >5% of initial body weight during phase I were randomized for a 9-month period (phase II) to daily sibutramine 15 mg + LCD (one meal-replacement shake; two low-calorie meals: total kcal/d approximately 1200 to 1500) or daily placebo + three low-calorie meals (total kcal/d = approximately 1200 to 1500). Both phases included behavior modification. Efficacy was assessed by body weight change during each phase and by the number of patients at endpoint maintaining >80% of the weight they had lost by the end of phase I. Other outcomes included changes in cardiovascular and metabolic risk factors, adverse events, and vital signs.

Mean body weight change during phase I was -8.3 kg. Patients randomized to sibutramine in phase II had an additional -2.5 kg mean weight loss versus a 2.8-kg increase in the placebo group. More sibutramine patients maintained >80% of their phase I weight loss at the end of phase II (85.5% versus placebo 36.7%). Most adverse events were mild or moderate in severity, and all serious adverse events were unrelated to sibutramine.

This study demonstrated that a combination therapy of sibutramine with LCD incorporating Slim-Fast meal replacements plus behavioral modification led to substantial weight loss over 3 months, and facilitated maintenance of weight loss over an additional 9-month period when compared with treatment with placebo plus LCD plus behavioral modification. Those patients randomized to the sibutramine-based combination therapy achieved additional weight loss in phase II, while patients in the placebo-based combination therapy showed a mean weight gain. The magnitude of weight loss observed in this study compares well to previous results from larger studies of sibutramine-assisted weight loss conducted at specialist hospital clinics and using complex lifestyle intervention.

In the present study, with only a 3-month weight-loss phase, over 85% of patients were able to lose at least 5% of their initial body weight with sibutramine-based combination therapy. Among those who were randomized to continue receiving sibutramine and completed the weight-maintenance phase, 83% maintained 80% or more of their original weight loss to 12 months. These data compare favorably with the results from the longer Sibutramine Trial of Obesity Reduction and Maintenance (STORM) trial, where 77% of patients were able to lose at least 5% of their initial body weight with sibutramine and dietary intervention in the 6-month open-label phase. Of those who completed the 18-month weight-maintenance phase of the STORM trial, 43% maintained 80% or more of their original weight loss.

Previous studies conducted with sibutramine have reported marked improvements in HDL-cholesterol levels, particularly during weight maintenance once the mobilization of lipids from fat stores into the circulation during the period of acute weight loss has passed. Thus, in this study, the beneficial effects of the substantial phase I weight loss on HDL levels observed in both treatment groups by 12 months, but not by 3 months, were expected. In both phases, changes in triglycerides mirrored weight changes. There was no difference between treatment groups in the prospective analysis of mean changes in HDL-cholesterol and triglyceride levels in phase II. A post hoc analysis of changes in these two lipid variables in patients receiving sibutramine and meal replacement throughout the study showed clinically meaningful and statistically significant beneficial changes in mean HDL cholesterol and triglycerides.

Sibutramine given with a diet that includes meal replacement helped 85% of obese patients lose 5% or more of their body weight and helped them to maintain that weight loss over 12 months. This amount of weight loss has the potential in these patients to reduce the chance of developing other obesity-related diseases. Waist circumference, a surrogate marker for abdominal fat and a major component of the metabolic syndrome, was also reduced.

There is a growing evidence base to support the use of meal-replacement products for use either alone or in combination in weight management strategies. More scientifically robust data are likely to be produced by the US National Institutes of Health (NIH)-funded Look AHEAD study, which is using meal replacements as part of an intensive weight-loss program delivered over 4 years to achieve weight loss among 5000 overweight and obese patients with type 2 diabetes. However, with an 11-year follow-up period, this study is not expected to report for some years.

In summary, there is a clear need for a variety of strategies to help overweight and obese people lose weight and maintain weight loss. The results of the present study suggest that the combination therapy of sibutramine plus an LCD incorporating Slim-Fast meal-replacement products supported by brief behavior modification sessions is a safe and effective strategy for achieving sustained weight loss in overweight and obese patients. This strategy of using sibutramine and meal replacement with a behavior program is an easy paradigm to incorporate into a family medicine practice environment.

J. Early, C. Apovian, L. Aronne, et al. Sibutramine Plus Meal Replacement Therapy for Body Weight Loss and Maintenance in Obese Patients. Obes Res; 15:1464-1472 (June 2007). [Correspondence: James Early, Department of Preventive Medicine and Public Health, University of Kansas School of Medicine, 1010 N. Kansas Rd., Wichita, KS 67214-3199. E-mail: jearly@kumc.edu.]


A GREEN TEA EXTRACT HIGH IN CATECHINS REDUCES BODY FAT AND CARDIOVASCULAR RISKS IN HUMANS

Tea is traditionally used as a medication based on experience, and the physiological activities of components of tea have been extensively described in Asian countries, mainly in Japan and China. Green tea contains catechins, a class of low molecular weight polyphenols that consist mainly of flavan-3-ol monomers; catechins are present mainly as catechin, catechin gallate, gallocatechin, gallocatechin gallate, epicatechin, epicatechin gallate, epigallocatechin, and epigallocatechin gallate (EGCG). Green tea leaves normally contain 10% to 20% catechins, mainly EGCG. Numerous studies of catechins’ antioxidant and anticancer action and their preventive effects on ischemic heart disease have attracted a great deal of attention.

The effects of catechins on energy and fat metabolism have recently been examined in humans. The studies conducted to date were conducted either on a small-scale (n < 100), or under a hypocaloric diet, or were gender-biased. Therefore, the present trial was conducted to clarify the body fat reducing effect of the continuous ingestion of a green tea extract (GTE) high in catechins in more than 200 Japanese women and men who were maintaining their usual lifestyles. They also examined the effects of a GTE high in catechins on risk factors of cardiovascular disease (CVD).

Japanese women and men with visceral fat-type obesity were recruited for the trial. After a 2-week diet run-in period, a 12-week double-blind parallel multicenter trial was performed, in which the subjects ingested green tea containing 583 mg of catechins (catechin group) or 96 mg of catechins (control group) per day. Randomization was stratified by gender and BMI at each medical institution. The subjects were instructed to maintain their usual dietary intake and normal physical activity.

Data were analyzed using per-protocol samples of 240 subjects (catechin group; n = 123, control group; n = 117). Decreases in body weight, BMI, body fat ratio, body fat mass, waist circumference, hip circumference, visceral fat area (VFA), and subcutaneous fat area (SFA) were found to be greater in the catechin group than in the control group. A greater decrease in systolic blood pressure (SBP) was found in the catechin group compared with the control group for subjects whose initial SBP was 130 mm Hg or higher. Low-density lipoprotein (LDL) cholesterol was also decreased to a greater extent in the catechin group. No adverse effect was found.

The effects of a GTE high in catechins on body fat and cardiovascular risk factors were investigated in an intervention trial without changing the usual lifestyle of the subjects. The dietary fat intake and fat energy ratio decreased from the initial level in both groups. These decreases might be caused by the seasonal change of the meal (spring to summer), but the usual dietary energy intake and exercise habits were maintained throughout the trial. During the treatment period, the intake of catechins and caffeine, including those in the test beverage, compared with the average for typical Japanese were 1.0 and 1.8 times in the control group, and 4.1 and 1.7 times in the catechin group, respectively. Under the above conditions, the ingestion of a beverage of GTE high in catechins for 12 weeks led to significant decreases in body weight, BMI, body fat ratio, body fat mass, waist circumference, hip circumference, TFA, VFA, and SFA. The results of the present trial further confirmed the results of previous studies on body fat in humans by expanding the population of subjects in number and gender. Decrease of LDL-cholesterol was also observed in the present trial, and this result further confirmed the results of the previous study. These findings suggest that the consumption of a GTE high in catechins may reduce the risk of the metabolic syndrome. It is possible that the mechanism by which catechins reduce body fat may be related to the increase of energy expenditure. In summary, this trial clarified that the continuous ingestion of catechins, especially in high amounts, reduces body fat, cholesterol levels, and blood pressure in women and men without the need for any lifestyle changes. The ingestion of a GTE high in catechins might prevent obesity and decrease the risk of CVD.

T. Nagao, T. Hase, I. Tokimitsu. A Green Tea Extract High in Catechins Reduces Body Fat and Cardiovascular Risks in Humans. Obes Res; 15:1473-1483 (June 2007). [Correspondence: Tomonori Nagao, Health Care Food Research Laboratories, Kao Corporation, 2-1-3, Bunka, Sumida-ku, Tokyo, 131-8501, Japan. E-mail: nagao.tomonori@kao.co.jp.]


INTERVENTIONS TO PREVENT OR TREAT OBESITY IN PRESCHOOL CHILDREN: A REVIEW OF EVALUATED PROGRAMS

The primary focus of public health initiatives is to help people become and remain healthy. Toward this end, there have been significant efforts to reduce the prevalence of obesity, which has increased substantially over the past 3 decades with a negative impact on health. National data indicate that overweight (BMI for sex and age >95th percentile) among preschool-age children in the United States has increased from 7.2% to 10.3% between the periods 1976 to 1980 and 1999 to 2002. Among preschool-age children from low-income families in 30 states, overweight (BMI >95th percentile) increased from 10.8% in 1989 to 13.7% in 2000, suggesting that it may be a slightly greater problem among children from low-income families. Moreover, studies have found strong links between BMI values in childhood and those in adulthood. Also, major causes of adult mortality, such as coronary heart disease and atherosclerosis, are associated with overweight during childhood. Other health conditions associated with overweight in childhood are higher blood pressure and serum insulin levels, adverse lipid levels, and orthopedic and psychosocial disorders.

Many approaches are being used to prevent and treat overweight among preschool-age children; however, the effectiveness of many intervention programs has not been evaluated. To increase the efficiency of fund use and the effectiveness of prevention efforts, it is imperative to identify and use successful programs. Although systematic reviews of interventions to prevent or treat overweight among children exist, there is no systematic review of interventions specific to preschool-age children.

The goal of the present study was to identify and summarize effective evaluated interventions to prevent or treat obesity among preschool children. The researchers searched six databases to identify evaluated intervention programs assessing changes in weight status or body fat and systematically summarized study attributes and outcomes.

Four of the seven studies (two intervention, two prevention) documented significant reductions in weight status or body fat. Among these, three sustained reductions at 1 or 2 years after program initiation, three incorporated a framework/theory, two actively and one passively involved parents, three included multicomponent strategies, and all four monitored behavioral changes. Of the three (prevention) studies that did not show reduction in weight or fat status, all performed assessments between 4 months and 9 months after program initiation, and one used a multicomponent strategy. Other significant changes reported were reductions in television viewing, cholesterol, and parental restriction of child feeding.

The initial search yielded only seven interventions to prevent or treat overweight or to enhance the nutritional status of 9- to 70-month-old children that measured weight status to evaluate impact. Of these seven studies, two of the five prevention studies and both treatment studies reported a statistically significant reduction in weight status or body fat, and one other prevention study reported a reduction that approached significance.

The interventions reviewed used a variety of frameworks/theories and strategies to prevent or treat overweight. The only theory used by more than one study was the Social Learning Theory. Interestingly, in this review, four of the seven studies based their intervention on a framework or theory, and only two of these four studies documented reductions in weight status. The other two studies based on theories found either a close-to-significant reduction in weight status or reduced cholesterol levels. Of the studies that did not base their interventions on a framework or theory, two may have achieved weight loss because they either used a classroom program of physical activity with good compliance, or the treatment program had individual child/parent counseling sessions that monitored behavioral changes in diet and exercise. The other study focused on reducing TV viewing at home through daycare-based programs that included developing alternative activities to TV viewing at home; however, the use of these specific alternatives was not reported, so it is not known whether they would have the potential to reduce weight status.

Of the seven interventions reviewed, five used both nutritional/diet- and physical activity-focused strategies. Among the four studies that achieved significant weight loss among the participants, three used some form of nutrition education or diet component (one treatment, two prevention), all four (two prevention, two treatment) included either guidance for or a directed physical activity program, and one (prevention) gave remuneration. Moreover, the three prevention interventions that did not report significant reductions in weight status used similar approaches; all had a diet, but only one included directed physical activity, and one provided remuneration.

Behavioral outcomes of these interventions were based primarily on parental reports; four studies used objective measures, but three studies either did not monitor behavior changes or used techniques that were more subjective, which could have biased parental reporting.

Researchers used either the child exclusively or a family or parent focus as the entrée to implement the different strategies. Among the four interventions that reported a reduction in weight or body fat status, the two treatment studies actively involved the parents in education and activities, which included goal setting and follow-up; for the two prevention studies, one passively involved parents by sending materials home weekly, and the other involved only the children. As for the three prevention studies that did not demonstrate a weight change, one used parents as the agents of change, two sent home to parents educational materials that included parent activities, and one included educational group meetings for parents three or four times during the school year.

The finding that two of the four programs that successfully reduced weight or fat status actively included the parents and another sent materials home to parents on a weekly basis suggests that more work is needed to examine how active parental involvement needs to be in intervention programs for young children.

The review demonstrated success in a variety of locations. In-home, day care, Head Start, preschool, and clinic settings all were shown to be options for implementing effective interventions. However, because each intervention was implemented in one type of setting and may have included only one racial or ethnic group, future studies need to examine the effectiveness of these programs implemented in different intervention settings for different income and racial/ethnic groups. Income data were not available in some of the studies reviewed, so this issue was not examined.

All of the studies reviewed were actively trying to reduce BMI, weight-for-height, or body fat through behavior change. Among the studies here, the variables exhibiting significant change were weight status, energy intake or percentage of calories from saturated fat, TV viewing time, maternal restriction of child feeding, and serum cholesterol. These studies provide a strong base to further develop effective interventions. Clearly, more interventions need to be implemented and evaluated. A first step would be to evaluate the effectiveness of the preceding interventions among other racial/ethnic groups and in other settings.

The finding that five of the seven interventions reviewed used multicomponent strategies, and the interventions used a variety of settings and frequently included parents as agents of change, could be considered a model coincident with the Institute of Medicine’s recommendation that because obesity has a variety of causes, a multicomponent intervention program, focusing on more than one strategy, using a variety of settings, and involving parents and other adults such as teachers, is likely to be more effective in preventing overweight. In conclusion, there are great opportunities for further work in developing and evaluating intervention programs to prevent or treat overweight among preschool children.

D. Bluford, B. Sherry, K. Scanlon. Interventions to Prevent or Treat Obesity in Preschool Children: A Review of Evaluated Programs. Obes Res; 15:1356-1372 (June 2007). [Correspondence: Bettylou Sherry, Maternal and Child Nutrition Branch, Mail Stop K-25, Division of Nutrition and Physical Activity, National Center for Chronic Disease Prevention and Health Promotion, Centers for Disease Control and Prevention, 4770 Buford Highway NE, Atlanta, GA 30341-3717. E-mail: bsherry@cdc.gov.]


DOES A HIGH-PROTEIN DIET IMPROVE WEIGHT LOSS IN OVERWEIGHT AND OBESE CHILDREN?

Like adult obesity, childhood obesity prevalence is rising, making it imperative that treatment programs are developed and supported. As these children move into adulthood, they will be at risk for an associated increase in physical and psychological morbidity. It is vital to treat obesity in childhood because lifestyle behaviors that contribute to and sustain obesity in adults are less well established in children and may be more amenable to change. Short-term weight loss in pediatric patients has previously been achieved in trials involving various methods for the control of both diet and activity level. These include energy and fat reduction, adherence to a low-carbohydrate diet, participation in structured, vigorous physical activity, and a reduction in sedentary behavior. However, one of the consequences of achieving a dietary-induced negative energy balance is an increase in hunger, at least in adults.

One approach might be to increase the proportion of dietary protein consumed. Weigle et al., suggest that there are two mechanisms by which increased dietary protein impedes an increase in the drive to eat--usually experienced during negative energy balance. The first is the capacity of dietary protein to increase energy expenditure, due partly to greater diet-induced thermogenesis after protein consumption than after consumption of equally calorific loads of carbohydrate or fat. The second is the greater satiating power of protein compared with the other macronutrients. Weigle et al., demonstrated that an increase in protein intake from 15% to 30% of energy, at a constant carbohydrate intake of 50% of energy, resulted in subjects reporting a clear decrease in hunger and increase in fullness. This effect has been demonstrated in short-term feeding studies, in long-term studies with imposed caloric restrictions, and in spontaneous energy intake where participants consuming more dietary protein consumed less energy in subsequent meals.

Very little is known about how obese children respond to a high-protein, energy-controlled diet and whether it is associated with similar weight loss and satiety-enhancing properties. The researchers of this study have recently reported the short-term benefits to overweight and obese children attending a residential weight-loss camp. Over a period of 4 weeks, these children lost an average of 6.0 kg and reduced their BMI by 2.4 kg/m2 and BMI standard deviation scores (SDSs) by 0.28. However, they also observed a significant increase in hunger and a decrease in fullness over the course of the camp program.

The residential weight-loss camp provides an opportunity to achieve good control over variables that affect energy balance over a medium-term period, while maintaining free living conditions. Although the camp focus is on participation in a variety of physical activities, children’s food intake is carefully controlled. As such, it is possible to alter the nutrient profile of the food offered and increase the protein content of the diet. The aim of the present study, therefore, was to compare the effect of a higher protein diet (22.5% of total energy intake) with a standard protein diet (15% protein) on weight loss, hunger and satiety in a controlled environment. It was hypothesized that children consuming the higher protein diet would experience greater weight loss and improved satiety compared with children consuming the standard diet.

Children (120; BMI, 33.1 kg/m2 ± 5.5 kg/m2; age, 14.2 years ± 1.9 years) were randomly assigned to either a standard or high-protein diet group (15% versus 22.5% protein, respectively). All children were assessed at baseline and at the end of the camp for anthropometry, body composition, blood pressure, biochemical variables (n = 27), and subjective appetite and mood sensations (n = 50).

Attendance at the weight-loss camp resulted in significant improvements in most measures. Campers lost 5.5 kg ± 2.9 kg in body weight and 3.8 kg ± 5.4 kg in fat mass and reduced their BMI standard deviation score by 0.27 ± 0.1 and their waist circumference by 6.6 cm ± 2.8 cm. Subjective sensations of hunger increased significantly over the camp duration, but no other changes in appetite or mood were observed. There were no significant differences between the two diets on any physical or subjective measures.

This study demonstrated that a 50% increase in daily energy intake provided by protein had no significant impact on changes in body weight, body composition, appetite, mood, or perceived palatability. Regardless of the protein composition of their diet, these children lost similar amounts of weight, derived similar physiological benefit, and experienced similar changes in motivation to eat.

In conclusion, this study has confirmed the capacity for a summer residential activity-based camp to help overweight and obese children to lose weight. It also supports the observation that prolonged negative energy balance is associated with an increase in hunger motivation. However, randomizing children to a high-protein diet failed either to facilitate weight loss or to suppress hunger. Further work is warranted to investigate whether higher levels of dietary protein are feasible or effective in longer term weight loss interventions of this type.

P. Gately, N. King, H. Greatwood, et al. Does a High-protein Diet Improve Weight Loss in Overweight and Obese Children? Obes Res; 15:1527-1534 (June 2007). [Correspondence: Paul J. Gately, School of Sport, Exercise, and Physical Education, Leeds Metropolitan University, Fairfax Hall, Headingley Campus, Leeds LS6 3QS, UK. E-mail: p.gately@leedsmet.ac.uk.]


PHYSICAL ACTIVITY LEVELS OF NORMAL-WEIGHT AND OVERWEIGHT GIRLS AND BOYS DURING PRIMARY SCHOOL RECESS

The physical activity and adiposity of children is currently a major public health concern primarily because of the consistent upward trend in overweight in youngsters. Obese children have an increased acute risk of insulin resistance, type 2 diabetes, and dyslipidemia. Overweight youngsters are also more likely to experience clustered risk--and have lower levels of physical activity--and to suffer poorer psychological health than their normal-weight peers. Furthermore, overweight youngsters are at increased risk for adult overweight and obesity. Being overweight has long-term consequences on all-cause mortality and CVD, which suggests that the prevention and treatment of overweight at an early age could reduce the impact of future adult disease and promote health and well being. Physical activity and diet are the obvious bedrocks of combating overweight. Young children best accumulate physical activity in play environments. One context where physical activity is permissible on a daily basis is the primary school playground. The majority of primary school children have 15 recess periods per week. The duration of recess varies, with each day being made up of a 15-minute midmorning play, 1 hour for lunch (of which over 30 minutes represents recess), and a 15-minute midafternoon break. Other than extracurricular sports and curriculum physical education, primary school recess time represents the largest block of school time for children to engage in physical activity. Primary school children spend about a fifth of their school life on the playground, equating to 600 recess periods per year [3 per day, 5 days per week, 39 weeks per year].

Data on physical activity levels during recess are emerging with physical activity targets proposed for "health promoting playgrounds" of 50% and 40% of recess time. Ridgers et al, reported that children engaged in 34 minutes of moderate-to-vigorous physical activity (MVPA), if they were active for 40% of recess time. Thirty-four minutes of physical activity exceeds the 30-minute minimum MVPA recommendation for children.

The fact that most children are exposed to school recess, which is largely peer controlled with no computer games, televisions, or mobile telephones to suppress physical activity, helps pose a relevant question: first, do boys and girls in normal-weight (<85th percentile for BMI) and overweight (>85th percentile BMI) categories differ in the amount of time they spend in physical activity during recess? Second, how many children in each weight category achieve the target of 40% or 50% of MVPA during school recess?

Therefore, the aims of this investigation were twofold. The first aim was to investigate whether normal-weight children were more active than their overweight peers and to investigate whether boys were more active than girls. The second aim was to compare the proportion of normal-weight and overweight children that would meet the 40% and 50% activity thresholds for recess activity.

Four hundred and twenty children, age 6 to 10 years, were randomly selected from 25 schools in England. Three hundred and seventy-seven children completed the study. BMI was calculated from height and weight measurements, and heart rate reserve thresholds of 50% and 75% reflected children’s engagement in MVPA and VPA, respectively.

There was a significant main effect for sex and a significant interaction between BMI category and sex for the percent of recess time spent in MVPA and VPA. Normal-weight girls were the least active group, compared with overweight boys and girls who were equally active. Fifty-one boys and 24 girls of normal weight achieved the 40% threshold; of these, 30 boys and 10 girls exceeded 50% of recess time in MVPA. Eighteen overweight boys and 22 overweight girls exceeded the 40% threshold, whereas 8 boys and 8 girls exceeded the 50% threshold.

Results revealed that normal-weight boys and girls spent over a third and a fourth of recess time in MVPA, respectively. Both boys and girls who were overweight spent approximately 30% of recess in MVPA. The significant main effect for sex demonstrated that boys were more active than girls during recess. These data agree with other research on physical activity during recess in primary-aged children. Furthermore, the results from this study support the extant literature in that normal-weight boys were more active than their overweight counterparts. However, the same did not hold true for overweight girls, who were more moderately and vigorously active than girls of normal weight. The phenomenon of similar levels of physical activity in normal-weight and overweight girls is difficult to explain. It could be attributed to the structure and organization of playgrounds, where girls and nonathletic boys are marginalized and, thus, less active.

As a consequence, girls and overweight boys take part in less active games, use smaller amounts of playground space, and engage in less vigorous and competitive activity. Girls also seem to prefer "walking and talking," as well as dance and game activities that involve the upper body more than the lower body. Boys, on the other hand, engage in more physical activity regardless of the structure of the playground, as their games are generally vigorous and involve more high-intensity running-type activities than girls’ games. However, in this study, overweight boys were less active than those of normal weight. Therefore, other factors, such as motor skill, may be related to participation in male dominated playground games in overweight boys. No literature is available on this issue in the context of school recess. It is possible that overweight boys had poorer motor skills compared with their normal-weight peer group and, consequently, were excluded from vigorously active games (such as soccer) that are popular for boys during school recess.

What is apparent from this study is that traditional playgrounds do not promote equal amounts of physical activity for overweight girls and boys. Thus, on average, playgrounds only succeed in promoting appropriate amounts of physical activity in normal-weight boys. These reports go some way to explaining why sex differences in physical activity exist during recess. While the differences between girls and boys activity has been reported elsewhere in the literature, few data exist on gender and weight differences in physical activity during recess.

The second aim of this investigation was to quantify the frequency of normal-weight and overweight boys and girls who exceeded the 40% and 50% thresholds of MVPA during recess. In this study, 40% of recess equated to 34.5 minutes, indicating that these children achieved the minimum physical activity target of 30 minutes through recess alone. It seems that the 40% of MVPA during recess is a more realistic and achievable activity target, particularly for children who are overweight, compared to the 50% goal. These data somewhat muddy the picture regarding physical activity intervention since a significant number of overweight children met the 40% target for MVPA during recess, suggesting that factors other than BMI also have an impact on children’s activity levels in this context.

In summary, this study aimed to assess differences in physical activity levels between overweight girls and boys during school recess. It also set out to calculate the number of children in each group who met the recently proposed physical activity targets of 40% and 50% of recess time in MVPA. Normal-weight boys were significantly more active than the overweight boys and girls and normal-weight girls for both MVPA and VPA. Even though twice as many normal-weight boys were active for 40% of recess, compared with normal-weight and overweight girls and overweight boys, over 20% of children in the normal-weight and overweight girls and overweight boys groups also attained this threshold. Finally, normal-weight boys use recess time as an opportunity to be significantly more active than normal-weight and overweight girls and overweight boys. Future studies that aim to increase physical activity in obese and overweight children should be cognizant of these findings when planning physical activity interventions.

G. Stratton, N. Ridgers, S. Fairclough, et al. Physical Activity Levels of Normal-Weight and Overweight Girls and Boys during Primary School Recess. Obes Res; 15:1513-1519 (June 2007). [Correspondence: Gareth Stratton, Research Institute for Sports and Exercise Sciences, 15-21 Webster Street, Liverpool John Moores University, Liverpool, UK. E-mail: G.Stratton@ljmu.ac.uk.]


HERITABILITY OF HYPERPHAGIC EATING BEHAVIOR AND APPETITE-RELATED HORMONES AMONG HISPANIC CHILDREN

Obesity among children fundamentally arises from a dysregulation of energy intake and expenditure. The central nervous system (CNS) regulates food intake by responding to afferent hormonal signals, such as insulin, leptin, and adrenal steroids, generated in proportion to adipose tissue mass. Superimposed on this negative feedback system are short-term signals to the CNS, such as cholecystokinin, glucagon-like peptide 1, amylin, and ghrelin, that modulate meal size and duration. Food intake is also influenced by the environment in which eating occurs and the effects of those conditions on learned behavior. Obesigenic dietary environments are thought to encourage eating behaviors that favor positive energy balance by exposing children to large portion sizes of palatable, energy-dense foods. Relevant eating phenotypes and their correspondence to primary hormonal regulators of food intake, however, are poorly described in children.

Among adults, BMI and weight gain are positively associated with disinhibited eating, which reflects a loss of control over eating or overeating in response to emotional or environmental stimuli. By preschool, some children exhibit behavior in the laboratory that is analogous to adult disinhibition by eating relatively large amounts of energy when given access to generous portions of palatable foods in the absence of hunger. Eating in the absence of hunger (EAH) appears to be a stable characteristic of eating in young girls and is positively associated with weight status during middle childhood. Studies of EAH have been largely limited to well-educated non-Hispanic white families. Whether EAH represents a behavioral phenotype of overweight children and adolescents in ethnic populations disproportionately affected by obesity has not been established.

To date, restrictions placed on children’s eating habits seem to be the primary environmental correlate of EAH in young girls. A recent study of 53 5-year-old children, however, provides evidence that EAH is also, in part, unlearned. Boys, but not girls, who were at high risk for obesity based on maternal prepregnancy weight showed higher levels of EAH than those children at low risk. Higher levels of maternal disinhibition have also been associated with greater EAH among children, also suggestive of genetic and/or familial modeling influences. That heredity would influence children’s susceptibility to eat in the absence of hunger is probable given growing appreciation of genetic influences on many aspects of appetitive behavior, including taste sensitivity, food preference, intake of specific foods, meal patterns, energy density and macronutrient intake, and meal and daily energy intake. Few genetic studies of eating behavior, however, have focused specifically on behavioral aspects of the imbalance between energy intake and needs, specifically hyperphagic eating behavior.

This research used a family design to measure EAH after a standard ad libitum meal providing 50% of estimated daily energy needs in a large sample of male and female Hispanic children ranging from 5 years to 18 years. The primary objective was to evaluate EAH as a behavioral phenotype of overweight Hispanic children. That is, whether overweight children show greater levels of EAH than nonoverweight children was determined. A secondary objective was to estimate the heritability (h2) of EAH and evaluate genetic associations with long-term (insulin and leptin) and short-term (amylin and ghrelin) hormonal signals implicated in the regulation of food intake and obesity.

A family design was used to study 801 children from 300 Hispanic families. Weighed food intakes were used to measure EAH after an ad libitum dinner providing 50% of estimated energy needs. Fasting ghrelin, amylin, insulin, and leptin were measured by immunoassays. Measured heights, weights, and fat mass [using dual energy X-ray absorptiometry (DXA)] were obtained. Total energy expenditure (TEE) was measured by room respiration calorimetry.

On average, children consumed 41% of TEE at the dinner meal, followed by an additional 19% of TEE in the absence of hunger. Overweight children consumed 6.5% more energy at dinner and 14% more energy in the absence of hunger than nonoverweight children. Significant heritabilities were seen for EAH and dinner intake and for fasting levels of ghrelin, amylin, insulin, and leptin. Genetic correlations were seen between eating behavior and fasting hormones, suggesting common underlying genes affecting their expression.

Rapid increases in the prevalence of pediatric obesity in recent decades suggest that mechanisms for the self-regulation of energy intake can be readily overridden when children eat in abundant dietary environments. These results provide new evidence that excessive energy intake at meals and in the absence of hunger are strongly heritable behavioral phenotypes of Hispanic children. In this study, some subjects consumed up to 3160 kcal within the 1-hour timeframe of the experiment. The relatively large amount of energy consumed in a short period suggests that the predisposition for these hyperphagic eating behaviors could potentially widen the energy gap among overweight Hispanic children.

Energy consumed in the absence of hunger was 17% greater among boys than among girls in absolute terms; however, this difference was not apparent when EAH was expressed as a percentage of TEE. EAH increased with age (44 kcal/yr), leveling off and declining slightly during adolescence. That EAH did not vary with age when expressed as a percentage of TEE indicates that the age-related increases in energy intake were proportional to the children’s capacity. Developmental changes in the behavioral controls of eating could reflect cumulative exposure to experiences that de-emphasize children’s attention to internal cues of hunger and satiety, such as highly controlling feeding practices, peer or adult models of excessive intake, and social norms that encourage frequent eating, large portion sizes, and so on.

In conclusion, the results of this investigation provide evidence that EAH is pronounced among overweight Hispanic children and is under significant genetic control. These findings suggest that Hispanic children who are predisposed to high ad libitum energy intake at meals and in the absence of hunger are likely to be adversely affected by abundant dietary environments. Furthermore, these findings provide new evidence of common genetic pathways underlying these hyperphagic behaviors, regulatory hormones (insulin, leptin, amylin, and ghrelin), and body habitus. A prevailing view of the etiology of obesity is that environmental factors promote behaviors that favor obesity among genetically susceptible individuals. The findings of this research underscore the role of genetic susceptibility in childhood obesity as one that extends beyond body weight and adiposity to the behavioral controls of eating.

J. Fisher, G. Cai, S. Jaramillo, et al. Heritability of Hyperphagic Eating Behavior and Appetite-Related Hormones among Hispanic Children. Obes Res; 15: 1484-1495 (June 2007). [Correspondence: J. O. Fisher, US Department of Agriculture/Agricultural Research Service Children’s Nutrition Research Center, 1100 Bates Street, Suite 4004, Houston, TX 77030. E-mail: jfisher@bcm.tmc.edu.]


BMI; OBESITY; AND SICKNESS ABSENCE IN THE WHITEHALL II STUDY

Population-wide increases in obesity and overweight in postindustrial countries have occurred rapidly over the last 20 years, and obesity is now more prevalent than undernutrition in some less developed countries. Obesity and overweight increase mortality and have been associated with a range of chronic diseases. Because the association between BMI and mortality risk is U-shaped, underweight and weight change are also predictive of premature mortality and disease. In addition to effects on physical health, weight and weight change are known determinants of mental health and well-being. Another issue that has attracted attention over the last 20 years is the cost of absence from work because of sickness, with concern expressed about the level of absence in a number of European and Scandinavian countries. Even in the UK, where absence rates are relatively low, there is concern about long-term sickness absence and high levels of absence in the public sector.

Existing studies of obesity, overweight, and sickness absence are relatively few and have produced conflicting results. Some studies report a considerable excess risk of sickness absence for obese and overweight employees, whereas others report no excess risk. However, apart from work site intervention studies that were unable to detect associations at the individual level, no studies seem to have investigated associations between BMI measured on more than one occasion and sickness absence. The purpose of this study is to examine BMI and change in BMI from age 25 as predictors of sickness absence. Data are from the Whitehall II study, a prospective cohort of white collar women and men employed in the British Civil Service.

Data were collected from 2564 women and 5853 men, who were British civil servants (35 years to 55 years) on entry to the Whitehall II study (phase 1, 1985 to 1988). Employer’s records provided annual medically certified (long, >7 days) and self-certified (short, 1 day to 7 days) spells of sickness absence. BMI at age 25 and phase 1 were examined in relation to absences from phase 1 to the end of 1998 (mean follow-up, 7.0 years).

After adjustment for employment grade, health-related behaviors, and health status, overweight (BMI = 25.0 kg/m2 to 29.9 kg/m2) and obesity (BMI > 30.0 kg/m2) at phase 1 were significant predictors of short and long absences in both sexes; rate ratios (95% confidence intervals) ranged from 1.13 (1.05 to 1.21) to 1.51 (1.30 to 1.76) compared with a BMI of 21.0 kg/m2 to 22.9 kg/m2. Additionally, a BMI of 23.0 kg/m2 to 24.9 kg/m2 at phase 1 predicted long absences in women, and underweight (BMI < 21.0 kg/m2) predicted short absences in men. Obesity at age 25 predicted long absences, and obesity at phase 1 predicted short and long absences in both sexes. Chronic obesity was a particularly strong predictor of long absences in men, with a rate ratio of 2.61 (1.88 to 3.63).

This seems to be the first large-scale observational study to examine associations between BMI measured on more than one occasion and sickness absence. It shows that obesity (BMI >30 kg/m2) either at age 25 or phase 1 (age 35 to 55) increases long spells of sickness absence by approximately 60% in both sexes and increases short spells of absence in men by 25%. The effects of obesity at both age 25 and phase 1 had a multiplicative effect on the risk of long spells of sickness in men, but not in women. However, being overweight (BMI = 25 kg/m2 to 29.9 kg/m2) at age 25 added nothing to the prediction of sickness absence beyond the contribution of being overweight or obese at phase 1. These findings confirm those of previous studies that have shown independent associations of overweight and obesity with higher rates of short and long spells of absence in both sexes. In addition, this study showed that a BMI of 23.0 kg/m2 to 24.9 kg/m2 at phase 1 was a significant predictor of long absences in women and underweight was a significant predictor of short absences in men.

In addition to adverse effects on individual health and pressure on services, these findings indicate that the current obesity epidemic is also likely to result in significant increases in sickness absence, particularly longer-term sickness absence. Although further research is needed to understand all of the mechanisms underlying this association, given that the current epidemic seems set to continue, it would be unethical to delay the implementation of weight reduction interventions. Existing work site interventions aimed at health promotion in general or weight reduction in particular have had limited success in achieving and maintaining weight losses. A comprehensive population approach to weight control and weight reduction is the strategy most likely to be successful both for the reduction of weight and the concomitant effects on health and sickness absence. Such a strategy would include input at the level of the workplace to tackle the contribution of unhealthy diets, sedentary work, and weight-sustaining work environments.

J. Ferrie, J. Head, M. Shipley, et al. BMI, Obesity, and Sickness Absence in the Whitehall II Study. Obes Res; 15:1554-1564 (June 2007). [Correspondence: Jane Ferrie, Department of Epidemiology and Public Health, University College London Medical School, 1-19 Torrington Place, London WC1E 6BT, UK. E-mail: j.ferrie@public-health.ucl.ac.uk.]


EXERCISE EFFECT ON WEIGHT AND BODY FAT IN MEN AND WOMEN

The worldwide epidemic of overweight and obesity has resulted in calls for prevention and treatment strategies. Scientific tests of weight reduction diets have shown modest long-term efficacy. The US Department of Agriculture now recommends that to help manage body weight and prevent gradual, unhealthy body weight gain in adulthood, individuals should engage in approximately 60 minutes of moderate-to-vigorous-intensity activity on most days of the week while not exceeding caloric intake requirements. The Institute of Medicine recommends that adults and children spend a total of at least 1 hour each day in moderately intense physical activity. However, the long-term efficacy of this level of daily physical activity on weight control in the absence of dietary change has not been established. In contrast, the US Center for Disease Control and American College of Sports Medicine recommend 30 min/d of at least moderate activity on most days of the week.

Increased intra-abdominal obesity is associated with insulin resistance, type 2 diabetes, hypertension, dyslipidemia, and CVD and could be important in promoting cancers of the colon, breast, and endometrium. In contrast, subcutaneous fat may be more important in excessive nongonadal production of sex hormones, which increase risk for breast and endometrial cancer. The purpose of this study was to assess, in a randomized, controlled clinical trial, the effect of a 12-month moderate-to-vigorous intensity exercise program (60 min/d, 6 d/wk) on weight, anthropometrics, and body composition (percentage body fat) and abdominal fat (total, intra-abdominal and subcutaneous) in women and men.

This was a 12-month randomized, controlled clinical trial testing exercise effect on weight and body composition in men (N = 102) and women (N = 100). Sedentary/unfit persons, 40 years to 75 years old, were recruited through physician practices and media. The intervention was facility- and home-based moderate-to-vigorous intensity aerobic activity, 60 min/d, 6 days/wk versus controls (no intervention).

Exercisers exercised a mean 370 min/wk (men) and 295 min/wk (women), and seven dropped the intervention. Exercisers lost weight (women, -1.4 kg versus +0.7 kg in controls; men, -1.8 kg versus -0.1 kg in controls), BMI (women, -0.6 kg/m2 versus +0.3 kg/m2 in controls; men, -0.5 kg/m2 versus no change in controls), waist circumference (women, -1.4 cm versus +2.2 cm in controls; men, -3.3 cm versus -0.4 cm in controls), and total fat mass (women, -1.9 kg versus +0.2 kg in controls; men, -3.0 kg versus +0.2 kg in controls). Exercisers with greater increases in pedometer-measured steps per day had greater decreases in weight, BMI, body fat, and intra-abdominal fat. Similar trends were observed for increased minutes per day of exercise and for increases in maximal oxygen consumption.

This randomized, controlled clinical trial showed that moderate-to-vigorous intensity exercise, such as that recommended by the US Department of Agriculture, results in significant weight and fat loss over 12 months in sedentary individuals. The mean weight loss (1.4-kg decrease in female exercisers versus 0.7-kg gain in female controls, 1.8-kg decrease in male exercisers versus 0.1-kg decrease in male controls) was modest, but is similar to that observed with some low-fat dietary interventions over a comparable timeframe. This is promising because some individuals may prefer to control weight through exercise rather than (or as well as) through restrictive diets.

Female exercisers who recorded mean pedometer step increases >3520 steps/d (comparable with increasing >2 miles/d in distance) lost 2.3 kg over the 12-month intervention. Male exercisers who reported this level of increased steps per day lost a mean 3.9 kg over 12 months. This weight loss in the high adherers (roughly one-third of the exercisers) represented a loss of 3% and 4% of baseline weight in women and men, respectively. Because weight loss through dietary means of as little as 5% can have beneficial clinical effects, it is likely that adoption of an exercise program such as this that includes a goal of 60 min/d of moderate or vigorous activity will be clinically relevant through its effect on body composition, in addition to beneficial effects of exercise independent of effects on adiposity. The lack of weight gain in most exercisers is also promising because weight gain over adult years significantly increases risk of several diseases.

In conclusion, this year-long, randomized, controlled trial testing a moderate-to-vigorous intensity exercise intervention produced statistically significant decreases in body weight, BMI, waist and hip circumferences, and total body fat and a suggestion of greater losses of intra-abdominal fat with higher duration of exercise or greater gains in fitness. These data support the US Department of Agriculture and Institute of Medicine guidelines of a goal of 60 min/d of moderate-to-vigorous physical activity.

A. McTiernan, B. Sorensen, M. Irwin, et al. Exercise Effect on Weight and Body Fat in Men and Women. Obes Res; 15:1496-1512 (June 2007). [Correspondence: Anne McTiernan, Fred Hutchinson Cancer Research Center, 1100 Fairview Avenue N, M4-B402, Seattle, WA 98109-1024. E-mail: amctiern@fhcrc.org.]


PEDOMETER USE INCREASES PHYSICAL ACTIVITY OF LOW-INCOME WOMEN

The prevalence of physical inactivity is escalating in the United States, especially among minority women. In 2001, the Behavioral Risk Factor Surveillance System revealed that 54.6% of US adults perform less than 30 minutes of moderate physical activity each day. Levels of physical activity vary by sex, age, ethnicity, and socioeconomic status. African Americans, older adults, and persons of lower socioeconomic status are population subgroups that are more likely to be inactive. Among women, those with young children are less likely to engage in regular physical activity than women without children.

A potentially effective strategy for promoting physical activity in interventions is the use of pedometers as a self-monitoring tool. The conceptual framework underlying this intervention is based on the self-efficacy theory. Bandura defined self-efficacy as the confidence that an individual has to perform a particular activity, such as exercise. Other studies show a link between levels of exercise self-efficacy and motivational readiness to change exercise behavior. Motivational readiness for exercise is a concept that relates behavior change to a process of movement through the stages of precontemplation, contemplation, preparation, action, and maintenance. Therefore, investigators hypothesize that mothers will increase their motivational readiness to exercise and exercise self-efficacy following an exercise and dietary intervention. In addition, this investigation aimed to examine the effectiveness of pedometers for increasing physical activity levels and reducing body weight among low-income mothers.

The program measured pre/postdifferences in an 8-week physical activity and dietary program. Overweight and obese mothers in the intervention group (n=124) completed demographic, motivational readiness for exercise, and exercise self-efficacy questionnaires and recorded pedometer steps for 3 days at weeks 0 and 8. Additionally, program evaluation forms were administered at week 8. Anthropometrics were measured at weeks 0, 8, and 24 for an assessment of weight maintenance. Also, demographics, motivational readiness for exercise, exercise self-efficacy, and anthropometrics were assessed at baseline only for healthful-weight mothers of similar socioeconomic status and ethnicity to provide comparison data (BMI <25, n = 38).

Mothers enhanced their motivational readiness to exercise, exercise self-efficacy, pedometer steps, and pedometer kilocalories. Reductions in body weight, percent body fat, and waist circumference also were observed. Significant correlations were found between exercise self-efficacy and exercise readiness (r = 0.28, P < 0.01), pedometer steps (r = 0.30, P < 0.01), and pedometer kilocalories (r = 0.28, P < 0.05).

This type of intervention appears to be able to successfully increase the physical activity levels of and promote weight loss in low-income mothers.

K. Clarke, J. Freeland-Graves, D. Klohe-Lehman, et al. Promotion of Physical Activity in Low-Income Mothers Using Pedometers. J. Am. Diet. Assoc.; 107:962-967 (June, 2007). [Correspondence: Jeanne Freeland-Graves, PhD, RD, The Bess Heflin Centennial Professor, Division of Nutritional Sciences, 1 University Station, A2700, The University of Texas at Austin, Austin, TX 78712. E-mail: jfg@mail.utexas.edu.]


THE EFFECT OF LARGE PORTION SIZES ON ENERGY INTAKE IS SUSTAINED FOR 11 DAYS

The recent surge in rates of overweight and obesity indicates that an increasing number of individuals are consuming more energy than they are expending. Understanding this dysregulation of energy balance is critical to the development of strategies to prevent obesity. A number of studies show that energy intake at meals can be affected by food characteristics, such as variety, energy density, and portion size, and that these effects are sustained over several days. A key question is whether such food-related influences on consumption can override physiological regulatory systems and continue to influence intake over longer periods. In this study, the researchers determine whether the effect of increased portion sizes on energy intake persists over 11 days.

Large portion sizes are often cited as an example of an environmental influence associated with increased energy intake. Increasing the portion size of a variety of types of foods in both controlled and naturalistic situations has been shown to have significant and robust effects on energy intake at a single meal or a snack. Furthermore, in a controlled study conducted over 2 days, increasing the portion sizes of all available foods by 50% resulted in a significant and sustained 16% increase in intake. In a similar study, a 33% increase in portion sizes led to an 11% increase in energy intake that was sustained over 2 days. These two studies showed no evidence that compensatory mechanisms led to an adjustment in energy intake over a 2-day period in response to increased consumption.

The stability of body weight in some individuals suggests that even if energy intake is not closely regulated over several days, modifications may be made in response to excess intake over longer periods. It is not clear how long it might take for such compensatory behavior to occur. The purpose of this study was to determine whether a 50% increase in the portion sizes of all foods and caloric beverages provided over 11 consecutive days would be associated with a sustained increase in energy intake, or whether regulatory mechanisms would lead to adjustments in food intake over time. It was also of interest to investigate whether the effect of portion size would be similar for different types of foods. This study will lead to a better understanding of how the food environment influences the regulation of energy intake.

Participants in the study were 23 normal-weight and overweight participants (10 women and 13 men). All of their foods and caloric beverages were provided during two different periods of 11 consecutive days, which were separated by a 2-week interval. During one period, standard portions of all items were served; during the other, all portion sizes were increased by 50%.

The 50% increase in portion sizes resulted in a mean increase in daily energy intake of 423 kcal ± 27 kcal, which did not differ significantly between women and men. This increase was sustained for 11 days and did not decline significantly over time, leading to a mean cumulative increase in intake of 4636 kcal ± 532 kcal. A significant effect of portion size on intake was seen at all meals and in all categories of foods except fruit (as a snack) and vegetables. The effect of portion size on intake was not influenced by the body weight status of participants.

The results of this study extend previous findings by showing that the effect of large portion sizes on energy intake is sustained not just for 2 days, but for as long as 11 days. The 50% increase in portion sizes resulted in a mean increase in intake of 423 kcal per day over the 11 days of the study, for an average cumulative increase of 4636 kcal. The magnitude of the effect of portion size on intake was similar to that of the previous 2-day studies. In the present study, a 50% increase in portion sizes over 11 days led to an increase in daily energy intake of 25% in women and 14% in men, resulting in intakes in excess of estimated energy requirements. These results strengthen the evidence suggesting that increased portions contribute to the over-consumption of energy and may lead to excess body weight.

This study demonstrated that the effect of large portions on energy intake was robust and sustained over periods as long as 11 days. This indicates that, when there is a continual abundance of food, regulatory mechanisms that affect energy intake cannot be depended on to halt overconsumption even after several days. The increased consumption associated with large portions was associated with decreased hunger and increased satiety, but these sensations were not sufficient to adjust intake. This study adds support to the suggestion that environmental influences such as portion size can cause dysregulation of energy intake that may contribute to the development of obesity.

B. Rolls, L. Roe, J. Meengs. The Effect of Large Portion Sizes on Energy Intake Is Sustained for 11 Days. Obes Res; 15:1535-1543 (June 2007). [Correspondence: Barbara J. Rolls, Department of Nutritional Sciences, Pennsylvania State University, 226 Henderson Building, University Park, PA 16802-6501. E-mail: bjr4@psu.edu.]


PARENT OVERWEIGHT PREDICTS DAUGHTERS’ INCREASE IN BMI AND DISINHIBITED OVEREATING FROM 5 TO 13 YEARS

Parents provide both genes and environments that may promote behaviors associated with excessive weight gain in children. Additionally, obesity runs in families, and having obese parents increases obesity risk in children. Parental weight status also predicts tracking of childhood overweight; an overweight child living in a family where one or more parent is overweight is likely to remain overweight throughout his or her childhood and into adolescence and adulthood. Accelerated weight gain in infancy and early childhood predicts later risk for overweight and obesity during childhood, adolescence, and adulthood. Several studies have addressed the ways in which parental overweight status may also influence the development of children’s eating behavior, dietary intake, and physical activity patterns.

Eating in the absence of hunger is a behavioral measure of disinhibited overeating and is characterized as the tendency to consume large amounts of palatable foods in a short period of time in a fashion that is not a response to hunger. Given its associations with weight gain and overweight, disinhibited eating has been proposed as a behavioral phenotype for obesity. Both genetic and environmental differences among families may shape the emergence of differences in eating styles such as disinhibited overeating. Additionally, overweight parents may be exhibiting distinctly different eating styles than normal weight parents and, in particular, may serve as models for their children’s disinhibited eating.

In this research, the researchers address whether having one or two overweight parents is predictive of accelerated weight gain and disinhibited eating during middle childhood and into adolescence, and whether disinhibited overeating aggregates within families. They hypothesized that overweight parents would report higher levels of disinhibited overeating than parents who are not overweight, and that, across middle childhood, daughters growing up in families with both parents overweight would exhibit greater increases in BMI, be more at risk for overweight, and have higher levels of disinhibited overeating than girls from families with one or neither parent overweight.

Participants were part of a longitudinal study of girls (N = 197) and their parents. Measured height and weight were used to calculate BMI [weight (kilograms)/height (meters)2]. Parents’ disinhibited eating behavior was assessed using the Eating Inventory. Girls’ disinhibited eating was assessed using a behavioral protocol to measure EAH. Girls were classified based on parental overweight at study entry into four groups: neither, mother only, father only, or both parents overweight.

Girls with both parents overweight had the most rapid increases in BMI from 5 years to 13 years of age; BMI increased most slowly among the neither parent overweight group, with intermediate increases in BMI among mother only and father only overweight groups. Daughters with both parents overweight at study entry were eight times more likely to be overweight at age 13, controlling for daughters’ weight at age 5. Girls with both parents overweight had higher levels of disinhibited eating across all ages than all other groups. Although girls in all parental weight status groups showed increases in disinhibited eating over time, girls with both parents overweight had larger increases in disinhibited eating over time compared with all other groups.

Results from this study revealed that during childhood and into early adolescence, girls developing in families differing in parental overweight had divergent trajectories of weight gain and disinhibited overeating. The data provided support for the primary hypothesis that, relative to girls without overweight parents, girls living in families with overweight parents had greater BMI increases across this period. Additionally, daughters’ BMI increase from 5 years to 13 years, as well as their risk for becoming overweight, was related to the number of overweight parents. Relative to girls with neither parent overweight, girls who had two overweight parents were 8.1 times more likely to be overweight at age 13. Overweight parents also reported higher levels of disinhibited eating than normal weight parents, and patterns of increase in girls’ disinhibited overeating during this same period of development also differed across parental weight status groups. At age 5, there were no systematic differences in BMI or disinhibited eating among girls, but diverging trajectories for BMI and disinhibited eating produced differences in both outcomes over time. Effects of parent overweight seem to be additive; girls with two overweight parents had the greatest gains in BMI and increases in disinhibited eating from 5 years to 13 years of age.

Mothers’, but not fathers’ disinhibited eating was associated with daughters’ disinhibited eating, but these links between mother’s and daughters’ disinhibited eating did not emerge until later childhood (ages 9, 11, and 13), perhaps because daughters’ disinhibited eating was lowest at age 5 and increased among all groups from age 5 to age 13. Although associations between daughters’ and mothers’ disinhibited eating have been previously reported, relationships between fathers’ and daughters’ have not been evaluated.

In conclusion, although no epidemiologic data are available on the prevalence of overweight specifically among parents in the United States, among 20- to 54-year-old adults, an age range that would include most parents, about two-thirds are overweight. These estimates suggest that the majority of children in the United States today are living in families with one or two overweight parents; only a small minority of children are growing up in families with neither parent overweight. These findings suggest that children in families with overweight parents are at elevated risk for obesity and that this demographic pattern may further accelerate the obesity epidemic. These findings indicate that, at least for girls, the effects of parental overweight on weight gain and disinhibited eating seem to be additive; girls growing up in families with at least one overweight parent showed accelerated patterns of weight gain from age 5 years to 13 years relative to girls with neither parent overweight and that girls with two overweight parents show even more substantial weight gain over the same period.

L. Francis, A. Ventura, M. Marini, et al. Parent Overweight Predicts Daughters' Increase in BMI and Disinhibited Overeating from 5 to 13 Years. Obes Res; 15:1544-1553 (June 2007). [Correspondence: Lori A. Francis, Department of Biobehavioral Health, 315 East Health and Human Development Building, The Pennsylvania State University, University Park, PA 16802. E-mail: lfrancis@psu.edu.]


BETWEEN MEAL CONSUMPTION OF SUGAR-SWEETENED BEVERAGES PLACES CHILDREN AT RISK OF BECOMING OVERWEIGHT

Overweight among children and adolescents have increased dramatically over the past two decades. This problem is reaching epidemic proportions and is a serious public health concern given that overweight often tracks into adulthood. A number of environmental, genetic, and social factors relating to diet have been associated as causes of overweight.

The aim of recent research was to examine the relationship between sugar-sweetened beverage consumption (for example--carbonated soft drinks and fruit drinks) between meals and the prevalence of overweight among preschoolers. Various characteristics--including prenatal and child factors (for example, parental weight and children’s birth weight and sex), demographic and socioeconomic factors (for example--maternal age, education, immigrant status, family type, and family income), and dietary factors (for example--energy intake, macronutrient intake, and total food group consumption)--related to sugar-sweetened beverage consumption between ages 2.5 years and 4.5 years, and to BMI at age 4.5 years, were analyzed to better understand the relationship between these factors in a population-based birth cohort of preschoolers from Québec, Canada.

The analyses were performed using data from the Longitudinal Study of Child Development in Québec (1998-2002). Data were collected when children were aged 2.5, 3.5, and 4.5 years from 2000 to 2002. The study followed a representative sample (n = 2,103) children born in 1998 in the Canadian province of Québec. The representative sample was chosen by a random selection of children born in each of the public health geographic areas. The study was based on face-to-face interviews and self-administered questionnaires addressed to children’s mothers and fathers. Of this group, 1549 children volunteered to take part in the nutrition study.

The nutrition assessment included a 24-hour dietary recall interview, a food frequency questionnaire (FFQ), and measurement of children’s height and weight. Overweight was defined as having a BMI at or above the 95th percentile on the US Centers for Disease Control and Prevention sex- and age-specific growth charts. A sugar-sweetened beverage was defined for this study as a drink that has added sugar. Sugar-sweetened beverages consisted of regular or nondiet carbonated drinks and fruit-flavored drinks listed on the FFQ.

Overall, 6.9% of children who were nonconsumers of sugar-sweetened beverages between meals between the ages of 2.5 years to 4.5 years were overweight at 4.5 years compared to 15.4% of regular consumers (four to six times or more per week) at ages 2.5 years, 3.5 years, and 4.5 years. According to multivariate analysis, sugar-sweetened beverage consumption between meals more than doubles the odds of being overweight when other important factors are considered in multivariate analysis. Children from families with insufficient income who consume sugar-sweetened beverages regularly between the ages of 2.5 years and 4.5 years are more than three times more likely to be overweight at age 4.5 years compared to nonconsuming children from sufficient income households.

Regular sugar-sweetened beverage consumption between meals places young children at risk of becoming overweight early in life.

L. Dubois, A. Farmer, M. Girard, et al. Regular Sugar-Sweetened Beverage Consumption between Meals Increases Risk of Overweight among Preschool-Aged Children. J. Am. Diet Assoc.; 107:924-934 (June 2007). [Correspondence: Lise Dubois, PhD, RD, Canada Research Chair in Nutrition and Population Health, Department of Epidemiology and Community Medicine, Faculty of Medicine, University of Ottawa Institute of Population Health, 1 Stewart St, Office 303, Ottawa ON, Canada K1N 6N5. E-mail: lise.dubois@uottawa.ca.]


NUTRIENT INTAKE DECLINES DURING ADOLESCENCE IN HAWAII

The dietary pattern of adolescents has changed rapidly during the past decade, including increased snacking and high-fat food intake, and greater frequency of eating foods outside of the home. Eating snacks between meals has contributed to higher carbohydrate intake, especially refined sugars. Furthermore, Dwyer and colleagues reported that the increased number of eating occasions is associated with higher total energy, carbohydrate, and added sugar intake and lower sodium intake.

There has been a shift in dietary trends among adolescents. These shifts increased intake of sweetened carbonated beverages, fruit drinks, sweetened drinks, salty snacks, and fried potatoes--and decreased intake of green beans, beef, and pork. And, nationally, milk consumption among adolescents has decreased.

The purpose of an investigation was to describe changes in dietary patterns of adolescent girls in Hawaii over a period of 2 years. This study was part of the Female Adolescent Maturation cohort study in Hawaii, which had exams 2 years apart. The girls were aged 9 years to 14 years at exam 1 and were aged 11 years to 16 years at exam 2. The total number of subjects was 151 girls.

Anthropometric measurements were taken during a clinic visit and included weight, height, and waist and hip circumferences. Girls also completed a validated physical activity questionnaire designed for adolescents. This questionnaire was sent to the subjects before each exam and was brought completed on the day of exam, and then checked by the project coordinator. Nutrient and food group intakes were obtained from a dietary record of 2 weekdays and 1 weekend day completed by the subjects with their parents’ assistance.

Girls at exams 1 and 2 had mean carbohydrate intakes of 233 g and 241 g respectively, and protein intakes of 67 g and 65 g, respectively. None of the carbohydrate intakes were below the Estimated Average Requirement (EAR) at exam 1 and only one girl was below at exam 2. Three percent of girls had protein intakes that were below the EAR at exam 1 whereas 9% were below at exam 2. For iron intakes, 3% of girls were below the EAR at exam 1 and 14% of girls were below at exam 2. Girls at exams 1 and 2 had mean calcium intakes of 733 mg and 11.4 g, respectively, and fiber intakes of 11.2 g and 11.4 g, respectively; lower than the Adequate Intake recommendation.

The percentage of energy from macronutrients in exams 1 and 2, respectively, was in range of the Appropriate Macronutrient Distribution Range for more than 70% of girls, but the mean percentage intake of saturated fat intake was higher than the recommended range for more than 65% of the girls at both exams 1 and 2. However, no significant differences were found in percent contribution of or in total intake of macronutrients between the two exams. More than half of girls (51% to 100%) did not consume the recommended number of Food Guide Pyramid Servings for any food group at either exam 1 or 2. A significant increase was found for sweetened carbonated beverage intake (from 130 g to 189 g; P < 0.05) and for added sugar intake (from 16 tsp to 18 tsp; P < 0.01) between exams 1 and 2, a level well above recommendations. As expected, mean body weight and mean BMI increased significantly between exams 1 and 2 (P < 0.05).

This data suggests high dietary intakes of dietary fat and sugar, and increasing intake of sweetened carbonated beverages and other high-sugar drinks during adolescence.

S. Kyung Lee, R. Novotny, Y. Daida, et al. Dietary Patterns of adolescent girls in Hawaii over a 2-Year Period. J. Am. Diet Assoc.; 107:956-961 (June 2007). [Correspondence: Soo Kyung Lee, PhD, Department of Human Nutrition, Food, and Animal Sciences, University of Hawaii at Manoa, 1955 East West Rd, Agricultural Sciences Building, Room 216, Honolulu, HI 96822. E-mail: sooklee@hawaii.edu].


NUTRIENT INTAKE IN CHILDREN WITH INTRACTABLE EPILEPSY

Epilepsy is a common, heterogeneous neurological disorder affecting 50 million people worldwide, more than half of which are children. About 70% have their seizures controlled with medications. The remainder develop intractable epilepsy and are at risk for side-effects from continued seizure activity, treatments, and possibly poor nutrition. Growth retardation has been reported in children with epilepsy and may be more common in children with intractable epilepsy and disabilities. The reason for the growth retardation is unclear and likely multifactorial. Frequent seizures and long post-ictal (postseizure) periods decrease the time a child is awake, and may lead to decreases in meal, food, and total energy intake.

Side-effects from antiepileptic drugs are common and increase with polytherapy, which is often required in the intractable epilepsy population. Side-effects from antiepileptic drugs may depress appetite, alter cognitive function, or interfere with nutrient absorption; all mechanisms for lowering food intake and nutrients such as iron and zinc.

Researchers set out to assess the pattern of nutrient intake of children with intractable epilepsy, compared with the intake patterns of healthy children from a nationally representative sample and with the Dietary Reference Intakes (DRI). Prepubertal children, 1 year to 8 years of age, having one or more seizures every 28 days, and for whom at least three appropriate antiepileptic drugs failed, were eligible for this cross-sectional study.

Caregivers maintained a daily seizure activity log, recording seizure type and frequency. For children with intractable epilepsy, dietary intake was assessed using 3-day weighed food records. The anthropometric examination for children with intractable epilepsy consisted of body weight, and stature.

The healthy children cohort used for the comparison group was from the National Health and Nutrition Examination Survey (NHANES) 2001-2002. In-home NHANES interviews were conducted by trained personnel to assess dietary intake for the past 24 hours by participant and caregiver recall.

Analyses were made with NHANES data to compare the dietary intake of children with intractable epilepsy to the usual intake of children in the United States. Researchers also compared the dietary intake of children with intractable epilepsy to the DRIs to evaluate the adequacy of their energy , macro-, and micronutrient intake. Energy intake was assessed with adjustments for height, body weight, and physical activity level, and expressed as a percentage of the estimated energy requirement at both the low active and sedentary levels for children. Physical activity level was generally estimated by the registered dietitian during an interview with the parents and described as: a) normal for age, b) low normal for age, or c) sedentary if the child was wheelchair-bound.

Forty-three children with intractable epilepsy, mean age = 4.7 years ± 2.2 years, had significantly lower intakes (P < 0.05) of total energy; protein; carbohydrate; fat; dietary fiber; vitamins A, E, B-6, and B12; riboflavin; niacin; folate; calcium; phosphorus; magnesium; zinc; copper; and selenium compared with healthy children. Thirty percent or more of the children with intractable epilepsy in both age groups had intakes below the Recommended Dietary Allowance or Adequate Intake for vitamins D, E, and K; folate; calcium; linoleic acid; and á-linolenic acid.

Healthcare professionals working with children with intractable epilepsy need to be aware of the pattern of decreased nutrient intake in this population.

S. Volpe, J. Schall, P. Gallagher, et al. Nutrient Intake of Children with Intractable Epilepsy Compared with Healthy Children. J. Am. Diet Assoc.; 107:1014-1018 (June 2007). [Correspondence: Stella L. Volpe, PhD, RD, Division of Biobehavioral and Health Sciences, School of Nursing, University of Pennsylvania, Nursing education Bldg, 418 Curie Blvd, Philadelphia, PA 19104-6096. E-mail: svolpe@nursing.upenn.edu.]


FRUITS AND VEGETABLES TAKEN FROM THE SCHOOL LUNCH LINE CAN PREDICT INTAKE

Increasing consumption of fruits and vegetables among children is a national health promotion goal because children consume inadequate amounts of fruits and vegetables, and deficient intake is related to a number of chronic diseases. Schools provide excellent opportunities for implementing interventions aimed at increasing fruit and vegetable consumption in children and there is sizable literature that describes intervention research on this topic. Any attempt to increase consumption, whether from a research- or a practice-based initiative, needs a method of evaluating the effectiveness of the intervention. To be credible, such evidence must be based upon a valid measure of dietary intake.

Identifying valid, reliable, feasible, and cost-effective methods for documenting dietary intake is a challenging task, particularly when observing young children. An earlier study showed evidence that the amount of fruits and vegetables taken on trays in a school cafeteria by fourth and fifth graders (ages 9 years to 13 years) is a valid, lower-cost proxy for fruits and vegetables eaten during lunch.

The purposes of a recent study were to: a) evaluate earlier findings that an assessment of fruits and vegetables taken is correlated with fruits and vegetable eaten, as measured through observation; b) evaluate whether the proxy of fruits and vegetables taken leads to similar conclusions about the success of an intervention, as does the criterion measure of fruits and vegetables eaten; and c) test whether the validity of fruits and vegetables taken differs by sex and holds with young children at the earliest (grade 1; ages 6 years to 7 years) school level.

This research was conducted as part of a school cafeteria-based randomized trial to increase fruit and vegetable consumption in elementary school children. Subjects were randomly selected from grade 1 and grade 3 in 26 schools in a large school district in the Twin Cities, MN, metropolitan area. Subjects were observed taking and eating their lunches at baseline. Schools were then randomized to treatment conditions and 13 schools received an intensive intervention over 2 school years. Of the 1668 students observed at baseline, 1168 were observed again at the end of the intervention.

The randomly selected students were identified with a colored name tag and were observed by trained staff during lunch. To assess foods taken, trained staff stood at the end of the serving line and, using prepared forms, documented all the foods taken on the lunch tray. Foods eaten at lunch were measured by having trained staff observe lunch intake. When the child finished eating, trays were taken to another area where observers measured and recorded the type and quantity of foods remaining on each tray.

Correlations between amounts of fruits and vegetables taken and eaten ranged from 0.74 to 0.96. The median correlation in grade 1 was the same--0.82--as in the combined sample. Food taken and food eaten as alternative response variables resulted in the same conclusions about the effects of intervention.

The hypothesis that food taken can be used as a proxy for consumption in future nutrition education research has been strengthened by this data.

C. Gray, L. Lytle, C. Perry, et al. Fruits and Vegetables Taken Can Serve as a Proxy Measure for Amounts Eaten in a School Lunch. J. Am. Diet Assoc.; 107:1019-1023 (June 2007). [Correspondence: Clifton Gray, PhD, Division of Epidemiology, University of Minnesota, 1300 S 2nd St, Minneapolis, MN 55454-1015. E-mail: gray_c@epihum.epi.umn.edu.]


CHRONIC DISEASE AND DIET IN KOREAN AMERICANS

Immigrant populations provide valuable information regarding the ways in which changes in environment, dietary intake, and lifestyle behavior affect healthy and disease status. Many studies of immigrants from Asian countries have reported that acculturation to Western living leads to changes in dietary patterns that are associated with a higher prevalence of CHD, cancers, and diabetes, as well as a lower prevalence of stomach cancer, infectious diseases, and tuberculosis.

The number of Korean immigrants in the United States increased dramatically after the passage of the 1965 Immigration and Nationality Act. More than 1 million Korean Americans, representing 0.4% of the total US population and 10.5% of all Asian immigrants, were living in the United States in 2000. The National Health Interview Survey 1992-1994 documented that a higher percentage of Korean Americans reported their health status as fair or poor compared with Japanese, Chinese, Filipino, Asian Indian, and Vietnamese subgroups.

There are distinct differences between Korean and US disease patterns, and between Korean and US dietary habits. Research regarding Korean Americans’ health status and diet has been limited to studies on cancer screening, health and health knowledge, and dietary practices. Identifying differences in dietary patterns and disease prevalence among Korean Americans can provide valuable information about the effects of immigration on dietary patterns and health risks. The purposes of a recent study were to examine the relationship of dietary patterns and length of residence in the United States, and to determine the association between dietary practice and disease prevalence by acculturation status.

A cross-sectional study was conducted from April 2000 to August 2000 of Korean Americans residing in Michigan using a mail survey. After exclusion, 497 men and women, aged 30 years to 87 years, were included in the final data analysis. The questionnaire contained demographic information (for example--age, sex, education, occupation, marital status, employment status, and length of residence in the United States), lifestyle criteria (for example--smoking and alcohol consumption), weight and height, self-reported health conditions, and a 93-item food frequency form. The semiquantitative 93-item FFQ for Korean Americans (KFFQ) was adapted from the National Health Information Survey Health Habit and History Questionnaire and the third National Health and Nutrition Examination Survey. Food intake was estimated using the frequency of consumption multiplied by the portion size of each food item on the KFFQ.

Chronic diseases reported most frequently by men and women, respectively, were hypertension, digestive diseases, arthritis, and diabetes. Length of residence in the United States (=15 years, 16 to 25 years, or = 26 years) was inversely associated with the prevalence of digestive diseases in men (P = 0.017) and women (P = 0.001), and positively with respiratory disease in men and thyroid disease in women (P < 0.05). Length of residence in the United States was inversely associated with intake of rice/rice dishes in both men (servings per week, P < 0.001) and women (P = 0.012). The prevalence of digestive diseases associated inversely with length of residence and positively with servings of rice/rice dishes consumed for Korean-American men. The age-adjusted odds ratio for digestive diseases was highest among men who had the shortest length of residence in the United States (=15 years) and greater consumption of rice/rice dishes (>2 servings per day) (odds ration 12.10; P=0.03).

Dietary changes of Korean-American immigrants in the United States over time were associated with changes in their chronic disease patterns.

E. Yang, H. Chung, W. Kim et al. Chronic Diseases and Dietary Changes in Relation to Korean Americans’ Length of Residence in the Untied States. J. Am. Diet Assoc.; 107:942-950 (June 2007). [Correspondence: Won O. Song, PhD, MPH, RD, Professor of Human Nutrition and Associate Dean, Room 135, G. M. Trout Bldg, Michigan State University, East Lansing, MI 48824-1224. E-mail: song@msu.edu.]


ASSESSING DIETARY INTAKE OF HISPANIC ADULTS WITH HIV

Weight loss and wasting are common problems experienced by people infected with the human immunodeficiency virus (HIV). Injection drug users accounted for 20% of all estimated HIV/acquired immunodeficiency syndrome cases in the United Sates at the end of year 2005. Drug abuse may contribute to this HIV-associated with loss. In addition to weight loss, micronutrient deficiencies are common. Some studies have proposed and demonstrated that micronutrient supplementation can slow the progression of HIV disease. Drug abuse is an important risk factor for HIV, specifically among Hispanics residing in the northeastern United States.

The most practical and economical method for collection of comprehensive dietary data in large epidemiologic studies is the FFQ. An FFQ collects less detail regarding specific foods consumed, cooking methods, and portion sizes than do 24-hour dietary recalls or 3-day diet records. The performance of FFQs in describing food consumption patterns and intake of individual nutrients has been evaluated extensively in European and US non-Hispanic white populations. However, little is known about the performance o FFQs in US minority populations. The current study was conducted among Hispanics living in the northeastern United States who are mainly of Puerto Rican origin.

Investigators used an FFQ that was previously developed for use among Hispanics living in Massachusetts. The subjects in this study were Hispanic, with and without HIV, many of whom had problems of drug abuse and homelessness. Given the likely instability of diet in this population, the best choice of dietary assessment method is not immediately clear. For this reason, researchers compared the most commonly used methods for dietary intake assessment: a 24-hour recall, a 3-day diet record, and an FFQ among drug-abusing Hispanics with and without HIV infection.

The data used in this cross-sectional analysis were collected as part of the BIENESTAR study. This study was designed to examine the effect of drug abuse on the nutritional status of Hispanics with HIV. Briefly, participants were recruited into one of three groups: HIV-infected drug abusers, HIV-noninfected drug abusers, and HIV-infected persons who do not use drugs (that is, nondrug abusers).

Bilingual Hispanic personnel conducted study interviews in Spanish. In this study, dietary information was collected from each participant using the three different dietary assessment methods mentioned above. A 24-hour dietary recall and an interviewer-administered FFQ were taken at the first baseline visit. Participants were then asked to keep a 3-day diet record during the week before the second baseline visit, about 10 days later. Complete instructions for maintaining a 3-day diet record were provided by the staff. The completed 3-day diet record was reviewed with the participant to ensure completeness during the second visit.

The 286 enrolled participants completed 282 FFQs, 142 3-day diet records, and 270 24-hour recalls. Energy-adjusted and deattenuated correlations between the FFQ and 3-day diet records ranged from 0.11 (carbohydrate) to 0.75 (caffeine). Twenty-seven of 33 nutrient intakes estimated by 3-day diet record were significantly lower than by FFQ (P< 0.05). Three-day diet records underestimated dietary intake relative to the FFQ and 24-hour recall methods. Fifty percent of records were not completed. Energy estimates from the FFQ and 24-hour recall were similar to each other.

The 24-hour recall gave higher mean dietary intake estimates, however, this would require multiple contacts with this difficult-to-reach population. The FFQ that was specifically designed for use with this population performed well in comparison to the other methods.

S. Sahni, J. Forrester, K. Tucker. Assessing Dietary Intake of Drug-Abusing Hispanic Adults with and without Human Immunodeficiency Virus Infection. J. Am. Diet Assoc.; 107:968-976 (June 2007). [Correspondence: Katherine L. Tucker, PhD, Dietary assessment and Epidemiology Research Program, Jean Mayer USDA HNRCA at Tufts University, 711 Washington St, Boston, MA 02111-15243. E-mail: Katherine.tucker@tufts.edu.]


NUTRITION ASSESSMENT OF HIV PATIENTS IN GHANA

The World Health Organization reports that HIV and acquired immunodeficiency syndrome (AIDS) complex as the number one cause of death in sub-Saharan Africa. Two-thirds of all infections and almost 80% of all HIV-related deaths have occurred there. As a consequence of this devastating epidemic, developmental gains by countries of sub-Saharan Africa during the past several decades have come to a halt.

Throughout Africa, HIV/AIDS is commonly referred to as "slim disease" because the combination of altered metabolism, decreased appetite, and malabsorption associated with wasting syndrome results in visible body weight loss. While a poor diet does not cause AIDS, it is the major contributor to impaired immune function observed throughout the world. Thus, a poor diet may accelerate the onset of AIDS after HIV infection creating a vicious cycle in which malnutrition, HIV infection, and additional opportunistic infections destroy the immune system, and death is imminent.

The nutritional status of HIV/AIDS patients in Ghana is not well documented. However, the typical West African dietary staples, including rice, yam, plantain, and cassava, generally do not meet the recommended dietary allowances for macronutrients and micronutrients. High-protein and energy-rich foods such as beans, groundnuts, and tropical plant oils, in addition to vitamin- and mineral-rich green leafy vegetables and fruits, are available throughout the continent, yet are either considered expensive or simply preferred less by the people. The purpose of a recent investigation was to evaluate the nutritional status of a small sample of HIV-seropositive individuals in Accra, Ghana, and to describe factors that may be associated with weight maintenance and health status after HIV diagnoses.

This descriptive, cross-sectional pilot study examined outpatients diagnosed HIV-seropositive (n=50) during the late spring of 2003. The eligibility criteria for participation included age 18 years to 65 years and self-report that the individual had HIV/AIDS. Demographic, anthropometric measurements, dietary intake, medical HIV history, food security, and food safety information were recorded for each participant by completing a questionnaire. The dietary assessment was made via a single 24-hour dietary recall conducted by one researcher, using food models and portion-size images to increase the accuracy of the recall from the previous 24 hours. BMI was calculated for each participant.

Results show that women participants had a higher mean BMI and maintained it through disease progression compared with men (P < 0.02). The majority of the participants cited cost as a barrier in purchasing adequate amounts of food (92%). Fruit and vegetable intake was low overall (<3 servings per day). The foods contributing most to daily energy intake were fried fish, white rice, kenkey, white bread, and fufu.

Health professionals must consider barriers to achieving optimal nutritional status in a cultural context when aiding in the fight against global HIV/AIDS.

K. Wiig, C. Smith. An Exploratory Investigation of Dietary Intake and Weight in Human Immunodeficiency Virus-Seropositive Individuals in Accra, Ghana. J. Am. Diet Assoc.; 107:1008-1013 (June 2007). [Correspondence: Chery Smith, PhD, MPH, RD, Associated Professor, University of Minnesota, Department of Food Science and Nutrition, 225 FScN, 1334 Eckles Ave, St Paul, MN 55108. E-mail: csmith@umn.edu.]


THE ECONOMIC COST OF HIGH-QUALITY DIETS

Energy density of foods refers to their energy content per unit weight (kcal/g). It is largely determined by the food’s water content because water adds to food weight, but not to food calories. Reducing dietary energy density by consuming more vegetables and fruit is a recommended approach to weight control.

Studies have shown that low-energy-density diets, with a higher proportion of vegetables and fruit, have a higher micronutrient content per kilocalorie. Conversely, the more energy-dense diets are not only more likely to be nutrient-poor, but have been associated with higher energy intakes overall. However, while the inverse relationship between dietary energy density and diet quality has been established, less attention has been paid to the relationship between dietary energy density and the monetary cost of the diet.

Energy-dense foods containing refined grains, added sugars, and added fats, are low-cost sources of dietary energy. In contrast, on a per-calorie basis, lean meats, fish, whole grains, vegetables, and fruit generally cost more. It is well-known that diet quality in the United States follows a sharp socioeconomic gradient. Additionally, previous European studies have consistently found that higher diet costs are associated with healthful eating.

Investigators hypothesized that low-energy density for the total diet (kcal/g) would be associated with higher diet costs. If higher-quality diets cost more (per kcal), then the ability to adopt more healthful eating habits is not only a behavioral issue, but also an economic issue. Clarifying the relationship between dietary energy density and diet costs has implications for some of the current strategies for health promotion.

The National Survey on Individual Food Consumption, conducted in 1999 by the French National Agency for Food Safety, was based on a nationally representative sample of 1985 French adults, aged 15 years to 92 years. All participants completed 7-day food records, aided by a photographic manual of portion sizes. Dietary data for 1474 participants (672 men, 802 women) were available for analysis. Food record data were matched to foods in a national nutrient database. Mean French national 1997 retail prices for 760 foods were obtained from marketing research. The remainder was obtained from the French National Institute of Statistics and from supermarket Websites.

Within each quintile of energy intakes, the more energy-dense diets were associated with lower diet quality and with lower diet costs (r2=0.38 to 0.44). In a regression model, the more energy-dense diets cost less, whereas low-energy-density diets cost substantially more, adjusting for energy intakes, sex, and age.

The finding that energy-dense diets cost less per 2000 kcal may help explain why the highest rates of obesity are observed among groups of limited economic means. This suggests that lasting improvements in diet quality may require both economic and behavioral interventions.

A. Drewnowski, P. Monsivais, M. Maillot, et al. Low-Energy-Density Diets are Associated with Higher Diet Quality and Higher Diet Costs in French Adults. J. Am. Diet Assoc.; 107:1028-1032 (June 2007). [Correspondence: Adam Drewnowski, PhD, 305 Raitt Hall, Box 353410, University of Washington, Seattle, WA 98195. E-mail: adamdrew@u.washington.edu.]


DEVELOPMENT OF A POLYAMINE DATABASE

Polyamines (putrescine, spermidine, and spermine) are organic compounds that are found in every living cell, where they are involved in numerous biochemical and physiological activities, including cell proliferation and differentiation. The metabolic requirement for polyamines is particularly high in rapidly growing tissues, such as during normal growth and development, and in tumors. Recent studies have suggested that reducing the amount of polyamines in cells may help to slow the cancer process. Whether foods that contribute to polyamine consumption affect cancer risk is also a topic ripe for exploration.

Until recently, it was believed that polyamines were derived exclusively from endogenous synthesis. It is now widely recognized that the polyamine body pool is maintained by three primary sources: synthesis within the body, production by microorganisms residing in the intestinal tract, and contribution from the diet. Therefore, polyamines in the diet are among the determinants of the total body polyamine pool and may be a particularly important consideration in assessing adequacy of diets during early development and in evaluating responses to pharmaceutical agents, such as inhibitors of polyamine synthesis, which are under study in clinical trials for cancer chemoprevention. Knowing the amount of polyamines that is typically provided by the diet is critical in interpreting the response to difluoromethylornithine in clinical trials testing the effect on cancer progression. Relatively little information on the polyamine content of foods is available.

The objectives of a recent project were to develop a polyamine database, with values for putrescine, spermidine, and spermine, and to link this database to an FFQ developed by the Fred Hutchinson Cancer Research Center. The development of a polyamine database linked to an FFQ will aid in the identification of foods with substantial polyamine concentrations and will allow an assessment of dietary polyamine intake.

The Fred Hutchinson Cancer Center FFQ is one of several FFQs used in major studies of diet and disease risk in the United States, including the sample examined in this report. An extensive search of the literature produced polyamine content data for approximately 117 of the 370 foods for which polyamine content data were needed. The polyamine levels of the 253 remaining food items were determined via imputation based on methods reported by Schakel and colleagues. Methods used for nutrient estimation of the database included: a) using values from a different, but similar food, b) calculating values from different forms of the same food, c) calculating values from other components in the same food, d) calculating values from household recipes, and e) assuming a zero value.

To test the newly developed database within the Fred Hutchinson Cancer Center FFQ programming, researchers examined data from a convenience sample of FFQs from the first 165 subjects enrolled in an ongoing multicenter, randomized, double-blind, placebo-controlled phase III chemoprevention trial in the United States, that is, examining the effect of difluoromethylornithine administration adenoma recurrence and relevant biomarkers. Participants recruited for this study were male and female, aged 40 years to 80 years, with a history of one or more resected adenomas. The average daily consumption of putrescine, spermidine, and spermine from the convenience sample, as provided by analysis of the Fred Hutchinson Cancer Center FFQs, were calculated. Polyamine values for each FFQ line item were also averaged to calculate the mean nmol/day of polyamine that each item contributed to the total intake of the convenience sample. The foods were ranked from highest to lowest dietary contributors of polyamines in the sample.

Of the foods from the database that were evaluated, fresh and frozen corn contain the highest levels of putrescine and spermidine, and green pea soup contains the highest concentration of spermine. Average daily polyamine intakes from the sample were 159, 133 nmol/day putrescine, 54,697 nmol/day spermidine, and 35,698 nmol/day spermine. Orange and grapefruit juices contributed the greatest amount of putrescine (44,441 nmol/day to the diet. Green peas contributed the greatest amount of spermidine (3283 nmol/day) and ground mean contributed the greatest amount of spermine (2186 nmol/day).

The development of this database linked to an FFQ provides a means of estimating polyamine intake and aids in research regarding polyamines and cancer.

C. Zoumas-Morse, C. Rock, E. Qunitana, et al. Development of a Polyamine Database for Assessing Dietary Intake. J. Am. Diet Assoc.; 107:1024-1027 (June 2006). [Correspondence: Christine Zoumas-Morse, MS, RD, University of California, San Diego, Moores Cancer Center, 3855 Health Sciences Dr, Dept 0901, La Jolla CA 92093-0901. E-mail: czoumasmorse@ucsd.edu.]


ABDOMINAL FAT AND RISK OF CORONARY HEART DISEASE IN PATIENTS WITH PERIPHERAL ARTERIAL DISEASE

Peripheral arterial disease (PAD) coexists with other manifestations of atherosclerotic disease at other locations in the vasculature. The risk of a fatal or nonfatal myocardial infarction or stroke is high in patients with PAD, whereas the incidence of complications associated with ischemia of the lower extremities is rather limited. The 5-year mortality due to cardiovascular diseases in PAD patients is approximately 30%. Moreover, these patients have a 3.1-fold increase in all-cause mortality compared with patients without PAD and a 6.6-fold increased risk of death from coronary artery disease.

Metabolic syndrome, the clustering of risk factors associated with central obesity, is prevalent in 58% of PAD patients and is associated with increased vascular damage. In general, patients with metabolic syndrome are at increased risk of developing type 2 diabetes and of cardiovascular morbidity and mortality. The high prevalence of metabolic syndrome in patients with PAD may contribute to the high incidence of cardiovascular events in these patients. Intra-abdominal fat is a major driver of insulin resistance, and therefore, plays an important role in the development of metabolic disorders, including hyperglycemia, hypertension, hypertriglyceridemia, and low HDL cholesterol. Furthermore, intra-abdominal fat accumulation causes dysregulation of adipocyte function, leading to oversecretion of tumor necrosis factor-alpha, free fatty acids, plasminogen activator inhibitor-1, interleukin-6, and growth factors, as well as hyposecretion of adiponectin, all of which may participate in the development of metabolic dysfunction. Patients with metabolic syndrome have a three- to fourfold increased risk of mortality due to coronary heart disease (CHD), and intra-abdominal fat is an important determinant of the risk of CHD, but the relative importance of intra-abdominal fat in patients with PAD is unknown. In addition, little is known about which of the various measurements of obesity show the strongest relation with the risk of CHD in patients with an arterial disease. Therefore, in the present study, the researchers investigated whether the presence of concomitant CHD can be explained by intra-abdominal fat accumulation and compared different measures of adiposity as predictors of CHD in patients with PAD.

Data were collected from patients enrolled in the Second Manifestations of ARTerial disease (SMART) study, an ongoing prospective cohort study of patients with manifest vascular disease or vascular risk factors at the University Medical Centre Utrecht. The current analysis includes 315 patients, mean age 59 years ± 10 years, who had PAD with (n = 79) or without (n = 236) CHD. Parameters of adiposity were measured, and intra-abdominal fat and subcutaneous fat were measured ultrasonographically. Metabolic syndrome was defined according to Adult Treatment Panel III.

The prevalence of metabolic syndrome was higher among patients with CHD (63%) than among patients without CHD (48%). All parameters of adiposity indicated more fat in patients with CHD, except for subcutaneous fat. Waist circumference was associated with 64% higher prevalence of CHD (confidence interval, 20% to 123%) per 1 standard deviation (SD) increase in waist circumference after adjustment for age and sex. The odds ratio for waist circumference remained virtually the same after additional adjustment for the components of the metabolic syndrome and smoking.

In this study, it is shown that each SD increase in waist circumference, an indirect indicator of intra-abdominal fat, was associated with a 61% increase in the risk of concomitant CHD in patients with PAD. Moreover, the metabolic syndrome was more prevalent among patients with CHD (63%). Patients with recently established atherosclerotic arterial disease are at high risk of developing another vascular complication in the same or another part of the vascular system.

In the present study, researchers found that the presence of CHD in patients with PAD was associated with abdominal fat accumulation, as evidenced by the strong association with waist circumference. Several factors may explain the increased cardiovascular risk of cardiovascular events associated with abdominal obesity. First, abdominal fat is associated with a number of metabolic disturbances, such as elevated blood pressure, hypertriglyceridemia, low serum HDL-cholesterol, and elevated plasma glucose, all established risk factors for the development of CHD. Second, visceral fat acts as an endocrine organ by secreting several hormones and cytokines, such as tumor necrosis factor-alpha, interleukin-6, plasminogen activator inhibitor-1, and adiponectin. These adipokines are directly or indirectly involved in the process of atherosclerosis, thus contributing to an increased cardiovascular risk. Metabolic syndrome, the clustering of risk factors associated with central obesity, is associated with advanced vascular damage in patients who already have clinical manifestations of vascular diseases, indicating that metabolic syndrome may lead to more generalized atherosclerosis. Indeed, metabolic syndrome is highly prevalent among patients with atherosclerosis.

The researchers concluded that, of the various measures of adiposity, waist circumference has the strongest association with CHD in patients with PAD. Reduction of abdominal adiposity may diminish the risk of vascular events in patients with PAD.

B. Brouwer, F. Visseren, R. Stolk, et al. for the SMART Study Group. Abdominal Fat and Risk of Coronary Heart Disease in Patients with Peripheral Arterial Disease. Obes Res; 15:1623-1630 (June 2007). [Correspondence: Y. van der Graaf, University Medical Center Utrecht, Room strat. 6.131, PO Box 85500, 3508 GA Utrecht, Netherlands. E-mail: y.vandergraaf@umcutrecht.nl.]


CAFFEINE INTAKE AND RISK OF HEART DISEASE MORTALITY IN OLDER PERSONS

Previous epidemiologic studies of the relation between caffeinated beverage intake and the risk of CVD have yielded conflicting results. It is possible that the conflict is due to differences between nonelderly and elderly persons. One study found that coffee drinking increased the risk in nonelderly participants and that the level of risk decreased with increasing age. In addition, elderly persons are more likely than are nonelderly persons to experience postprandial hypotension, which has been found to predict coronary events and total mortality. Caffeine has been found to induce a pressor effect, which involves increases in blood pressure (BP). The pressor effects become more pronounced with increasing age and could conceivably counteract the effects of hypotension.

It seems possible, therefore, that the consumption of caffeinated beverages could reduce the risk of CVD and heart disease mortality, especially in elderly persons with low BP. A prospective survival analysis was conducted to assess the risk of CVD and heart disease mortality at different levels of caffeinated beverage intake and at different levels of blood pressure.

Cox regression analyses were conducted for 426 CVD deaths that occurred during an 8.8-y follow-up in the prospective first National Health and Nutrition Examination Survey Epidemiologic Follow-up Study. The analysis involved 6594 participants aged 32 years to 86 years with no history of CVD at baseline.

Participants aged = 65 years with higher caffeinated beverage intake exhibited lower relative risk of CVD and heart disease mortality than did participants with lower caffeinated beverage intake. It was a dose-response protective effect: the relative risk (95% CI) for heart disease mortality was 1.00 (referent), 0.77 (0.54, 1.10), 0.68 (0.49, 0.94), and 0.47 (0.32, 0.69) for <0.5, 0.5 to 2, 2 to 4, and =4 servings/d, respectively (P for trend = 0.003). A similar protective effect was found for caffeine intake in mg/d. The protective effective was found only in participants who were not severely hypertensive. No significant protective effect was found in participants aged <65 years or in cerebrovascular disease mortality for those aged =65 years.

If these findings are confirmed, they may have important ramifications because caffeinated beverages are widely consumed, and heart disease is one of the leading causes of death in the elderly. The results do not allow investigators to conclude whether caffeine or the caffeinated beverages were responsible for the protective effect.

J. Greenberg, C. Dunbar, R. Schnoll, et al. Caffeinated Beverage Intake and the Risk of Heart Disease Mortality in the Elderly: A Prospective Analysis. Am. J. Clin. Nutr.; 85:392-398 (April 2007). [Correspondence: J. A. Greenberg, Department of Health and Nutrition Sciences, Brooklyn College of the City University of New York, 2900 Bedford Avenue, Brooklyn, NY 11210. E-mail: jamesg@brooklyn.cuny.edu.]

 

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