Long‐Term Weight Development in Women: A 15‐Year Follow‐up of the Effects of Pregnancy

Objective: The aim of this study was to evaluate how well prepregnancy BMI, gestational weight gain, and postpartum weight retention predict retention of weight 15 years later among parous women. Research Methods and Procedures: The Stockholm Pregnancy and Women's Nutrition (SPAWN) study is a long‐term follow‐up study of women who delivered children in 1984 to 1985 (n = 2342). The participants initially filled out questionnaires about their eating and exercise habits, social circumstances, etc. before, during, and at 1 year after pregnancy. Anthropometric data were also sampled. Fifteen years later, these women were invited to take part in the follow‐up study. Anthropometric measurements were collected, and similar questions were asked. Five hundred sixty‐three women participated in the SPAWN 15‐year follow‐up study. The sample was divided into groups to examine three presumably critical time periods: 1) overweight and normal weight before pregnancy; 2) low, intermediate, and high weight gainers during pregnancy; and 3) low, intermediate, and high weight retainers at 1 year after pregnancy. Results: The overweight women did not gain more weight during pregnancy or retain more weight at 1 year follow‐up. High weight gainers during pregnancy retained more weight at the 1‐year and the 15‐year follow‐ups. High weight retainers had gained more during pregnancy and retained it at the 15‐year follow‐up. Fifty‐six percent of the high weight gainers during pregnancy ended up in the high weight retainers group. Discussion: Women who are overweight before pregnancy do not have a higher risk of postpartum weight retention than normal weight women. Thus, it is not necessarily the initially overweight woman who should be the target or focus of weight control programs during or after pregnancy. Both high weight gainers and high weight retainers had higher BMI at the 15‐year follow‐up, although only 56% of the high weight gainers during pregnancy were also classified as high weight retainers at the 1‐year follow‐up. Weight retention at the end of the postpartum year predicts future overweight 15 years later.     

Sugar‐Added Beverages and Adolescent Weight Change

Objectives : The increase in consumption of sugar‐added beverages over recent decades may be partly responsible for the obesity epidemic among U.S. adolescents. Our aim was to evaluate the relationship between BMI changes and intakes of sugar‐added beverages, milk, fruit juices, and diet soda. Research Methods and Procedures : Our prospective cohort study included >10, 000 boys and girls participating in the U.S. Growing Up Today Study. The participants were 9 to 14 years old in 1996 and completed questionnaires in 1996, 1997, and 1998. We analyzed change in BMI (kilograms per meter squared) over two 1‐year periods among children who completed annual food frequency questionnaires assessing typical past year intakes. We studied beverage intakes during the year corresponding to each BMI change, and in separate models, we studied 1‐year changes in beverage intakes, adjusting for prior year intakes. Models included all beverages simultaneously; further models adjusted for total energy intake. Results : Consumption of sugar‐added beverages was associated with small BMI gains during the corresponding year (boys: +0.03 kg/m² per daily serving, p = 0.04; girls: +0.02 kg/m², p = 0.096). In models not assuming a linear dose‐response trend, girls who drank 1 serving/d of sugar‐added beverages gained more weight (+0.068, p = 0.02) than girls drinking none, as did girls drinking 2 servings/d (+0.09, p = 0.06) or 3+ servings/d (+0.08, p = 0.06). Analyses of year‐to‐year change in beverage intakes provided generally similar findings; boys who increased consumption of sugar‐added beverages from the prior year experienced weight gain (+0.04 kg/m² per additional daily serving, p = 0.01). Children who increased intakes by 2 or more servings/d from the prior year gained weight (boys: +0.14, p = 0.01; girls +0.10, p = 0.046). Further adjusting our models for total energy intake substantially reduced the estimated effects, which were no longer significant. Discussion : Consumption of sugar‐added beverages may contribute to weight gain among adolescents, probably due to their contribution to total energy intake, because adjustment for calories greatly attenuated the estimated associations.     

The Relationship Between Parent and Child Self‐Reported Adherence and Weight Loss

Objective: Better adherence to treatment strategies in family‐based behavioral weight control programs may lead to greater weight reduction and improved weight maintenance in youth. This study assessed the influence of child and parent self‐reported adherence to behavioral strategies on changes in 2‐year child and parent percentage overweight. Research Methods and Procedures: Participants included 8‐ to 12‐year‐old children in ≥ 85th BMI percentile and their parents from 110 families taking part in two family‐based randomized controlled weight control studies. This study examined whether self‐reported adherence to behavioral strategies measured at 24 months increased prediction of child and parent percentage overweight change through 24‐month follow‐up after accounting for other factors that may influence weight change. Results: Child adherence to weighing and to preplanning for celebrations where high‐fat foods are served and parent adherence to praising the child and modeling healthy eating habits predicted 24‐month child percentage overweight change (p < 0.001). Child adherence to recording food and calories and parent adherence to modeling healthy eating habits predicted 24‐month parent percentage overweight change (p < 0.001). In hierarchical regression models, child weighing and preplanning and parent modeling were significant (p < 0.01) incremental predictors (r² of 24.8%) of 24‐month child percentage overweight. Child recording and parent modeling were significant (p < 0.01) incremental predictors (r² of 14%) of parent 24‐month percentage overweight change. Discussion: Child and parent adherence to specific components of family‐based behavioral weight control treatment are independent predictors of long‐term child and parent percentage overweight change.     

Mediators of Weight Loss and Weight Loss Maintenance in Middle‐aged Women

Long‐term behavioral self‐regulation is the hallmark of successful weight control. We tested mediators of weight loss and weight loss maintenance in middle‐aged women who participated in a randomized controlled 12‐month weight management intervention. Overweight and obese women (N = 225, BMI = 31.3 ± 4.1 kg/m²) were randomly assigned to a control or a 1‐year group intervention designed to promote autonomous self‐regulation of body weight. Key exercise, eating behavior, and body image variables were assessed before and after the program, and tested as mediators of weight loss (12 months, 86% retention) and weight loss maintenance (24 months, 81% retention). Multiple mediation was employed and an intention‐to‐treat analysis conducted. Treatment effects were observed for all putative mediators (Effect size: 0.32–0.79, P < 0.01 vs. controls). Weight change was ?7.3 ± 5.9% (12‐month) and ?5.5 ± 5.0% (24‐month) in the intervention group and ?1.7 ± 5.0% and ?2.2 ± 7.5% in controls. Change in most psychosocial variables was associated with 12‐month weight change, but only flexible cognitive restraint (P < 0.01), disinhibition (P < 0.05), exercise self‐efficacy (P < 0.001), exercise intrinsic motivation (P < 0.01), and body dissatisfaction (P < 0.05) predicted 24‐month weight change. Lower emotional eating, increased flexible cognitive restraint, and fewer exercise barriers mediated 12‐month weight loss (R² = 0.31, P < 0.001; effect ratio: 0.37), but only flexible restraint and exercise self‐efficacy mediated 24‐month weight loss (R² = 0.17, P < 0.001; effect ratio: 0.89). This is the first study to evaluate self‐regulation mediators of weight loss and 2‐year weight loss maintenance, in a large sample of overweight women. Results show that lowering emotional eating and adopting a flexible dietary restraint pattern are critical for sustained weight loss. For long‐term success, interventions must also be effective in promoting exercise intrinsic motivation and self‐efficacy.     

Obesity in 70‐Year‐Old Subjects as a Risk Factor for 15‐Year Coronary Heart Disease Incidence

Objective: To investigate the role of obesity in general and waist circumference (WC) and BMI in particular as risk factors for 15‐year incidence of coronary heart disease (CHD) in the elderly. Research Methods and Procedures: This prospective study was based on 1597 (737 males and 860 females) 70‐year‐olds free from CHD and participants of three birth cohorts examined in 1971 to 1972 (Cohort I), 1976 to 1977 (Cohort II), and 1981 to 1982 (Cohort III) at Göteborg, Sweden. Fifteen‐year incidence of CHD (fatal and nonfatal) was ascertained from follow‐up examinations and registers. Relative risk (RR) for first ever CHD in reference to the lowest quartiles of WC and BMI was calculated from Cox regression. Results: In males, RRs for CHD in the highest WC and BMI quartiles were 1.36 [95% confidence interval (CI) 1.00 to 1.85] and 1.42 (95% CI 1.04 to 1.92), respectively, after adjustment for cohorts, smoking habits, diabetes, systolic blood pressure, and total cholesterol. In men, the risk associated with WC was independent of BMI. Neither WC nor BMI was related to CHD risk in females. After exclusion of first 5‐year all‐cause deaths, the adjusted RRs in the highest WC and BMI quartiles in males were 1.47 (95% CI 1.06 to 2.04) and 1.42 (1.04 to 1.92), respectively. In females, a significantly higher RR of 1.41 (95% CI 1.02 to 1.94) was observed in the second BMI quartile only after such exclusions. Discussion: WC, an indicator of both central and general obesity, appears to be a stronger predictor of CHD than BMI in elderly males, but in females, obesity was not a risk factor for CHD.     

Evidence of Shared Genetic Effects Between Pre‐ and Postobesity Epidemic BMI Levels

United States has experienced a widespread obesity epidemic. However, it is unclear whether the obesogenic environment has uncovered genes previously unimportant in adiposity or whether genes influencing obesity are the same before and after the obesity epidemic. The objective of this study was to test whether BMI pre‐ and postobesity epidemic would be controlled by shared genetic effects. A 25–30‐year follow‐up of parents and children who participated in the National Institutes of Health–National Heart, Lung, and Blood Institute Lipid Research Clinics (LRC) Princeton School Study, 1973–1976, were followed up in 1999–2004 in the Princeton Follow‐up Study (PFS). Heritability of BMI and genetic correlations between pre‐epidemic BMI and BMI z‐scores in adolescents and postobesity epidemic BMI were calculated. Even though they had similar ages, offspring had higher BMI in PFS than their parents in LRC (28.5 ± 6.6 vs. 26.1 ± 4.4, P < 0.0001). BMI measurements in offspring were strongly heritable (BMI_LRC: h² = 0.78 ± 0.17; BMI z‐score_LRC: h² = 0.61 ± 0.16; BMI_PFS: h² = 0.64 ± 0.16, all P ≤ 0.0001). Further, the change of BMI exhibited a high heritability (h² = 0.51 ± 0.18, P = 0.003). Bivariate analysis of BMI in LRC and PFS showed significant genetic correlation (0.70 ± 0.16, P = 0.005), whereas the environmental correlation was not significant (0.36 ± 0.17). Although the obesogenic environment may have changed between the 1970s and 2000s, many of the same genes are likely to be involved in establishing genetic susceptibility to obesity. Furthermore, shared genetic effects survive the period of the transition from adolescence to adulthood.     

Calcium and Dairy Intake and Measures of Obesity in Hyper‐ and Normocholesterolemic Children

Objective: Calcium intake has been inversely associated with body weight and body fatness in adults and, to a lesser extent, in children. Dairy intake has been inversely associated with metabolic syndrome in overweight but not normal‐weight adults. We assessed whether intakes of calcium and dairy foods were associated with measures of obesity in hypercholesterolemic (HC) and normocholesterolemic (non‐HC) children at baseline and over 1 year. Research Methods and Procedures: Non‐obese 4‐ to 10‐year‐old HC and non‐HC children (342) completed three 24‐hour dietary recalls and provided measures of relative weight (BMI and BMI z scores) and adiposity (sum of skinfolds, trunk skinfolds) at baseline, 3, 6, and 12 months. Cross‐sectional and longitudinal regression analyses, stratified by cholesterol risk status (HC vs. non‐HC) and age (4 to 6 years and 7 to 10 years) and adjusted for potential confounders, were conducted. Results: After adjusting for age, sex, energy intake, and percentage energy from fat, calcium intake was inversely associated with BMI, sum of skinfolds, and trunk skinfolds at baseline and over 1 year in the 7‐ to 10‐year‐old non‐HC children. Results from the regression models also indicated an inverse relation between intake of dairy foods and measures of obesity at baseline in these children. Calcium or dairy intake was not associated with measures of obesity in HC children or in the 4‐ to 6‐year‐old non‐HC children. Discussion: These results suggest a complex relation among intake of calcium and dairy foods, measures of obesity, age, and serum cholesterol in children. Older children without risk of metabolic syndrome may benefit most from increased calcium intake.     

Men Gain Additional Psychological Benefits by Adding Exercise to a Weight‐Loss Program

Objective: Adding exercise to a comprehensive weight‐loss program might not only attenuate any psychological distress associated with weight‐loss attempts but also may provide psychological benefits. This study examined whether a diet‐plus‐exercise weight‐loss program improved psychological outcomes more than a diet‐only weight‐loss program or an assessment‐only control group. Research Methods and Procedures: This study was part of a larger 1‐year randomized weight‐loss trial examining the effects of diet and exercise on cardiovascular disease risk factors in 264 overweight adults. Psychological measures specific to weight control (e.g., cognitive restraint, disinhibition, hunger, and body dissatisfaction) as well as traditional measures of psychological distress (e.g., symptoms of depression, anxiety, and stress) were obtained at baseline and 1 year. Results: Men and women in either weight‐loss program reported greater restraint, less disinhibition, and less hunger at 1 year than those in no program. Men in the diet‐plus‐exercise program experienced additional increases in restraint and decreases in hunger than did men in the diet‐only program. Women in the diet‐plus‐exercise program did not experience additional psychological benefits specific to weight control than those in the diet‐only program, despite increases in aerobic capacity. Discussion: The pattern seen for overweight men in the diet‐plus‐exercise program at 1 year—greater restraint, less disinhibition, and less hunger—is similar to the pattern seen in successful weight maintainers. These results underscore the need for innovative strategies that will enhance and sustain the pattern of psychological benefits specific to weight control associated with successful weight loss, especially for overweight women.     

Exercise‐Induced Reduction in Obesity and Insulin Resistance in Women: a Randomized Controlled Trial

Objectives : To determine the effects of equivalent diet‐ or exercise‐induced weight loss and exercise without weight loss on subcutaneous fat, visceral fat, and insulin sensitivity in obese women. Research Methods and Procedures : Fifty‐four premenopausal women with abdominal obesity [waist circumference 110.1 ± 5.8 cm (mean ± SD)] (BMI 31.3 ± 2.0 kg/m²) were randomly assigned to one of four groups: diet weight loss (n = 15), exercise weight loss (n = 17), exercise without weight loss (n = 12), and a weight‐stable control group (n = 10). All groups underwent a 14‐week intervention. Results : Body weight decreased by ～6.5% within both weight loss groups and was unchanged in the exercise without weight loss and control groups. In comparison with controls, cardiorespiratory fitness improved within the exercise groups only (p < 0.01). Reduction in total, abdominal, and abdominal subcutaneous fat within the exercise weight loss group was greater (p < 0.001) than within all other groups. The reduction in total and abdominal fat within the diet weight loss and exercise without weight loss groups was greater than within controls (p < 0.001) but not different from each other (p > 0.05). Visceral fat decreased within all treatment groups (p < 0.008), and these changes were not different from each other. In comparison with the control group, insulin sensitivity improved within the exercise weight loss group alone (p < 0.001). Discussion : Daily exercise without caloric restriction was associated with substantial reductions in total fat, abdominal fat, visceral fat, and insulin resistance in women. Exercise without weight loss was also associated with a substantial reduction in total and abdominal obesity.     

Gastric Bypass in a Low‐Income,Inner‐City Population: Eating Disturbances and Weight Loss

Objective: To examine the prevalence of eating disturbances and psychiatric disorders among extremely obese patients before and after gastric bypass surgery and to examine the relationship between these disturbances and weight outcomes. Research Methods and Procedures: Sixty‐five women patients (ages 19 to 67) with a mean BMI of 54.1 were assessed by semistructured psychiatric interview before surgery and by telephone interview after surgery (mean follow‐up: 16.4 months) to determine psychiatric status, eating disturbances, and weight and health‐related variables. Results: Patients lost a mean of 71% of their excess BMI, with significantly poorer weight loss outcomes among African Americans. Psychiatric disorders remained prevalent before (37%) and after (41%) surgery. In contrast, binge eating disorder dropped from 48% to 0%. Psychiatric diagnosis did not affect weight outcomes. Instead, more frequent preoperative binge eating, along with greater initial BMI, follow‐up length, and postoperative exercise, predicted greater BMI loss. Postsurgical health behaviors (exercise and smoking) and nocturnal eating episodes were also linked to weight loss. Exercise frequency increased and smoking frequency tended to decrease after surgery. Discussion: These findings indicated that eating and psychiatric disturbances did not inhibit weight loss after gastric bypass and should not contraindicate surgery. Prior binge eating, eliminated after surgery, predicted BMI loss and, thus, may have previously been a maintaining factor in the obesity of these patients. The association between health behaviors and outcome suggests possible targets for intervention to improve surgical results. Poorer outcomes among African Americans indicate that these patients should be closely monitored and supported after surgery.     

Predictors of Weight Loss in Adults with Topiramate‐Treated Epilepsy

Objective: We examined predictors of weight loss with topiramate, an anticonvulsant associated with weight loss in adults. Research Methods and Procedures: In this uncontrolled, prospective clinical trial, topiramate was added to existing anticonvulsants in adults (40 to 110 kg) with partial‐onset seizures. Primary measurements were change from baseline weight after 3 months and 1 year in patients completing 1 year of topiramate treatment (N = 38). Physiological and metabolic measures were analyzed for correlation with weight loss during topiramate treatment. Results: In patients who completed 1 year of topiramate treatment, baseline weight was reduced in 82% at 3 months and in 86% at 1 year. Mean body weight was reduced 3.0 kg (3.9% of baseline) at 3 months and 5.9 kg (7.3%) at 1 year. In obese patients [body mass index (BMI) ≥ 30 kg/m²], mean weight loss was 4.2 kg (4.3%) at 3 months and 10.9 kg (11.0%) at 1 year. Weight loss was primarily caused by reduction in body fat mass. For all patients, weight loss at 3 months correlated most strongly with reduced caloric intake (p = 0.02). At 1 year, caloric intake had returned to baseline levels; weight loss correlated most strongly with higher baseline BMI (p = 0.0007). Discussion: Our results suggest that weight loss occurs in most adults treated with topiramate and is sustained for at least 1 year. Reduced caloric intake may account, in part, for weight loss during early treatment. The pattern of weight loss differs according to baseline BMI, with obese patients experiencing greater weight loss during continued therapy.     

Increased exercise capacity after surgically induced weight loss in morbid obesity

Objective: To investigate the effects of surgically induced weight loss on exercise capacity in patients with morbid obesity (MO). Research Methods and Procedures: A prospective 1‐year follow‐up study was carried out, with patients being their own controls. A symptom‐limited cardiopulmonary exercise stress test was performed in 31 MO patients (BMI > 40 kg/m²) before and 1 year after undergoing bariatric surgery. Results: At 1 year after surgery, weight was reduced from 146 ± 33 to 95 ± 19 kg (p < 0.001), and BMI went from 51 ± 4 to 33 ± 6 kg/m² (p < 0.001). After weight loss, obese patients performed each workload with lower oxygen consumption, heart rate, systolic arterial pressure, and ventilatory volume (p < 0.001). This reduced energy expenditure allowed them to increase the duration of their effort test from 13.8 ± 3.8 to 21 ± 4.2 minutes (p < 0.001). Upon finishing the exercise, MO patients before surgery were able to reach only 83% of their age‐predicted maximal heart rate, and their respiratory exchange ratio was 0.87 ± 0.06. After weight loss, those values were 90% and 1 ± 0.08, respectively (p < 0.01). When we compared the peak O₂ pulse corrected by fat free mass before and after surgery, no significant differences between the groups were found. Discussion: After surgically induced weight loss, MO patients markedly improved their exercise capacity. This is due to the fact that they were able to perform the external work with lower energy expenditure and also to increase cardiovascular stress, optimizing the use of cardiac reserve. There were no differences in cardiac function before and after surgery.     

The Influence of Physical Activity,Socioeconomic Status,and Ethnicity on the Weight Status of Adolescents

Objective: This study examined the effects of physical activity, television viewing, video game play, socioeconomic status (SES), and ethnicity on body mass index (BMI). Research Methods and Procedures: The sample was 2389 adolescents, 10 to 16 years of age (12.7 ± 1.0 years); 1240 (52%) females and 1149 (48%) males; 77% white and 23% African American; from rural (77%) and urban (23%) settings. BMI and skinfolds were directly assessed. All other data were obtained from questionnaires. Results: Watching television on non‐school days was related to being overweight (p < 0.005). However, when BMI analyses were adjusted for ethnicity and SES, there were no significant effects of television viewing on BMI (p > 0.061). Increased hours of video game play enhanced the risk of being overweight for both genders when analyses were adjusted for ethnicity and SES (p < 0.019). In males, participation in as little as one high‐intensity physical activity 3 to 5 days a week decreased the ethnic‐ and SES‐adjusted relative risk of being overweight (RR = 0.646; CI: 0.427 to 0.977). For females, the ethnic‐ and SES‐adjusted relative risk for being overweight was not significantly altered by physical activity. The logistic analyses further indicated the influence of low SES and African American ethnicity overshadowed any direct effect of television or videos. Discussion: Because weight status of male adolescents appears to be more related to exercise habits than to television or video game habits, increased participation in high‐intensity exercise appears to be important. For females, neither videos nor exercise habits appear to be related to risk of being overweight. However, ethnicity and SES may be important factors that can influence body weight status, while television viewing may be of some importance. Thus, programs to reduce obesity in female adolescent should focus their efforts in lower SES communities.     

The Association of Restrained Eating With Weight Change Over Time in a Community‐Based Sample of Twins

We investigated the association of restrained eating with BMI and weight gain while controlling for the influence of genes and shared environment. Participants were 1,587 twins enrolled in the University of Washington Twin Registry (UWTR). Restrained eating was assessed by the Herman and Polivy Restraint Scale. Height and weight were self‐reported on two occasions. Analyses used generalized estimating equations or multiple linear regression techniques. Restraint Scale scores were positively associated with both BMI (adjusted β = 0.39 kg/m²; 95% confidence interval (CI) = 0.34–0.44; P < 0.001) and weight gain (adjusted β = 0.33 pounds; 95% CI = 0.17–0.49; P < 0.001). High Restraint Scale scorers had an adjusted mean BMI of 27.9 kg/m² (95% CI = 27.4–28.4) as compared to intermediate (mean = 25.5 kg/m²; 95% CI = 25.2–25.8) and low scorers (mean = 23.0 kg/m²; 95% CI = 22.7–23.3). In within‐pair analyses among 598 same‐sex twin pairs, the adjusted association between Restraint Scale scores and BMI persisted even when genetic and shared environmental factors were controlled for (adjusted β = 0.18; 95% CI = 0.12–0.24; P < 0.001), as did the association with weight gain (adjusted β = 0.37; 95% CI = 0.13–0.61; P = 0.003). In stratified analyses, dizygotic (DZ) twins differed more in BMI for a given difference in the Restraint Scale score than monozygotic (MZ) twins, for whom genetics are 100% controlled (adjusted β = 0.32; 95% CI = 0.20–0.44 vs. adjusted β = 0.10; 95% CI = 0.04–0.16; P = 0.001 for test of interaction). These data demonstrate that observed relationships between BMI, weight gain, and restrained eating, as assessed by the Restraint Scale, have a strong environmental influence and are not solely due to shared genetic factors.     

Body Fat and Fat‐Free Mass and All‐Cause Mortality

Objective: To investigate whether the association between BMI and all‐cause mortality could be disentangled into opposite effects of body fat and fat‐free mass (FFM). Research Methods and Procedures: All‐cause mortality was studied in the Danish follow‐up study “Diet, Cancer and Health” with 27, 178 men and 29, 875 women 50 to 64 years old recruited from 1993 to 1997. By the end of year 2001, the median follow‐up was 5.8 years, and 1851 had died. Body composition was assessed by bioelectrical impedance. Cox regression models were used to estimate the relationships among body fat mass index (body fat mass divided by height squared), FFM index (FFM divided by height squared), and mortality. All analyses were adjusted for smoking habits. Results: Men and women showed similar associations. J‐shaped associations were found between body fat mass index and mortality adjusted for FFM and smoking. The mortality rate ratios in the upper part of body fat mass were 1.12 per kg/m² (95% confidence interval: 1.07, 1.18) in men and 1.06 per kg/m² (95% confidence interval: 1.02, 1.10) in women. Reversed J‐shaped associations were found between FFM index and mortality with a tendency to level off for high values of FFM. Discussion: Our findings suggest that BMI represents joint but opposite associations of body fat and FFM with mortality. Both high body fat and low FFM are independent predictors of all‐cause mortality.     

Obesity and Medicare Expenditure: Accounting for Age‐Related Height Loss

To determine the relationship between BMI and Medicare expenditure for adults 65‐years and older and determine whether this relationship changes after accounting for misclassification due to age‐related height loss. Using a cross sectional study design, the relationship between BMI and fee‐for‐service Medicare expenditure was examined among beneficiaries who completed the Medicare Current Beneficiary Survey (MCBS) in 2002, were not enrolled in Medicare Health Maintenance Organization, had a self‐reported height and weight, and were 65 and older (n = 7,706). Subjects were classified as underweight, normal weight, overweight, obese (obese I), and severely obese (obese II/III). To adjust BMI for the artifactual increase associated with age‐related height loss, the reported height was transformed by adding the sex‐specific age‐associated height loss to the reported height in MCBS. The main outcome variable was total Medicare expenditure. There was a significant U‐shaped pattern between unadjusted BMI and Medicare expenditure: underweight $4,581 (P < 0.0003), normal weight $3,744 (P < 0.0000), overweight $3,115 (reference), obese I $3,686 (P < 0.0039), and obese II/III $4,386 (P < 0.0000). This pattern persisted after accounting for height loss: underweight $4,640 (P < 0.0000), normal weight $3,451 (P < 0.0507), overweight $3,165 (reference), obese I $3,915 (P < 0.0010), and obese II/III $4,385 (P < 0.0004) compared to overweight. In older adults, minimal cost is not found at “normal” BMI, but rather in overweight subjects with higher spending in the obese and underweight categories. Adjusting for loss‐of‐height with aging had little affect on cost estimates.     

Endothelial function and weight loss: Comparison of low‐carbohydrate and low‐fat diets

Objective: The effect of weight loss on obesity‐associated endothelial dysfunction is not clear because of conflicting data, demonstrating both improvement and no change in endothelial function after weight loss in obese subjects. A 2‐year prospective study (n = 121) was conducted to examine: (1) the effect of obesity and weight loss (either a low‐carbohydrate or and low‐fat diet) on flow mediated vasodilatation (FMD), a measure of endothelial function. Design and Methods: Participants reduced body weight by 7.1% ± 4.4%, 8.7% ± 6.8%, 7.1% ± 7.8%, and 4.1% ± 7.7% at 3, 6, 12, and 24 months, respectively with no significant differences between the low‐fat and low‐carbohydrate groups. Results: Endothelial function was inversely correlated with waist circumference, triglyceride level, and directly correlated with leptin in obese persons prior to weight loss. These weight losses did not confer any improvements in FMD. There were no differences between the low‐fat and low‐carbohydrate diets in FMD at any time point. At 6 months (r = 0.26, P = 0.04) and 1 year (r =0.28, P = 0.03), there were positive correlations between change in FMD and change in leptin but not at 2 years. Conclusion: There was no significant improvement in endothelial function after 7.1% ± 7.8% weight loss at 1 year and 4.1% ± 7.7% at 2 years, achieved by either a low carbohydrate or a low fat diet.     

Cut‐off Point of BMI and Obesity‐Related Comorbidities and Mortality in Middle‐Aged Koreans

Objective: The need for a lower BMI to classify overweight in Asian populations has been controversial. Using both disease and mortality outcomes, we investigated whether lower BMI cut‐off points are appropriate for identifying increased health risk in Koreans. Research Methods and Procedures: We conducted a cohort study among 773, 915 men and women from 30 to 59 years old with 8‐ to 10‐year follow‐up periods. Primary outcomes were change of obesity prevalence, obesity‐related disease incidence, and all‐cause mortality. Results: Prevalence of overweight (BMI of 25.0‐29.9) has steadily increased (1.3% annually), whereas obesity (BMI ≥ 30) showed a lower prevalence and only a slight increase (0.1%‐0.2% annually). Our study revealed that dose‐response relationships exist between obesity and related disease incidences (hypertension, type 2 diabetes, and hypercholesterolemia) beginning at lower BMI levels than previously reported. Compared with those in the healthy weight range, Koreans with a BMI ≥ 25 were not at greater risk of hypertension, type 2 diabetes, or hypercholesterolemia than has been reported for whites in similar studies. Obesity‐related all‐cause mortality also did not seem so different from that of whites. Discussion: Our findings did not support the use of a lower BMI cut‐off point for defining overweight in Koreans compared with whites for the purpose of identifying different risks. However, populations with BMI ≥ 25 are rapidly increasing and have substantial risks of diseases. To preempt the rapid increases in obesity and related health problems that are occurring in Western countries, Korea should consider using a BMI of 25 as an action point for obesity prevention and control interventions.     

Linkage and Genome‐wide Association Analysis of Obesity‐related Phenotypes: Association of Weight With the MGAT1 Gene

As major risk‐factors for diabetes and cardiovascular diseases, the genetic contribution to obesity‐related traits has been of interest for decades. Recently, a limited number of common genetic variants, which have replicated in different populations, have been identified. One approach to increase the statistical power in genetic mapping studies is to focus on populations with increased levels of linkage disequilibrium (LD) and reduced genetic diversity. We have performed joint linkage and genome‐wide association analyses for weight and BMI in 3,448 (linkage) and 3,925 (association) partly overlapping healthy individuals from five European populations. A total of four chromosomal regions (two for weight and two for BMI) showed suggestive linkage (lod >2.69) either in one of the populations or in the joint data. At the genome‐wide level (nominal P < 1.6 × 10^?7, Bonferroni‐adjusted P < 0.05) one single‐nucleotide polymorphism (SNP) (rs12517906) (nominal P = 7.3 × 10^?8) was associated with weight, whereas none with BMI. The SNP associated with weight is located close to MGAT1. The monoacylglycerol acyltransferase (MGAT) enzyme family is known to be involved in dietary fat absorption. There was no overlap between the linkage regions and the associated SNPs. Our results show that genetic effects influencing weight and BMI are shared across diverse European populations, even though some of these populations have experienced recent population bottlenecks and/or been affected by genetic drift. The analysis enabled us to identify a new candidate gene, MGAT1, associated with weight in women.     

Knee Structural Alteration and BMI: A Cross‐sectional Study

Objective: To describe the associations among BMI, knee cartilage morphology, and bone size in adults. Research Methods and Procedures: A cross‐sectional convenience sample of 372 male and female subjects (mean age, 45 years; range, 26 to 61 years) was studied. Knee articular cartilage defect score (0 to 4) and prevalence (defect score of ≥2), volume, and thickness, as well as bone surface area and/or volume, were determined at the patellar, tibial, and femoral sites using T1‐weighted fat‐saturation magnetic resonance imaging. Height, weight, BMI, and radiographic osteoarthritis were measured by standard protocols. Results: In multivariate analysis in the whole group, BMI was significantly associated with knee cartilage defect scores (β: +0.016/kg/m² to +0.083/kg/m², all p < 0.05) and prevalence (odds ratio: 1.05 to 1.12/kg/m², all p < 0.05 except for the lateral tibiofemoral compartment). In addition, BMI was negatively associated with patellar cartilage thickness only (β = ?0.021 mm/kg/m²; p = 0.039) and was positively associated with tibial bone area (medial: β = +7.1 mm²/kg/m², p = 0.001; lateral: β = +3.2 mm²/kg/m², p = 0.037). Those who were obese also had higher knee cartilage defect severity and prevalence and larger medial tibial bone area but no significant change in cartilage volume or thickness compared with those of normal weight. Discussion: This study suggests that knee cartilage defects and tibial bone enlargement are the main structural changes associated with increasing BMI particularly in women. Preventing these changes may prevent knee osteoarthritis in overweight and obese subjects.