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Background: Previous studies have shown that neighborhood factors are associated with obesity, but few studies have evaluated the association with weight control behaviors. This study aims to conduct a multi-level analysis to examine the relationship between neighborhood SES and weight-related health behaviors., Methods: In this ancillary study to Look AHEAD (Action for Health in Diabetes) a trial of long-term weight loss among individuals with type 2 diabetes, individual-level data on 1219 participants from 4 clinic sites at baseline were linked to neighborhood-level data at the tract level from the 2000 US Census and other databases. Neighborhood variables included SES (% living below the federal poverty level) and the availability of food stores, convenience stores, and restaurants. Dependent variables included BMI, eating patterns, weight control behaviors and resource use related to food and physical activity. Multi-level models were used to account for individual-level SES and potential confounders., Results: The availability of restaurants was related to several eating and weight control behaviors. Compared to their counterparts in neighborhoods with fewer restaurants, participants in neighborhoods with more restaurants were more likely to eat breakfast (prevalence Ratio [PR] 1.29 95% CI: 1.01-1.62) and lunch (PR = 1.19, 1.04-1.36) at non-fast food restaurants. They were less likely to be attempting weight loss (OR = 0.93, 0.89-0.97) but more likely to engage in weight control behaviors for food and physical activity, respectively, than those who lived in neighborhoods with fewer restaurants. In contrast, neighborhood SES had little association with weight control behaviors., Conclusion: In this selected group of weight loss trial participants, restaurant availability was associated with some weight control practices, but neighborhood SES was not. Future studies should give attention to other populations and to evaluating various aspects of the physical and social environment with weight control practices.

The researchers conducted this study to test the hypothesis that risk of type 2 diabetes is less following reductions in body size and central adiposity. The Diabetes Prevention Program (DPP) recruited and randomized individuals with impaired glucose tolerance to treatment with placebo, metformin, or lifestyle modification. Height, weight, waist circumference, and subcutaneous and visceral fat at L2-L3 and L4-L5 by computed tomography were measured at baseline and at 1 year. Cox proportional hazards models assessed by sex the effect of change in these variables over the 1st year of intervention upon development of diabetes over subsequent follow-up in a subset of 758 participants. Lifestyle reduced visceral fat at L2-L3 (men -24.3%, women -18.2%) and at L4-L5 (men -22.4%, women -17.8%), subcutaneous fat at L2-L3 (men -15.7%, women -11.4%) and at L4-L5 (men -16.7%, women -11.9%), weight (men -8.2%, women -7.8%), BMI (men -8.2%, women -7.8%), and waist circumference (men -7.5%, women -6.1%). Metformin reduced weight (-2.9%) and BMI (-2.9%) in men and subcutaneous fat (-3.6% at L2-L3 and -4.7% at L4-L5), weight (-3.3%), BMI (-3.3%), and waist circumference (-2.8%) in women. Decreased diabetes risk by lifestyle intervention was associated with reductions of body weight, BMI, and central body fat distribution after adjustment for age and self-reported ethnicity. Reduced diabetes risk with lifestyle intervention may have been through effects upon both overall body fat and central body fat but with metformin appeared to be independent of body fat.

The increasing prevalence of obesity is accompanied by an increasing prevalence of type 2 diabetes. Obesity not only increases the risk of developing type 2 diabetes but also compounds its health risks and complicates its management. The health benefits of weight loss and the efficacy of current weight loss strategies in obese persons with type 2 diabetes are evaluated. In addition, the article reviews the results of lifestyle intervention trials designed to reduce conversion to type 2 diabetes in at-risk individuals.

Unlabelled: OBJECTIVE; Weight loss improves glycemic control, lipid profiles, and blood pressure in patients with type 2 diabetes. However, successful long-term weight loss is difficult for these patients, particularly those treated with insulin. The aim of this study was to assess the effect of orlistat, a gastrointestinal lipase inhibitor, on weight loss, glycemic control, and cardiovascular risk factors in overweight or obese insulin-treated type 2 diabetic patients., Research Design and Methods: This study was a 1-year multicenter, randomized, double-blind, placebo-controlled trial of orlistat (120 mg three times a day) or placebo combined with a reduced-calorie diet in overweight or obese adults (BMI 28-40 kg/m(2)) with type 2 diabetes treated with insulin alone or combined with oral agents, but with suboptimal metabolic control (HbA(1c) 7.5-12.0%). Outcome measurements included changes in body weight, glycemic control, blood pressure, and serum lipids. RESULTS; After 1 year, the orlistat group lost significantly more weight (-3.89 +/- 0.3% of baseline body weight, means +/- SE) than the placebo group (-1.27 +/- 0.3%, P < 0.001). Orlistat treatment, compared with placebo, produced greater decreases in HbA(1c) (-0.62 +/- 0.08 vs. -0.27 +/- 0.08%, P = 0.002), fasting serum glucose (-1.63 +/- 0.3 vs. -1.08 +/- 0.3 mmol/l, P = 0.02), and the required doses of insulin and other diabetic medications. Orlistat also produced greater improvements than placebo in serum total cholesterol (P = 0.0002) and LDL cholesterol concentrations (P = 0.001) and LDL/HDL ratio (P = 0.01). CONCLUSIONS; Orlistat therapy produces clinically significant weight loss, with improvements in glycemic control and cardiovascular disease risk factors, in overweight or obese patients with type 2 diabetes who have suboptimal metabolic control with insulin therapy.

Inactivation of the melanocortin-4 receptor (MC4-R) by gene-targeting results in mice that develop maturity-onset obesity, hyperinsulinemia, and hyperglycemia. These phenotypes resemble common forms of human obesity, which are late-onset and frequently accompanied by NIDDM. It is not clear whether sequence variation of the MC4-R gene contributes to obesity in humans. Therefore, we examined the human MC4-R gene polymorphism in 190 individuals ascertained on obesity status. Three allelic variants were identified, including two novel ones, Thr112Met and Ile137Thr. To analyze possible functional alterations, the variants were cloned and expressed in vitro and compared with the wild-type receptor. One of the novel variants, Ile137Thr, identified in an extremely obese proband (BMI 57), was found to be severely impaired in ligand binding and signaling, raising the possibility that it may contribute to development of obesity. Furthermore, our results also suggest that sequence polymorphism in the MC4-R coding region is unlikely to be a common cause of obesity in the population studied, given the low frequency of functionally significant mutations.

Recently, several articles appearing in the diabetes literature have suggested that many investigators are unclear about a number of issues involving the use of areas under the curve (AUCs). This prompted us to reconsider issues in the calculation, use, meaning, and presentation of AUCs. We discuss five issues: 1) What is a curve and an area? 2) How should one graphically present a group's curve? 3) How should one calculate AUCs? 4) Should one subtract baseline values from outcome values before calculating AUCs? And 5) are AUCs the best way to combine multiple readings into a single index?

Diabetes mellitus is more prevalent in the American Black population than in the White population. The prevalence is increasing in Blacks, and there is evidence that it is accompanied by a greater severity of diabetic complications. In addition, mortality figures are higher in Blacks, and Black women are more seriously affected than Black men. Although the reasons for this are unclear, some factors stand out as important. These include obesity, socioeconomic status, and genetics. Obesity is a severe problem in Blacks, particularly in women. Both the degree and the distribution of fat may contribute greatly to the prevalence of diabetes in Blacks. Although the prevalence of obesity is higher in the poor economic groups, multivariate analysis suggests that poverty cannot explain all of the excess obesity that occurs in the Black population. More research is needed into a possible genetic predisposition of Blacks to obesity and diabetes and into the interrelationship between the two conditions in this racial group.

Intentional weight loss has been shown to increase bone loss short term but the long-term effects are not known. Data from the Look AHEAD clinical trial shows that a long term intentional weight loss intervention was associated with greater bone loss at the hip in men.PurposeIntentional weight loss has been shown to increase bone loss short term and increase frailty fracture risk, but the long-term effects on bone mineral density (BMD) are not known.MethodsData from a subgroup from the Look AHEAD (LA) multicenter, randomized clinical trial was used to evaluate whether a long term intentional weight loss intervention would increase bone loss. In a preplanned substudy, BMD was assessed at 5 of the 16 LA clinical centers using dual-energy X-ray absorptiometry at baseline, year 8, and the observational visit 12.6-16.3 years after randomization (year 12-16).ResultsAt year 8, bone density loss (%) was greater in the Intensive Lifestyle Intervention (ILI) group compared with the control group (DSE) for the femoral neck (p = 0.0122) but this finding was not observed at the year 12-16 visit. In analyses stratified by gender, bone density loss (%) was greater at the total hip for men in the ILI group than the DSE group at both the year 8 and year 12-16 visits (year 8 p = 0.0263 and year 12-16 p = 0.0062). This finding was not observed among women.ConclusionLong term intentional weight loss was associated with greater bone loss at the hip in men. These results taken with the previously published Look AHEAD data from the entire clinical trial showing increased frailty fracture risk with weight loss in the ILI group suggest that when intentional weight loss is planned, consideration of bone density preservation and fracture prevention strategies is warranted.Trial registrationClinicaltrials.gov Identifier: NCT00017953. June 21, 2001.