BACKGROUND Weight loss is recommended for overweight and obese individuals with type 2 diabetes based on short-term studies, but long-term effects on cardiovascular disease remain unknown. We examined whether intensive lifestyle intervention for weight loss decreased cardiovascular morbidity and mortality in overweight or obese adults with type 2 diabetes. METHODS We randomly assigned 5,145 overweight or obese individuals with type 2 diabetes recruited at 16 US centers to intensive lifestyle intervention (the intervention group), which promoted weight loss through decreased calorie intake and increased physical activity, or diabetes support and education (the control group). The primary outcome was the first post-randomization occurrence of a composite cardiovascular outcome (cardiovascular death, non-fatal myocardial infarction, non-fatal stroke, or hospitalized angina) over a planned maximum follow-up of 13.5 years. RESULTS The trial was stopped early based on a futility analysis when median follow-up was 9.6 years. Weight loss was greater in the intervention group than the control group throughout (8.6% vs. 0.7% at 1 year; 6.0% vs. 3.5% at study end). Intensive lifestyle intervention also produced greater reductions in hemoglobin A1c and greater initial improvements in fitness and all cardiovascular risk factors, except LDL cholesterol. The primary outcome occurred in 403 patients in the intervention group and in 418 in the control group (1.83/100 person-years and 1.92/100 person-years, respectively; hazard ratio 0.95; 95% CI 0.83 to 1.09, p=0.505). CONCLUSION In our study, intensive lifestyle intervention focused on weight loss did not reduce cardiovascular events in overweight or obese adults with type 2 diabetes. (Funded by the Department of Health and Human Services and others; ClinicalTrials.gov number, NCT00017953.)

OBJECTIVETo assess the relative impact of an intensive lifestyle intervention (ILI) on use and costs of health care within the Look AHEAD trial.RESEARCH DESIGN AND METHODSA total of 5,121 overweight or obese adults with type 2 diabetes were randomly assigned to an ILI that promoted weight loss or to a comparison condition of diabetes support and education (DSE). Use and costs of health-care services were recorded across an average of 10 years.RESULTSILI led to reductions in annual hospitalizations (11%, P = 0.004), hospital days (15%, P = 0.01), and number of medications (6%, P < 0.001), resulting in cost savings for hospitalization (10%, P = 0.04) and medication (7%, P < 0.001). ILI produced a mean relative per-person 10-year cost savings of $5,280 (95% CI 3,385–7,175); however, these were not evident among individuals with a history of cardiovascular disease.CONCLUSIONSCompared with DSE over 10 years, ILI participants had fewer hospitalizations, fewer medications, and lower health-care costs.

OBJECTIVEWe examined the effects of an intensive lifestyle intervention (ILI), compared with a diabetes support and education (DSE) control intervention, on long-term changes in depression symptoms, antidepressant medication (ADM) use, and health-related quality of life (HRQoL) in overweight/obese individuals with type 2 diabetes.RESEARCH DESIGN AND METHODSLook AHEAD was a multisite randomized controlled trial of 5,145 overweight/obese participants assigned to ILI (designed to produce weight loss) or DSE and followed for a median of 9.6 years. The Beck Depression Inventory (BDI) was administered at baseline, annually at years 1–4, and again at year 8. Mean BDI scores and incidence of BDI scores ≥10, indicative of likely mild or greater depression, were examined. Annually through year 10, participants reported their ADM use and completed the Medical Outcomes Study Short Form 36 (SF-36) questionnaire, which yields physical component summary (PCS) and mental component summary (MCS) scores.RESULTSILI significantly reduced the incidence of mild or greater depression symptoms (BDI scores ≥10) compared with DSE (hazard ratio [HR] = 0.85; 95% CI 0.75–0.97; P = 0.0145). Although SF-36 PCS scores worsened over time in both groups, ILI participants reported better physical function than DSE throughout the first 8 years (all P values <0.01). There were no significant differences between treatment arms in the proportion of participants who used ADMs or in SF-36 MCS scores.CONCLUSIONSILI for overweight/obese patients with type 2 diabetes may reduce the risk of developing clinically significant symptoms of depression and preserve physical HRQoL. These findings should be considered when evaluating the potential benefits of ILIs.

We examined the effects of metformin on diabetes prevention and the subgroups that benefited most over 15 years in the Diabetes Prevention Program (DPP) and its follow-up, the Diabetes Prevention Program Outcomes Study (DPPOS). RESEARCH DESIGN AND METHODS During the DPP (1996-2001), adults at high risk of developing diabetes were randomly assigned to masked placebo (n = 1,082) or metformin 850 mg twice daily (n = 1,073). Participants originally assigned to metformin continued to receive metformin, unmasked, in the DPPOS (2002-present). Ascertainment of diabetes development was based on fasting or 2-h glucose levels after an oral glucose tolerance test or on HbA 1c. Reduction in diabetes incidence with metformin was compared with placebo in subgroups by hazard ratio (HR) and rate differences (RDs). RESULTS During 15 years of postrandomization follow-up, metformin reduced the incidence (by HR) of diabetes compared to placebo by 17% or 36% based on glucose or HbA 1c levels, respectively. Metformin's effect on the development of glucose-defined diabetes was greater for women with a history of prior gestational diabetes mellitus (GDM) (HR 0.59, RD 24.57 cases/100 person-years) compared with parous women without GDM (HR 0.94, RD 20.38 cases/100 person-years [interaction P = 0.03 for HR, P = 0.01 for RD]). Metformin also had greater effects, by HR and RD, at higher baseline fasting glucose levels. With diabetes development based on HbA 1c , metformin was more effective in subjects with higher baseline HbA 1c by RD, with metformin RD 21.03 cases/100 person-years with baseline HbA 1c <6.0% (42 mmol/mol) and 23.88 cases/100 person-years with 6.0-6.4% (P = 0.0001). CONCLUSIONS Metformin reduces the development of diabetes over 15 years. The subsets that benefitted the most include subjects with higher baseline fasting glucose or HbA 1c and women with a history of GDM.

Across the Diabetes Prevention Program (DPP) follow-up, cumulative diabetes incidence remained lower in the lifestyle compared with the placebo and metformin randomized groups and could not be explained by weight. Collection of self-reported physical activity (PA) (yearly) with cross-sectional objective PA (in follow-up) allowed for examination of PA and its long-term impact on diabetes prevention. RESEARCH DESIGN AND METHODS Yearly self-reported PA and diabetes assessment and oral glucose tolerance test results (fasting glucose semiannually) were collected for 3,232 participants with one accelerometry assessment 11-13 years after randomization (n 5 1,793). Mixed models determined PA differences across treatment groups. The association between PA and diabetes incidence was examined using Cox proportional hazards models. RESULTS There was a 6% decrease (Cox proportional hazard ratio 0.94 [95% CI 0.92, 0.96]; P < 0.001) in diabetes incidence per 6 MET-h/week increase in time-dependent PA for the entire cohort over an average of 12 years (controlled for age, sex, baseline PA, and weight). The effect of PA was greater (12% decrease) among participants less active at baseline (<7.5 MET-h/week) (n 5 1,338) (0.88 [0.83, 0.93]; P < 0.0001), with stronger findings for lifestyle participants. Lifestyle had higher cumulative PA compared with metformin or placebo (P < 0.0001) and higher accelerometry total minutes per day measured during follow-up (P 5 0.001 and 0.047). All associations remained significant with the addition of weight in the models. CONCLUSIONS PA was inversely related to incident diabetes in the entire cohort across the study, with cross-sectional accelerometry results supporting these findings. This highlights the importance of PA within lifestyle intervention efforts designed to prevent diabetes and urges health care providers to consider both PA and weight when counseling high-risk patients.