This study aims to assess the effects of a community-based lifestyle intervention program on the incidence of type 2 diabetes (T2D). For this purpose, three communities in Tehran were chosen; one community received a face-to-face educational session embedded in a long-term communitywide lifestyle intervention aimed at supporting lifestyle changes. We followed up 9,204 participants (control: 5,739, intervention: 3,465) triennially from 1999 to 2015 (Waves 1-5). After a median follow-up of 3.5 years (wave 2), the risk of T2D was 30% lower in the intervention community as compared with two control communities by (Hazard-ratio: 0.70 [95% CI 0.53; 0.91]); however, the difference was not statistically significant in the following waves. After a median follow-up of 11.9 years (wave 5), there was a non-significant 6% reduction in the incidence of T2D in the intervention group as compared to the control group (Hazard-ratio: 0.94 [0.81, 1.08]). Moreover, after 11.9 years of follow-up, the intervention significantly improved the diet quality measured by the Dietary Approaches to Stop Hypertension concordance (DASH) score. Mean difference in DASH score in the intervention group versus control group was 0.2 [95% CI 0.1; 0.3]. In conclusion, the intervention prevented T2D by 30% in the short-term (3.5 years) but not long-term; however, effects on improvement of the diet maintained in the long-term. Registration: This study is registered at IRCT, a WHO primary registry (https ://irct.ir). The registration date 39 is 2008-10-29 and the IRCT registration number is IRCT138705301058N1. The burden of type 2 diabetes (T2D) is high and increasing in Low-and Middle-Income Countries (LMICs) like Iran 1. Iranians have a high risk of developing T2D with an incidence rate of the disease being 11 per 1,000 person-years 2. Given the high burden of T2D in Iran, there is an urgent need for effective prevention programs for T2D that can be implemented nationally. Community-wide strategies are vital to have a major impact on trends in raising the T2D epidemic 3-5. Several studies have assessed the effects of community-wide lifestyle interventions on the prevention of T2D. For this aim, community-wide interventions were delivered to a community living within a certain geographic area

Background The mechanisms linking adiposity to associated clinical conditions such as type 2 diabetes, cardiovascular disease, and related metabolic and inflammatory disturbances. are poorly understood.This study aimed to identify sex-specific direct and indirect effects of central and general adiposity on cardiovascular disease, mediated by cardiometabolic risk factors and how much is independent of these factors. Methods We analyzed data from the TLGS cohort study with 6280 participants aged ≥ 30 years, free of cardiovascular disease at baseline with a median follow-up of 13.9 years. The total effects were broken down into natural direct and indirect effects using a 2-stage regression model in the context of the survival model. We also calculated the proportion mediated by systolic blood pressure, total serum cholesterol, and fasting plasma glucose as mediators. Results There was no interaction between BMI and its mediators in the multiplicative scale (P > 0.05 for all). Blood pressure was the most important mediator for general (HRNIE: 1.11, 95% CI:1.17–1.24) and central obesity (HRNIE: 1.11, 95% CI:1.07–1.15) with proportion mediated of 60% and 36% respectively in the total population. The percentage mediated through all three metabolic risk factors together was 46% (95% confidence interval = 31%-75%) for overweight, 66% (45%-100%) for general obesity and 52% (39%-87%) for central obesity. Blood pressure was the most important mediator for overweight and central adiposity in male population with 29% and 36% proportion mediated respectively while in female population percentage mediated through all three metabolic risk factors together was 23% (95% confidence interval = 13%-50%) for overweight, 36% (21%-64%) for general obesity and 52% (39%-87%) for central obesity. Conclusions Metabolic mediators explain more than 60% of the adverse effects of high BMI on CVD in the male population. Also, managing these metabolic mediators in women does not effectively contribute to reducing CVD risks without decreasing weight.