Objective: The aim of this study is to assess the long-term effectiveness of a pragmatic community-based lifestyle intervention program on the prevention of type 2 diabetes and control of cardio-metabolic risk factors in Iran.
Research Design and Methods: In a community-based study, 3190 participants assigned to the control and 1929 participants assigned to the lifestyle intervention. Participants were aged ≥35 years and free of diabetes and cardiovascular diseases. The lifestyle intervention comprised of a single face-to-face interview between 1999 and 2001 imbedded in long-term ongoing community-based lifestyle intervention. Lifestyle intervention was focused on improving nutrition habits, physical activity, and smoking. Control group received usual care. Multivariable-adjusted regression models were used to compare the incidence of the type 2 diabetes and trend of risk factors between intervention groups.
Results: After median follow-up of 11.8 years, 632 new cases of type 2 diabetes were detected leading to incidence rate of 169.03 and 148.47 per 10000 person-years in control and intervention group, respectively. After accounting for the most important confounders, the lifestyle intervention was associated with 17% decrease in incidence of type 2 diabetes (incident rate ratio: 0.83[0.70, 0.99]). The lifestyle intervention was also associated with lower fasting plasma glucose, postprandial glucose, weight, BMI, waist circumference, triglycerides, prevalence of smoking, and higher high density lipoprotein.
Conclusions: A pragmatic community-based lifestyle intervention can prevent type 2 diabetes and reduce cardio-metabolic risk factors in long-term.

Long term effectiveness of a low-intensity community-based lifestyle intervention on type 2 diabetes incidence in Iran