Endocrine Abstracts

Introduction: Studies show that a change in lifestyle can prevent or delay progression to diabetes in those with glucose intolerance. This study aimed to survey the effects of lifestyle changes on incidents of type II diabetes in Tehran adult population.

Materials and methods: This was a community based interventional study. Non-diabetic participants of Tehran Lipid and Glucose Study aged ≥20 years (6437 in control group and 2931 in intervention group) were followed for a mean duration of 3.5 years. The changes in lifestyle include an improvement in diet, increase in the level of physical activity and quitting of smoking. Mantel-Cox method was used to compare the incidents of diabetes between the groups. The Cox proportional hazard was used to obtain the proportional risk of incidents of diabetes in the intervention group.

Results: After an average period of 3.5 years follow up 58% of subjects completed the follow-up examination. The mean age of the population was 43±11 years and there were 41% males. The percentage of increase in weight, waist circumference, serum triglyceride and blood glucose in the intervention group was lower than controls (0.6 vs 3.3% for fasting glucose, 5.4 vs 10.6% for 2-h glucose, 1.2 vs 6.4% for triglyceride, 4.5 vs 5.7% for waist circumference (P<0.01) and 2.5 vs 3.2% for weight (P<0.01)). Incidence of diabetes was 12.2/1000 person-year in control group and 8.2/1000 person-year for case group. Relative risk of developing diabetes was significantly lower in the intervention groups after adjusting for confounding factors (hazard ratio 0.34, 95% CI: (0.25–0.47), P<0.001). Number needed to treat to prevent one case of diabetes was 25, 5.7, and 6.7 respectively for the whole population, those with impaired glucose tolerance, and those with body mass index ≥25 kg/m².

Conclusion: This study showed that after changes in lifestyle for 3.5 years, there was more than 65% reduction in incidents of diabetes in the Tehranian adult population.