Incidence of type 2 diabetes and number of events attributable to abdominal obesity in China: A cohort study

BACKGROUND: The aim of the present study was to estimate the incidence of type 2 diabetes (T2D) and the number of diabetes events attributable to abdominal obesity in China. METHODS: A cohort study was conducted in a sample of 24,996 Chinese adults aged 35-74 years, with 19.9% of subjects lost to follow-up. Waist circumference (WC) was measured at baseline in 1998 and 2000-01, and abdominal obesity was defined as WC ≥ 90 cm in men and ≥80 cm in women. Information on incident diabetes was collected during follow-up in 2007-08. We estimated the number of T2D events attributed to abdominal obesity using confounder-adjusted population-attributable risk, incidence of diabetes, and the population size of China in 2010. RESULTS: After a mean follow-up of 8.0 years, the age-standardized incidence of T2D was 9.6 and 9.2 per 1000 person-years in men and women, respectively. Abdominal obesity accounted for 28.1% (95% confidence interval [CI] 14.8%, 40.5%) of incident diabetes among men and 41.2% (95% CI 28.3%, 52.6%) among women using the diagnostic criteria of abdominal obesity recommended by the International Diabetes Federation. We estimated that, in 2010, 2.4 (95% CI 1.5, 3.2) million diabetes events were attributable to abdominal obesity: 1.0 (95% CI 0.5, 1.4) million in men and 1.4 (95% CI 1.0, 1.8) million in women. CONCLUSIONS: Abdominal obesity is a major risk factor for T2D. Strengthening programs and initiatives for preventing and controlling obesity focusing on lifestyle changes should be a priority in the national strategy to reduce diabetes burden in China.