[Association between body weight change during early and middle adulthood and the risk of type 2 diabetes in middle aged and elderly population].

To examine the association between weight changes during early and middle adulthood and the risk of type 2 diabetes mellitus in middle aged and elderly population. Based on the Guangzhou Biobank Cohort Study (GBCS), 28 736 residents aged ≥50 years were included in Guangzhou. Multivariate logistic regression was used to analyze the association between body weight changes during early or middle adulthood and age when the heaviest weight reaching the threshold on the risk of type 2 diabetes mellitus in middle age or elderly population. Adjustments on age, smoking, alcohol consumption, physical activity, education level, occupation, district of residence and body mass index ., were made. The mean age was 64.3 (standard deviation=6.7) years in men and 61.0 (standard deviation=7.0) years in women, with the prevalence rates of diabetes as 13.1% and 13.7% in men and women, respectively. Compared to those with stable body weight, the risk of diabetes increased with weight gain during early and middle adulthood in both men and women (both values for trend<0.01). Participants who gained more than 20 kg during early and middle adulthood were associated with the highest risk of diabetes in men (=2.83, 95%:1.99-4.02) and women (=3.13, 95%: 2.47-3.96). Compared to those who reached the highest weight at age 20, those who reaching the highest weight at 40 to 49 years were associated with the highest risk of diabetes, with being 5.32 (95%: 1.92-14.8) in men and 3.41 (95%: 2.49-4.67) in women, respectively. Weight loss in adulthood was associated with self-reported but not newly diagnosed diabetic cases in both middle and older aged men and women. Weight gain during early and middle adulthood may increase the risk of diabetes in middle and older aged population. The detrimental effect of obesity on diabetes might become significantly visible in the next decades.