Association between duration of obesity and risk of non-insulin-dependent diabetes mellitus - The Sotetsu Study

The authors investigated the association between duration of obesity (ordin ary obesity as body mass index (BMI) (kg/m(2)) greater than or equal to 25. 0 and extreme obesity as BMI greater than or equal to 27.8) and the risk of diabetes mellitus. Male employees of a railway company, aged 30 years or o lder, observed for 10 years or more, free from serious disease conditions, with initial BMI <25.0, aged 30 years or more at the time diabetes was diag nosed, and with complete data, were examined by univariate and multivariate analyses (n = 1,598). Age-adjusted odds ratios for diabetes were significa ntly increased among males who were obese for 10-19.9 years and greater tha n or equal to 20 years (odds ratios = 2.10 and 2.84 for ordinary obesity an d 6.14 and 4.15 for extreme obesity, respectively). Additional adjustment f or current obesity, physical activity, smoking, drinking, family history, a nd observation period did not change the findings remarkably. In conclusion , greater than or equal to 10 years duration of ordinary obesity or greater than or equal to 1 year of extreme obesity was an important predictor for diabetes independent of age, current obesity, physical activity, smoking, d rinking, family history, and observation period.