Objective: To investigate the independent effect of weight change in young adulthood on the risk of prevalent NIDDM among middle-aged Japanese men.
Research design and methods: A case-control study was carried out in 895 male employees aged > or = 30 years of a railway company located in the vicinity of Tokyo. Adjusted odds ratios (ORs) were calculated for prevalent diabetes in each category of weight change (obtained from subjects' medical records) in young adulthood and adulthood. Adjustment for current age, initial BMI, and weight change in each age stratum was performed by the Mantel-Haenszel method or multiple logistic regression analysis.
Results: Weight change between 20 years of age and the age at maximum weight was not associated with the risk of NIDDM. Weight gain between 20 and 25 years of age was significantly and positively associated with the risk of NIDDM (OR 3.87 for gains > or = 10.0 kg, 2.53 for gains of 5.0-9.9%, and 3.73 for gains > or = 10.0%). On the other hand, moderate weight gain after 30 years of age was significantly inversely associated with NIDDM (OR 0.44 for gains of 5.0-9.9 kg, 0.15 for gains of 10.0-19.9%, and 0.38 for gains of 20.0-29.9%).
Conclusions: Extreme weight gain between 20 and 25 years of age is a significant predictor of NIDDM, independent of current age, BMI at 20 years of age, and weight change within other age strata.