BMI Change During Puberty Is an Important Determinant of Adult Type 2 Diabetes Risk in Men

OBJECTIVE: The aim of this study was to determine the role of change in body mass index (BMI) during puberty, independent of childhood overweight, for risk of adult type 2 diabetes in men. STUDY DESIGN, POPULATION, AND OUTCOME: We included 36,176 men who had weight and height measured at age 8 and 20 years available from the BMI Epidemiology Study and the Conscription register. Information on type 2 diabetes (n = 1,777) was retrieved from the Swedish National Patient Register. Hazard ratios and 95% CIs were estimated by Cox regressions including birth year and country of birth as covariates. Because the assumption of proportional hazards was violated for the association between BMI change during puberty and type 2 diabetes, we split the follow-up time into early (≤55.7 years) and late (>55.7 years). RESULTS: Both childhood overweight and high BMI increase during puberty associated with risk of adult type 2 diabetes. Men with childhood overweight that normalized during puberty did not have significantly increased risk of type 2 diabetes [early type 2 diabetes 1.28 (0.89; 1.82); late type 2 diabetes 1.35 (0.97; 1.87)]. Men who developed overweight during puberty [early 4.67 (3.90; 5.58); late 2.85 (2.25; 3.61)] and men overweight throughout childhood and puberty [early 4.82 (3.84; 6.05); late 3.04 (2.27; 4.06)] had substantially increased risk of type 2 diabetes compared with men who were never overweight. CONCLUSION: BMI change during puberty is an important and childhood BMI a modest independent determinant of adult type 2 diabetes risk in men.