Effects of body mass index and weight change on mortality in older men with impaired glucose regulation

Abstract Objectives To assess the effect of baseline body mass index (BMI) status and weight change on mortality in older men with impaired glucose regulation (IGR). Methods Eight hundred eighty-five men with IGR aged 60 to 90 were included. Baseline and endpoint weight were measured. All-cause and cardiovascular mortality were observed during a median follow-up period of 10 years. Multivariate Cox regressions were used to estimate associations between BMI, weight change and mortality. Results Relative to normal weight, overweight was associated with lower all-cause mortality (hazard ratios, HRs [95% confidence interval, 95% CI]: 0.57 [0.41, 0.78]) and cardiovascular mortality (0.52 [0.29, 0.93]), whereas obesity did not significantly decrease or increase the mortality risk. Furthermore, compared to weight stability, all types of weight change led to increased mortality risk, except small weight gain. Specifically, after adjustment for covariates and the initial weight, the HRs (95% CI) of large weight loss were 1.64 (1.15, 2.34) for all-cause mortality and 1.85 (1.10, 3.14) for cardiovascular mortality, and the HRs (95% CI) of large weight gain were 1.55 (1.01, 2.40) for all-cause mortality and 2.11 (1.04, 4.30) for cardiovascular mortality. Similar associations were observed when weight change was redefined in sensitivity analyses. Conclusions Both BMI at baseline and weight change have independent U-shaped associations with all-cause and cardiovascular mortality among older men with IGR. The present study suggests that older men with IGR may ensure their best survival by being overweight at baseline or by maintaining their weight regardless of their baseline weight status.