Mortality risk in older men associated with changes in weight, lean mass, and fat mass

Objective: To evaluate risk of all-cause mortality associated with changes in body weight, total lean mass, and total fat mass in older men. Design: Longitudinal cohort study. Setting: Six U.S. clinical centers. Participants: Four thousand three hundred thirty-one ambulatory men aged 65 to 93 at baseline. Measurements: Repeated measurements of body weight and total lean and fat mass were taken using dual-energy X-ray absorptiometry 4.6 ± 0.4 years apart. Percentage changes in these measures were categorized as gain (+5%), loss (-5%), or stable (-5% to +5%). Deaths were verified centrally according to death certificate reviews, and proportional hazard models were used to estimate the risk of mortality. Results: After accounting for baseline lifestyle factors and medical conditions, a higher risk of mortality was found for men with weight loss (hazard rat (HR)=1.84, 95% confidence interval (CI)=1.50-2.26), total lean mass loss (HR=1.78, 95% CI=1.45-2.19), and total fat mass loss (HR=1.72, 95% CI=1.34-2.20) than for men who were stable for each body composition measure. Men with total fat mass gain had a slightly greater mortality risk (HR=1.29, 95% CI=0.99-1.67) than those who remained stable. These associations did not differ according to baseline age, obesity, or self-reported health status (P for interactions >.10), although self-reported weight loss intent altered mortality risks with total fat mass (P for interaction=.04) and total lean mass (P for interaction=.09) change. Conclusion: Older men who lost weight, total lean mass, or total fat mass had a higher risk of mortality than men who remained stable.