Survival in older men may benefit from being slightly overweight and centrally obese-a 5-year follow-up study in 4,000 older adults using DXA

Abstract

BackgroundWhether overweight in old age is hazardous remains controversial. Body mass index (BMI) overestimates adiposity and fails to measure central adiposity. We used dual-energy X-ray absorptiometry (DXA) to measure adiposity and hypothesized that overall adiposity, distribution of adiposity, and muscle mass might individually affect survival.MethodsWe recruited 2000 men and 2000 women aged 65 years or older. Baseline BMI, waist-hip ratio (WHR), body fat index (BFI = total body fat/height square), relative truncal fat (RTF = trunk fat/total body fat), and body muscle mass index (BMMI = total body muscle mass/height square) were measured. Mortality was ascertained by death registry after 63.3 (median) months.ResultsTwo hundred and forty-two men and 78 women died. In men, mortality hazard ratio (HR) decreased consistently by 0.85 (p