Body Mass Index and Mortality according to Gender in a Community-Dwelling Elderly Population: The 3-Year Follow-up Findings from the Living Profiles of Older People Surveys in Korea

BACKGROUND: Body mass index is widely regarded as an important predictor of mortality. The purpose of this study was to investigate the relationship between body mass index and mortality and to compare community-dwelling elderly people in South Korea according to sex. METHODS: Data were collected from the 2008 and 2011 Living Profiles of Older People Surveys, which comprised 10,613 community-living South Korean men and women aged 65 years or older. The participants were stratified into five groups according to body mass index as defined by the World Health Organization guidelines. The sociodemographic characteristics of participants and mortality rates were compared across the body mass index groups. RESULTS: The highest survival rates were observed in men with a body mass index of 25.0–29.9 kg/m(2). A similar trend was observed in women, but it was not statistically significant. After adjusting for covariates, this association was also found in men across all BMI index groups, but not in women. CONCLUSION: This study supports previous findings that overweight or mild obesity is associated with the lowest mortality and suggests that the current categories of obesity require revision. Furthermore, the absence of statistically significant findings in the female cohort suggests that body mass index is not a suitable predictor of mortality in women and that an alternative is required.