Associations of functional ability with health-related behavior and body mass index among the elderly

The main purpose of this study was to determine whether functional ability among the elderly associates with body mass index (BMI) and health-related behavior. The secondary aim was to examine whether health behavior and BMI can be seen as mechanisms explaining sociodemographic disparities in functional ability. Cross-sectional biennial surveys from 1985 to 2001 were used to study 11,793 Finnish people aged 65-79 years. Associations of activities of daily living (ADL) with BMI, health behaviors (smoking, alcohol consumption, diet, physical activity), time period, previous occupation, marital status and certain diseases were tested using an ordinal regression model. Current and ex-smoking, heavy and non-alcohol use, unhealthy diet, physical inactivity and obesity were associated with inferior ADL. Alcohol consumption among men showed a U-shaped relation to functional ability. Most of the differences in ADL by occupation and marital status vanished after adjustment of multiple factors. The results showed clear associations of ADL with health-related behaviors and BMI when adjusted for multiple factors. The findings suggesting a U-shaped relation between ADL and alcohol consumption among men and the association between diet and ADL add to our previous knowledge of factors related to functional ability.