Associations of physical activity and body mass index with activities of daily living in older adults.

Research reports about the associations of leisure-time physical activity (LPA) and Body Mass Index (BMI) with activities of daily living (ADL)- or instrumental activities of daily living (IADL)-dependent disability in older adults are inconclusive. Data were obtained from the 2000 Missouri Older Adult Needs Assessment Survey. Logistic regression was used to examine the associations of LPA and BMI with ADL- or IADL-dependent disability, while controlling for factors known to be associated with LPA, BMI, ADL and IADL. ADL- or IADL-dependency decreased with LPA and increased with BMI regardless of each other's level, presence of functional limitation, education, gender, race-ethnicity, and health care coverage. Physically active individuals were less likely than inactive ones to be ADL- or IADL-dependent. BMI was modestly associated with ADL- or IADL-dependency and this relationship was confounded by LPA. If confirmed by well designed longitudinal studies, LPA and BMI independent associations with ADL- or IADL-dependent disability lends supports to a strategy for improving older adult quality of life through improved physical activity. Etiological studies on the associations between risk factors and quality of life outcomes in older adults should consider the joint confounding effect of LPA and BMI.