The relationship of body mass index and the functional status of community-dwelling female older people admitting to a geriatric outpatient clinic.

Abstract

The relationship of body mass index (BMI) with functional status differs in diversified geriatric population and various settings. In this study, we aimed to investigate whether BMI is related to functional status independent of age, nutritional status, multimorbidity, and polypharmacy in a group of Turkish community-dwelling female elderly. This study was conducted using a cross-sectional study design. Geriatric outpatient clinic of a university hospital. There were 438 female patients aged 60 years or older included in the analysis. Body mass indexes were calculated from weight (kg) divided by the square of height (m). Functional status was assessed with the evaluation of activities of daily living (ADL) and instrumental activities of daily living (IADL) scales. Diseases and drugs were determined after the evaluation of the patients with comprehensive geriatric assessment, physical examination, first-line biochemical tests, and using the patients' self-report and current medication lists. In total, 438 subjects comprised our study cohort. Mean age was 73.3 ± 6.9 years. Mean BMI was 27.8 ± 5.2 kg/m(2). Linear regression analysis revealed significant and independent association of lower BMI with higher ADL and IADL scores (p = 0.02, B = -0.10; p < 0.001, B = -0.17, respectively). ADL and IADL were significantly negatively correlated with BMI in subjects with normal nutrition (p = 0.03, r = -0.122; p = 0.001, r = -0.183) but not in subjects with malnutrition risk or malnutrition. We suggest that lower BMI is associated with better functional status in Turkish community-dwelling female older people. This association is prominent in the subjects with normal nutritional status. Our study recommends the need for further studies accounting for the nutritional status on the relationship between BMI and functionality in different populations and in different settings. It represents an important example for diversity in BMI-functionality relationship.