Association of body shape index and body fat percentage with geriatric assessment outcomes.

Body mass index loses predictive value with aging, while alternative indices like a body shape index (ABSI) may better reflect body composition changes. This study explores the relationship between ABSI, body fat percentage (%BF), and geriatric assessment outcomes. This cross-sectional study included 439 patients in home healthcare services. Geriatric assessment covered Barthel activities of daily living, mini nutritional assessment - short form, Mini-Mental State Examination (MMSE), geriatric depression scale-15, clinical frailty scale, strength, assistance with walking, rising from a chair, climbing stairs, and falls, and visual analog scale. Data were analyzed; regression models assessed ABSI and %BF effects. The mean age of the patients was 80.4 ± 8.1 years, the mean ABSI score was 0.125 ± 0.021, and the mean %BF was 33.5 ± 5.1. ABSI scores varied significantly across MMSE categories, with higher scores in the early-stage dementia group In regression models, ABSI was positively associated with MMSE and the Barthel index but negatively associated with visual analog scale. %BF was negatively associated with mini nutritional assessment - short form and frailty. ABSI was positively linked to cognitive function and daily activities, whereas %BF was negatively associated with nutritional status, frailty, and pain. Given the growing older population, integrating ABSI and %BF into clinical practice could enhance geriatric assessments and improve health outcomes.