The relationship between nutritional status and functional capacity, frailty, and depression in Turkish geriatric individuals: a cross-sectional study

Purpose: This study aimed to investigate the associations between nutritional status, functional capacity, frailty, and depression in older adults, and to evaluate how these parameters relate to body mass index.Materials and methods: A cross-sectional retrospective study was conducted by reviewing the records of patients who applied between January 01, 2024, and January 31, 2025, and included 417 older adults (mean age: 74.2±6.5 years; 61.1% female). Nutritional status was assessed using the Mini Nutritional Assessment, functional capacity with the Katz Index of Independence in Activities of Daily Living and Lawton-Brody Instrumental Activities of Daily Living Scale, frailty with the Clinical Frailty Scale. Physical performance was evaluated using the Timed Up and Go and Sit-to-Stand tests. Spearman's correlation coefficients and Kruskal-Wallis tests were used for statistical analysis.Results: Mini Nutritional Assessment scores were positively correlated with both basic (Katz, ρ=0.35; p<0.001) and instrumental (Lawton-Brody, ρ=0.32; p<0.001) activities of daily living. A significant negative correlation was observed between Mini Nutritional Assessment and Clinical Frailty Scale (ρ=-0.30; p<0.001). Mini Nutritional Assessment also showed weak but significant positive correlations with physical performance tests. A positive correlation was found between Body Mass İndex and Mini Nutritional Assessment (ρ=0.38; p<0.001); lower Body Mass İndex was associated with increased frailty (ρ=-0.21; p<0.001) and decreased performance in basic daily activities (Katz, ρ=0.16; p=0.001). However, the correlation between Mini Nutritional Assessment scores and Geriatric Depression Scale was weak and not statistically significant (ρ=-0.04, p=0.210).Conclusion: This study highlights the critical role of adequate nutrition in maintaining functional independence, reducing frailty, and supporting physical performance in older adults. Moreover, the relationship between nutritional status and depressive symptoms was found to be weak and did not reach statistical significance. Nutritional status should be a core component of geriatric assessments and addressed through multidisciplinary interventions.