Can malnutrition, dietary habits, and diet quality be determinant factors in frailty, sarcopenia, low physical function, and depression in older adults?

The relationships between diet quality, malnutrition status and dietary intake and health problems such as frailty, sarcopenia, low physical function and depression, which are frequently observed in older individuals, are still unclear. This study aimed to investigate the associations between malnutrition, diet quality, and dietary intake and frailty, sarcopenia, low physical function, and depression in elderly individuals. The Edmonton Frailty Scale (EFS), Sarcopenia Rapid Screening Test (SARC-F), Katz Activities of Daily Living Scale (KATZ) for the Elderly, Geriatric Depression Scale (GDS), Mini Nutritional Assessment (MNA)-Short Form, and Mediterranean Diet Adherence Scales (MEDAS) were administered to all study participants (n = 695) to determine frailty, sarcopenia, physical status, depression status, nutritional status and adherence to the Mediterranean diet. The participants' dietary acid load was assessed via the potential renal acid load (PRAL) and net endogenous acid production (NEAP) indicators. Compared with men, women had significantly greater levels of frailty and sarcopenia (p < 0.05). Frailty and sarcopenia status were correlated with each other, and GDS scores increased significantly, whereas KATZ scores decreased as their severity increased (p < 0.05). MNA and MEDAS scores correlated with EFS (r = -0.508, p < 0.001; r = -0.084, p = 0.027, respectively), SARC-F (r = -0.358, p < 0.001; r = -0.126; p = 0.001, respectively), and GDS (r = -0.397, p < 0.001, r = -0,243, p < 0,001, respectively), whereas KATZ and MNA (r = 0,439) scores were found to be positively correlated with energy (r = 0,133) and protein (r = 0,119) intake (p < 0,05). As the PRAL score increased, the GDS (r = -0.082; p = 0.031), the SARC-F (r = -0.087; p = 0.022), and the EFS (r = -119, p = 0.002) decreased significantly. Each 1-unit increase in the MNA score caused decreases of 0.857, 0.431, and 1.201 units in the EFS, SARC-F, and GDS, respectively, and an increase of 0.190 units in the KATZ. Malnutrition status is positively associated with frailty, sarcopenia, low physical activity, and depression.