Abstract
Sarcopenia is a critical health issue among older adults that leads to reduced muscle mass, strength decline, and impaired physical function. It is associated with falls, fractures, decreased quality of life, and increased mortality. Accurate diagnosis and management of sarcopenia are essential for the healthcare of the elderly. This study aimed to identify the key factors associated with sarcopenia in community-dwelling older adults in Korea and assess their relative importance in contributing to the development of diagnostic criteria tailored to the Korean population. A total of 581 individuals aged ≥60 years were recruited from welfare centers and nursing facilities. Sarcopenia was assessed using indicators such as handgrip strength (HGS), 5-time sit-to-stand, short physical performance battery (SPPB), and appendicular skeletal muscle. Multiple linear regression and receiver operating characteristic analyses were conducted to determine the relative importance and diagnostic accuracy of associated factors. The SPPB, HGS, age, body mass index, 30-second chair stand test, plantar flexion strength, and 2-minute walking test were significant factors related to sarcopenia. Among these, the SPPB score (β = -0.332, P < .001, area under the receiver operating characteristic curve = 0.786, cutoff = 9.5) and HGS (β = -0.294, P < .001, area under the receiver operating characteristic curve = 0.834, cutoff = 17.75) were the strongest predictors of sarcopenia, highlighting the importance of physical function in diagnosing sarcopenia. This study systematically evaluated key indicators for diagnosing sarcopenia and provided valuable data for establishing diagnostic criteria suitable for older adults in South Korea. These findings emphasize the necessity of incorporating physical function fitness assessments into the diagnosis of sarcopenia to improve early detection and intervention.