Relationship between different muscle mass indices and physical performance measures in Turkish older adults

Background Sarcopenia, characterized by the loss of skeletal muscle, is assessed using appendicular skeletal muscle mass indices (ASMI). Various international groups propose different ASMI thresholds for assessing sarcopenia. However, the optimal ASMI that correlates best with physical performance measures in older Turkish adults remains unexplored. This study aims to determine which ASMI is most closely associated with physical performance measures, particularly low handgrip strength (dynapenia), in Turkish older adults. Methods The study included 326 individuals aged 60 and above. Comprehensive geriatric assessments were conducted on all participants, along with anthropometric evaluations and body composition analyses. ASMI was calculated by adjusting height squared, weight, and body mass index (BMI). Physical performance was assessed through handgrip strength, gait speed, and the chair stand test. Results The mean age of the participants was 74 +/- 5.77 years, with 59.8% being women and 37.5% having dynapenia. Height-squared adjusted ASMI was not significantly associated with gait speed or the chair stand test. Weight-adjusted ASMI correlated with handgrip strength and gait speed but not with the chair stand test. Both height and weight-adjusted ASMI did not differ significantly between participants with and without dynapenia (p > 0.05). BMI-adjusted ASMI significantly correlated with all physical performance parameters (p < 0.05). Furthermore, in multivariate regression analysis, BMI-adjusted ASMI (OR = 0.028, 95% CI = 0.01-0.31, p = 0.006) was independently associated with dynapenia. Conclusion The study indicates that ASMI adjusted for BMI shows stronger correlations with all physical performance parameters and is independently associated with dynapenia. Utilizing ASMI adjusted for BMI may improve sarcopenia diagnosis in Turkish older adults.