Appendicular skeletal muscle mass and quality estimated by bioelectrical impedance analysis in the assessment of frailty syndrome risk in older individuals

BACKGROUND AND AIM: The rising aging index of many populations necessitates the continuous evolution of geriatric assessment methods, especially the ones used to identify frailty and the risk of frailty. An appropriately early diagnosis of adverse changes in skeletal muscles can reduce the risk of functional limitations in elderly persons. The aim of this study was to assess the correlation between the appendicular skeletal muscle mass and quality, estimated by the bioelectrical impedance analysis method, and the risk of prevalence of the pre-frailty state in elderly persons. METHODS: One-thousand-and-fifteen subjectively healthy persons aged 60–87 years were tested. Anthropometric measurements and physical fitness and activity measurements were carried out and the frailty phenotype was evaluated. Appendicular skeletal muscle mass was estimated using the bioelectrical impedance analysis method. Muscle quality was assessed through an index correcting strength relative to muscle mass and through the impedance phase angle. The correlation between the muscle mass and quality estimating parameters and the probability of identifying pre-frailty was checked using multiple logistic regression. RESULTS: The prevalence of pre-frailty was 38%. The pre-frail persons were found to have a significantly lower muscle mass and quality than the non-frail persons, with the difference in the case of the muscle quality index nearly twice larger than for the muscle mass index. A significant logit model was obtained for pre-frailty prevalence, which was strongly dependent on the appendicular skeletal muscle mass (adjusted odds ratio (OR): 0.43, 95% CI 0.36–0.52, p < 0.001) and functional quality (adjusted OR: 0.26, 95% CI 0.18–0.38, p < 0.001) and less on age (adjusted OR: 1.10, 95% CI 1.07–1.13, p < 0.001). CONCLUSION: The strong correlation between the frailty phenotype and appendicular skeletal muscle mass and functional quality suggests that the two variables should be included in routine geriatric assessment with regard to frailty.