Predicting sarcopenia in community-dwelling older adults through comprehensive physical fitness tests.

Background: Sarcopenia is typically assessed through hand grip strength, walking speed, and chair stand tests. However, it has been inadequately examined in terms of other physical fitness (PF) components in community-dwelling older adults. Thus, in this study, we explored factors influencing the risk of sarcopenia in community-dwelling older adults. In addition, we analyzed the clinicodemographic characteristics of older adults with or without sarcopenia and investigated the effect of sex on their PF.

Methods: This cross-sectional study included 745 older adults from a community health promotion program in Taiwan. Their clinicodemographic characteristics were recorded. PF was assessed through various tests, such as hand grip strength evaluation, 8-foot up-and-go test (8-UGT), 2-min step test, and 6-m walk test. PF and factors influencing sarcopenia risk were compared between older adults with sarcopenia (sarcopenia group) and those without it (nonsarcopenia group). A logistic regression model was performed to identify key factors associated with sarcopenia. Its predictive performance was evaluated by calculating the area under the receiver operating characteristic curve (ROC) curve.

Results: Regardless of sex, the sarcopenia group performed worse in almost all components of PF-for example, upper and lower limb muscular strength and endurance, cardiopulmonary fitness, and balance-than did the nonsarcopenia group. However, for men, no significant between-group difference was observed in flexibility. The logistic regression model indicated age (odds ratio [OR]: 1.107), sex (OR: 2.881), Mini Nutritional Assessment-Short Form scores (OR: 0.690), and performance in 8-UGT (OR: 1.346) as factors influencing the risk of sarcopenia. The model exhibited excellent discriminative ability in predicting sarcopenia, as indicated by an area under the curve value of 0.867 (95% confidence interval: 0.827-0.906; p < 0.05).

Conclusion: Older adults without sarcopenia tend to outperform those with sarcopenia in almost all PF measures, regardless of sex. Older age, male sex, low Mini Nutritional Assessment-Short Form scores, and poor performance in 8-UGT are associated with a high risk of sarcopenia.