Association Between Sarcopenia and Frailty Transition in Chinese Older Adults: A Multistate Markov Model Study.

OBJECTIVES

Sarcopenia and frailty are closely linked geriatric syndromes, but how sarcopenia is associated with frailty's dynamic progression remains unclear. This study examined the association between sarcopenia and multistate frailty transitions in Chinese older adults.

DESIGN

A longitudinal study.

SETTING AND

PARTICIPANTS

This study is based on data from 4 waves (2011-2018) of the China Health and Retirement Longitudinal Study (CHARLS), including 4621 adults aged ≥60 years.

METHODS

Frailty status was classified as robust, prefrailty, or frailty using a 35-item frailty index. Sarcopenia was defined as nonsarcopenia, possible sarcopenia and confirmed sarcopenia according to Asian Working Group for Sarcopenia 2019 (AWGS 2019) criteria. A continuous-time multistate Markov model estimated transition intensities and probabilities across frailty states. Hazard ratios (HRs) were obtained from models sequentially adjusted for related factors to quantify the associations between sarcopenia and specific frailty transitions.

RESULTS

Among 4621 participants (mean age 67.3 years; 48.2% female), substantial transitions were observed between frailty states over 7 years of follow-up, with prefrailty being the most prevalent and dynamic state. Compared with nonsarcopenia, the HRs (95% CI) for confirmed sarcopenia were 1.29 (1.05, 1.57) for transitioning from robust to prefrailty and 1.20 (1.00, 1.43) for transitioning from prefrailty to frailty. Similar results were observed for possible sarcopenia. Among the 3 sarcopenia components, low muscle strength showed the strongest association with transitions indicating frailty deterioration, followed by low physical performance.

CONCLUSIONS AND IMPLICATIONS: Sarcopenia, regardless of severity, was associated with frailty progression in Chinese older adults, thereby identifying it as a key factor linked to frailty progression. These findings support early screening and targeted interventions to facilitate healthy aging.