Probable respiratory sarcopenia and 9-year mortality in community-dwelling older adults: the first longitudinal evidence from the CHARLS

a position paper by the Japanese Working Group for Respiratory Sarcopenia (JWGRS). However, the clinical values of probable RS remain unclear. Therefore, we conducted a longitudinal study to determine its impacts on short- and long-term all-cause mortality. Our data were extracted from the China Health and Retirement Longitudinal Study. A total of 5,006 participants were selected as a cohort in 2011, and followed up until 2020. According to the JWGRS, probable RS was defined as a coexistence of low respiratory muscle strength and low appendicular skeletal muscles (ASM) mass. Hazard ratios (HRs) for all-cause mortality and cause-specific mortality were calculated through Cox regression analyses. After an average of 9 years of follow up, 1,176 of the 5,006 participants (23.49%) died. Cox proportional hazard regression showed that low ASM mass (HR = 1.24, 95% CI = 1.09-1.41, P < 0.001), low respiratory muscle strength (HR = 1.31, 95% CI = 1.11-1.54, P = 0.001), and probable RS (HR = 1.31, 95% CI = 1.15-1.48, P < 0.001) were associated with increased all-cause mortality. However, when the follow-up period was shortened to 2 years, the association between probable RS and all-cause mortality became non-significant (P = 0.246), although it remained significant for respiratory-related mortality (HR = 3.16, 95% CI = 1.39-7.18, P = 0.006). Diagnosing probable RS and leading to intervention could significantly prevent and reduce the burden of long-term all-cause mortality.