A systematic review of the prevalence and diagnostic approaches of respiratory sarcopenia

Abstract Background Respiratory sarcopenia (RS) is a recently described condition characterized by the coexistence of sarcopenia and respiratory dysfunction. In addition to the physical consequences of sarcopenia, RS is accompanied by respiratory dysfunction, potentially increasing aging-related functional decline. However, its prevalence and diagnostic approaches remain unclear, and no global consensus has been established. This study systematically reviews the prevalence and diagnostic approaches of RS. Methods We conducted a systematic review following the Preferred Reporting Items for Systematic Reviews and Meta Analyses 2020 guidelines. Searches were performed in PubMed, Scopus, EMBASE, Lilacs, and SciELO in October 2025 using the term “respiratory sarcopenia” without filters. Quantitative synthesis included only cross-sectional, cohort, and longitudinal studies. Data on study characteristics, diagnostic methods, and prevalence were extracted, and risk of bias was assessed using the Joanna Briggs Institute critical appraisal tool. Results Here we show that 27 studies involving 31,210 predominantly older adults were included, revealing an estimated global RS prevalence of 18.7%. Estimated prevalence is 18.8% in older adults, 17.1% in non-older populations, and 75.8% in populations with secondary conditions. Studies using the JARN recommendations report higher prevalence than those using the criteria proposed by Kera et al. Substantial heterogeneity remains, particularly regarding assessment methods. Conclusions RS is a prevalent but inconsistently defined condition, and current evidence is limited by diagnostic heterogeneity. A global consensus may improve diagnostic standardization, comparability across studies, and future clinical applications.