Differences in Circulating Inflammatory Markers in Older Adults With and Without Sarcopenia: A Systematic Review and Meta-Analysis

Objectives In this systematic review and meta-analysis, mean differences among high-sensitivity C-reactive protein (CRP), CRP, interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-α), the most common markers used in clinical practice, between older adults with and without sarcopenia based on established consensus were explored. Design A random-effects model meta-analysis was used to estimate the pooled effects of the included studies (CRD42024503466). Heterogeneity was assessed via meta-regressions, whereas publication bias was evaluated through Egger's test and funnel plots. Setting and Participants Forty-four studies with cross-sectional baseline data were included in this study. Methods Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020 guidelines, a systematic literature search of studies was conducted using PubMed, Cochrane Library, Web of Science, and Scopus. Results Sarcopenia exhibited a significant higher inflammatory profile compared with those without sarcopenia (CRP: standardized mean difference [SMD], 0.27; 95% CI, 0.14-0.40; I 2 = 82%; P < .01), (high-sensitivity CRP: SMD, 0.40; 95% CI, 0.20-0.60; I 2 = 79%; P < .01), (IL-6: SMD, 0.34; 95% CI, 0.12-0.56; I 2 = 72%; P < .01), (tumor necrosis factor-alpha: SMD, 0.78; 95% CI, 0.25-1.32; I 2 = 92%; P < .01). Overall, the quality of the studies was considered low. Publication bias was found in relation to IL-6, for which, following trim of 6 studies, an insignificant effect between groups was observed (SMD, 0.12; 95% CI, −0.38 to 0.61). Conclusions and Implications This meta-analysis showed a higher level of inflammation in sarcopenia vs nonsarcopenia. Longitudinal studies controlling for reported comorbidities and infections are needed to establish causality.