Prognostic Impact of Sarcopenia Following Myocardial Infarction: A Systematic Review and Meta-analysis of Mortality and Recurrent MI

Abstract Aim Sarcopenia, defined as progressive loss of skeletal muscle mass and function, may influence cardiovascular outcomes, yet its prognostic role after myocardial infarction (MI) remains uncertain. This study aimed to assess the association between sarcopenia and outcomes following MI, focusing on all-cause mortality and recurrent MI. Methods and Results We registered a protocol (PROSPERO CRD420251048284) and searched PubMed, Embase, Web of Science, Scopus, and the Cochrane Library to January 2025. Eligible observational cohorts assessed sarcopenia at or shortly after an index MI using validated definitions (CT, DXA, or laboratory proxies). The primary outcome was all-cause mortality; recurrent MI was secondary. Four post-MI cohorts (n = 939) showed higher mortality in patients with sarcopenia (pooled OR, 2.84; 95% CI, 1.85–4.36; I2 = 0%). Effects were consistent at ≤12 months (OR, 2.55; 95% CI, 1.42–4.58) and >12 months (OR, 3.21; 95% CI, 1.72–6.02). Only two cohorts reported recurrent MI: the pooled estimate suggested a possible increased risk but was highly imprecise and heterogeneous (OR, 2.21; 95% CI, 0.22–22.06; I2 = 81%), precluding definitive conclusions. Three PCI all-comer cohorts, analyzed as sensitivity only, also indicated higher mortality. Certainty of evidence was moderate for mortality and very low for recurrent MI. Conclusions Sarcopenia assessed around the time of MI is consistently associated with a threefold increase in all-cause mortality, with robust effects across short- and long-term follow-up. Evidence for recurrent MI remains exploratory. Routine muscle assessment may enhance post-MI risk stratification, and multicentre cohorts with standardized definitions are needed to determine whether targeting sarcopenia can improve outcomes.