Psoas muscle index as a predictor of mortality following percutaneous coronary intervention

Background  Percutaneous coronary intervention (PCI) is a widely utilized revascularization technique for coronary artery disease (CAD). While clinical and biomarker-based prognostic tools are standard for predicting outcomes, there is growing interest in sarcopenia as a marker of frailty and its potential role in long-term prognosis. The prognostic value of the psoas muscle index (PMI), a sarcopenia metric, remains underexplored in PCI populations regarding long term survival.

Methods  This single-center retrospective cohort study evaluated 177 patients undergoing PCI from 2015 to 2019. PMI was calculated from computed tomography (CT) imaging at the L3 vertebral level using the formula: (left psoas area + right psoas area)/height² and expressed in cm²/m². Sarcopenia was defined as the lowest sex-specific PMI quartile. Primary outcomes included 5-year all-cause mortality and 3-point major adverse cardiovascular events (MACE: non-fatal myocardial infarction, ischemic stroke, and cardiac death). Binary linear regression and Cox proportional hazards models were utilized to determine associations between PMI and outcomes

Results  Sarcopenic patients exhibited significantly higher 5-year all-cause mortality compared to non-sarcopenic counterparts (64.4% vs. 35.6%, P < 0.001), while no significant difference was observed in 3-point MACE incidence (55.6% vs. 51.4%, P = 0.520). Sarcopenia was independently associated with all-cause mortality on binary logistic regression (OR = 3.49; 95% CI: 1.69–7.19; P = 0.0007), but not MACE (OR = 1.00; 95% CI: 0.50–1.98; P = 0.99). In a multivariable Cox regression model, sarcopenia was associated with increased hazard of mortality (HR = 1.60; 95% CI: 0.96–2.66; P = 0.071), though this did not reach statistical significance. Kaplan-Meier analysis demonstrated significantly reduced survival among sarcopenic patients (χ² = 6.13, P = 0.0133).

Conclusions  PMI is a significant independent predictor of 5-year all-cause mortality in PCI patients, underscoring the prognostic importance of assessing skeletal muscle mass in this population.