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

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.

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.

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 (χ ² = 6.13, P = 0.0133).

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.