Physical performance and outcomes after myocardial infarction in older patients undergoing multidomain cardiac rehabilitation.

AIMS: To investigate the prognostic role of physical performance as a marker of vulnerability in older patients after myocardial infarction and its interaction with a multidomain cardiac rehabilitation intervention. METHODS AND RESULTS: In this prespecified subanalysis of the PIpELINe trial, physical performance was evaluated using the Short Physical Performance Battery (SPPB). Patients aged ≥65 years with intermediate SPPB scores (4-9) were randomized in a 2:1 ratio to a multidomain rehabilitation programme or usual care. The primary outcome was a composite of cardiovascular death or unplanned hospitalization for cardiovascular causes at 1 year. Associations between baseline SPPB, its individual components, longitudinal changes over time, and clinical outcomes were examined using competing-risk models. Among 512 randomized patients, lower baseline SPPB scores were associated with a significantly higher risk of the primary outcome (HR 0.51, 95% CI 0.32-0.82). No interaction was observed between baseline SPPB and treatment assignment, indicating a consistent benefit of intervention across levels of physical performance. Among individual SPPB components, gait speed emerged as the strongest prognostic marker, with an approximately 50% reduction in risk per 1-point increase (HR 0.50, 95% CI 0.37-0.68; P < 0.001). Improvement in SPPB of at least one point during follow-up was associated with a lower risk of adverse outcomes. CONCLUSION: In older myocardial infarction patients, baseline physical performance is a strong and independent predictor of adverse cardiovascular outcomes without modifying the benefit of multidomain cardiac rehabilitation. Gait speed represents a simple and pragmatic marker of risk, and functional improvement over time is associated with better prognosis. REGISTRATION: ClinicalTrials.gov NCT03021044.