RESUMEN
BACKGROUND: Myocardial infarction (MI) patients are increasingly older, and common risk scores include chronological age, but do not consider chronic comorbidity or biological age. Frailty status reflects these variables and may be independently correlated with prognosis in this setting. OBJECTIVE: This study investigated the impact of frailty on the prognosis of elderly patients admitted due to MI. METHODS: This prospective and observational study included patients ≥75 years admitted to three tertiary hospitals in Spain due to MI. Frailty assessment was performed at admission using the Survey of Health, Ageing and Retirement in Europe Frailty Index (SHARE-FI) tool. The primary endpoint was the composite of death or non-fatal reinfarction during a follow-up of 1 year. Overall mortality, reinfarction, the composite of death, reinfarction and stroke, major bleeding, and readmission rates were also explored. RESULTS: A total of 285 patients were enrolled. Frail patients (109, 38.2%) were older, with a higher score in the Charlson Comorbidity Index and with a higher risk score addressed in the GRACE and CRUSADE indexes. On multivariate analysis including GRACE, CRUSADE, maximum creatinine level, culprit lesion revascularization, complete revascularization, and dual antiplatelet therapy at discharge, frailty was an independent predictor of the composite of death and reinfarction (2.81, 95% CI 1.16-6.78) and overall mortality (3.07, 95% CI 1.35-6.98). CONCLUSION: Frailty is an independent prognostic marker of the composite of mortality and reinfarction and of overall mortality in patients aged ≥75 years admitted due to MI.