Frailty Among Patients With Acute ST-Elevation Myocardial Infarction in the United States: The Impact of the Primary Percutaneous Coronary Intervention on In-Hospital Outcomes.

OBJECTIVES: To determine the average treatment effect (ATE) of primary percutaneous coronary intervention (pPCI) versus medical treatment (MT) on in-hospital outcomes across the spectrum of frailty in patients with ST-elevation myocardial infarction (STEMI). METHODS: Adult patients hospitalized for STEMI between October 2015 until December 2017 from the National Inpatient Sample (NIS) database were retrospectively analyzed and stratified by the Hospital Frailty Risk Score into low, intermediate, and high frailty risk subgroups. Propensity score matching analysis was performed to estimate the ATE of pPCI in each frailty subgroup. The primary outcome was all-cause in-hospital death. RESULTS: A total of 429,070 patients were included in the final analysis, with 28.4% at an increased frailty risk. Frail patients were significantly less likely to receive pPCI (85.6%, 47.2%, and 22.6% for low, intermediate, and high frailty risk groups). Rates of adverse in-hospital events including death, cerebrovascular event, and major bleeding were significantly higher in patients with increased frailty risk. pPCI was associated with a significant reduction of in-hospital death in low (-8.0%), intermediate (-14.6%), and high (-14.7%) frailty subgroups, compared to MT (P<.001). CONCLUSIONS: pPCI was associated with reduced rates of in-hospital death in patients with frailty presenting with STEMI. These findings suggest a benefit of pPCI in this complex patient population, although based on observational data. Long-term effects and safety need to be investigated in future studies.