In-hospital outcomes of acute myocardial infarction and in-stent restenosis among end-stage renal disease patients: Insight from National Inpatient Sample

The incidence of in-stent restenosis (ISR) remains significant at 5–10 %, despite the widespread use of drug-eluting stents. Patients with ISR frequently present with acute coronary syndrome. End-stage renal disease (ESRD) is associated with accelerated atherosclerosis, and prior studies have demonstrated worse outcomes and higher mortality rates among ESRD patients undergoing percutaneous coronary intervention (PCI) compared to those without renal insufficiency. However, contemporary data regarding outcomes of acute myocardial infarction (AMI) in the setting of ISR in ESRD patients are limited. To this end, we sought to evaluate in-hospital outcomes of AMI and ISR for ESRD patients in the United States. Using the National Inpatient Sample between 2016 and 2020, we identified patients with discharge diagnoses of AMI associated with an ISR based on International Classification of Diseases, Tenth Revision (ICD-10) discharge diagnosis codes. Patients were stratified into two groups by ESRD status. The primary outcome was a comparison of in-hospital mortality between both groups and temporal trends in mortality over time. The study population included 142,455 patients hospitalized with AMI and ISR, of whom 11,905 (8.4 %) had an ESRD diagnosis. ESRD patients were more likely to present with a NSTEMI (90.6 % vs 77.3 %, p < 0.001). In-hospital mortality was higher among the ESRD group versus non-ESRD patients (7.9 % vs 3.0 %, P < 0.001). Mortality among ESRD patients increased by 3.8 % from 2016 to 2020 ( p = 0.01), whereas mortality remained stable among non-ESRD ( p = 0.10). On multivariate analysis, independent predictors of in-hospital mortality among the study cohort included ESRD (OR, 2.3; 95 % CI, 2.2–2.6; P < 0.001), advancing age, heart failure, STEMI, and cardiogenic shock. In conclusion, ESRD is an independent predictor of in-hospital mortality among patients hospitalized with AMI and ISR. These findings highlight the need for strategies to improve outcomes in this high-risk population.