Impact of Contrast-Associated Acute Kidney Injury on One-Year Outcomes in Very Elderly STEMI Patients: Insights From a Multicenter Registry in Northern Italy.

Data about contrast-associated acute kidney injury (CA-AKI) in oldest old (age ≥85 years) ST-elevation myocardial infarction (STEMI) patients are scarce. We evaluated the incidence and the 1-year prognostic impact of CA-AKI in this population. Patients were included in a multicenter real-world registry, and CA-AKI was defined according to KDIGO (Kidney Disease Improving Global Outcomes) criteria. Major adverse cardiac and cerebrovascular events (MACCEs) were defined as the composite of all-cause death, stroke, unplanned coronary revascularization, and heart failure hospitalization. The primary outcome was the incidence and impact of CA-AKI on MACCEs at 1 year follow-up. Out of 461 STEMI patients (mean age 88.6 ± 2.9 years), 102 (22.1%) patients developed CA-AKI. Chronic kidney disease was the strongest predictor of CA-AKI (odds ratio [OR]: 4.52, 95% CI: 2.81-7.30, P < .01). The CA-AKI cohort showed a higher risk of MACCEs (adjusted HR: 1.75, 95% CI: 1.13-2.71, P = .01), driven mainly by all-cause death (adjusted hazard ratio [HR]: 2.39, 95% CI: 1.41-4.07, P = .01) and followed by heart failure hospitalization (adjusted HR: 2.01, 95% CI: 1.08-3.76, P = .01). Among oldest old STEMI, CA-AKI was frequent and associated with a higher incidence of MACCEs at 1-year follow-up.