Sex Differences in Acute Kidney Injury After Venoarterial Extracorporeal Membrane Oxygenation for Cardiogenic Shock

Background: Sex-based differences in complications after venoarterial extracorporeal membrane oxygenation (VA-ECMO) for cardiogenic shock are not well defined. We compared 30-day coded acute kidney injury and other short-term outcomes between female and male patients receiving ECMO. Methods: We performed a retrospective multicenter cohort study using the TriNetX U.S. Collaborative Network from 2012 through 2025. Adults with cardiogenic shock supported with VA-ECMO were identified. Patients with a diagnosis-coded AKI (ICD-10-CM N17) recorded on or before the index ECMO procedure were excluded, and female and male cohorts were then matched 1:1 by propensity score on 23 characteristics. The primary endpoint was diagnosis-coded AKI between day 1 and day 30 after ECMO initiation. Secondary endpoints were all-cause mortality, newly diagnosis-coded sepsis, and newly diagnosis-coded ischemic stroke. Results: Among 11,229 adults meeting cohort criteria, 3773 were women, and 7456 were men. After exclusion of 8272 patients with previously coded AKI, 1152 women and 1805 men were eligible, and 1100 patients were matched in each group. Diagnosis-coded AKI occurred in 222 women (20.2%) and 276 men (25.1%) (risk ratio, 0.80; 95% confidence interval [CI], 0.69–0.94; hazard ratio [HR], 0.78; 95% CI, 0.65–0.93; p = 0.005). All-cause mortality was identical between groups (29.5% vs. 29.5%; risk ratio, 1.00; 95% CI, 0.88–1.14). Newly coded sepsis (5.1% vs. 6.3%) and newly coded ischemic stroke (4.0% vs. 3.2%) did not differ significantly. In an unadjusted Aalen–Johansen analysis performed in the unmatched eligible cohorts, the 30-day cumulative incidence of coded AKI was 21.6% among women and 27.8% among men. Conclusions: In this propensity-matched federated electronic health record cohort of adults with cardiogenic shock receiving VA-ECMO and without previously coded AKI, recorded female sex was associated with a lower 30-day risk of diagnosis-coded AKI. Mortality, newly coded sepsis, and newly coded ischemic stroke were similar. These findings are hypothesis-generating and support further investigation of sex-associated differences in datasets with granular renal and ECMO-specific variables.