Predictors of In-Hospital Mortality and 90-Day Kidney Outcomes in Hospitalized Adults with Sickle Cell Disease and AKI: A Multicenter Retrospective Study

Background: Sickle cell disease (SCD) is associated with a high burden of acute kidney injury (AKI) which is linked to long-term renal decline, including progression to chronic kidney disease (CKD). However, data remain limited on clinical predictors of in-hospital mortality and renal progression. We aimed to identify factors associated with these outcomes in hospitalized adults with SCD and AKI. Methods: This multicenter retrospective study involved adult SCD patients with AKI. (both community or hospital-acquired). The primary outcome was in-hospital mortality; the secondary outcome is development of CKD at 90-day follow-up among survivors. Descriptive statistics were used to compare clinical characteristics. Multivariate logistic regression was performed to identify independent predictors of mortality and CKD, reported as adjusted odds ratios (aORs) with 95% confidence intervals (CIs). Results: We identified 68 hospitalized adults with SCD and AKI. The mean age was 52.8 ± 16.1 years. Community-acquired AKI was more prevalent (85.2%, n=58). Overall, in-hospital mortality was 8.8% (n=6). Hospital-acquired AKI was associated with significantly higher mortality (30% vs.5.4%, p < 0.001). Multivariate analysis showed acute chest syndrome (ACS) (aOR 5.2, 95% CI 1.3–22.1), with history of coronary artery disease (aOR 6.7, 95% CI 1.4–31.2), ischemic stroke (aOR 4.5, 95% CI 1.1–19.4), ICU admission (aOR 7.8, 95% CI 2.1–28.3), and mechanical ventilation (aOR 9.4, 95% CI 2.3–38.2) were associated with in-hospital mortality. Among the 62 survivors, 25.8% (n=16) developed CKD at 90 days. Predictors of CKD included white race (aOR 4.3, 95% CI 1.2–15.8), history of ischemic stroke (aOR 3.9, 95% CI 1.1–13.6), and presence of sickle cell retinopathy (aOR 5.1, 95% CI 1.4–17.9). Conclusion: This multicenter study identifies key predictors of mortality and CKD progression in adults with SCD hospitalized for AKI. At 90-day follow-up, one in four survivors progressed to CKD. Prior ischemic stroke, and sickle cell retinopathy independently predicted CKD development, suggesting that micro and macrovascular complications may signal furure renal risk. These findings underscore importance of early identification and targeted interventions to improve long-term outcomes.