Incidence of, and Risk Factors and Outcomes Associated with, Acute Kidney Injury in COVID-19 at the National Kidney and Transplant Institute, Philippines

(1) Background: Acute kidney injury (AKI) in COVID-19 leads to an increase in patient mortality, especially among chronic kidney disease (CKD) patients. (2) Methods: A retrospective cohort of 519 adults admitted from 1 March 2020 to 1 March 2022 were reviewed for baseline characteristics and their association with renal outcomes. Patients were divided into diagnosed CKD, undiagnosed CKD, and normal eGFR. Chronic dialysis and kidney-transplant patients were excluded. Kaplan–Meier survival analysis at 7, 14, and 30 days from admission was performed. (3) Results: The overall incidence of AKI was 45.66%; the proportions among patients with diagnosed CKD, undiagnosed CKD, and normal eGFR were 76.64%, 38.75%, and 7.59%, respectively (p < 0.0001). Multivariate analysis showed that being male and inotrope use were significant risk factors for AKI, while higher eGFR was protective. AKI was associated with dialysis, invasive ventilation (p < 0.0001), prolonged hospitalization (p = 0.0001), and mortality (p < 0.0001). Renal recovery was 64%, 59%, and 23% in stages 1, 2, and 3 AKI, respectively, until 14 days from discharge (p < 0.0001). Patient survival was lower in cases of AKI: 83.16%, 70.59%, and 47.5% compared to non-AKI figures of 91.27%, 87.82%, and 76.95% at 7, 14, and 30 days respectively(p = 0.0001). (4) Conclusion: There was a higher incidence of AKI with worsening renal function. Intensified preventive measures for AKI are crucial to prevent its devastating consequences.