Incidence of acute kidney injury and its association with mortality in patients with COVID-19: a meta-analysis

Acute kidney injury (AKI) is a complication of COVID-19. However, the incidence of AKI in COVID-19 varies among studies. Thus, we aimed to evaluate the pooled incidence of AKI and its association with mortality in patients with COVID-19 using a meta-analysis. We search Ovid MEDLINE, EMBASE, and the Cochrane Library for eligible publications reporting the clinical characteristics of patients with COVID-19 without language restriction. Incidence of AKI and mortality were reported. Meta-regression was used to describe the association between outcomes. From 26 studies (n=5497), the pooled incidence of AKI in patients with COVID-19 was 8.4% (95% CI 6.0% to 11.7%) with a pooled incidence of renal replacement therapy of 3.6% (95% CI 1.8% to 7.1%). The incidence of AKI was higher in critically ill patients (19.9%) compared with hospitalized patients (7.3%). The pooled estimated odds ratio for mortality from AKI was 13.33 (95% CI 4.05 to 43.91). No potential publication bias was detected. By using meta-regression analyses, the incidence of AKI was positively associated with mortality after adjusted for age and sex (Q=26.18; p=0.02). Moreover, age (p