The Prevalence of Acute Kidney Injury in Patients Hospitalized With COVID-19 Infection: A Systematic Review and Meta-analysis

Kidney Med. Jan-Feb 2021;3(1):83-98.e1. doi: 10.1016/j.xkme.2020.11.008. Epub 2020 Dec 9.


Rationale & objective: Coronavirus disease 2019 (COVID-19) may be associated with high rates of acute kidney injury (AKI) and kidney replacement therapy (KRT), potentially overwhelming health care resources. Our objective was to determine the pooled prevalence of AKI and KRT among hospitalized patients with COVID-19.

Study design: Systematic review and meta-analysis.

Data sources: MEDLINE, Embase, the Cochrane Library, and a registry of preprinted studies, published up to October 14, 2020.

Study selection: Eligible studies reported the prevalence of AKI in hospitalized patients with COVID-19 according to the Kidney Disease: Improving Global Outcomes (KDIGO) definition.

Data extraction & synthesis: We extracted data on patient characteristics, the proportion of patients developing AKI and commencing KRT, important clinical outcomes (discharge from hospital, ongoing hospitalization, and death), and risk of bias.

Outcomes & measures: We calculated the pooled prevalence of AKI and receipt of KRT along with 95% CIs using a random-effects model. We performed subgroup analysis based on admission to an intensive care unit (ICU).

Results: Of 2,711 records reviewed, we included 53 published and 1 preprint study in the analysis, which comprised 30,657 hospitalized patients with COVID-19. Data for AKI were available for 30,639 patients (n = 54 studies), and receipt of KRT, for 27,525 patients (n = 48 studies). The pooled prevalence of AKI was 28% (95% CI, 22%-34%; I 2 = 99%), and the pooled prevalence of KRT was 9% (95% CI, 7%-11%; I 2 = 97%). The pooled prevalence of AKI among patients admitted to the ICU was 46% (95% CI, 35%-57%; I 2 = 99%), and 19% of all ICU patients with COVID-19 (95% CI, 15%-22%; I 2 = 88%) commenced KRT.

Limitations: There was significant heterogeneity among the included studies, which remained unaccounted for in subgroup analysis.

Conclusions: AKI complicated the course of nearly 1 in 3 patients hospitalized with COVID-19. The risk for AKI was higher in critically ill patients, with a substantial number receiving KRT at rates higher than the general ICU population. Because COVID-19 will be a public health threat for the foreseeable future, these estimates should help guide KRT resource planning.

Keywords: Acute kidney injury; COVID-19; Kidney Replacement therapy; Meta-analysis; SARS-CoV2.