Global geographic and socioeconomic disparities in COVID-associated acute kidney injury: a systematic review and meta-analysis.

BACKGROUND

Acute kidney injury (AKI) is a common and severe complication of COVID-19, which significantly increases the risk of mortality. There has been a wide range of AKI prevalence reported throughout the pandemic, reflecting differences in geographic location, patient characteristics, and health care resources. We aimed to provide a global overview of the COVID-19 AKI prevalence reported in published studies to uncover geographic and socioeconomic disparities.

METHODS

We undertook a systematic review and meta-analysis, searching PubMed, Embase, Scopus, Web of Science, and Cochrane Library for full-text articles published in English reporting the prevalence of AKI from January 2020 to November 2023. All studies defined AKI according to the Kidney Disease Improving Global Outcomes criteria. Clinical characteristics were extracted and examined from 334 studies that met the inclusion criteria. With significant study heterogeneity, random-effect models were estimated. We reported pooled AKI prevalence by country, region, and income level. Meta-regression further examined the relationship between COVID-associated AKI and geographic location.

RESULTS

After removing studies that utilised the same data, 345 796 patients from 246 studies were included, covering 49 countries. Of 246 studies, 137 came from high-income countries, whereas only three were conducted in low-income countries. Among non-intensive care unit (ICU) patients, low-income countries had the lowest COVID-19 AKI prevalence (14.1%; 95% confidence interval (CI) = 11.4-17.2). Among ICU patients, lower-middle-income countries had the lowest COVID-19 AKI prevalence (27.9%;95% CI = 19.4-38.4).

CONCLUSIONS

Our study shows significant geographic and socioeconomic disparities in the prevalence of COVID-associated AKI, with a higher prevalence in high-income countries and a lower prevalence in low- and lower-middle-income countries. This study is the most comprehensive systematic review and meta-analysis highlighting global disparities in COVID-associated AKI prevalence. Further studies are needed to explain the reasons behind these differences.