COVID-19 is known to cause respiratory failure. It is also associated with damage to other organs including the kidneys. Results of previous studies have suggested a significant association between acute kidney injury (AKI) associated with COVID-19 and mortality. According to David J. Wilhelm, DO, and colleagues at the University of Louisville, Kentucky, there are few data regarding varying effects of AKI on mortality across variants of the virus.
The researchers conducted a study to examine the association between AKI and in-hospital mortality among patients with COVID-19 pneumonia (PNA) during the original strain and the delta variant. Results were published in conjunction with the American Society of Nephrology Kidney Week 2022 in a report titled Predicting In-Hospital Mortality Among COVID-19 Pneumonia Patients with AKI.
The retrospective analysis utilized data on patients hospitalized with COVID-19 PNA from March 2020 through March 2021. The database included two cohorts: one cohort with the original COVID-19 strain and the other with the delta variant. AKI was confirmed for 612 patients using the Acute Kidney Injury Network criteria (creatinine ≥0.3 mg/dL above baseline). Chronic kidney disease (CKD) was defined by estimated glomerular filtration rate (eGFR) calculated using the CKD-Epidemiology Collaboration 2021 equation. The relative risk for mortality was estimated with logistic regression using the following factors: AKI vs non-AKI; COVID-19 cohort; age; sex; race; and eGFR.
Of the 612 patients, 67.6% (n=414) had AKI. Of the total cohort, 443 patients survived to hospital discharge. Among the patients who died, 84% had AKI, 64% were male, and 30% were African American. Nonsurvivors were younger and had a lower eGFR.
In summary, the authors said, “Analyses showed that among patients hospitalized with COVID-19 PNA, the relative risk of in-hospital mortality was 3.28 times higher for those with AKI compared with those without AKI. We found no significant difference for in-hospital mortality between the two cohorts when adjusted for presence of AKI. Other findings showed that males may have a greater risk of morality as compared to females and those of African American race may have a potential survival advantage.”
Source: Wilhelm DJ, Ali T, Brier ME, Caster DJ, Arnold FW, Huang J. Predicting in-hospital mortality among COVID-19 pneumonia patients with AKI. POB005. Abstract of a report published in conjunction with the American Society of Nephrology Kidney Week 2022.