Risk factors and outcomes of acute kidney injury among covid-19 patients at a tertiary hospital in Kenya

Background: Corona Virus Disease 2019 (COVID-19), a novel infection caused by the SARS-Cov-2 virus, was declared a global pandemic on March 11, 2020. Three years later, 350,000 Kenyans had gotten the infection, with approximately 5,700 reported related deaths. Despite emerging research on the new virus, studies from the African continent on the impact of COVID-19 on the kidneys have been few. Early studies suggest that up to 75% of patients with COVID-19 have a derangement in their kidney function as evidenced by new onset proteinuria and hematuria. That said, the prevalence of acute kidney injury has varied greatly across populations, ranging from nine to fifty-five percent depending on the geographical area, differences in COVID-19 infection severity, race, age, and the socioeconomic status of the patient population. Being of African descent in particular has been identified as an independent risk factor for AKI in many of these studies. Acute kidney injury in hospitalized patients is associated with increased mortality risk and a prolonged duration of hospital stay, with higher odds seen among patients with COVID-19 infection. In addition, AKI-recovered patients are less likely to have complete recovery of their renal function, even after clearance of the infection, and have been shown to have a faster progression in chronic kidney disease on follow-up. Objective: The study aims to determine the impact of COVID-19 infection on the kidneys. The primary objective is to determine the prevalence and risk factors of acute kidney injury in COVID-19 patients at a tertiary-level hospital in Nairobi, Kenya. The secondary objective is to assess the short-term outcomes of AKI in these patients at the time of hospital discharge. These outcomes include in-hospital mortality rate, the duration of hospital stay, and the status of renal recovery. Methods: In this retrospective cohort study, COVID-19 patients above the age of 18 years admitted between April 1st 2020 and October 31st 2021 were included. Patients without serial creatinine results and those with end-stage renal disease met the exclusion criteria. Data was collected on demographic and clinical characteristics. After determining the AKI period prevalence, bivariate analysis was carried out to determine statistically significant associations of these factors with AKI, with a p-value set at 0.05. A logistic regression model was then applied to determine independent associations with AKI, with results reported as an odds ratio with a 95% confidence interval, and adjusted for age and gender. The iv outcomes of AKI were stratified based on the stage of AKI and reported as percentages, medians, and interquartile ranges. Methods: In this retrospective cohort study, COVID-19 patients above the age of 18 years admitted between April 1st 2020 and October 31st 2021 were included. Patients without serial creatinine results and those with end-stage renal disease met the exclusion criteria. Data was collected on demographic and clinical characteristics. After determining the AKI period prevalence, bivariate analysis was carried out to determine statistically significant associations of these factors with AKI, with a p-value set at 0.05. A logistic regression model was then applied to determine independent associations with AKI, with results reported as an odds ratio with a 95% confidence interval, and adjusted for age and gender. The iv outcomes of AKI were stratified based on the stage of AKI and reported as percentages, medians and interquartile ranges. Conclusion: Acute kidney injury is a less recognized complication of COVID-19 infection. We found significantly higher odds of AKI with increasing age, gender, hypertension, diabetes and severity of COVID-19 illness. We also demonstrated a strong independent association between AKI in COVID-19 and mortality and an impact of AKI in COVID-19 on hospital duration and renal recovery