A Cross-Sectional Study of the Prevalence and Outcomes of Acute Kidney Injury in Patients with Covid 19 at a Tertiary Hospital in Nairobi

ABSTRACT

Introduction: AKI has been shown to be more prevalent in COVID-19 patients across the disease spectrum compared to non-COVID patients. Black race is an independent risk factor for AKI in COVID-19 patients, with an AKI prevalence ranging from 1.3-2.5 times that of other races. Reasons for this difference include socioeconomic disadvantages, increased and uncontrolled use of nephrotoxic drugs and a higher prevalence of poorly controlled comorbid conditions in the Black population. The objective of our study was to determine the prevalence, risk factors and outcomes of AKI in patients hospitalized with COVID-19 in Kenya. Method(s) This retrospective cohort study included 1366 patients with confirmed COVID-19 illness hospitalized at a tertiary level teaching hospital in Kenya between April 1st, 2020 and October 31st, 2021. Data was collected on age, gender, the severity of COVID-19 illness, and comorbid conditions including HIV, diabetes, hypertension, CKD and post-renal transplant patients. Univariate analysis was carried out to determine the association of clinical and demographic factors with AKI. To determine independent associations with AKI incidence, a logistic regression model was used and the relationship was reported as odds ratios with a 95% confidence interval. The primary outcome of AKI in COVID-19 patients in this study is the in-hospital mortality rate. Other secondary outcomes assessed include the status of renal recovery at hospital discharge and the duration of hospital stay. Result(s) The median age of study patients was 56 years with 67% of them being male. The AKI prevalence in the study period was 21.6% (n=295).Patients with AKI were older more likely to be male. Comorbid conditions related to the development of AKI in COVID-19 patients in our setting include diabetes and hypertension, with an adjusted odds ratio of 1.75 (95% CI 1.34-2.30;p value <0.001) and 1.68 (95% CI 1.27-2.23;p value <0.001) respectively. Chronic kidney disease was also associated with AKI incidence, with an adjusted odds ratio of 2.70 (95% CI 1.86-3.93;p value <0.001). Patients with AKI had significantly higher odds of mortality when compared to those without AKI, and this effect was proportional to the stage of AKI. In this study, COVID-19 patients with AKI were 11 times more likely to die while hospitalized (95% CI 7.56-17.03;p value <0.001), with mortality seen in 65% of patients with stage 3 AKI as compared to 18% of patients with stage 1 AKI. In terms of renal recovery at hospital discharge, 95% of patients with stage 1 AKI had complete renal recovery vs 33% of patients with stage 3 AKI. Of the patients with stage 3 AKI (n=64), 10 underwent hemodialysis, with 1 recovery in renal function and 3 patients requiring ongoing dialysis after discharge. Lastly, patients with AKI had a longer hospital stay (10 days [IQR 5-18] vs 8 days [IQR 5-10];P<0.001). Conclusion(s) We found significantly higher odds of AKI with increasing age, gender, hypertension, diabetes, chronic kidney disease and severity of COVID-19 illness. We found no association between AKI and pregnancy or comorbid conditions like HIV and post-renal transplant. In this study, we demonstrated a strong independent association between AKI in COVID-19 and mortality. The study also showed the impact of AKI on hospital duration and the effect of COVID-19 disease on renal recovery in AKI patients. No conflict of interestCopyright © 2023