Factors associated with acute kidney injury (AKI) and mortality in COVID-19 patients in a Sub-Saharan African intensive care unit: a single-center prospective study

Abstract

Introduction Acute kidney injury (AKI) is a complication of severe coronavirus disease 2019 (COVID-19). Kidney damage associated with COVID-19 could take specific features due to environmental and socio-cultural factors. This study evaluates the incidence of AKI, the associated factors, and mortality in COVID-19 patients in a Sub-Saharan African intensive care unit. Methods In a prospective cohort study conducted in the intensive care unit (ICU) of the Centre Médical de Kinshasa (CMK), consecutive patients admitted for COVID-19 were screened for the presence of AKI between 27 March, 2020 and 27 January 2022. AKI was defined according to Kidney Disease Improving Global Outcomes (KDIGO) guidelines. The primary outcome was occurrence of AKI. The secondary outcome was 48 days’ mortality and recovery of the renal function at intensive care unit (ICU) discharge. Survival (time-to death) curves were built using the Kaplan Meier methods. Multivariate analyses were performed by logistic regression to identify factors associated with AKI and Cox regression to explore the association between AKI and in-hospital mortality. The significance level of the p -value was set at 0.05. Results The median(IQR) sequential organ failure assessment score (SOFA) score and mean age of patients (215) including in our cohort were respectively 3(2-4) and 58.9 ± 14.9 years. The incidence of AKI was 28.4% with stages 1, 2, or 3 AKI accounted for 39.3%, 11.5%, and 49.2%, respectively. Hemodialysis was required in 16 out 215 (7.4%) patients. Dyspnea (adjusted odds ratio (aOR):2.27 [1.1–-4.57] p = 0.021), SOFA ≥5 (aOR:3.11[1.29–7.53] p = 0.012), AST/ALT ratio (aOR: 1.53 [1.09–1.79] p = 0.015), N/L ratio (aOR:2.09 [1.09–3.20] p = 0.016), mechanical ventilation (aOR: 3.20 [1.66–10.51] p = 0.005) and Amikacin (aOR: 2.91 [1.37–6.18] p = 0.006) were the main factors associated with AKI. Patients with AKI had a mortality rate of 52.5% and 67.2% of the survivors did not recover kidney function at the end of hospitalization. Adjusted Cox regression analysis revealed that COVID-19-associated AKI was independently associated with in-hospital death (HR:2.96 [1.93–4.65] p = 0.013) compared to non-AKI patients. Conclusions AKI was present in three out of ten COVID-19 patients. The most significant factors associated with AKI were dyspnea, SOFA ≥ 5, AST/ALT and N/L ratio, mechanical ventilation and Amikacin. AKI has been associated with an almost threefold increase in overall mortality and seven out of ten survivors did not recover kidney function after AKI.

Kidney damage associated with COVID-19: from the acute to the chronic phase

“…Various meta-analyses on AKI associated with COVID-19 (COV-AKI) reports a frequency between 10 and 17%, with a wide range between 0.5% and 80.5% [ 11–14 ]. This discrepancy, which has also been noted in recent African and Latin American studies, is due to several factors, including the lack of agreement between the definitions used [ 2 , 15–18 ]. Indeed, the definition and/or detection of AKI is mainly based on acute changes in serum creatinine and therefore the frequency of creatinine tests has an impact on the detection rate of AKI.…”

“…After adjusting for the frequency of serum creatinine testing, the incidence of AKI increased to 11.6% [ 4 ]. The characteristics of the study population in relation to the severity of the disease (the virulence of the SARS-COV-2 variant associated with the COVID-19 wave, the burden of comorbidities [age, chronic kidney disease, heart failure, diabetes mellitus, arterial hypertension, obesity], the genetic predisposition [APOL-1 polymorphism], admission to intensive care unit or not, use of mechanical ventilation with prone position or not and the income level of the country) could account for the wide variability of the frequencies of COV-AKI reported in the literature [ 2 , 8 , 19–21 ]. In a retrospective multicenter study in the USA, Chan Li et al.…”

“…The incidence and severity of AKI (AKI requiring dialysis) decreased over time and across COVID-19 waves, with the first wave being more severe [ 2 , 26 , 27 ]. These results could indicate, on the one hand, a reduction in the virulence of SARS-CoV-2 due to multiple mutations and, on the other hand, the impact of vaccination in creating collective immunity beyond natural infection and the improvement in the management of COVID-19 with the introduction of corticosteroids in the treatment of severe cases of COVID-19 [ 28 , 29 ].…”

“…Its presence in renal cells, particularly tubular, glomerular and endothelial cells, justifies the various functional and histological disorders associated with COVID-19 [ 1 ]. Since the onset of the COVID-19 pandemic, a wide range of renal manifestations has been reported including proteinuria, hematuria and acute kidney injury (AKI) [ 2 , 3 ]. Renal histological studies have identified acute tubular injury and collapsing glomerulopathy as the main lesions associated with COVID-19 [ 2 , 4 , 5 ].…”

“…Since the onset of the COVID-19 pandemic, a wide range of renal manifestations has been reported including proteinuria, hematuria and acute kidney injury (AKI) [ 2 , 3 ]. Renal histological studies have identified acute tubular injury and collapsing glomerulopathy as the main lesions associated with COVID-19 [ 2 , 4 , 5 ]. Although COVID-19 mortality has decreased significantly in the world overtime, the challenge now is to address the long-term complications associated with COVID-19 in general and kidney damage in particular, especially as AKI is well established as a transitional phase leading to the onset or progression of chronic kidney disease (CKD) [ 6 ].…”