Outcomes Among Hospitalized Patients With COVID-19 and Acute Kidney Injury Requiring Renal Replacement Therapy

Abstract

IntroductionAcute kidney injury (AKI) occurs in up to 10%-30% of coronavirus disease 2019 (COVID-19) patients. AKI patients who require renal replacement therapy (RRT) often have concurrent respiratory failure and represent a high-mortality-risk population. The authors sought to describe outcomes in hospitalized COVID-19 patients with AKI requiring RRT and determine factors associated with poor outcomes. MethodsA retrospective cohort study of hospitalized COVID-19 patients with AKI requiring RRT during the period from March 14, 2020, to September 30, 2020, was performed at Kaiser Permanente Southern California. RRT was defined as conventional hemodialysis and/or continuous renal replacement therapy. The primary outcome was hospitalization mortality, and secondary outcomes were mechanical ventilation, vasopressor support, and dialysis dependence among discharged patients. Hospitalization mortality risk ratios were estimated up to 30 days from RRT initiation. ResultsA total of 167 hospitalized COVID-19 patients were identified with AKI requiring RRT. The study population had a mean age of 60.7 years and included 71.3% male patients and 60.5% Hispanic patients. Overall, 114 (68.3%) patients died during their hospitalization. Among patients with baseline estimated glomerular filtration rate (eGFR) values of ≥ 60, 30-59, and < 30 mL/min, the mortality rates were 76.8%, 78.1%, and 50.0%, respectively. Among the 53 patients who survived to hospital discharge, 29 (54.7%) continued to require RRT. Compared to patients with eGFR < 30 mL/min, the adjusted 30-day hospitalization mortality risk ratios (95% CI) were 1.38 (0.90-2.12) and 1.54 (1.06-2.25) for eGFR values of 30-59 and ≥ 60, respectively. ConclusionAmong a diverse cohort of hospitalized COVID-19 patients with AKI requiring RRT, survival to discharge was low. Greater mortality was observed among patients with higher baseline kidney function. Most of the patients discharged alive continued to be dialysis-dependent.

Keywords: COVID-19; acute kidney injury; dialysis/renal replacement therapy; mortality.

Figure 1:

A total of 167 patients (age ≥ 18 years) hospitalized with COVID-19 who developed acute kidney injury (AKI) requiring renal replacement therapy (RRT) were identified during the period from March 14, 2020, through September 30, 2020. ESKD = end-stage kidney disease; RT-PCR = reverse transcription-polymerase chain reaction.

Figure 2:

Among COVID-19 patients who developed acute kidney injury requiring renal replacement therapy for whom baseline estimated glomerular filtration rate (eGFR) information was available, hospitalization mortality rates were 76.8%, 78.1%, and 50% for patients with baseline eGFR values of ≥ 60, 30–59, and < 30 mL/min/1.73 m², respectively.