Early renal impairment is associated with in-hospital death of patients with COVID-19

Introduction Renal impairment is a common complication in coronavirus disease 2019 (COVID-19), although its prognostic significance remains unknown. Objectives This study determines the impact of early renal impairment on the clinical outcome of COVID-19. Methods Patients diagnosed with COVID-19 and hospitalized in Xiaogan Central Hospital from 20 January to 29 February 2020 were retrospectively included and grouped into two cohorts (cohort with normal renal function and cohort with renal insufficiency) based on the renal function detected on admission. Records of clinical manifestation, laboratory findings and clinical outcome were collected and compared between these two cohorts. Results A total 543 COVID-19 patients were included. Among these patients, 70 patients developed early renal impairment, with an incidence of 12.89%. A significantly higher white blood cell (WBC) count, C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), serum creatine (Cr), blood urine nitrogen (BUN) and brain natriuretic peptide (BNP) and a significantly lower blood platelet (PLT), lymphocyte count, prealbumin and albumin (ALB) were detected in the cohort with renal insufficiency (P < 0.05). Patients with early renal impairment were also associated with higher incidences of haematuria/proteinuria, higher incidences of mortality and prolonged hospitalization duration. The independent risk factors for in-hospital death included age >65 years old, complication of diabetes, renal impairment on admission (Cr > 73 mu mol/L and eGFR < 60 ml/min 1.73 m(2)), WBC > 9.5 x 10(9)/L and ALB < 35 g/L. Conclusion Early renal impairment is associated with higher risk of in-hospital death for patients with COVID-19. Risk stratification according to renal function can better guide the clinical management of COVID-19.