Decreasing Incidence of AKI in Patients with COVID-19 critical illness in New York City

Charytan, David M.; Parnia, Sam; Khatri, Minesh; Petrilli, Christopher M.; Jones, Simon; Benstein, Judith; Horwitz, Leora I.

INTRODUCTION: Reports from the United States suggest that acute kidney injury (AKI) frequently complicates COVID-19, but understanding of AKI risks and outcomes is incomplete. Additionally, whether kidney outcomes have evolved during the course of the pandemic is unknown. METHODS: We used electronic records to identify COVID-19 patients with and without AKI admitted to 3 New York Hospitals between March 2 and August 25, 2020. Outcomes included AKI overall and according to admission week, AKI stage, the requirement for new renal replacement therapy (RRT), mortality and recovery of kidney function. Logistic regression was utilized to assess associations of patient characteristics and outcomes. RESULTS: Out of 4732 admissions 1386 (29.3%) patients had AKI. Among those with AKI, 717 (51.7%) had Stage 1, 132 (9.5%) Stage 2, 537 (38.7%) stage 3, and 237 (17.1%) required RRT initiation. In March 536/1648 (32.5%) of patients developed AKI compared with 15/87 (17.2%) in August (P<0.001 for monthly trend) whereas RRT initiation was required in 6.9% and 0% of admission, in March and August respectively. Mortality was higher with than without AKI (51.6% vs 8.6%) and was 71.9% in individuals requiring RRT. However, most patients with AKI who survived hospitalization (77%) recovered to within 0.3 mg/dL of baseline creatinine. Among those surviving to discharge, 62% discontinued RRT. CONCLUSIONS: AKI impacts a high proportion of admitted COVID-19 patients and is associated with high mortality, particularly when RRT is required. AKI incidence appears to be decreasing over time and kidney function frequently recovers in those who survive.