Acute kidney injury (AKI) is common among patients hospitalized with COVID-19, and it is associated with high mortality, according to recent reports.
In a study of 3993 patients aged 18 years or older hospitalized with COVID-19 in the Mount Sinai Health System in New York from February 27 to May 30, 2020, AKI occurred in 1835 patients (46%), co-first authors Lili Chan, MD, and Kumardeep Chaudhary, PhD, of the Icahn School of Medicine at Mount Sinai in New York, and colleagues reported in the Journal of the American Society of Nephrology. Of the patients with AKI, 347 (19%) required dialysis. The proportions of patients with stage 1, 2, and 3 AKI were 39%, 19%, and 42%, respectively.
Of the 3993 patients, 976 (24%) were admitted to an intensive care unit (ICU), 745 (76%) with AKI. Among ICU patients with AKI, the proportions with stage 1, 2, and 3 AKI were 28%, 17%, and 56%, respectively.
The overall in-hospital mortality rate was 50% among patients with AKI compared with 8% among those without AKI; among patients admitted to an ICU, the rates were 41% and 11%, respectively.
After adjusting for comorbidities, demographics, and laboratory values, the presence of AKI, compared with its absence, was significantly associated with 9.2-fold increased odds of in-hospital mortality for the overall cohort and 11.4-fold increased odds among patients admitted to an ICU.
Of the 1835 patients with AKI, 832 were discharged from the hospital. At hospital discharge, 541 of 832 (65%) had recovery of AKI to baseline kidney function, whereas 291 (35%) had acute kidney disease (AKD), according to the investigators. In addition, 36% of patients who did not have recovery of AKI at discharge did so on post-hospitalization follow-up, and 14% of those who had recovery of AKI at discharge had AKD on follow-up, according to the investigators.
“The study is the first in the United States to report the persistence of kidney dysfunction (lack of recovery) in survivors of COVID-19-associated AKI,” the investigators wrote. “A third of patients with AKI in the setting of COVID-19 did not recover kidney function back to baseline.”
Independent predictors of stage 3 AKI included male sex, admission potassium levels, and chronic kidney disease. In adjusted analyses, the presence of these characteristics, compared with their absence, was significantly associated with 1.46-, 1.70-, and 2.80-fold increased odds of incident AKI.
“The results of this study may be useful to other centers for resource planning during the COVID-19 pandemic, for potential additional waves of COVID-19, and for preparing for the increased load of patients with COVID-19 and CKD due to severe AKI and lack of recovery,” the author concluded.
In a separate study conducted in Europe, investigators found that severe AKI occurs frequently among patients with COVID-19 who have acute respiratory distress syndrome (ARDS), and it is associated with high short-term mortality.
Stéphane Gaudry, MD, PhD, of Avicenne Hospital in Bobigny, France, and colleagues studied 302 patients infected with SARS-CoV-2, the novel coronavirus that causes COVID-19, admitted to an ICU at 4 university hospitals. Of these, 82 did not receive invasive mechanical ventilation, 6 had end-stage kidney disease prior to infection, and 3 had cardiac arrest before hospital admission. The remaining 211 patients met the Berlin definition of ARDS and received invasive mechanical ventilation. Stage 3 AKI, based on Kidney Disease: Improving Global Outcomes (KDIGO) criteria, developed in 55 (26%) of these patients within 7 days after ICU admission, Dr Gaudry and colleagues reported in the American Journal of Respiratory and Critical Care Medicine. The median time from ICU admission to development of stage 3 AKI was 3 days.
In the remaining 156 patients, KDIGO AKI stages 1 and 2 developed in 26 (17%) and 25 (15%) patients, respectively, within 7 days following ICU admission.
Among the 55 patients with stage 3 AKI at 28 days after ICU admission, 31 (56%) died, 12 (22%) were still hospitalized in the ICU, and 12 (22%) were discharged alive from the ICU, Dr Gaudry’s team reported. For patients without stage 3 AKI, these figures were 38 (24%), 38 (24%), and 80 (51%), respectively.
On multivariable analysis, stage 3 AKI was significantly associated with 3.5-fold increased odds of mortality at 28 days.
Patients with stage 3 AKI were more likely to have chronic kidney disease, higher body mass index, and higher Sequential Organ Failure Assessment score, according to Dr Gaudry’s team. They also received higher positive end expiratory pressure and more frequently received nitric oxide therapy for vasopressor support. Thirty patients (54%) with AKI stage 3 within 7 days following ICU admission required renal replacement therapy (RRT) during the ICU stay. Among them, 13 (43%) were alive and still RRT-dependent at day 28.
Chan L, Chaudhary K, Saha A, Chauhan K, et al. AKI in hospitalized patients with COVID-19. Published online September 3, 2020. J Am Soc Nephrol. doi:10.1681/ASN.2020050615
Chaibi K, Dao M, Pham T, Gumucio-Sanguino VD, et al. Severe acute kidney injury in COVID-19 patients with acute respiratory distress syndrome. Published online August 31, 2020. Am J Respir Crit Care Med. doi:10.1164/rccm.202005-1524LE