Higher urea-to-albumin ratio is associated with mortality risk in critically ill COVID-19 patients

Abstract

Background: This study aimed to evaluate the ability of the urea-to-albumin ratio (UAR) to predict mortality in critically ill coronavirus disease 2019 (COVID-19) patients.

Methods: This retrospective study included adult patients admitted with COVID-19 at two intensive care units (ICUs) at the University Hospital. Serum urea and albumin concentrations at ICU admission were used to calculate the UAR. All patients were followed up during hospitalization, and the ICU mortality rate was recorded.

Results: Two hundred and eleven patients were evaluated. The mean age was 57.8 ± 15.5 years, and 54% were male. Approximately 84.4% of patients were considered to be at nutritional risk by the NRS 2002, and the median UAR was 18.3 (10.5-34.8). The length of stay in the ICU was 10 (6-16) days, 38.4% of the patients required dialysis, and 64.9% died. Age, male sex, need of hemodialysis, lactate level, and inflammatory parameters were associated with higher mortality. Patients non-survivors had a higher UAR (23.7 [13.6-41.8] vs. 10.9 [8.5-16.8]; p < 0.001). The cutoff point with the best performance of UAR in the ROC curve for predicting mortality was ≥12.17 (AUC: 0.7201; CI 95%: 0.656-0.784). Additionally, the risk of mortality was 2.00-fold in the group of patients with UAR ≥12.17 (HR: 2.00 CI: 1.274-3.149; p = 0.003) and remained significant after adjusted analyzes (models 1 and 2).

Conclusion: Our data suggest that a UAR ≥12.17 increased the risk of mortality by 2.00-fold in critically ill COVID-19 patients.

Keywords: COVID-19; Critical illness; Mortality; Urea/albumin ratio.

Fig. 1

ROC curve for the association between urea to albumin ratio and ICU mortality. The area under the ROC curve: 0.775 (CI 95%: 0.7088–0.8420; p < 0.001).