Laboratory Predictors of COVID-19 Mortality: A Retrospective Analysis from Tongji Hospital in Wuhan

Abstract

Background: Novel coronavirus disease 2019 (COVID-19), an acute respiratory disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), rapidly progressed to a global pandemic. Currently, there are limited effective medications approved for this deadly disease.

Objective: To investigate the potential predictors of COVID-19 mortality and risk factors for hyperinflammation in COVID-19.

Methods: Retrospective analysis was carried out in 1,149 patients diagnosed with COVID-19 in Tongji Hospital, Wuhan, China, from 1/13/2020 to 3/15/2020.

Results: We found significant differences in the rates of hyperuricemia (OR: 3.17, 95% CI: 2.13-4.70; p < 0.001) and hypoalbuminemia (OR: 5.68, 95% CI: 3.97-8.32; p < 0.001) between deceased and recovered patients. The percentages of hyperuricemia in deceased patients and recovered patients were 23.6% and 8.9%, respectively, which were higher than the reported age-standardized prevalence of 6.2% in Chinese population. Of note, the percentages of both IL-6 and uric acid levels in survived COVID-19 patients were above 90%, suggesting that they might be good specificity for indicators of mortality in COVID-19 patients. The serum level of uric acid (UA) was positively associated with ferritin, TNF-α, and IL-6 but not with anti-inflammatory cytokine IL-10. In addition, the levels of these proinflammatory cytokines in COVID-19 patients showed a trend of reduction after uric acid lowering therapy.

Conclusions: Our results suggest that uric acid, the end product of purine metabolism, was increased in deceased patients with COVID-19. In addition, the serum level of uric acid was positively associated with inflammatory markers. Uric acid lowering therapy in COVID-19 patients with hyperuricemia may be beneficial.

Figure 1

Uric acid is associated with serum levels of TNF-α, IL-6, and ferritin in COVID-19 patients. (a) Left, serum uric acid (UA) is associated with serum TNF-α level; right, serum TNF-α level in patients with a UA level of lower or higher than 400 μmol/L. (b) Left, association between serum UA and IL-6 levels; right, serum IL-6 level in patients with a UA level of lower or higher than 400 μmol/L. (c) Left, association between serum UA and ferritin levels; right, serum ferritin level in patients with a UA level of lower or higher than 400 μmol/L. (d) Left, association between serum UA and IL-10 levels; right, serum IL-10 level in patients with a UA level of lower or higher than 400 μmol/L. (e) Serum TNF-α level before and after uric acid lowering therapy. (f) Serum IL-6 level before and after uric acid lowering therapy. (g) Serum IL-8 level before and after uric acid lowering therapy.