Elevated Plasma Level of the Glycolysis Byproduct Methylglyoxal on Admission Is an Independent Biomarker of Mortality in ICU COVID-19 Patients

Biomarkers to identify ICU COVID-19 patients at high risk for mortality are urgently needed for therapeutic care and management. In this study we found that plasma levels of the glycolysis byproduct methylglyoxal (MG) were 4.4-fold and 1.7-fold higher (P<0.0001) upon ICU admission in patients that later died (n=34) compared to uninfected controls (n=30) and those survived (n=31), respectively. The increase in MG was inversely correlated with glutathione ( r 2 =-0.63) and the MG-glutathione degrading glyoxalase-1 ( r 2 =-0.50), and positively correlated with the inflammation markers, SSAO ( r 2  =0.52), TNF-a ( r 2   =0.41), IL-1b ( r 2  =0.25), CRP ( r 2  =0.26) and age ( r 2  =0.20). Logistic regression analysis provides evidence of a significant relationship between the elevated MG upon admission into ICU and death (P<0.0001), with 42% of the death variability explained. From these data we conclude that elevated plasma MG on admission is a novel independent biomarker that predicts ICU COVID-19 patients at high risk of mortality.