Blood concentrations of proapoptotic sFas and antiapoptotic Bcl2 and COVID-19 patient mortality

Background: There are no data on circulating concentrations of sFas (proapoptotic protein of extrinsic pathway) and Bcl2 (antiapoptotic protein of intrinsic pathway) in COVID-19 patients. Thus, our objective study was to determine whether an association exists between serum concentrations of sFas and Bcl2 and COVID-19 patient mortality.Methods: This observational and prospective study of COVID-19 patients was performed in eight Intensive Care Units (ICU) from Canary Islands (Spain). Serum levels of sFas and Bcl2 at ICU admission were determined. Mortality at 30 days was the end-point study.Results: Surviving patients (n = 42) compared to non-surviving (n = 11) had lower APACHE-II (p < 0.001), lower SOFA (p = 0.004), lower serum sFas levels (p = 0.001) and higher serum Bcl2 levels (p < 0.001). Logistic regression showed an association between high serum sFas levels and mortality after controlling for APACHE-II (OR = 1.004; 95% CI = 1.101-1.007; p = 0.01) or SOFA (OR = 1.003; 95% CI = 1.101-1.106; p = 0.004), and between low serum Bcl2 levels and mortality after controlling for APACHE-II (OR = 0.927; 95% CI = 0.873-0.984; p = 0.01) or SOFA (OR = 0.949; 95% CI = 0.913-0.987; p = 0.01).Conclusions: Thus, to the best of our knowledge, this is the first study reporting blood levels of sFas and Bcl2 in COVID-19 patients and its association with mortality.