IL6 and COVID-19: For example, IL-6, CRP, and hypertension were ideal predictors for the progression of COVID-19 (Zhu Z. et al., 2020), while older age, high Sequential Organ Failure Assessment (SOFA) score and D-dimer greater than 1 μg/L were risk factors for in-hospital death in COVID-19 patients (Zhou F. et al., 2020).