IL6 and acute kidney injury: Based on univariable Cox regression analysis, risk factors associated with mortality in the young-old group included: respiratory rate, stomachache symptoms, symptoms of confusion, ARDS, AKI, respiratory weakness, lactate, FDP, urea, creatinine, AST, TBIL, lactate dehydrogenase, creatine kinase mb, IL6, procalcitonin, non-invasive mechanical ventilation and invasive mechanical ventilation (compared with supplemental oxygen) is related to death.