Before adjustment, the baseline variables of age, advanced treatment hospital, emergency admission, home healthcare, asthma, cerebrovascular disease, chronic respiratory failure, COPD, liver dysfunction, heart failure, hypertension, interstitial pneumonia, albumin, antithrombin III, heparin, immunoglobulin, insulin, platelet transfusion, red cell transfusion, rhTM, sivelestat administration, vasopressor, zanamivir, peramivir, azithromycin (IV), clarithromycin, carbapenem, new quinolone (IV), IMV days, NPPV, oxygen therapy, PMX, and ICU management differed significantly between the groups. Here, INS is linked to chronic obstructive pulmonary disease.