There were statistically significant differences in the PNI quartiles, including age, sex, CCI, death, hospitalization status, intubation, mechanical ventilation, oxygen, antiviral therapy, hormone therapy, nasal oxygen, lung CT, clinical type, chronic kidney disease, COPD, cerebral infarction, WBC, LY, HGB, PCT, CRP, DD.i, BUN, Scr, CysC, ALB, eGFR, APTT, PT, and hospital outcome. Here, CYGB is linked to brain infarction.