The univariate Cox regression analysis identified the following independent factors that affect 30-day mortality with HAP (Table 3): age greater than 70 years, presence of diabetes mellitus and COPD, gastric tube intubation, administration of proton-pump inhibitor, blood albumin level less than 30 g/l, elevated neutrophil-to-lymphocyte ratio, antibiotics therapy in the preceding 90 days, ICU admission, blood lymphocyte count less than 0.8 × 109/L, elevated BUN/ALB levels, and presence of MDR pathogens. Here, ALB is linked to chronic obstructive pulmonary disease.