NPPB and susceptibility to pneumonia measurement: The results showed that age (incidence rate ratio (IRR) 1.08, 95% CI 1.02–1.16, P value 0.013), malignancy (IRR 6.0, 95% CI 2.14–16.87, P value 0.001), NT-pro BNP ≥1800 pg/ml (IRR 6.09, 95% CI 2.2–16.88, P value 0.001), and pneumonia on CT scan (IRR 3.52, 95% CI 1.40–8.81, P value 0.007) were independent risk factors for hospital mortality.