Table 4.

Cox Regression Analysis About Effects of Different Variables on Overall Survival During Hospitalization

Variables	HR	95% CI	P Value
Aspirin use	0.43	0.25 to 0.75	0.003
PSI V class	1.41	1.03 to 1.93	0.035
Severe sepsis or septic shock	3.44	2.39 to 4.96	<0.001
Pleural effusion	1.53	1.10 to 213	0.011
PaO2/FiO2 ratio <300	2.27	1.58 to 3.26	<0.001

CI indicates confidence interval; HR, hazard ratio; PSI, pneumonia severity index.