Table 2.

Variables associated with all-cause mortality of COPD in a Cox proportional hazard regression model

Variable	Unadjusted		Fully adjusted
	HR (95% CI)	P-value	HR (95% CI)	P-value
Age	1.093 (1.056–1.132)	<0.001	1.139 (1.077–1.204)	<0.001
Years of smoking	1.043 (1.015–1.071)	0.002	0.984 (0.950–1.020)	0.389
Age of quitting smoking	1.091 (1.057–1.126)	<0.001	1.078 (1.025–1.113)	0.003
Onset of symptoms	1.036 (1.011–1.062)	0.005	0.975 (0.940–1.011)	0.166
FEV1% predicted	1.020 (1.004–1.036)	0.028	1.020 (1.002–1.038)	0.025

Note: Statistically significant values are shown in bold.

Abbreviations: CI, confidence interval; FEV₁, forced expiratory volume in one second; HR, Hazard ratio.