Association between chronic bronchitis (CB+) and the risk of all-cause death in chronic obstructive pulmonary disease (COPD), additionally stratified according to sex
| Model 1 | Model 2 | |||
| HR (95% CI) | p-value | HR (95% CI) | p-value | |
| Subjects n | 924 | 878 | ||
| COPD CB+ | 1.45 (1.14–1.84) | 0.002 | 1.33 (1.04–1.71) | 0.024 |
| Male COPD CB+ | 1.32 (0.98–1.78) | 0.072 | 1.22 (0.89–1.65) | 0.212 |
| Female COPD CB+ | 1.69 (1.14–2.53) | 0.010 | 1.57 (1.03–2.40) | 0.036 |
Model 1: age and sex# adjusted; model 2: adjusted for age, sex# and pack-years of cigarette smoking. HR: hazard ratio. #: unstratified analyses only.