Predictors of exacerbation frequency in chronic obstructive pulmonary disease

Table 3 Cox analysis of independent prognostic factors for all chronic obstructive pulmonary disease (COPD) patients

Items	B	Wald	Sig.	RR	95.0% CI for RR
Items	B	Wald	Sig.	RR	Lower	Upper
Exacerbation frequency	0.418	11.868	0.001	1.518	1.197	1.926
FEV₁% predicted	-0.015	4.412	0.036	0.985	0.972	0.999
Charlson Index	0.201	7.311	0.007	1.222	1.057	1.413
Age	0.034	4.147	0.042	1.035	1.001	1.070
NPPV	-0.664	8.578	0.003	0.515	0.330	0.803
P_aCO₂	0.022	4.373	0.037	1.023	1.001	1.044
Cor pulmonale	0.390	3.988	0.046	1.477	1.007	2.165
BMI	-0.087	11.383	0.001	0.917	0.872	0.964
Total comorbidities	-0.297	7.790	0.005	0.743	0.603	0.915

RR, relative risk; FEV₁, forced expiratory volume in one second; NPPV, non-invasive positive pressure ventilation; PaCO₂, arterial carbon dioxide tension; BMI, body mass index.

ISSN: 2047-783X