Table 4.

Incidences and HRs of coronary artery disease, cardiac dysrhythmia and heart failure in the ACOS cohort stratified by AE-COPD

Variable	N	Event	PY	Rate	Crude HR (95% CI)	Adjusted HR† (95% CI)
Coronary artery disease
Non-ACOS	11 625	1450	72 458	20.0	1 (reference)	1 (reference)
All ACOS
Without AE-COPD	4373	934	24 507	38.1	1.89 (1.74 to 2.05)***	1.85 (1.70 to 2.01)***
With AE-COPD	1441	213	8073	26.4	1.31 (1.13 to 1.51)***	1.05 (0.90 to 1.21)
Cardiac dysrhythmia
Non-ACOS	11 625	862	75 887	11.4	1 (reference)	1 (reference)
All ACOS
Without AE-COPD	4373	482	27 336	17.6	1.55 (1.39 to 1.73)***	1.57 (1.40 to 1.77)***
With AE-COPD	1441	140	8448	16.6	1.45 (1.22 to 1.74)***	1.11 (0.93 to 1.34)
Heart failure
Non-ACOS	11 625	616	77 072	7.99	1 (reference)	1 (reference)
All ACOS
Without AE-COPD	4373	438	27 636	15.9	1.98 (1.75 to 2.24)***	2.07 (1.82 to 2.35)***
With AE-COPD	1441	150	8418	17.8	2.22 (1.86 to 2.65)***	1.64 (1.36 to 1.97)***

Rate denotes incidence rate (per 1000 person-years) and Crude HR denotes relative HR.

*p<0.05, **p<0.01, ***p<0.001.

†Covariables found to be significantly associated with coronary artery disease, cardiac dysrhythmia and heart failure in the univariate Cox proportional regression model were further analysed using a multivariate Cox proportional regression model.

ACOS, asthma–chronic obstructive pulmonary disease overlap syndrome; AE-COPD, acute exacerbation of chronic obstructive pulmonary disease; PY, person-years.