Table 1

Comparisons of baseline demographic factors and comorbidities between study enrollees with and without COPD

Variable	Non-COPD group n=19 959		COPD group n=19 959		p Value
Variable	n	%	n	%
Age, years					>0.99
40–54	5141	25.8	5141	25.8
55–69	7274	36.4	7274	36.4
≥70	7544	37.8	7544	37.8
Mean (SD)*	63.8	(12.4)	64.5	(12.2)	<0.001
Comorbidity
DM	2595	13.0	3209	16.1	<0.001
Dyslipidemia	3267	16.4	4621	23.2	<0.001
Hypertension	7672	38.4	10 432	52.3	<0.001
Heart failure	375	1.88	981	4.92	<0.001
CAD	3141	15.7	5739	28.8	<0.001
Medication
Use of tiotropium†	0	0.00	39	0.20	<0.001
Use of ipratropium†	2	0.01	135	0.68	<0.001
Annual OPD visits					<0.001
<30	16 050	80.4	10 869	54.5
≥30	3909	19.6	9090	45.5
Mean (SD)*	18.9	(17.1)	32.8	(22.4)	<0.001

*Student's t-test.
†Fisher's exact test.
CAD, coronary artery disease; COPD, chronic obstructive pulmonary disease; DM, diabetes mellitus; OPD, outpatient department.