Table 3.

Hospital Utilization According to Use of Oral Methylxanthines and/or LTRA in Mild-to-Moderate COPD

Variables	Methylxanthines and/or LTRA User (n=279)	Methylxanthines and/or LTRA Non-User (n=1990)	P-value
Frequency of acute exacerbation, times/yr	0.4 ± 0.30	0.2 ± 0.15	<0.001
Total OPD visit	12.9 ± 20.20	4.9 ± 8.82	<0.001
OPD visit, times/yr	2.2 ± 3.37	0.8 ± 1.47	<0.001
ER visit, times/yr	0.2 ± 0.14	0.2 ± 0.06	0.044
Hospitalization, times/yr	0.3 ± 0.29	0.2 ± 0.15	<0.001
ICU, times/yr	0.2 ± 0.07	0.2 ± 0.0	0.083
Total used days	21.2 ± 27.92	13.2 ± 19.16	<0.001
Cost/year, USD	346,315.0 ± 671,806.1	370,182.0 ± 632,665.0	0.324

Abbreviations: OPD, outpatient department; ER, emergency room; ICU, intensive care unit; USD, United States dollar; yr, year.