Table 2. Asthma-related clinical characteristics according to inhaled corticosteroid use.

Characteristics		ICS (−)		ICS (+)		P value
		No.	%	No.	%
Total		447,855	100.0	281,488	100.0
Outpatient visit ≥ 3 times		272,904	60.9	223,656	79.5	< 0.001
No. of outpatient visits		4.6 ± 5.33		6.4 ± 6.88		< 0.001
ER visit		2,197	0.5	14,560	5.2	< 0.001
No. of ER visits		1.2 ± 1.23		1.4 ± 2.22		< 0.001
Hospitalization		5,090	1.1	25,111	8.9	< 0.001
No. of hospitalizations		1.3 ± 0.77		1.5 ± 1.08		< 0.001
ICU admission		322	0.1	2,232	0.8	< 0.001
No. of ICU admissions		1.1 ± 0.32		1.2 ± 0.53		< 0.001
Mean hospitalized days		13.2 ± 14.16		15.5 ± 18.28		< 0.001
Complications
	Pneumonia	43,978	9.8	50,237	17.8	< 0.001
	Empyema	92	0.02	284	0.10	< 0.001
	ARDS, acute respiratory failure	72	0.02	131	0.05	< 0.001
	Pneumothorax	175	0.04	541	0.19	< 0.001
	Pneumomediastinum	24	0.01	48	0.02	< 0.001

ICS, inhaled corticosteroids; ER, emergency room; ICU, intensive care unit; ARDS, acute respiratory distress syndrome.