Table 4. Hazard ratios of irritable bowel syndrome associated with mean number of annual emergency room visits for asthma.

	Events	Crude HR (95% CI)	Adjusted HR† (95% CI)
Non-asthma	3593	1 (Reference)	1 (Reference)
Times of emergency room visit
<1	1591	1.81 (1.71–1.92)***	1.51 (1.42–1.62)***
1−2	30	7.97 (5.56–11.4)***	6.23 (4.34–8.95)***
>2	51	30.3 (22.9–39.9)***	20.7 (15.6–27.4)***
p for trend		<0.001	<0.001

HR = hazard ratio, CI = confidence interval;

^† Model was adjusted for age, sex, and comorbidities of COPD, GERD, allergic rhinitis, chronic sinusitis, atopic dermatitis, anxiety, depression, and obesity;

*** p < 0.001.