Table 4.

Association of demographic- and lifestyle-related factors with irritable bowel syndrome.

		IBS		χ2, df, p	Binary logistic regression (p)
		No.	%
Gender	Male	11	22.0	4.514, 1, 0.034*	—
	Female	39	78.0		0.096
Age (y)	18–21	26	52.0	0.123, 2, 0.941	—
	22–25	23	46.0		0.594
	>25	1	2.0		0.452
BMI (kg/m2)	18.5–24.9 (normal)	34	68.0	1.076, 3, 0.783	—
	<18.5 (underweight)	6	12.0		0.551
	25–30 (overweight)	9	18.0		0.985
	>30 (obese)	1	2.0		0.341
Tea intake (cups/d)	0	8	16.0	0.559, 4, 0.967	—
	1	16	32.0		0.774
	2	14	28.0		0.767
	3	8	16.0		0.621
	>3	4	8.0		0.807
Coffee intake (cups/d)	0	15	30.0	5.744, 4, 0.219	—
	1	20	40.0		0.426
	2	6	12.0		0.131
	3	7	14.0		0.039*
	>3	2	4.0		0.293
Fatty food consumption (average frequency/wk)	0	0	0.0	4.046, 4, 0.400	—
	1	8	16.0		0.999
	2	19	38.0		0.999
	3	14	28.0		0.999
	>3	9	18.0		0.999
Alcohol consumption (cups/wk)	0	50	100	2.052, 3, 0.562	—
	1	0	0.0		0.999
	2	0	0.0		0.999
	3	0	0.0		0.999
	>3	0	0.0		1.000
Cigarettes consumption (No. of cigarettes/d)	0	50	100	4.708, 5, 0.453	—
	1–5	0	0.0		0.999
	6–10	0	0.0		0.999
	11–15	0	0.0		0.999
	16–20	0	0.0		0.999
	>20	0	0.0		0.999
Waterpipe consumption (average frequency/wk)	0	41	82.0	3.199, 4, 0.525	—
	1	5	10.0		0.065
	2	0	0.0		0.999
	3	1	2.0		0.593
	>3	3	6.0		0.187
Regular NSAIDS intake (pills/mo)	0–5	41	82.0	5.822, 4, 0.213	—
	6–10	6	12.0		0.684
	11–15	1	2.0		0.688
	16–20	2	4.0		0.060
	>20	0	0.0		1.000

BMI = body mass index; df = degree of freedom; IBS = irritable bowel syndrome; NSAIDs = nonsteroidal antiinflammatory drugs.

^*p < 0.05; for the χ² or binary logistic regression test investigating the association between each risk factor and irritable bowel syndrome.