Table 7. Joint effects of carpet use and IL-13 genotypes on asthma phenotypes among children.

		Asthma		Wheeze		Early-onset asthma†		Late-onset asthma‡
	Carpet use	OR	95%CI	OR	95%CI	OR	95%CI	OR	95%CI
SNP rs1800925
CC	No	1		1		1		1
CC	Yes	0.7	(0.4,1.2)	0.7	(0.5,1.2)	0.5	(0.2,1.2)	1.1	(0.5,2.6)
CT or TT	No	1.1	(0.8,1.5)	1.2	(0.9,1.5)	1.2	(0.8,1.7)	1.0	(0.6,1.7)
CT or TT	Yes	1.4	(0.7,3.0)	2.0	(1.2,3.6)	0.5	(0.1,1.9)	3.9	(1.7,9.1)
P for interaction		0.17		0.03		0.75		0.04
SNP rs2066960
CC	No	1		1		1		1
CC	Yes	0.8	(0.3,1.9)	1.3	(0.7,2.3)	0.6	(0.2,2.1)	1.1	(0.3,3.7)
CA or AA	No	1.0	(0.7,1.2)	0.9	(0.7,1.1)	1.1	(0.8,1.6)	0.7	(0.4,1.0)
CA or AA	Yes	0.8	(0.5,1.5)	0.8	(0.5,1.3)	0.4	(0.2,1.1)	1.5	(0.7,3.1)
P for interaction		0.84		0.30		0.52		0.28
SNP rs20541
CC	No	1		1		1		1
CC	Yes	0.6	(0.3,1.3)	0.7	(0.4,1.3)	0.6	(0.3,1.6)	0.7	(0.2,2.4)
CT or TT	No	1.0	(0.8,1.3)	1.1	(0.9,1.4)	1.2	(0.9,1.6)	0.8	(0.5,1.3)
CT or TT	Yes	1.1	(0.6,2.0)	1.4	(0.9,2.3)	0.4	(0.1,1.2)	2.5	(1.2,5.2)
P for interaction		0.30		0.15		0.36		0.03
SNP rs848
GG	No	1		1		1		1
GG	Yes	0.6	(0.3,1.3)	0.7	(0.4,1.3)	0.6	(0.2,1.6)	0.7	(0.2,2.2)
GT or TT	No	1.0	(0.8,1.3)	1.2	(0.9,1.4)	1.2	(0.9,1.6)	0.8	(0.5,1.2)
GT or TT	Yes	1.1	(0.6,2.0)	1.5	(0.9,2.4)	0.4	(0.1,1.2)	2.6	(1.2,5.3)
P for interaction		0.26		0.13		0.39		0.02

Models are adjusted for age, sex, parental history of asthma, parental history of atopy, in utero exposures to maternal smoking, ETS, dampness, incense burning, pet ownership at home and community.

^†Early-onset: asthma diagnosed ≦5 yr of age.

^‡Late-onset: asthma diagnosed >5 yr of age.