Modification of additive effect between vitamins and ETS on childhood asthma risk according to GSTP1 polymorphism : a cross -sectional study

Table 3 Associations among antioxidant nutrient intake, environmental tobacco smoke, and prevalence of asthma symptoms

Variable		Wheeze symptom in the previous 12 months		Asthma diagnosis
Variable		n (%)	aOR^f (95 % CI)	n (%)	aOR^f (95 % CI)
Antioxidant intake^h
Vitamin A^a	Low	46/725 (6.34)	1.00	74/720 (10.28)	1.00
Vitamin A^a	High	17/360 (4.72)	0.53 (0.24, 1.17)	36/362 (9.94)	0.77 (0.44, 1.34)
Retinol^b	Low	42/722 (5.82)	1.00	59/714 (8.26)	1.00
Retinol^b	High	21/363 (5.79)	0.59 (0.27, 1.28)	51/368 (13.86)	1.51 (0.88, 2.60)
Carotene^c	Low	41/725 (5.66)	1.00	71/723 (9.82)	1.00
Carotene^c	High	22/360 (6.11)	0.95 (0.46, 2.00)	39/359 (10.86)	0.95 (0.55, 1.62)
Vitamin C^d	Low	38/725 (5.24)	1.00	66/727 (9.08)	1.00
Vitamin C^d	High	25/360 (6.94)	0.97 (0.45, 2.07)	44/355 (12.39)	1.14 (0.66, 1.97)
Vitamin E^e	Low	34/725 (4.69)	1.00	60/726 (8.26)	1.00
Vitamin E^e	High	29/360 (8.06)	1.67 (0.72, 3.87)	50/356 (14.04)	1.57 (0.85, 2.89)
Environmental tobacco smoke^g	No	31/683 (4.54)	1.00	60/674 (8.90)	1.00
Environmental tobacco smoke^g	Yes	31/386 (8.03)	2.48 (1.29, 4.76)*	50/390 (12.82)	1.91 (1.19, 3.06)*

aOR adjusted odds ratio, BMI body mass index
^aCut-off point for dietary vitamin A, 803.84 μg/day
^bCut-off point for dietary retinol, 253.69 μg/day
^cCut-off point for dietary β-carotene, 3081.38 μg/day
^dCut-off point for dietary vitamin C, 81.4 mg/day
^eCut-off point for dietary vitamin E, 14.68 mg/day
^faOR: Adjusted by age, sex, BMI (continuous), parental history of asthma, exposure to environmental tobacco smoke, maternal education, household income, and log-transformed total energy intake
^gaOR: Adjusted for the same confounders as above with the exception of environmental tobacco smoke
^hNutrients were adjusted for total energy intake
*P-value < 0.01

ISSN: 1471-2466