We have no conflicts to disclose.
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Table 1. Demographic and environmental characteristics of case and control subjects.
Yes 178(94.7) 339(90.2) 1.94(0.94-4.00)
Furry/feathery pets
Table 2. Genotype of IL-4 promoter in the relation to asthma.
.
Genotype
Size of the group
No of new asthma cases
Crude
matched odds ratio
(95% CI)
Adjusted*
matched odds ratio
(95% CI)
TT 441 136 1.00 1.00
CT 140 51 1.16 (0.78-1.73) 1.17 (0.76-1.79)
CC 13 1 0.17 (0.02-1.31) 0.20 (0.03-1.66)
*Conditional logistic regression controlling for parents' highest education, parental atopy, duration of
breastfeeding, daily activity, presence of hairy or feathery pets at home and exposure to environmental tobacco smoke (ETS).
Table 3. Correlations of visible mold, mold odor and water damage.
Visible mold Mold odor Water damage
Visible mold 1.00 0.30* 0.07
Mold odor 1.00 0.22*
Water damage 1.00
* Spearman correlation coefficient is significant at the 0.05 level.
Table 4. Matched odds ratios of asthma calculated contrasting the reference category and adjusted for confounding in conditional logistic regression analysis.
Exposure at baseline
Size of the group
No of new asthma cases
Crude
matched odds ratio (95% CI)
Adjusted*matched odds ratio (95%
CI)
Total 564 188 - -
No exposure (reference)
244 63 1.00 1.00
Any exposure indicator
320 125 1.78 (1.25-2.57) 1.43 (1.01-2.13) Mold odor 200 83 2.20 (1.41-3.43) 1.61 (1.02-2.68) Visible mold 137 54 1.82 (1.25-2.64) 1.50 (1.01-2.31) Water damage 20 10 2.57 (0.65-10.1) 2.28 (0.40-13.1)
*Conditional logistic regression controlling for parents' highest education, parental atopy, duration of
breastfeeding, daily activity, presence of hairy or feathery pets at home and exposure to environmental tobacco smoke (ETS).
Table 5. Independent and joint effects of IL-4 promoter and exposure visible mold on the
* Conditional logistic regression controlling for parents' highest education, parental atopy, duration of
breastfeeding, daily activity, presence of hairy or feathery pets at home and exposure to environmental tobacco smoke (ETS).
# p-value for an interaction term between IL-4 promoter (CT vs. TT) and exposure to visible mold exposure (yes vs. no any exposure indicator)
Table 6. Independent and joint effects of IL-4 promoter and exposure to mold odor on the
* Conditional logistic regression controlling for parents' highest education, parental atopy, duration of
breastfeeding, daily activity, presence of hairy or feathery pets at home and exposure to environmental tobacco smoke (ETS).
# p-value for interaction term between IL-4 promoter (CT vs. TT) and exposure to mold odor (yes vs. no any exposure indicator)
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