Table 2

 Unadjusted and adjusted odds ratios (ORs) and 95% confidence intervals (CIs) for wheezing phenotypes* (transient early wheeze, persistent wheeze, and late onset wheeze (0–42 months)) according to total chemical burden (TCB) score measured during pregnancy (bottom decile versus top decile)

Wheezing phenotypeBottom decile of TCB% (N)Top decile of TCB% (N)Unadjusted OR(95% CI)(N = 7019)Unadjusted p valueAdjusted OR**(95% CI)(N = 5691)Adjusted p value
*Never wheezed 0–42 months. Transient early wheeze: wheeze 0–6 months and no wheeze 6–42 months. Persistent wheeze: wheeze 6–18 months, 18–30 months and 30–42 months. Late onset wheeze: wheeze onset 30–42 months.
**Adjusted for weekend exposure to environmental tobacco smoke at 6 months, maternal smoking during pregnancy, maternal history of asthma, maternal parity, crowding in the home, sex, contact with pets, damp housing, maternal age at delivery, maternal educational attainment, housing tenure, hours mother worked outside home, month of returning chemical usage questionnaire, and duration of breastfeeding.
Never wheezed74.9 (603)66.9 (338)1 (reference)1 (reference)
Transient early wheeze18.8 (151)19.0 (96)1.13 (0.90 to 1.50)0.40.94 (0.60 to 1.40)0.7
Persistent wheeze4.0 (32)10.1 (51)2.84 (1.79 to 4.51)<0.00012.30 (1.20 to 4.39)0.012
Late onset wheeze2.4 (19)4.0 (20)1.88 (0.99 to 3.57)0.052.02 (0.80 to 5.15)0.14