TABLE I.
Covariate | Control subjects (n = 327) |
Cases (n = 351) |
---|---|---|
Age (y) | 10.5 (2.7) | 10.0 (2.6)‡ |
Female sex | 168 (51.4%) | 150 (42.7%)‡ |
Body mass index (z score) | 0.5 (1.1) | 0.7 (1.2) |
Total IgE (IU/mL)§ | 151.4 (4.7) | 295.1 (4.8)‡ |
Atopy (≥1 positive allergen-specific IgE) | 143 (49.8%) | 210 (68.9%)‡ |
Exposure to ETS in utero or before age 2 y | 131 (40.2%) | 174 (49.6%)‡ |
Current exposure to ETS | 113 (34.6%) | 155 (44.2%)‡ |
Household income <$15,000/y | 196 (62.8%) | 225 (65.4%) |
No parent graduated from high school | 64 (19.6%) | 63 (18.0%) |
No private or employer-based health insurance | 205 (62.7%) | 239 (68.1%) |
Maternal history of asthma | 67 (20.8%) | 172 (49.3%)‡ |
Maternal history of asthma, allergic rhinitis, or eczema | 86 (26.7%) | 190 (54.8%)‡ |
Low birth weight (<2500 g) | 14 (4.5%) | 18 (5.2%) |
Birth by cesarean section | 108 (33.4%) | 131 (37.4%) |
Prematurity | 15 (4.6%) | 31 (8.9%)‡ |
Prematurity requiring NICU admission | 6 (1.9%) | 21 (6.0%)‡ |
FEV1 (L)‖ | 2.0 (0.7) | 1.9 (0.7)‡ |
FEV1/FVC ratio | 0.84 (0.1) | 0.81 (0.1)‡ |
Data are presented as numbers (percentages) for binary variables or means (SDs) for continuous variables.
Percentages were calculated for children with complete data. For example, 592 (287 control subjects and 305 cases) of the 678 participating children had allergen-specific IgE.
P < .05 for the comparisons between groups (performed by using 2-sample t tests or Fisher exact tests, as appropriate).
Total IgE transformed to a logarithmic (log10) scale. Results are shown as geometric means (SDs).
FEV1 values are presented as absolute values because of lack of predicted values for Puerto Rican subjects.