Table 1:
Association between sRaw and Sensitization, Atopy Phenotypes Defined on the Basis of Patterns of Sensitization over Time, Assuming That Atopy Phenotypes Have Different Rates of Change in sRaw over Time
| sRaw (kPa ⋅ s−1) | P Value | |
|---|---|---|
| Model A: Sensitization | ||
| Reference group (no sensitization, sRaw at age 3), mean (SE) | 1.129 (0.012) | |
| Sensitized (skin prick test), estimated difference (SE) | +0.052 (0.016) | 0.002 |
| Age (effect of time, per year), estimated difference (SE) | +0.022 (0.002) | <0.001 |
| Model B: Atopy phenotypes | ||
| Reference group (no sensitization, sRaw at age 3), mean (SE) | 1.057 (0.017) | |
| Non–dust mite, estimated difference (SE) | +0.013 (0.027) | 0.63 |
| Dust mite, estimated difference (SE) | +0.001 (0.037) | 0.98 |
| Multiple late, estimated difference (SE) | +0.028 (0.021) | 0.18 |
| Multiple early, estimated difference (SE) | +0.116 (0.026) | <0.001 |
| Age (effect of time, per year), estimated difference (SE) | +0.023 (0.002) | <0.001 |
| Model C: Interaction of atopy phenotypes with time | ||
| Reference group (no sensitization, sRaw at age 3), mean (SE) | +1.130 (0.011) | |
| Non–dust mite, estimated difference (SE) | +0.013 (0.027) | 0.29 |
| Dust mite, estimated difference (SE) | +0.001 (0.037) | 0.65 |
| Multiple late, estimated difference (SE) | +0.003 (0.024) | 0.91 |
| Multiple early, estimated difference (SE) | +0.092 (0.029) | 0.002 |
| Age (effect of time, per year), estimated difference (SE) | +0.018 (0.002) | <0.001 |
| Interaction non–dust mite × age (effect of time, per year among children with non–dust mite atopy), estimated difference (SE) | −0.003 (0.005) | 0.52 |
| Interaction dust mite × age (effect of time, per year among children with dust mite atopy), estimated difference (SE) | +0.000 (0.007) | 0.97 |
| Interaction multiple late × age (effect of time, per year among children with multiple late atopy), estimated difference (SE) | +0.008 (0.004) | 0.047 |
| Interaction multiple early × age (effect of time, per year among children with multiple early atopy), estimated difference (SE) | +0.011 (0.005) | 0.032 |
Definition of abbreviation: sRaw = specific airway resistance.
sRaw (mean, SE) for children in the reference group (no sensitization, sRaw at age 3 yr) is presented in the first line. For each model we present the estimated difference in sRaw among children with a given characteristic (e.g., different atopy phenotypes in Model B) compared with children in the reference group. The estimate of age shows the expected increase in sRaw for every year increase in age.