TABLE I. Baseline Characteristics of Subjects Completing Lung Function Testing.
| All Subjects Completing Enrollment Lung Function Testing | Subjects Completing Enrollment and Follow-up Lung Function Testing | Subjects Completing only Enrollment Lung Function Testing | |
|---|---|---|---|
| Subjects (n) | 44 | 32 | 12 |
| Gender (male) | 29 (66%) | 22 (69%) | 7 (58%) |
| Race (Caucasian) | 32 (73%) | 26 (81%) | 6 (50%) |
| Mean age at enrollment (months)* | 15.7 ± 5.2 | 15.2 ± 4.9 | 15.5 ± 5.4 |
| Eczema (physician-diagnosed and steroid treated) | 16 (36%) | 10 (31%) | 6 (50%) |
| Family history asthma (1st degree relative) | 23 (52%) | 14 (44%) | 9 (75)% |
| Enviromental tobacco smoke exposure | 12 (27%) | 9 (28%) | 3 (25%) |
| Prior treatment with systemic steroids for wheezing | 33 (75%) | 25 (78%) | 8 (67%) |
| History of ED visit for wheezing | 33 (75%) | 24 (75%) | 9 (75%) |
| History of hospitalization for wheezing | 16 (36%) | 10 (31%) | 6 (50)% |
| History of wheezing apart from viral infections | 16 (36%) | 12 (38%) | 4 (33%) |
| Enrollment SB-eNO (ppb)* | 28.7 ppb ± 16.1 | 27.4 ppb ± 15.3 | 31.2± 19.5 |
| Enrollment FVC (z-score)** | -0.04 (-0.42 to 0.35) | -0.01 (-0.51 to 0.49) | -0.24 (-0.65 to 0.17) |
| Enrollment FEV0.5 (z-score)** | -0.42 (-0.78 to -0.07) | -0.41 (-0.80 to -0.04) | -0.21 (-0.46 to -0.05) |
| Enrollment FEF25-75 (z-score)** | -0.67 (-1.10 to -0.25) | -0.82 (-1.33 to -0.30) | -0.45 (-1.15 to 0.27) |
| Enrollment FEF75 (z-score)** | -0.72 (-1.14 to -0.31) | -0.84 (-1.31 to -0.43) | -0.56 (-1.22 to -0.12) |
Definition of Abbreviations: SB-eNO = single-breath exhaled nitric oxide; ED = emergency department.
*
Data are presented as the mean ± SD
**
Data are presented as the mean ± 95% CI