Table 1.
Baseline Characteristics.
| Total, N = 330 |
Missing | Males, N = 161 (49%) |
Missing | Females, N = 169 (51%) |
Missing | P | ||
|---|---|---|---|---|---|---|---|---|
| At 18 years | ||||||||
| Caucasian | 318 (96%) | 0 | 153 (95%) | 0 | 165 (98%) | 0 | 0.333 | |
| Age (yr) | 17.6 (17.4–17.9) | 0 | 17.6 (17.4–17.9) | 0 | 17.5 (17.4–18) | 0 | 0.598 | |
| Height (cm) | 175 (9.4) | 0 | 182 (6.9) | 0 | 168.5 (6.2) | 0 | < 0.001 | |
| Weight (kg) | 67.8 (61.4–77.2) | 0 | 72.7 (65.9–82) | 0 | 63.9 (57.9–70.5) | 0 | < 0.001 | |
| Asthma diagnosis | 101 (31%) | 0 | 51 (32%) | 0 | 50 (30%) | 0 | 0.77 | |
| Persistent N (%) | 35 (11%) | 0 | 19 (12%) | 0 | 16 (9%) | 0 | 0.61 | |
| Intermitent N (%) | 78 (24%) | 0 | 39 (24%) | 0 | 39 (23%) | 0 | 0.908 | |
| Atopic dermatitis | 34 (10%) | 0 | 12 (7%) | 0 | 22 (13%) | 0 | 0.139 | |
| Allergic rhinitis | 138 (42%) | 0 | 71 (44%) | 0 | 67 (40%) | 0 | 0.479 | |
| HGS (kg) | 34.7 (10.7) | 1 | 42.7 (8.8) | 1 | 27.2 (5.4) | 0 | < 0.001 | |
| FEV1 (L) | 3.9 (0.8) | 1 | 4.5 (0.6) | 1 | 3.3 (0.5) | 0 | < 0.001 | |
| FVC (L) | 4.4 (0.9) | 1 | 5.1 (0.7) | 1 | 3.7 (0.5) | 0 | < 0.001 | |
| MMEF (L) | 4.2 (1.1) | 1 | 4.8 (1.1) | 1 | 3.7 (0.9) | 0 | < 0.001 | |
| FEV1/FVC | 0.9 (0.9–42.8) | 1 | 0.89 (0.11) | 1 | 0.91 (0.1) | 0 | 0.043 | |
| sRaw (kPa/s) | 1.11 (0.9–1.3) | 2 | 1.16 (1–1.3) | 1 | 1.06 (0.9–1.2) | 0 | 0.006 | |
| PD20 (µg) | 238.6 (141.9–714.8) | 79 | 310.9 (161.6–1073.1) | 39 | 199.2 (128.3–464.6) | 40 | 0.015 | |
| FeNO (ppb) | 16.4 (11.2–26.7) | 3 | 20.9 (13.1–31.6) | 0 | 13.9 (10.1–23.3) | 3 | < 0.001 | |
| Key | ||||||||
Data are presented as n (%) for categorical variables, mean (SD) for continuous normally distributed variables, and median (Q25:Q75) for continuous non-normally distributed variables. For categorical variables the Chi-squared test was used, for continuous normally distributed variables. Two sample t-tests were used and for normally distributed continuous variables and Wilcoxon rank sum test was used for variables not normally distributed.
FeNO = Fractional Exhaled Nitric Oxide, FEV1 = Forced Expiratory Volume 1 second, FVC = Forced Vital Capacity, HGS = Handgrip Strength, MMEF = Maximal Mid-expiratory Flow, PD20 = Provocation Dose of methacholine causing a drop of 20% in FEV1, sRaw = Specific Airway Resistance.