Table 3.
Characteristics of the participants.
| Characteristics | Total n = 701 | Girls n = 357 | Boys n = 344 | p value* |
|---|---|---|---|---|
| Age [years (mean ± SD)] | 9 ± 0.8 | 9 ± 0.8 | 9 ± 0.8 | 0.574 |
| Wheezing symptoms [n (%)] | 66 (9.4) | 34 (9.5) | 32 (9.3) | 0.920 |
| Cough symptoms [n (%)] | 82 (11.7) | 45 (12.6) | 37 (10.8) | 0.446 |
| Asthma [n (%)]** | 75 (10.7) | 47 (13.2) | 28 (8.1) | 0.037 |
| Rhinitis [n (%)] | 81 (13.0) | 36 (11.3) | 45 (14.8) | 0.233 |
| Current rhinitis [n (%)] | 69 (30.4) | 32 (26.8) | 37 (34.3) | 0.611 |
| Atopy [n (%)] | 245 (355) | 128 (36.4) | 117 (34.5) | 0.580 |
| BMI [n (%)] | 0.978 | |||
| Underweight | 33 (4.7) | 17 (4.8) | 16 (4.7) | |
| Normal weight | 478 (68.2) | 242 (67.8) | 236 (68.6) | |
| Overweight | 108 (15.4) | 57 (16.0) | 51 (14.8) | |
| Obese | 82 (11.7) | 41 (11.5) | 41 (11.9) | |
| EBC pH | 6.9 (0.9) | 6.8 (0.9) | 6.9 (0.9) | 0.105 |
| Exhaled NO (ppb) | 17.1 (20.1) | 14.6 (15.5) | 19.6 (23.7) | 0.010 |
| Lung function | ||||
| FVC (%) | 106.8 (15.7) | 113.4 (14.9) | 99.7 (13.2) | < 0.0001 |
| FEV1 (%) | 102.8 (14.6) | 109.3 (13.8) | 95.8 (11.8) | < 0.0001 |
| FEF25–75 (%) | 98.1 (24.3) | 98.6 (24.3) | 97.6 (24.2) | 0.486 |
| Pupillometry | ||||
| Baseline pupil diameter (mm) | 5.3 (0.9) | 5.2 (0.9) | 5.3 (0.9) | 0.137 |
| Final pupil diameter (mm) | 3.4 (0.6) | 3.4 (0.6) | 3.4 (0.6) | 0.745 |
| ACV (mm/s) | −3.9 0.7) | −3.9 (0.7) | −4.0 (0.7) | 0.096 |
| MCV (mm/s) | −5.2 (1.0) | −5.1 (1.0) | −5.4 (1.0) | 0.021 |
| Constriction amplitude (%) | 35.1 (4.8) | 34.5 (4.8) | 35.6 (4.7) | 0.017 |
| ADV (mm/s) | 1.1 (0.3) | 1.2 (0.3) | 1.1 (0.3) | 0.750 |
| T75 (s) | 1.7 (0.7) | 1.7 (0.7) | 1.8 (0.7) | 0.203 |
Data reported as median (interquartile range) unless otherwise stated. BMI: body mass index; FVC: forced vital capacity; FEV1: forced expiratory volume in the first second of FVC; FEF25–75: forced expiratory flow in the middle portion of FVC; EBC: Exhaled breath condensate; ACV: Average constriction velocity; MCV: Maximum constriction velocity; ADV: Average dilation velocity; T75: the total time taken by the pupil to recover 75 of its initial resting diameter after it reached the peak of constriction.