Table 5.
Baseline data at age 6 years associated with persistent bronchial hyperresponsiveness throughout childhood in male and female adolescents
| Variable | Males (n=71) |
P value | Females (n=37) |
P value | |||
|---|---|---|---|---|---|---|---|
| Persistent BHR (n=25) | No more BHR (n=46) | Persistent BHR (n=15) | No more BHR (n=22) | ||||
| Age at follow-up (yr) | 14±1.5 | 14±1.4 | 1.000 | 14±4.2 | 14±1.3 | 1.000 | |
| Age at the 1st wheeze started (%) | 1.000 | ||||||
| <3 yr | 11 (44) | 22 (48) | 0.807 | 6 (40) | 10 (45) | ||
| ≥3 yr, <6 yr | 14 (56) | 24 (52) | 9 (60) | 12 (55) | |||
| Admission with LRI during 1st 3 years of life (%) | 11 (44) | 14 (30) | 0.303 | 4 (27) | 6 (27) | 1.000 | |
| Combined allergic disease (%) | |||||||
| Allergic rhinitis | 19 (76) | 31 (67) | 0.588 | 13 (87) | 15 (68) | 0.262 | |
| Atopic dermatitis | 12 (48) | 15 (33) | 0.216 | 6 (40) | 8 (36) | 1.000 | |
| Parental allergic disease (%) | 9 (36) | 22 (48) | 0.612 | 2 (13) | 7 (32) | 0.262 | |
| Atopic sensitization (%) | 22 (88) | 40 (87) | 1.000 | 13 (87) | 18 (85) | 1.000 | |
| House dust mite | 20 (90) | 34 (85) | 0.772 | 13 (100) | 18 (100) | 1.000 | |
| Tree pollen | 13 (59) | 21 (53) | 0.807 | 8 (62) | 6 (33) | 0.169 | |
| Grass pollen | 5 (23) | 10 (25) | 0.491 | 6 (46) | 5 (28) | 0.295 | |
| Weed pollen | 8 (36) | 17 (43) | 0.802 | 6 (46) | 3 (17) | 0.128 | |
| Mold | 8 (36) | 3 (8) | 0.013 | 1 (7) | 3 (17) | 0.633 | |
| Pet | 3 (14) | 2 (5) | 0.337 | 3 (23) | 5 (28) | 1.000 | |
| Food | 3 (14) | 6 (15) | 1.000 | 2 (15) | 3 (17) | 1.000 | |
| Polysensitization | 15 (68) | 27 (67) | 1.000 | 9 (69) | 11 (61) | 0.386 | |
| Total serum IgE (IU/mL), median (IQR) | 379 (223–699) | 238 (133–626) | 0.457 | 1101 (123–1885) | 314 (148–612) | 0.294 | |
| Eosinophil (count/mm3), median (IQR) | 561 (313–854) | 444 (259–704) | 0.356 | 553 (253–1227) | 583 (284–565) | 0.152 | |
| Body mass index (kg/m2) | 18.8±5.8 | 18.1±4.3 | 0.546 | 17.4±2.8 | 18.2±2.6 | 0.522 | |
| Pulmonary function test | |||||||
| FEV1 (%predicted) | 94±14.5 | 91±13.6 | 0.359 | 87±9.9 | 98±10.3 | 0.015 | |
| FVC (%predicted) | 93±9.8 | 90±12.6 | 0.231 | 83±10.6 | 91±14.3 | 0.194 | |
| FEV1/FVC (%) | 87±8.6 | 87±9.2 | 0.944 | 94±6.1 | 93±9.6 | 0.731 | |
| <90 | 15 (60) | 25 (54) | 0.803 | 3 (20) | 6 (28) | 0.711 | |
| ≥90 | 10 (40) | 21 (46) | 12 (80) | 16 (72) | |||
| Methacholine PC20 (mg/mL), median (IQR) | 2.3 (1.2–6.5) | 10.5 (6.3–13.8) | 0.000 | 2.6 (1.8–5.8) | 9.8 (6.4–14.3) | 0.007 | |
| <1, 1–4 | 15 (60) | 6 (13) | 10 (67) | 3 (14) | |||
| >4 | 10 (40) | 40 (87) | 5 (33) | 19 (86) | NA | ||
| Methacholine PC20 at follow-up (mg/mL), median (IQR) | 15.2 (3.7–19.2)a) | NA | 14.7 (4.1–20.3) | ||||
Values are presented as mean±standard deviation or number (%) unless otherwise indicated.
BHR, bronchial hyperresponsiveness; LRI, lower respiratory infection; IQR, interquartile range; FEV1, forced expiratory volume in 1 second; FVC, forced vital capacity; PC20, provocative concentration of methacholine causing a 20% fall in forced expiratory volume in 1 second; NA, not available.
a)
P=0.826 vs. female group.
Boldface indicates a statistically significant difference with P<0.05.