Table 3.
Clinical characteristics of male and female adolescents with or without bronchial hyperresponsiveness
| Characteristic | Males (n=149) |
P value | Females (n=66) |
P value | |||
|---|---|---|---|---|---|---|---|
| BHR (+) (n=78) | BHR (-) (n=71) | BHR (+) (n=35) | BHR (-) (n=31) | ||||
| Age (yr) | 14±1.9 | 14±2.3 | 1.000 | 15±3.2 | 14±1.8 | 0.424 | |
| Age at the 1st wheeze started (%) | |||||||
| <3 yr | 29 (37) | 29 (41) | 0.447 | 13 (37) | 14 (45) | 0.618 | |
| ≥3 yr, <6 yr | 10 (13) | 12 (17) | 0.483 | 4 (11) | 5 (13) | 0.892 | |
| ≥6 yr | 39 (50) | 30 (42) | 0.354 | 18 (52) | 12 (39) | 0.705 | |
| Admission with LRI during 1st 3 years of life (%) | 26 (33) | 26 (37) | 0.632 | 11 (31) | 12 (42) | 0.446 | |
| Combined allergic disease | |||||||
| Allergic rhinitis | 58 (74) | 54 (77) | 0.705 | 23 (66) | 21 (71) | 0.652 | |
| Atopic dermatitis | 39 (50) | 27 (38) | 0.082 | 16 (46) | 11 (35) | 0.448 | |
| Parental allergic disease | 32 (41) | 26 (38) | 0.558 | 13 (40) | 10 (32) | 0.541 | |
| Atopic sensitization | 74 (95) | 62 (86) | 0.091 | 32 (91) | 28 (90) | 0.947 | |
| House dust mite | 65 (88) | 52 (84) | 0.951 | 32 (100) | 25 (89) | 0.246 | |
| Tree pollen | 34 (46) | 38 (61) | 0.081 | 13 (41) | 13 (46) | 0.702 | |
| Grass pollen | 19 (26) | 17 (27) | 0.774 | 6 (18) | 9 (32) | 0.348 | |
| Weed pollen | 29 (39) | 28 (45) | 0.482 | 8 (25) | 10 (35) | 0.645 | |
| Mold | 26 (35) | 13 (21) | 0.047 | 8 (25) | 6 (21) | 0.549 | |
| Pet | 28 (38) | 13 (21) | 0.041 | 11 (34) | 6 (21) | 0.149 | |
| Food | 10 (14) | 13 (21) | 0.257 | 4 (13) | 4 (14) | 0.644 | |
| Polysensitization | 48 (65) | 46 (74) | 0.203 | 20 (63) | 20 (71) | 0.518 | |
| Total serum IgE (IU/mL), median (IQR) | 388 (184–827) | 321 (132–639) | 0.915 | 582 (228–1,393) | 403 (196–818) | 0.406 | |
| Eosinophil (count/mm3), median (IQR) | 561 (279–753) | 426 (234–691) | 0.070 | 539 (275–891) | 354 (171–536) | 0.067 | |
| Body mass index (kg/m2) | 22.3±7.6 | 21.9±4.1 | 0.902 | 21.2±4.1 | 21.4±4.0 | 0.809 | |
| Asthma severitya), median (range) | 2 (1–4) | 1 (1–3) | 0.079 | 2 (1–4) | 1 (1–4) | 0.052 | |
| Pulmonary function test | |||||||
| FEV1 (%predicted) | 92±14.5 | 94±18.2 | 0.476 | 91±14.5 | 98±12.6 | 0.024 | |
| FVC (%predicted) | 95±11.8 | 93±16.3 | 0.475 | 92±17.2 | 97±15.1 | 0.217 | |
| FEV1/FVC (%) | 83±10.3 | 85±8.4 | 0.327 | 85±11.1 | 89±6.4 | 0.041 | |
| <90 | 60 (77) | 46 (65) | 0.108 | 27 (77) | 12 (39) | 0.005 | |
| ≥90 | 18 (23) | 25 (35) | - | 8 (23) | 19 (61) | - | |
| Methacholine PC20 (mg/mL), median (IQR) | 5.6 (1.3–16)b) | NA | - | 5 (2.3–16) | NA | - | |
| <1 | 17 (22) | - | - | 8 (23) | - | - | |
| 1–4 | 16 (20) | - | - | 8 (23) | - | - | |
| >4 | 45 (58) | - | - | 19 (54) | - | - | |
| Current asthmc) | 51 (65) | 25 (35) | 0.008 | 24 (68) | 7 (23) | 0.003 | |
| PC20, <1 | 12/17 (70) | - | - | 8/8 (100) | - | - | |
| PC20, 1–4 | 14/16 (87) | - | - | 6/8 (75) | - | - | |
| PC20, >4 | 25/45 (55) | - | - | 10/19 (53) | - | - | |
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.
Asthma severity: 1, mild-intermittent; 2, mild-persistent; 3, moderate-persistent; 4, severe-persistent.
P=0.72 vs. the female group.
Current asthma: episodes of wheeze verified by physicians or asthma exacerbation in the previous year.
Boldface indicates a statistically significant difference with P<0.05.