Baseline demographic characteristics and medical history
School-aged | Preschool | |||||
Severe asthma cohort | Mild/moderate asthma cohort | p-value | Severe wheeze cohort | Mild/moderate wheeze cohort | p-value | |
Patients n | 97 | 43 | 77 | 54 | ||
Demographic details | ||||||
Female | 46/97 (47.4%) | 16/43 (37.2%) | 0.263 | 27/77 (35.1%) | 20/54 (37.0%) | 0.817 |
Age years | 12.21±0.31 (n=97) | 11.26±0.48 (n=43) | 0.583ƒ | 3.56±0.14 (n=77) | 3.46±0.16 (n=54) | 0.410ƒ |
White | 74/97 (76.3%) | 32/43 (74.4%) | 0.812 | 62/77 (80.5%) | 48/54 (88.9%) | 0.204 |
Mother smoked during pregnancy | 14/94 (14.9%) | 6/43 (14.0%) | 0.885 | 10/77 (13.0%) | 1/54 (1.9%) | 0.052 |
Smoker | 0/97 (0.0%) | 0/43 (0.0%) | NA | 0/77 (0.0%) | 0/54 (0.0%) | NA |
Second-hand smoke exposure | 21/92 (22.8%) | 9/43 (20.9%) | 0.805 | 12/76 (15.8%) | 9/54 (16.7%) | 0.893 |
Urinary cotinine present | 8/93 (8.6%) | 5/38 (13.2%) | 0.432 | 12/62 (19.4%) | 2/46 (4.3%) | 0.035 |
Anthropometry# | ||||||
Height cm | 152.82±1.65 (n=97) | 148.12±2.58 (n=43) | 0.604ƒ | 102.88±1.13 (n=76) | 103.62±1.52 (n=53) | 0.068ƒ |
Height z-score | 0.68±0.34 (n=97) | 0.58±0.2 (n=43) | 0.851 | 1.14±0.16 (n=76) | 1.53±0.18 (n=53) | 0.108 |
Weight kg | 51.74±1.85 (n=97) | 43.64±2.3 (n=43) | 0.067ƒ | 17.63±0.48 (n=77) | 17.27±0.46 (n=53) | 0.687ƒ |
Weight z-score | 1.14±0.21 (n=97) | 0.66±0.19 (n=43) | 0.167 | 0.94±0.14 (n=77) | 0.92±0.13 (n=53) | 0.930 |
BMI kg·m−2 | 21.52±0.5 (n=97) | 19.21±0.5 (n=43) | 0.035ƒ | 16.56±0.25 (n=76) | 15.99±0.15 (n=53) | 0.071ƒ |
BMI z-score | 0.99±0.13 (n=97) | 0.56±0.17 (n=43) | 0.058 | 0.26±0.15 (n=76) | −0.04±0.1 (n=53) | 0.133 |
Past medical history | ||||||
Mode of delivery | ||||||
Normal vaginal | 68/97 (70.1%) | 28/43 (65.1%) | 0.558 | 59/77 (76.6%) | 38/54 (70.4%) | 0.422 |
Instrumental | 5/97 (5.2%) | 3/43 (7.0%) | 0.669 | 4/77 (5.2%) | 3/54 (5.6%) | 0.928 |
Caesarian | 24/97 (24.7%) | 12/43 (27.9%) | 0.693 | 14/77 (18.2%) | 13/54 (24.1%) | 0.413 |
Breast feeding months | 5.09±0.8 (n=97) | 5.72±1.13 (n=43) | 0.659 | 4.61±0.62 (n=77) | 7.43±0.81 (n=54) | 0.006 |
Admitted to neonatal unit | 14/97 (14.4%) | 3/43 (7.0%) | 0.223 | 7/77 (9.1%) | 3/54 (5.6%) | 0.457 |
Other medical problems | ||||||
Diagnosed hay fever | 75/91 (82.4%) | 33/40 (82.5%) | 0.991 | 30/51 (58.8%) | 13/36 (36.1%) | 0.039 |
Diagnosed eczema | 77/95 (81.1%) | 28/40 (70.0%) | 0.162 | 42/57 (73.7%) | 32/40 (80.0%) | 0.473 |
Diagnosed allergic rhinitis | 61/93 (65.6%) | 29/38 (76.3%) | 0.232 | 22/52 (42.3%) | 11/36 (30.6%) | 0.265 |
Diagnosed gastro-oesophageal reflux¶ | 19/94 (20.2%) | 3/40 (7.5%) | 0.081 | 8/58 (13.8%) | 11/40 (27.5%) | 0.097 |
Diagnosed vocal cord dysfunction | 2/94 (2.1%) | 1/40 (2.5%) | 0.894 | 0/59 (0.0%) | 0/40 (0.0%) | NA |
Reported food allergy+ | 39/97 (40.2%) | 14/43 (32.6%) | 0.390 | 16/76 (21.1%) | 15/54 (27.8%) | 0.376 |
Allergic sensitisation | ||||||
Positive skin prick test | 69/83 (83.1%) | 33/37 (89.2%) | 0.395 | 22/65 (33.8%) | 18/48 (37.5%) | 0.688 |
Positive specific IgE | 40/47 (85.1%) | 21/24 (87.5%) | 0.784 | 14/30 (46.7%) | 13/26 (50.0%) | 0.803 |
Atopy§ | 70/82 (85.4%) | 34/38 (89.5%) | 0.540 | 23/63 (36.5%) | 18/48 (37.5%) | 0.915 |
Data are presented as n/N (%) or mean±se, unless otherwise stated. p-values were calculated using Pearson's Chi-squared test or a Kruskall–Wallis test. BMI: body mass index; NA: not applicable. #: anthropometry z-scores generated using the 1990 British growth data [22]; ¶: gastro-oesophageal reflux was diagnosed on the basis of suggestive symptoms, pH monitoring, endoscopy or response to therapy; +: symptoms of reported food allergy represent symptoms of urticaria, angioedema, pruiritis, throat tightness, stridor, chest tightness or wheeze within 2 h of contact with food; §: atopy defined as a positive skin prick test (≥3 mm) or a positive specific IgE (≥0.35 kU·L−1); ƒ: p-values adjusted for age and sex.