Table 1.
Adult Nonsevere (n = 213) | Adult Severe (n = 313) | Pediatric Nonsevere (n = 77) | Pediatric Severe (n = 111) | |
---|---|---|---|---|
Age at baseline visit, yr | 44.5 ± 14.6* | 49.7 ± 12.8 | 11.6 ± 2.9 | 11.5 ± 2.8 |
Age at diagnosis of asthma, yr | 19.1 ± 15.3 | 20.0 ± 16.5 | 3.2 ± 2.8 | 3.0 ± 2.7 |
Age at onset of symptoms, yr | 16.3 ± 13.9 | 17.4 ± 16.0 | 2.3 ± 2.4 | 2.4 ± 2.6 |
Years since diagnosis of asthma | 25.4 ± 15.6* | 29.7 ± 15.6 | 8.4 ± 3.8 | 8.4 ± 3.4 |
Years since onset of asthma symptoms | 28.1 ± 15.9* | 32.3 ± 15.7 | 9.3 ± 3.4 | 9.1 ± 3.2 |
Body mass index, kg/m2 (percentile for pediatric groups) | 31.0 ± 7.9* | 33.5 ± 8.5 | 73.7 ± 26.5 | 77.1 ± 26.8 |
Pre-TA, pre-BD FEV1% predicted from visit 2 | 81.0 ± 16.4* | 66.7 ± 19.7 | 93.1 ± 14.4* | 86.3 ± 16.3 |
Pre-TA, max FEV1% predicted | 92.2 ± 15.5* | 77.9 ± 19.7 | 105.6 ± 13.4 | 103.4 ± 17.5 |
Pre-BD FEV1/FVC | 0.72 ± 0.09* | 0.66 ± 0.11 | 0.78 ± 0.08 | 0.75 ± 0.10 |
Pre-BD FEV1/FVC% predicted | 87.9 ± 10.4* | 81.7 ± 13.9 | 88.4 ± 9.6† | 85.3 ± 11.1 |
Maximum FEV1 albuterol response (absolute change in % predicted) | 10.5 ± 7.8† | 11.9 ± 7.9 | 12.4 ± 7.8† | 16.2 ± 11.0 |
Methacholine PC20, median (IQR) | 1.6 (0.5–4.2) | 1.4 (0.4–4.1) | 1.4 (0.6–4.4) | 0.9 (0.4–4.9) |
ACQ-6 | 1.1 ± 0.9* | 1.9 ± 1.1 | 0.9 ± 0.8* | 1.3 ± 0.9 |
ACT/CACT(6–11) score | 19.2 ± 4.0* | 15.3 ± 4.8 | 19.8 ± 3.5* | 17.0 ± 4.4 |
FeNO, ppb, median (IQR) | 24.0 (16.0–43.0)† | 21.0 (13.0–37.0) | 28.0 (12.0–49.0) | 23.0 (12.0–46.0) |
Sputum eosinophils, %, median (IQR) | 0.7 (0.0–2.0) | 0.8 (0.2–4.3) | 1.1 (0.2–4.2) | 1.6 (0.3–10.2) |
Blood eosinophils, cells/μl, median (IQR) | 189 (111–320)† | 228 (134–399) | 359 (208–575) | 324 (162–514) |
IgE test result, IU/ml, median (IQR) | 141 (46–374) | 163 (45–384) | 490 (151–834) | 465 (164–1,207) |
Number of positive specific IgEs (of 15 tests) | 4.8 ± 3.8* | 4.1 ± 4.1 | 6.9 ± 4.6 | 7.0 ± 4.6 |
TA response: pre-BD FEV1% predicted | 2.3 ± 7.1 | 3.4 ± 10.1 | 1.3 ± 12.5 | 2.4 ± 13.6 |
At least one positive specific IgE, n (%) | 173 (82) | 234 (75.2) | 67 (89.3) | 104 (94.5) |
Race/ethnicity, n (%) | ||||
Male sex | 71 (33.3) | 103 (32.9) | 50 (64.9) | 67 (60.4) |
White race | 142 (66.7) | 194 (62) | 33 (42.9) | 39 (35.1) |
African American race | 47 (22.1) | 85 (27.2) | 32 (41.6) | 49 (44.1) |
Other race | 24 (11.3) | 34 (10.9) | 12 (15.6) | 23 (20.7) |
Hispanic ethnicity | 9 (4.2) | 10 (3.2) | 11 (14.3) | 17 (15.3) |
Medication use in the past 3 mo, n (%) | ||||
Inhaled corticosteroids | 161 (75.6)* | 310 (99) | 65 (84.4)* | 111 (100) |
Long-acting β-agonist | 108 (50.7)* | 300 (95.8) | 32 (41.6)* | 98 (88.3) |
Long-acting anticholinergic | 3 (1.4)* | 48 (15.3) | 0 (0)† | 9 (8.1) |
Leukotriene antagonists | 51 (23.9)* | 135 (43.1) | 29 (37.7)* | 84 (75.7) |
Short-acting anticholinergic | 8 (3.8)* | 51 (16.3) | 1 (1.3)† | 11 (9.9) |
Short-acting β-agonist | 183 (85.9)* | 294 (93.9) | 68 (88.3) | 105 (94.6) |
Oral or systemic corticosteroids | 4 (1.9)* | 85 (27.2) | 1 (1.3)† | 11 (9.9) |
>2 steroid courses in the past year | 28 (13.1)* | 164 (52.4) | 18 (23.4)* | 65 (58.6) |
≥3 mo with oral corticosteroid use in the past year | 0 (0)* | 70 (22.4) | 1 (1.3)† | 11 (9.9) |
Biologics | 5 (2.3)* | 34 (10.9) | 1 (1.3) | 7 (6.3) |
Eczema | 57 (26.8) | 96 (30.7) | 44 (57.1) | 64 (57.7) |
ED visit for breathing problems in the past 12 mo | 24 (11.3)* | 101 (32.3) | 26 (33.8)* | 75 (67.6) |
Hospitalized for asthma in the past year | 6 (2.8)* | 49 (15.7) | 9 (11.7)* | 41 (36.9) |
Daily oral corticosteroids (current) | 1 (0.5)* | 70 (22.4) | 1 (1.3)* | 15 (13.5) |
Environmental smoke exposure, n (%) | ||||
Any | 25 (11.7) | 41 (13.1) | 10 (13.2) | 16 (14.4) |
Home | 14 (6.6) | 24 (7.7) | 10 (13.2) | 12 (10.8) |
Work | 6 (2.8) | 16 (5.1) | 0 (0) | 0 (0) |
Other | 9 (4.2) | 9 (2.9) | 1 (1.3) | 5 (4.5) |
Definition of abbreviations: ACQ = Asthma Control Questionnaire; ACT = Asthma Control Test; BD = bronchodilator; CACT = Childhood Asthma Control Test; ED = emergency department; FeNO = fractional exhaled nitric oxide; IQR = interquartile range; IU = international units; SARP = Severe Asthma Research Program; PC20 = provocative concentration (of methacholine in this case) that causes a 20% fall in FEV1; TA = triamcinolone acetonide.
Data are mean ± SD unless otherwise indicated.
P < 0.01; P values refer to comparison of severity by age group.
P < 0.05; P values refer to comparison of severity by age group.