Table 1.
Baseline Characteristics of Adult Participants in SARP III Stratified by Longitudinal Category of Change in Lung Function
| Characteristic | Severe Decline | Mild Decline | No Change | Improvement | P Value |
|---|---|---|---|---|---|
| Baseline visit, n | 78 | 91 | 114 | 113 | — |
| Age at baseline, yr | 50.0 ± 12.7 | 47.5 ± 14.2 | 46.9 ± 14.5 | 46.9 ± 14.5 | 0.415 |
| Duration of asthma, yr | 26.3 ± 16.3 | 28.8 ± 16.7 | 28.8 ± 15.3 | 26.7 ± 14.4 | 0.538 |
| Sex | |||||
| M, n (%) | 26 (33.3) | 29 (31.9) | 41 (36) | 35 (31) | 0.869 |
| F, n (%) | 52 (66.7) | 62 (68.1) | 73 (64) | 78 (69) | |
| Race | |||||
| White, n (%) | 53 (67.9) | 59 (64.8) | 79 (69.3) | 69 (61.1) | 0.872 |
| Black, n (%) | 17 (21.%) | 24 (26.4) | 25 (21.9) | 30 (26.5) | |
| Other, n (%) | 8 (10.3) | 8 (8.8) | 10 (8.%) | 14 (12.4) | |
| Hispanic, n (%) | 4 (5.1) | 3 (3.3) | 3 (2.6) | 5 (4.4) | 0.804 |
| BMI, kg/m2 | 32.1 ± 7.7 | 32.3 ± 9.1 | 31.5 ± 7.8 | 32.8 ± 8.8 | 0.727 |
| Severe asthma at baseline, n (%) | 49 (62.8) | 43 (47.3) | 57 (50) | 61 (54) | 0.197 |
| ICS dose | |||||
| None, n (%) | 4 (5.1) | 11 (12.1) | 17 (14.9) | 15 (13.3) | 0.112 |
| Low, n (%) | 13 (16.7) | 13 (14.3) | 11 (9.6) | 17 (15) | |
| Medium, n (%) | 9 (11.5) | 22 (24.2) | 22 (19.3) | 14 (12.4) | |
| High, n (%) | 52 (66.7) | 45 (49.5) | 64 (56.1) | 67 (59.3) | |
| On maintenance OCS, n (%) | 9 (11.5) | 9 (9.9) | 9 (7.9) | 12 (10.6) | 0.845 |
| Dose of OCS, mg/d | 10 (5–15) | 10 (5–21) | 10 (5–10) | 8 (5–15) | 0.630 |
| Number of controller therapies | 3 (2–3) | 2 (2–3) | 2 (2–3) | 2 (2–3) | 0.012 |
| Baseline exacerbations in prior 12 mo | 1 (0–2); min, max: 0, 12 | 0 (0–2), min, max: 0, 9 | 0 (0–1), min, max: 0, 12 | 1 (0–2), min, max: 0, 12 | 0.012 |
| Baseline ACT score | 16.8 ± 4.3 | 17.5 ± 4.6 | 18.1 ± 4.5 | 17.2 ± 4.7 | 0.260 |
| Baseline MARS score | 22.3 ± 2.6 | 22.4 ± 2.9 | 22.3 ± 2.9 | 21.7 ± 3.7 | 0.326 |
| Baseline ASSESS score | 9.1 ± 3.7 (n = 78) | 8.3 ± 3.7 (n = 90) | 7.9 ± 3.7 (n = 114) | 8.7 ± 4.2 (n = 113) | 0.153 |
| PreBD FEV1% predicted | 75.6 ± 20.8 | 73.1 ± 17.6 | 74.5 ± 19.7 | 72.2 ± 21.0 | 0.669 |
| Maximum albuterol reversibility, postBD − preBD | 12.4 ± 7.4 | 10.2 ± 8.2 | 10.1 ± 6.7 | 11.5 ± 7.6 | 0.104 |
| PC20, mg/ml | 2.6 ± 2.7 (n = 27) | 3.1 ± 3.9 (n = 48) | 3.1 ± 3.7 (n = 68) | 3.1 ± 3.7 (n = 56) | 0.957 |
Definition of abbreviations: ACT = Asthma Control Test; ASSESS = Asthma Severity Scoring System; BMI = body mass index; ICS = inhaled corticosteroid; MARS = Medication Adherence Report Scale; max = maximum; min = minimum; OCS = oral corticosteroid; PC20 = provocative concentration of methacholine, causing a 20% fall in FEV1; postBD = post-bronchodilator value; preBD = pre-bronchodilator value; SARP III = Severe Asthma Research Program III.
Continuous data with normal distributions are presented as means and SDs, with testing conducted by ANOVA. Categorical variables are shown as the number of participants and percentage within each lung-function-change category, with significance testing conducted by using the Fisher exact test. The sample size is included for those characteristics with notable amounts of missing data for comparison with the totals in each category.