| Characteristic | Randomized Placebo (n=37) | Randomized Azithromycin (n=38) | Open-Label Azithromycin (n=22) | P* |
|---|---|---|---|---|
| Age(years), mean(SD) | 47.4 (14.2) | 45.7 (15.5) | 45.4 (15.2) | .621/.745 |
| At asthma diagnosis | 24 (<1–59) | 24 (<1–58) | 28 (11–59) | .603/.104 |
| Diagnosis at age ≥18 years | 21 (57) | 24 (63) | 19 (86) | .641/.023 |
| Male sex | 13 (35) | 11 (29) | 12 (55) | .626/.078 |
| Smoking status | .187/.028 | |||
| Never | 13 (35) | 20 (53) | 16 (73) | |
| Former | 19 (51) | 12 (32) | 6 (27) | |
| Current | 5 (14) | 6 (16) | 0 (0) | |
| White race | 33 (89) | 36 (95) | 18 (82) | .430/.227 |
| Education, median years (range) | 15 (10–20) | 14 (12–22) | 17 (12–25) | .550/<.001 |
| ≥High school graduate | 35 (95) | 38 (100) | 21 (100) | .240/1.000 |
| Chronic sinusitis | 11 (30) | 14 (37) | 17 (77) | .626/<.001 |
| Atopy | ||||
| Allergy tested | 18 (53) | 18 (49) | 19 (86) | .814/.003 |
| Negative | 2 (11) | 1 (6) | 6 (32) | .759/.003 |
| Positive for 1–3 positive | 4 (22) | 3 (17) | 8 (42) | |
| Positive for ≥4 | 12 (67) | 14 (78) | 5 (26) | |
| Infectious asthma† | 6 (16) | 17 (46) | 13 (59) | .011/.024 |
| Exacerbations (previous 2 years), n (%) | 24 (65) | 26 (68) | 14 (64) | .809/.802 |
| Hospitalized | 0 (0) | 2 (5) | 4 (18) | .493/.023 |
| Emergency visit | 14 (38) | 19 (50) | 9 (41) | .355/1.000 |
| Steroid burst | 22 (59) | 24 (63) | 13 (59) | .815/1.000 |
| Baseline asthma severity, n (%) | ||||
| Day symptom frequency‡ | .675/.009 | |||
| Mild to moderate | 35 (95) | 34 (89) | 15 (68) | |
| Severe | 2 (5) | 4 (11) | 7 (32) | |
| Night symptom frequency‡ | 1.000/.046 | |||
| Mild to moderate | 33 (89) | 33 (87) | 15 (68) | |
| Severe | 4 (11) | 5 (13) | 7 (32) | |
| Coexisting COPD | 8 (22) | 5 (13) | 2 (9) | .375/.509 |
| Lung function, mean (SD) | ||||
| FEV1, L (n) | 18 | 19 | 7 | |
| Low§ | 2.24 (1.25) | 2.33 (1.05) | 2.48 (1.19) | .812/.688 |
| % Change‖ | 42 (47.4) | 26 (25.9) | 33 (26.8) | .214/.969 |
| PEFR, L/min (n with value) | 25 | 25 | 18 | |
| Low§ | 258 (110) | 276 (110) | 300 (105) | .566/.281 |
| % Change‖ | 62 (56) | 63 (49) | 85 (63) | .927/.140 |
| Any controller medication | 33 (89) | 25 (66) | 19 (86) | .026/.549 |
| Inhaled corticosteroid | 30 (81) | 24 (63) | 18 (82) | |
| Long-acting bronchodilator¶ | 26 (70) | 14 (37) | 15 (68) | |
| Leukotriene inhibitor | 8 (22) | 9 (24) | 6 (27) | |
| Oral prednisone | 4 (11) | 2 (5) | 1 (5) | |
| Baseline asthma measures, mean (SD)** | ||||
| Overall asthma symptoms | 1.48 (0.94) | 1.42 (0.77) | 2.06 (0.73) | .744/.005 |
| Asthma quality of life | 4.97 (1.28) | 4.98 (1.27) | 4.12 (1.29) | .988/.023 |
| Asthma control | 1.56 (1.02) | 1.75 (0.93) | 2.26 (1.35) | .424/.090 |
Values provided as n (%) unless otherwise indicated.
↵* P values comparing randomized placebo versus randomized azithromycin/randomized cohort versus open-label cohort.
↵† History showed first asthma symptoms began after an acute respiratory illness.
↵‡ Day: mild = ≥2 days/week to less than daily; moderate = ≥1 per day to less than continuous; severe = continuous. Night: mild = ≥2 per month to ≤1 per week; moderate = >1 per week to ≤1 per night; severe = >1 per night.
↵§ Before bronchodilator use or lowest spontaneous value.
↵‖ Based on data after bronchodilator use or highest spontaneous value. Some subjects had either FEV1 or PEFR values, not both.
↵¶ All subjects using a long-acting bronchodilator also were using an inhaled corticosteroid.
↵** See Methods for definitions.
COPD, chronic obstructive pulmonary disease; FEV1, forced expiratory volume in 1 second; PEFR, peak expiratory flow rate.