Table 1.
Demographic and clinical characteristics of the subjects studied.
| Non-Persistent Airflow Limitation n = 45 |
Persistent Airflow Limitation n = 47 |
Control n = 36 |
p-Value Non-Persistent vs. Persistent Limitation |
p-Value Non-Persistent Limitation vs. Control |
p-Value Persistent Limitation vs. Control |
|
|---|---|---|---|---|---|---|
| Demographic variables | ||||||
| Age, years | 52 (41–59) | 58 (52–65) | 55 (45–65) | 0.004 | 0.07 | 0.27 |
| Male gender, n (%) | 10 (22) | 16 (34) | 5 (14) | 0.15 | 0.5 | 0.07 |
| Body mass index, kg/m2 | 27.8 (24.8–30.8) | 26.4 (23.5–31.6) | 27.3 (23.0–27.9) | 0.53 | 0.13 | 0.95 |
| Smoking history | ||||||
| Past smoking, n (%) | 13 (29) | 15 (32) | 12 (33) | 0.93 | 0.85 | 0.92 |
| Pack-years of smoking | 0 (0–7) | 0 (0–8) | 0 (0–4) | 0.85 | 0.84 | 0.9 |
| Comorbidities | ||||||
| Atopy, n (%) | 27 (60) | 23 (49) | 6 (17) | 0.39 | 0.0002 | 0.005 |
| GERD, n (%) | 16 (36) | 22 (47) | 23 (64) | 0.38 | 0.02 | 0.19 |
| Arterial hypertension, n (%) | 18 (40) | 28 (60) | 15 (42) | 0.09 | 0.94 | 0.16 |
| Diabetes mellitus, n (%) | 6 (13) | 12 (26) | 3 (8) | 0.23 | 0.72 | 0.08 |
| Hypercholesterolemia, n (%) | 9 (20) | 16 (34) | 6 (17) | 0.2 | 0.92 | 0.13 |
| Coronary heart disease, n (%) | 2 (4) | 5 (11) | 2 (6) | 0.47 | 0.77 | 0.67 |
| Asthma-related variables | ||||||
| Asthma duration, years | 11.5 (5–19.5) | 10 (7–20) | 0.86 | |||
| Asthma severity (GINA): persistent mild, n (%) persistent moderate, n (%) persistent severe, n (%) |
8 (18) 22 (49) 15 (33) |
7 (15) 15 (32) 25 (53) |
0.14 |
|||
| Asthma treatment: Inhaled corticosteroids, n (%) Long-acting β2-agonists, n (%) Montelukast, n (%) Theophylline, n (%) Oral corticosteroids, n (%) |
45 (100) 31 (69) 9 (20) 4 (9) 8 (18) |
47 (100) 42 (89) 4 (9) 10 (21) 15 (32) |
0.17 |
|||
| Spirometry results | ||||||
| FEV1 before bronchodilator, L | 2.79 ± 0.76 | 1.79 ± 0.8 | 2.71 ± 0.75 | <0.001 | 0.65 | <0.001 |
| FEV1 before bronchodilator, % of the predicted value | 100.3 (89.5–111.1) | 66.7 (54.1–80.6) | 110.9 (106.8–114.7) | <0.001 | <0.001 | <0.001 |
| FEV1 after bronchodilator, L | 2.92 ± 0.73 | 2.07 ± 0.95 | 2.84 ± 0.79 | <0.001 | 0.66 | <0.001 |
| FEV1 after bronchodilator, % of the predicted value | 103.8 (96.4–116.5) | 79.2 (62.8–87.2) | 116 (112.1–122.3) | <0.001 | <0.001 | <0.001 |
| FEV1/VC (before bronchodilator) | 73.3 (67.8–78.18) | 59.1 (51.7–63.8) | 74.84 (73.23–78.38) | <0.001 | 0.16 | <0.001 |
| FEV1/VC (after bronchodilator) | 76.99 (73.05–81.88) | 65.4 (54.5–68.6) | 79.33 (77.25–80.38) | <0.001 | 0.25 | <0.001 |
Table 1 footnote. Categorical variables are presented as numbers (percentages), continuous variables as median and interquartile range, or mean and standard deviation, as appropriate. Abbreviations: GERD—Gastroesophageal reflux disease, GINA—Global Initiative for Asthma, FEV1—Forced expiratory volume in 1 s, VC—Vital capacity, L-liter, n—number. Statistics: Mann–Whitney U-test or unpaired t-test, as appropriate.