Comparison of patients with good and unsatisfactory therapeutic response
| Patients without improvement in cough severity (dVAS <30 mm or LCQ <1.3 points) | Patients with decrease in cough severity (dVAS ≥30 mm and LCQ ≥1.3 points) | p-value | |
| Subjects n (%) | 98 (69.0) | 44 (31.0) | |
| Age years | 56.0 (45.0–67.0) | 61.0 (47.0–67.0) | 0.526 |
| Sex, female n (%) | 69 (70.4) | 34 (77.3) | 0.398 |
| Cough duration months | 60.0 (34.0–120.0) | 60.0 (36.0–120.0) | 0.949 |
| Serum total IgE concentration IU·mL−1 | 16.0 (7.0–45.0) | 25.0 (10.0–52.0) | 0.265 |
| BMI kg·m−2 | 26.9 (23.0–30.8) | 25.7 (22.2–31.0) | 0.241 |
| FENO ppb | 14.7 (10.9–24.6) | 18.2 (15.2–26.7) | 0.040 |
| FEV1 L | 2.5 (2.2–3.2) | 2.4 (1.8–2.7) | 0.099 |
| FEV1 % predicted | 94.0 (81.0–101.0) | 93.0 (82.0–99.0) | 0.647 |
| VC L | 3.5 (2.8–4.5) | 3.2 (2.5–4.0) | 0.234 |
| VC % predicted | 106.0 (96.0–114.0) | 101.5 (93.0–111.0) | 0.211 |
| FEV1/FVC % | 74.9 (70.0–78.6) | 76.5 (68.5–79.0) | 0.956 |
| FEV1/FVC (percentile) | 25.0 (11.0–52.0) | 38.5 (11.0–52.0) | 0.891 |
| Presence of bronchial hyperresponsiveness n (%)# | 27 (32.1) | 21 (55.3) | 0.015 |
| PC20 mg·mL−1# | 1.4 (0.3–3.7) | 1.0 (0.4–4.3) | 0.958 |
| Induced sputum eosinophil %¶ | 1.0 (0.0–2.0) | 1.0 (0.0–2.0) | 0.630 |
| Induced sputum eosinophil count >3% n (%)¶ | 73 (85.9) | 35 (87.5) | 0.806 |
| Blood eosinophil count cells·µL−1 | 141.8 (97.9–216.5) | 184.8 (118.1–278.8) | 0.026 |
| Blood eosinophils ≥300 cells·µL−1, n (%) | 90 (91.8) | 34 (77.3) | 0.016 |
| Baseline LCQ score (points) | 11.7 (9.6–14.9) | 10.1 (8.1–12.9) | 0.009 |
| Baseline cough severity in VAS mm | 45.5 (30.0–70.0) | 75.0 (57.5–84.5) | <0.001 |
| Post treatment LCQ score (points) | 12.5 (10.0–15.7) | 16.9 (14.0–19.0) | <0.001 |
| Post treatment VAS mm | 40.5 (20.0–68.0) | 15.0 (5.5–27.5) | <0.001 |
| Change in LCQ score (points) | 1.0 (−0.5–3.3) | 5.6 (3.2–7.4) | <0.001 |
| Change in cough severity VAS mm | 4.5 (−10.0–18.0) | 50.0 (40.0–68.0) | <0.001 |
| Atopy n (%) | 29 (29.6) | 14 (31.8) | 0.789 |
| Asthma or NAEB n (%) | 46 (46.9) | 28 (63.6) | 0.065 |
| UACS n (%) | 44 (44.9) | 21 (47.7) | 0.754 |
| GER n (%) | 56 (57.1) | 17 (38.6) | 0.041 |
| Baseline RCC/UCC n (%) | 5 (5.1) | 1 (1.0) | 0.899 |
Data are presented as median and interquartile range or numbers and percentages. n: number of patients; IgE: immunoglobulin E; dVAS: decrease in cough severity; BMI: body mass index; FENO: fractional exhaled nitric oxide; FEV1: forced expiratory volume in 1 s; FVC: forced vital capacity; VC: vital capacity; PC20: provocative concentration of methacholine causing a 20% fall in FEV1; LCQ: Leicester Cough Questionnaire; VAS: visual analogue scale; NAEB: non-asthmatic eosinophilic bronchitis; UACS: upper airway cough syndrome; GER: gastro-oesophageal reflux; RCC: refractory chronic cough; UCC: unexplained chronic cough. #: methacholine provocation challenge was performed in 122 (85.9%) of patients. ¶: sputum was collected in 125 (88.0%) patients.