Patient characteristics stratified by patients who did and did not experience exacerbation during the 2-year observation period
| Exacerbation during the 2-year observation period | |||
| Variable | Patients with exacerbation | Patients without exacerbation | p Value |
| Total number of patients | 25 | 40 | |
| Age, years | 73.2±9.1 (46–88) | 71.1±7.92 (46–89) | 0.321 |
| Height, cm | 163.1±7.3 (145.3–175.9) | 165.6±5.5 (149.8–178) | 0.118 |
| Weight, kg | 59.0±11.0 (41.5–88) | 61.4±8.2 (41.9–85) | 0.332 |
| BMI, kg/m2 | 22.1±3.6 (16–31.6) | 22.4±2.5 (16.3–27.1) | 0.782 |
| Smoking status, former/current | 25/0 | 35/5 | 0.147 |
| Smoking history, pack-years | 57.2±29.8 (24.8–153) | 67.0±33.7 (18–184) | 0.239 |
| FSSG score | 7.3±5.8 (0–19) | 5.3±6.1 (0–36) | 0.186 |
| GER symptoms (FSSG ≥8) | 12/25 | 8/40 | 0.017 |
| CAT | 13.4±7.2 (1–28) | 9.9±6.6 (1–27) | 0.047 |
| mMRC Dyspnoea Scale, 0/1/2/3/4 | 4/15/5/1/0 | 17/13/8/1/0 | 0.106 |
| GOLD stage, I/II/III/IV | 2/14/5/4 | 7/21/10/2 | 0.358 |
| FEV1, L | 1.41±0.61 (0.62–2.82) | 1.75±0.61 (0.66–2.91) | 0.028 |
| FEV1, %predicted | 53.7±19.9 (17.7–96.9) | 62.1±19.2 (22.7–92.9) | 0.095 |
| FVC, L | 3.03±0.7 (1.8–4.3)±0.7(1.8–4.3) | 3.3±0.8(1.8–5.0) | 0.147 |
| FEV1/FVC, % | 45.5±13.0 (23.3–65.9) | 52.6±13.2 (0.3–100) | 0.037 |
| VC, L | 3.2±0.7 (2.0–4.5) | 3.7±0.7 (2.5–5.0) | 0.011 |
| VC, % predicted | 95.2±17.5 (63–124.1) | 102.4±14.53 (73.3–131.7) | 0.083 |
| IC/TLC, % | 35.8±7.1 (24.2–47.1) | 39.1±6.1 (26.1–52.9) | 0.051 |
| RV/TLC, % | 42.0±7.7 (27.1–54.8) | 40.2±7.43 (28.9–67.2) | 0.373 |
| DLco, mL/min/mm Hg | 11.5±4.4 (6.7–21.8) | 14.4±5.7 (3.6–28.3) | 0.032 |
| I-SW/SW-I rate | 32.5±31.1 (0–87.5) | 14.6±18.7 (0–75) | 0.005 |
| Swallowing latency, s | 519.6±584.2 (−99.9–2031.5) | 276.8±362.8 (−141.9–1641.5) | 0.042 |
| Apnoea duration, ms | 1.6±0.8 (0.5–3.1) | 1.3±0.6 (0.4–2.6) | 0.074 |
The continuous variables are presented as the mean±SD (range).
BMI, body mass index; CAT, Chronic Obstructive Pulmonary Disease Assessment Test; DLco, diffusing capacity of carbon monoxide; FEV1, forced expiratory volume in 1 s; FSSG, frequency scale for symptoms of gastro-oesophageal reflux disease; GER, gastro-oesophageal reflux; FVC, forced vital capacity; GOLD, Global Initiative for Chronic Obstructive Lung Disease; IC, inspiratory capacity; I-SW, swallowing during inspiration; mMRC, modified Medical Research Council; RV, residual volume; SW-I, swallowing immediately followed by inspiration; TLC, total lung capacity; VC, vital capacity.