Table 3.
Univariate analysis in terms of the frequency of exacerbation
| Factor | r | 95% CI | p Value |
| Age | 0.21 | −0.037 to 0.43 | 0.095 |
| BMI | −0.010 | −0.33 to 0.15 | 0.435 |
| Smoking history pack-year | −0.06 | −0.30 to 0.19 | 0.648 |
| I-SW/SW-I rate | 0.37 | 0.14 to 0.56 | 0.002 |
| Deglutition apnoea duration | 0.27 | 0.029 to 0.48 | 0.028 |
| Swallowing latency | 0.29 | 0.046 to 0.50 | 0.020 |
| FSSG score | 0.12 | −0.13 to 0.35 | 0.341 |
| CAT | 0.28 | 0.04 to 0.49 | 0.025 |
| mMRC Dyspnoea Scale score | 0.19 | −0.06 to 0.42 | 0.131 |
| FEV1 | −0.30 | −0.51 to −0.06 | 0.013 |
| %FEV1 | −0.24 | −0.45 to 0.008 | 0.057 |
| FVC | −0.21 | −0.43 to 0.035 | 0.093 |
| FEV1/FVC | −0.27 | −0.48 to −0.03 | 0.028 |
| VC | −0.32 | −0.53 to −0.09 | 0.007 |
| %VC | −0.25 | −0.47 to −0.001 | 0.049 |
| IC/TLC | −0.35 | −0.54 to −0.11 | 0.004 |
| RV/TLC | 0.23 | −0.01 to 0.45 | 0.064 |
| DLco | −0.36 | −0.55 to −0.12 | 0.003 |
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; FVC, forced vital capacity; IC, inspiratory capacity; I-SW, swallowing during inspiration; mMRC, modified Medical Research Council; r, Pearson’s correlation coefficient; RV, residual volume; SW-I, swallowing immediately followed by inspiration; TLC, total lung capacity; VC, vital capacity.