Abstract
Introduction: Increased cough is common in chronic obstructive pulmonary disease exacerbations (ECOPDs). We hypothesised that cough reflex sensitivity (CRS) is increased during ECOPD, and that CRS is associated with future ECOPD risk.
Methods: Patients hospitalised with ECOPD underwent inhaled capsaicin challenges to determine threshold concentrations required to elicit 5 coughs (C5) during admission (TE) and after a 6-week recovery period (TR). Spirometry, cough severity visual analogue scale (VAS) rating, and the COPD Assessment Test (CAT) were completed. In the following 12 months, the number of moderate and severe ECOPDs were recorded (requiring medication change and/or hospital admission, separated by ≥14 days) (Seemungal et al 2000).
Results: 16 patients were recruited: mean (SD) age 67 (6.6) years, 9 (56%) female, FEV1 34.6 (10.1) % predicted. C5 was significantly lower at TE than at TR; geometric mean (SD) 1.64 (3.84) vs. 8.94 (6.50) μmol⋅L-1; mean (95% CI) doubling dose difference in C5: 2.46 (0.93-3.57), p<0.01. Mean (SD) 12-month ECOPD count was 3 (1). There was an association between the increase in C5 between TE and TR and the 12-month ECOPD count (ρ=-0.68, p<0.01). ECOPD count was not associated with C5 at TE (ρ=-0.08, p=0.76) or at TR (ρ=0.18, p=0.51), change in FEV1%pred (r=-0.08, p=0.78), change in CAT scores (r=-0.40, p=0.14) nor change in cough severity VAS (r=0.30, p=0.28).
Discussion: Cough reflex sensitivity was heightened during ECOPD, and the change in C5 at 6 weeks was associated with exacerbation frequency in the following 12 months. These novel observations require further study.
Footnotes
Cite this article as: European Respiratory Journal 2019; 54: Suppl. 63, PA5221.
This is an ERS International Congress abstract. No full-text version is available. Further material to accompany this abstract may be available at www.ers-education.org (ERS member access only).
- Copyright ©the authors 2019