Upper airway symptoms and Small Airways Disease in Chronic Obstructive Pulmonary Disease, COPD.

Background: Small Airways Disease (SAD) is a recognised part of the pathology in Chronic Obstructive Pulmonary Disease (COPD) and contributes to the symptom burden in the disease. Upper airway symptoms in COPD is an emerging field of study, and in this study, we sought to examine the co-existence of SAD and upper airways symptoms in a cohort of COPD patients METHODS: We investigated a cohort of patients with COPD for the presence of SAD with three different modalities. We performed High-Resolution CT (HRCT) with Parametric Response Mapping (PRM) analysis and recorded distribution of emphysema (PRM) and functional Small Airways Disease (PRM). We measured central and peripheral lung resistance using Impulse Oscillometry (IOS) and recorded R5Hz, R20Hz, R5-R20Hz, X5, Fres and Ax. Static lung function parameters were obtained using Body Plethysmography. Data on upper and lower airway symptoms were evaluated using the Upper Airway subdomain of the 22 items Sino Nasal Outcome Test (SNOT22) and the COPD Assessment Test (CAT), respectively.

Findings: We recruited a total of 112 patients. (female sex: 58%, Age 68 (±8) years, FEV1%predicted: 53% (±16%), GOLD stage: A: 23%, B: 55%, C:1% D: 21%). Forty-five (40%) were classified as having high upper airway symptoms (UAS), defined as SNOT22 ≥6. Eighty-seven per cent showed signs of SAD using IOS (R5-R20Hz > 0.07 kPa/L/s). No significant differences were found between UAS groups in IOS, PRM or Body Plethysmography parameters.

Conclusion: In patients with COPD, the prevalence of small airways disease was very high, but no association between upper airway symptoms and small airways disease was demonstrated.