Dysfunctional Breathing Impacts Symptom Burden In Chronic Obstructive Pulmonary Disease (Copd)

Background: Involuntary adaptations of breathing patterns to counter dyspnea may lead to dysfunctional breathing (DB). Preliminary studies showed that DB may be common in COPD, and is negatively associated with quality of life. However, it is unknown how DB relates to COPD severity in terms of health-related quality of life, lung function and comorbidities of anxiety and depression. Methods: COPD patients (n=264), without asthma comorbidity, from the BREATHE study were studied cross-sectionally. Patients completed the Nijmegen questionnaire for DB (NQ; 16-questions, max. score 64), COPD assessment test (CAT), Hospital anxiety and depression questionnaire (HADS), spirometry and body plethysmography. Results: 17.4% of patients had a positive NQ (cut-off >23). Compared to those with a negative NQ (≤23), these patients were younger (64±9.0 vs 68±8.5 years; p<0.01), had a higher CAT score (21.0±5.4 vs 13.4±6.7; p<0.001), higher HADS-anxiety (8.2±3.4 vs 3.6±2.9) and depression scores (4.8±3.3 vs 2.6±2.5; both p<0.001), but similar gender distribution, FEV1 (55 vs 56%pred), RV/TLC (57.9 vs 60.5%) and RV (173 vs 189%pred). Multivariate analysis showed that CAT and HADS-anxiety were independently associated with presence of DB (both p<0.001). Furthermore, multivariate analysis showed that presence of DB was independently associated with CAT scores (p<0.001). Conclusion: Abnormal breathing behaviors seem to impact symptom burden in COPD, independent of lung function. However, the NQ has not been validated in COPD, and it is unclear if strategies to reduce abnormal breathing behaviors may have benefits for health-related quality of life in COPD.