Exacerbation-like respiratory symptoms in individuals without chronic obstructive pulmonary disease: results from a population-based study
- W C Tan1,
- J Bourbeau2,
- P Hernandez3,
- K R Chapman4,
- R Cowie5,
- J M FitzGerald6,
- D D Marciniuk7,
- F Maltais8,
- A S Buist9,
- D E O'Donnell10,
- D D Sin1,
- S D Aaron11,
- for the CanCOLD Collaborative Research Group
- 1UBC James Hogg Research Center, Providence Heart + Lung Institute, St Paul's Hospital, University of British Columbia, Vancouver, British Columbia, Canada
- 2Respiratory Epidemiology and Clinical Research Unit, Montreal Chest Institute, McGill University, Montréal, Quebec, Canada
- 3Respirology Division, Department of Medicine, QEII Health Sciences Centre, Dalhousie University, Halifax, Nova Scotia, Canada
- 4Asthma & Airway Centre, University Health Network and University of Toronto, Toronto, Ontario, Canada
- 5Departments of Medicine and Community Health Sciences, University of Calgary, Calgary, Alberta, Canada
- 6University of British Columbia, Institute for Heart and Lung Health, Vancouver, British Columbia, Canada
- 7Division of Respirology, Critical Care and Sleep Medicine, and Airway research Group, University of Saskatchewan, Saskatoon, Saskatchewan, Canada
- 8Centre de Pneumologie, Institute Universitaire de Cardiologie et de Pneumologie de Québec, Quebec, Canada
- 9Oregon Health and Science University, Portland, Oregon, USA
- 10Division of Respiratory & Critical Care Medicine, Queen's University, Kingston, Ontario, Canada
- 11Ottawa Hospital Research Institute, University of Ottawa, Ottawa, Ontario, Canada
- Correspondence to Dr Wan C Tan, UBC James Hogg Research Centre, Providence Heart + Lung Institute, University of British Columbia, St Paul's Hospital, Rm 166, 1081 Burrard Street, Vancouver, British Columbia, Canada V6Z 1Y6;
- Received 20 December 2013
- Revised 3 March 2014
- Accepted 12 March 2014
- Published Online First 4 April 2014
Rationale Exacerbations of COPD are defined clinically by worsening of chronic respiratory symptoms. Chronic respiratory symptoms are common in the general population. There are no data on the frequency of exacerbation-like events in individuals without spirometric evidence of COPD.
Aims To determine the occurrence of ‘exacerbation-like’ events in individuals without airflow limitation, their associated risk factors, healthcare utilisation and social impacts.
Method We analysed the cross-sectional data from 5176 people aged 40 years and older who participated in a multisite, population-based study on lung health. The study cohort was stratified into spirometrically defined COPD (post-bronchodilator FEV1/FVC < 0.7) and non-COPD (post bronchodilator FEV1/FVC ≥ 0.7 and without self-reported doctor diagnosis of airway diseases) subgroups and then into those with and without respiratory ‘exacerbation-like’ events in the past year.
Results Individuals without COPD had half the frequency of ‘exacerbation-like’ events compared with those with COPD. In the non-COPD group, the independent associations with ‘exacerbations’ included female gender, presence of wheezing, the use of respiratory medications and self-perceived poor health. In the non-COPD group, those with exacerbations were more likely than those without exacerbations to have poorer health-related quality of life (12-item Short-Form Health Survey), miss social activities (58.5% vs 18.8%), miss work for income (41.5% vs 17.3%) and miss housework (55.6% vs 16.5%), p<0.01 to <0.0001.
Conclusions Events similar to exacerbations of COPD can occur in individuals without COPD or asthma and are associated with significant health and socioeconomic outcomes. They increase the respiratory burden in the community and may contribute to the false-positive diagnosis of asthma or COPD.
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