Inclusion criteria | Exclusion criteria | |
---|---|---|
COPD Group | Control Group | All Groups |
Former smoker | Former smoker | Active smoking |
≥10 pack year smoking history, quit at least 3 months prior to enrollment | ≥10 pack year smoking history, quit at least 3 months prior to enrollment | Any significant pulmonary disease other than COPD which would limit the interpretability of the pulmonary function measures |
Age 40-85 | Age 40-85 | |
Moderate or severe COPD: | Spirometry without evidence of airflow obstruction | COPD exacerbationa in the prior six weeks |
FEV1/FVC below the lower limit of normal and FEV1 < 70 % predicted for age and height | No evidence of emphysema on CT imaging, if previously obtained | Currently taking ≥10 mg a day of prednisone or equivalent systemic corticosteroid |
Inability to perform exhaled breath condensate, spirometry, or complete respiratory symptom questionnaire | ||
Pregnant or intending to become pregnant |