Symptom-based questionnaire for differentiating COPD and asthma.
BACKGROUND
Many patients with obstructive lung disease (OLD) carry an inaccurate diagnostic label. Symptom-based questionnaires could identify persons likely to need spirometry.


OBJECTIVE
We prospectively tested questions derived from a comprehensive literature review and an international Delphi panel to help identify chronic OLD (COPD) in persons with prior evidence of OLD.


METHODS
Subjects were recruited via random mailing to primary-care practices in Aberdeen, Scotland, and Denver, Colorado. Persons aged 40 and older reporting any prior diagnosis of OLD or any respiratory medications in the past year were enrolled. Participants answered 54 questions covering demographics and symptoms and underwent spirometry with reversibility testing. A study diagnosis of COPD was defined by fixed airway obstruction as measured by post-bronchodilator FEV(1)/FVC <0.70. We examined ability of individual questions in a multivariate framework to discriminate between persons with and without the study diagnosis of COPD.


RESULTS
597 persons completed all investigations and proceeded to analysis. The list of 54 questions yielded 52 items for analyses, which was reduced to 19 items for entry into a multivariate regression model. Nine items had significant relationships with the study diagnosis of COPD, including increased age, pack-years, worsening cough, breathing-related disability or hospitalization, worsening dyspnea, phlegm quantity, cold going to the chest, and receipt of treatment for breathing. Individual items yielded odds ratios ranging from 0.33 to 20.7. This questionnaire demonstrated a sensitivity of 72.0 and a specificity of 82.7.


CONCLUSIONS
A short, symptom-based questionnaire identifies persons more likely to have COPD among persons with prior evidence of OLD.
Tinkelman
David G
DG
National Jewish Medical and Research Center, Denver, Colo., USA.
Price
David B
DB
Nordyke
Robert J
RJ
Halbert
R J
RJ
Isonaka
Sharon
S
Nonikov
Dmitry
D
Juniper
Elizabeth F
EF
Freeman
Daryl
D
Hausen
Thomas
T
Levy
Mark L
ML
Ostrem
Anders
A
van der Molen
Thys
T
van Schayck
Constant P
CP
D000328:Adult; D000368:Aged; D001249:Asthma / Q000175:diagnosis* / Q000453:epidemiology / Q000503:physiopathology; D003120:Colorado / Q000453:epidemiology; D003937:Diagnosis, Differential; D005260:Female; D005541:Forced Expiratory Volume; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D011446:Prospective Studies; D029424:Pulmonary Disease, Chronic Obstructive / Q000175:diagnosis* / Q000453:epidemiology / Q000503:physiopathology; D012606:Scotland / Q000453:epidemiology; D013147:Spirometry; D011795:Surveys and Questionnaires