Symptom-Based Questionnaire for Differentiating COPD and Asthma

Abstract

Background: Many patients with obstructive lung disease (OLD) carry an inaccurate diagnostic label. Symptom-based questionnaires could identify persons likely to need spirometry. Objectives: 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 FEV₁/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.

Difficulties in differential diagnosis of COPD and asthma in primary care

“…This study assessed the usefulness of the two questionnaires as complementary method of diagnosis; in fact, neither questionnaire was designed as a diagnostic methods but rather to facilitate the differentiation of asthma and COPD once a chronic obstructive airway disease had been diagnosed. 11,17 In their study, Beeh and colleagues 17 concluded that, by means of their questionnaire, most patients with a suspected or established diagnosis of obstructive airway diseases could be classified in asthmatic or COPD groups. Despite the slight improvement achieved with the addition of spirometry results, these authors recognised that spirometry should be mandatory to support the initial diagnosis of an obstructive airway disease and to guide therapy.…”

“…Despite the slight improvement achieved with the addition of spirometry results, these authors recognised that spirometry should be mandatory to support the initial diagnosis of an obstructive airway disease and to guide therapy. On the other hand, Tinkelman and colleagues 11 found their questionnaire to be useful for patients suspected of having obstructive lung disease or those receiving respiratory medications in the absence of a specific diagnosis, although they did recognise the importance of a more efficient use of spirometry and a enhanced diagnostic accuracy to improve the overall management. On observing the poor concordance shown in the current study it was concluded that the questionnaires are of little help in addition to clinical assessment and spirometry with bronchodilator test for the differential diagnosis between asthma and COPD.…”

“…Used in conjunction with spirometry, these tools may enhance the diagnostic accuracy of obstructive lung disease. 2,11 Differentiating between asthma and COPD is essential for determining appropriate drug therapy. For the treatment of asthma, inhaled corticosteroids (ICs) are the most effective controller medications currently available.…”

The International Primary Care Respiratory Group (IPCRG) Research Needs Statement 2010

“…35 Validated questionnaires have been developed to support the diagnosis of COPD. [159][160][161] Practical experience with these tools is limited and it is not yet clear how such questionnaires can best be used in clinical practice -e.g. to identify patients for spirometry, or to replace spirometry in low income countries where spirometry is not available.…”

International Primary Care Respiratory Group (IPCRG) Guidelines: Integrating diagnostic guidelines for managing chronic respiratory diseases in primary care

“…Using a similar validation process, this tool has been demonstrated to support diagnosis in a primary care setting [45].…”