Validation of probable COPD as proposed by the Lancet Commission at a smoking cessation clinic

The recently published recommendations of the Lancet Commission, the presence of respiratory symptoms or exacerbation in risky people, and the COPD assessment test (CAT) score ≥10 points could be defined as possible COPD without using computed tomography and spirometry, particularly in low-income countries. We aimed to validate this recommendation by spirometry in patients applying to our smoking cessation clinic.

Subjects aged ≥40 years with a smoking history of ≥15 pack-years were included in the study. Individuals with known chronic lung diseases, except childhood asthma, were excluded. All participants completed a detailed case report form, including the CAT questionnaire, and underwent spirometry testing.

A total of 224 participants, with a mean age of 53.2 ± 8.7 years of which 49.6 % were female, were enrolled in the study. According to the Lancet Commission's definition, 90 participants were identified as having probable COPD. Among these individuals, 21 (23.3 %) were also diagnosed with COPD based on the pre-bronchodilator FEV1/FVC ratio. In contrast, out of the 134 subjects, who did not meet the criteria for probable COPD, 12 (9 %) were diagnosed with COPD (P = 0.003).

This study is the first pilot study to validate the probable COPD definition recommended by the Lancet Commission using spirometry. Approximately 25 % of at-risk patients identified as having probable COPD were diagnosed with COPD based on the pre-bronchodilator FEV1/FVC ratio. Future studies are needed to assess the cost-effectiveness of the diagnostic approach outlined in the algorithm proposed by the Lancet Commission.