Preselection of patients at risk for COPD by two simple screening questions

The Burden of Obstructive Lung Disease study showed that in Germany, to confirm the diagnosis of chronic obstructive lung disease (COPD) in one subject, eight people ≥ 40 years of age have to be screened. The number-needed-to-screen (NNS) increased to 18 for identifying a patient with COPD ≥ GOLD stage II. These high numbers limit the cost-effectiveness of COPD screening by population spirometry. We investigated in a primary care setting whether using two simple questions regarding smoking status and presence of cough and/or dyspnea may help to preselect patients for proper diagnosis of COPD.

A total of 1088 patients aged ≥ 40 yrs without a history of chronic lung disease, who were either current or ex-smokers and complained of cough and/or dyspnea, were examined by respiratory physicians. Spirometry was carried out to confirm COPD diagnosis and severity.

A total of 61.6% of patients were male. Mean smoking history was 31.8 pack-yrs. In 516 patients (47.4%), a diagnosis of COPD was confirmed. Among these, 379 (34.8% of total) had at least GOLD stage II COPD, while 89 (8.2% of total) had advanced disease (GOLD stages III/IV). COPD prevalence was significantly associated with age and the extent of cigarette smoke exposure.

Two questions regarding smoking status and presence of cough and/or dyspnea enabled general practitioners to select patients at risk for COPD for subsequent spirometry. This preselection reduced the NNS to 2.1 for identifying a COPD patient, and to 2.9 for identifying a patient of at least GOLD stage II.