A combination of the IPAG questionnaire and PiKo-6® flow meter is a valuable screening tool for COPD in the primary care setting

Abstract

Aims: To investigate the validity of the International Primary Care Airways Guidelines (IPAG) questionnaire and PiKo-6® (Ferraris Respiratory Europe Ltd.) flow meter as screening tools for diagnosing chronic obstructive pulmonary disease (COPD) in the primary care setting. Methods: The first 50 patients in 25 general practice offices completed the IPAG questionnaire and underwent spirometry with the handheld PiKo-6® flow meter. The results were compared with official spirometry parameters after bronchodilation. All participants had no previous medical diagnosis of respiratory diseases. Results: Data from 1,078 out of 1,250 subjects (462 males, mean age 65.3±11.4 years) were analysed. The percentage of smokers was 48.4% (38±29 pack-years). COPD was diagnosed in 111 (10.3%) patients. In the subgroup of smokers the sensitivity and specificity for COPD diagnosis were 91% and 49%, respectively, for the IPAG questionnaire; 80% and 95% respectively for the PiKo-6® spirometer; and 72% and 97% for their combination. The negative predictive value of the questionnaire was 97%, whereas the positive predictive value of the questionnaire/ PiKo-6® combination was 82%. Using a cut-off score of 19 points for the IPAG questionnaire, we calculated the best combination of sensitivity (75%) and specificity (72%). Conclusions: The IPAG questionnaire and the hand-held PiKo-6® spirometer can be used in combination to increase the possibility of an early and accurate diagnosis of COPD in the primary care setting. © 2011 Primary Care Respiratory Society UK. All rights reserved.