Abstract
Introduction/Aim. Diagnosis of COPD in Australian primary care is challenging due to underuse of spirometry, the ‘gold standard’ for diagnosis. Case finding using validated symptom and health status questionnaires and handheld devices in at risk populations may improve COPD diagnosis. The aim of this study was to determine the best combination of tools to optimise COPD diagnosis in primary care.
Method. We examined 394 participants from RADICALS, a community‐based trial investigating an interdisciplinary intervention in current or ex‐smokers, including those with an existing diagnosis of COPD. We measured FEV1 and FEV6 using a handheld device (COPD‐6®), responses to COPD assessment test (CAT), modified Medical Research Council (mMRC) dyspnoea scale, smoking and St George's Respiratory Questionnaire (SGRQ) to assess predictive performance for post‐bronchodilator spirometry‐confirmed diagnosis of COPD. To determine the diagnostic accuracy of FEV1 and FEV6 and the questionnaires, area under the receiver operating characteristic curve (AUROC) was calculated. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and positive likelihood ratio, were calculated for each test.
Results. COPD was confirmed using post‐bronchodilator spirometry in 272 participants (FEV1/FVC < 0.7 plus clinical correlation). FEV1/FEV6 alone showed significant association (P < 0.0001) for COPD with good predictive accuracy (AUROC: 0.766). Whereas SGRQ (AUROC 0.635), CAT (0.619) and mMRC (0.608) showed poor predictive performance with no significant associations on multivariable logistic regression. These instruments did not improve predictive performance when combined with FEV1 /FEV6 (AUROC: 0.73). FEV1/FEV6 <0.72 using COPD‐6® had high sensitivity (80%) and PPV (82%), moderate specificity (60%) and NPV (57%); the positive likelihood ratio was 1.98.
Conclusion. Handheld mini‐spirometers with a cut‐off of FEV1/FEV6 < 0.72 is ideal for case finding of COPD in the primary healthcare setting. Use of CAT, SGRQ and mMRC, alone or in combination with FEV1/FEV6 measurements, does not assist in case finding or diagnosis of COPD.
Key Words: COPD, Spirometry
Nomination for New Investigator Award:
Grant Support: NHMRC Partnership Grant (APP1076255); Boehringer‐Ingelheim
Method. We examined 394 participants from RADICALS, a community‐based trial investigating an interdisciplinary intervention in current or ex‐smokers, including those with an existing diagnosis of COPD. We measured FEV1 and FEV6 using a handheld device (COPD‐6®), responses to COPD assessment test (CAT), modified Medical Research Council (mMRC) dyspnoea scale, smoking and St George's Respiratory Questionnaire (SGRQ) to assess predictive performance for post‐bronchodilator spirometry‐confirmed diagnosis of COPD. To determine the diagnostic accuracy of FEV1 and FEV6 and the questionnaires, area under the receiver operating characteristic curve (AUROC) was calculated. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and positive likelihood ratio, were calculated for each test.
Results. COPD was confirmed using post‐bronchodilator spirometry in 272 participants (FEV1/FVC < 0.7 plus clinical correlation). FEV1/FEV6 alone showed significant association (P < 0.0001) for COPD with good predictive accuracy (AUROC: 0.766). Whereas SGRQ (AUROC 0.635), CAT (0.619) and mMRC (0.608) showed poor predictive performance with no significant associations on multivariable logistic regression. These instruments did not improve predictive performance when combined with FEV1 /FEV6 (AUROC: 0.73). FEV1/FEV6 <0.72 using COPD‐6® had high sensitivity (80%) and PPV (82%), moderate specificity (60%) and NPV (57%); the positive likelihood ratio was 1.98.
Conclusion. Handheld mini‐spirometers with a cut‐off of FEV1/FEV6 < 0.72 is ideal for case finding of COPD in the primary healthcare setting. Use of CAT, SGRQ and mMRC, alone or in combination with FEV1/FEV6 measurements, does not assist in case finding or diagnosis of COPD.
Key Words: COPD, Spirometry
Nomination for New Investigator Award:
Grant Support: NHMRC Partnership Grant (APP1076255); Boehringer‐Ingelheim
| Original language | English |
|---|---|
| Article number | TO 052 |
| Pages (from-to) | 47 |
| Number of pages | 1 |
| Journal | Respirology |
| Volume | 25 |
| Issue number | S1 |
| DOIs | |
| Publication status | Published - Jun 2020 |