Abstract
UK NICE guidance for asthma diagnosis specify BDR, a simple and widely available low cost test, should only be tested in those with obstructed spirometry (OS), defined as FEV1/FVC ratio < 70% or < LLN if available. Those without BDR proceed to other tests such as FeNO, peak flow diary, bronchial challenge. We investigated how common BDR (defined as ≥12% increase in FEV1 following 400 mcg salbutamol) was in adults with symptoms of asthma, with and without OS.
Method: Adults with asthma symptoms underwent a thorough diagnostic evaluation as part of the RADicA study including history, examination, lung function (spirometry, BDR, FeNO, PEFv and challenge testing) then were treated with inhaled corticosteroids for 8 weeks, followed by repeat testing. Results were evaluated by a panel of respiratory experts to reach a diagnosis of asthma or not; those with insufficient evidence were excluded. We compared BDR in those with and without OS.
Results: 60 adults mean (SD) age 34.8 (12.2) years, 36.9% male, completed the study. Following completion of treatment, 36 were diagnosed with asthma and 24 did not have asthma. Only 13 (22%) had OS (FEV1/FVC ratio < LLN); all were subsequently diagnosed with asthma. 16 (26.7%) had BDR; all were diagnosed with asthma. Of the 13 with OS, 11 (85%) also had BDR. Of the 47 without OS, 5 (11%) also had BDR. Of the 36 diagnosed with asthma, 18 (50%) had neither OS nor BDR.
Conclusion: Using OS as a criterion for BDR assessment missed >10% of adults who went on to be diagnosed with asthma after further work-up. Amongst adults with symptoms in keeping with asthma, measurement of BDR should be considered even in those without OS.
Footnotes
Cite this article as: European Respiratory Journal 2021; 58: Suppl. 65, PA3626.
This abstract was presented at the 2021 ERS International Congress, in session “Prediction of exacerbations in patients with COPD”.
This is an ERS International Congress abstract. No full-text version is available. Further material to accompany this abstract may be available at www.ers-education.org (ERS member access only).
- Copyright ©the authors 2021