NICE asthma guidelines: time to re-evaluate the diagnostic value of exercise challenge testing?

Abstract

<b>Background:</b> Exercise is one of the most common symptom triggers in individuals with asthma and dyspnoea on exertion is a prominent characteristic of the disease. Despite this, current National Institute for Health and Care Excellence (NICE) guidelines currently oppose the use of exercise challenge testing to diagnose asthma. <b>Aims:</b> To evaluate the exercise challenge testing protocols in studies underpinning NICE guidelines. <b>Method:</b> Five studies were examined independently by two reviewers and evaluated against the exercise challenge testing criteria specified in the ERS Technical Standard on Indirect Bronchial Challenge Testing (Hallstrand et al., Eur Resp J 2018; 52:1801033): (i) medication restrictions, (ii) exercise intensity, (iii) exercise duration, (iv) environmental conditions, (v) post-challenge spirometry, (vi) diagnostic threshold. <b>Results:</b> None of the studies adhered to all criteria. Specifically, none of the studies adhered to all medication restrictions, n = 4 failed to adhere to appropriate environmental conditions, or diagnostic thresholds, n = 3 studies failed to conduct spirometry at the appropriate post challenge timepoints, and n = 2 studies failed to adhere to either the recommended exercise testing intensity or duration. <b>Conclusion:</b> Our findings confirm that NICE asthma guidelines are based on studies that violate current exercise challenge testing recommendations. Future research is therefore required to re-evaluate the diagnostic value of exercise challenge testing to detect asthma when conducted in accordance with up-to-date international guidance.