Search

Summary: Background: Current published asthma predictive tools have moderate positive likelihood ratios (+LR) but high negative likelihood ratios (−LR) based on their recommended cut‐offs, which limit their clinical usefulness. Objective: To develop a simple clinically applicable asthma prediction tool within a population‐based birth cohort. Method: Children from the Manchester Asthma and Allergy Study (MAAS) attended follow‐up at ages 3, 8 and 11 years. Data on preschool wheeze were extracted from primary‐care records. Parents completed validated respiratory questionnaires. Children were skin prick tested (SPT). Asthma at 8/11 years (school‐age) was defined as parentally reported (a) physician‐diagnosed asthma and wheeze in the previous 12 months or (b) ≥3 wheeze attacks in the previous 12 months. An asthma prediction tool (MAAS APT) was developed using logistic regression of characteristics at age 3 years to predict school‐age asthma. Results: Of 336 children with physician‐confirmed wheeze by age 3 years, 117(35%) had school‐age asthma. Logistic regression selected 5 significant risk factors which formed the basis of the MAAS APT: wheeze after exercise; wheeze causing breathlessness; cough on exertion; current eczema and SPT sensitisation(maximum score 5). A total of 281(84%) children had complete data at age 3 years and were used to test the MAAS APT. Children scoring ≥3 were at high risk of having asthma at school‐age (PPV > 75%; +LR 6.3, −LR 0.6), whereas children who had a score of 0 had very low risk(PPV 9.3%; LR 0.2). Conclusion: MAAS APT is a simple asthma prediction tool which could easily be applied in clinical and research settings. [ABSTRACT FROM AUTHOR]

Introduction: The diagnosis of asthma is often based on characteristic patterns of symptoms in the absence of an alternative explanation, resulting in over and under diagnosis. Therefore, diagnostic guidelines usually recommend including confirmation of variable airflow obstruction. Some recommend using a sequence of objective tests; however the tests used, the specific cut-off values and the specified order are yet to be validated. We aimed to determine the optimal cut-off values and series of investigations to diagnose asthma. We also explore the potential for novel tests of small airways function and biomarkers, which could be incorporated into future diagnostic pathways., Methods and Analysis: The Rapid Access Diagnostics for Asthma study is an observational study of 300 symptomatic patients with 'clinician-suspected asthma' and healthy controls (aged ≥3 to <70 years), recruited from primary and secondary care in Greater Manchester, UK. Symptomatic participants will undergo four core visits and one optional visit. Participants will complete two baseline visits and undergo a series of established (spirometry, bronchodilator reversibility, exhaled nitric oxide, home peak flow monitoring and bronchial challenge testing) and novel tests. Following visit 2, participants will receive monitored medium-dose inhaled corticosteroid therapy for 6-8 weeks, after which they will return for repeat testing. Patients will be diagnosed with asthma by 'expert panel' opinion (minimum two respiratory specialists) on review of all data (excluding novel tests) pre and post treatment. Healthy controls will attend two visits to establish reference intervals and calculate repeatability coefficients for novel tests where there is a lack of evidence on what threshold constitutes a 'normal' set of values. The primary end point is to determine the optimum diagnostic pathway for diagnosing asthma., Ethics and Dissemination: The study was approved by Greater Manchester East Research Ethics Committee (18/NW/0777). All participants or parents/guardians are required to provide written informed consent and children to provide written assent. The results will be published in peer-review journals and disseminated widely at conferences and with the help of Asthma and Lung UK (www.asthmaandlung.org.uk)., Trial Registration Number: ISRCTN11676160., Competing Interests: Competing interests: CM has received grants from NIHR, Asthma UK, Innovate UK, Moulton Charitable Foundation, GSK and MRC; travel grants from Sanofi and lecture fees from Novartis, GSK and Sanofi. AngS has received grants from NIHR, Asthma UK, Innovate UK, Moulton Charitable Foundation, GSK and MRC. SF reports personal fees from AstraZeneca, Chiesi, GlaxoSmithKline, Novartis and Teva and grants and personal fees from Boehringer Ingelheim. All other authors declare no competing interests., (© Author(s) (or their employer(s)) 2024. Re-use permitted under CC BY. Published by BMJ.)