Using Exercise-testing to Explore Patient Differences in Severe Asthma

The goal of this observational pilot study is to use exercise-testing to assess patients with severe asthma who have high levels of breathlessness and compare them to other groups of patients with low levels of breathlessness. We will compare the background and overall fitness levels in all groups. This may provide new knowledge to why these patients remain breathless despite being on treatment with low levels of inflammation.The main question we aim to answer is:"How are these patients different compared to patients who respond to treatment?" We will look at reasons why patients with low levels of inflammation in their lungs are still breathless despite being on treatment.Participants will be required to take part in a 6-month study were they will firstly attend a "study visit" and a 6 month follow up.At the study visit participants will be consented and required to:Complete questionnaires on their symptomsProvide information on their backgroundUndergo a physical examinationProvide blood and urine samples for specific testing for asthma and future investigationsPerform breathing testsUndergo an exercise-test on a treadmillDuring this study, researchers will compare this group will to participants who are similar but whose symptoms respond to treatment. We will also look at other groups of asthma patients who have who have different levels of inflammation in their lungs to see if there are any differences. We predict, these patients will have a different background and features to those whose symptoms respond to treatment.

Inclusion CriteriaAll participating patients will be attending the Regional Severe Asthma Service of Belfast Trust and will be:Age ≥ 18 and ≤ 80 years at screening visitAble and willing to provide written informed consent and to comply with the study protocolSevere asthma confirmed after assessment by an asthma specialist as per GINA guidelines (1)Diagnosed with asthma at least 12 months prior to screening and on GINA Step 4/5 treatment including those who are on biologic therapyOn optimal medical management as determined by clinicianExclusion criteriaExclusion criteria will be:Any absolute contraindication to CPEST (Acute myocardial infarction (3-5 days), unstable angina uncontrolled arrhythmia causing symptoms or haemodynamic compromise, syncope, active endocarditis, acute myocarditis/pericarditis, symptomatic severe aortic stenosis, uncontrolled heart failure, suspected dissecting or leaking aortic aneurysm, uncontrolled asthma, arterial desaturation at rest on room air <85%) (15)Acute exacerbation requiring oral corticosteroids in previous 4 weeks before first visitHistory of current alcohol, drug, or chemical abuse or past abuse that would impair or risk the participant's full participation in the study, in the opinion of the investigatorTreatment with an investigational agent within 30 days of assessment (or five half-lives of the investigational agent, whichever is longer)Female participants who are pregnant or lactatingOther clinically significant medical disease or uncontrolled concomitant disease despite treatment that is likely, in the opinion of the investigator, to impact the patient's ability to participate in the study