Background Asthma is a heterogenous disease characterised by chronic airway inflammation and variable airflow obstruction. We use surrogate markers of inflammation and evidence of atopy to help aid the diagnosis and monitor disease.

The aim of this project was to explore the relationship of markers of eosinophilia to asthma symptoms in new patients presenting to difficult asthma clinics.

To date, there is very limited data linking eosinophilic inflammation and the severity of asthma symptoms.

Objective To investigate the relationship between sputum and blood eosinophilia, exhaled nitric oxide and asthma symptoms as measured using asthma control test (ACT).

Method This was a prospective cohort study. Data was collected from patients attending difficult asthma clinics fulfilling the following criteria:

New patients, a diagnosis of asthma and a complete data set from initial clinic work-up (FeNO, Blood and sputum eosinophils, ACT on the same day). Patients were excluded if they were on oral steroids at the time of presentation.

Results A total of 25 patients were included in the study. The ratio of female to male was 4:1. The mean age of the patients was 39. All patients were step 4+of the BTS asthma management. The was no correlation between any of the markers of eosinophilic inflammation and ACT scores.

Discussion The lack of robust data looking into the relationship between markers of eosinophilia and symptom control poses a question as to whether we are measuring the right outcomes. With the known adverse effects of steroids, a degree of certainty that driving down markers of eosinophilia provides benefit to the patient is crucial. Asthma is such a clinical disease with a broad spectrum of symptoms. Therefore, the patients’ subjective level of symptom control should be paramount in managing the disease and tailoring their treatment. Work is ongoing to expand across multiple sites to explore this further.