Assessment of the frequency of allergic asthma to birch and grass pollen using ALYATEC patients database

<bold>Background:</bold> In previous studies it has been published that 20% of grass allergic and 30% of birch allergic patients have asthma. ALYATEC is a clinical trial center which runs an Environmental Exposure Chamber (EEC) and collected medical information from more than 2000 allergic patients. <bold>Objective:</bold> To assess the frequency of asthma symptoms in birch and grass pollen allergic patients recorded in ALYATEC database. <bold>Method:</bold> In January 2024, 2079 allergic patients were included in ALYATEC database following a medical evaluation performed on site. In particular, skin prick tests for common aeroallergens and medical history were obtained for each patient. Patients gave their consent to be included in the this GDRP-compliant database. <bold>Results:</bold> The mean age was 35.3 years old [5;73], 60% were women. 90% of patients lived in Strasbourg area 71% had an asthma, 99% a rhinitis, 90% a conjunctivitis, 71% had both asthma and rhinitis. 64% were sensitized to mite, 66% to cat, 57% to birch and 69% to grass pollen. 77% had mild asthma (GINA 1-2, n=624) and 71% had a controlled asthma. In birch and grass allergic patients, 46% and 43% were asthmatic, respectively. We found similar frequencies when patients with reported allergic rhinitis without asthma to birch and grass pollen were exposed in ALYATEC EEC in previous studies: 53% and 50% had respectively birch and grass-induced early asthma responses. <bold>Conclusion:</bold> Birch and grass pollen allergic asthma appear to be more frequent than expected according to ALYATEC database, as compared to previous studies. Grass and birch pollen allergic asthma must be better considered in future allergen immunotherapy trials.