D1.156 - High relevance of upper airways comorbidities in T2 asthma inflammatory burden

Evaluation of type 2 (T2) asthma may be done according to different clinical phenotypes, either asthma severity or upper airways comorbidities.

Objective: To investigate if T2 inflammatory burden evaluation based on upper airway comorbidity is different than based on asthma severity.   

Asthma patients were recruited in a multicentric (23 centres) prospective study and evaluated for upper airway comorbidities, according to ARIA and EPOS criteria, and  stratified into five groups/phenotypes: no sinonasal symptoms, non-allergic rhinitis (NAR), allergic rhinitis (AR), chronic rhinosinusitis with (CRSwNP) or without (CRSsNP) nasal polyps. The same asthma population was evaluated according to GINA severity and stratified into four groups/phenotypes: intermittent, or persistent (mild, moderate or severe) asthma. Identification of type 2 inflammatory burden was done according to three T2 biomarkers: blood eosinophil count (BEC) ≥300cells/μL), total IgE (≥100IU/mL) and fractional exhaled nitric oxide (FeNO≥25 ppb). T2 biomarker expression was characterized across comorbid sinonasal phenotypes and asthma severity phenotypes in this asthma cohort. Patients with an incomplete (<3) biomarker panel were excluded for the analysis.

Most patients (N=401, 81.5%) showed T2 inflammation (≥1 T2 biomarker elevated). Among them, 207 patients (42%) had all three biomarkers recorded and were included in the analyses. Comorbid diseases were CRSwNP (N=58, 28%), CRSsNP (N=30, 14%), AR (N=78, 38%), NAR (N=36, 17%), or without nasal symptoms (N=5, 2%) while asthma severity was intermittent (N=39, 19%), mild (N= 41, 20%), moderate (N=63, 30%) and severe (N= 64, 31%). According to asthma comorbidities, the most prevalent T2 biomarkers were total IgE and FeNO in CRSwNP (74-78% ) and CRSsNP (70-74%), total IgE in AR (68%), and BEC in NAR (65%). According to comorbidities and asthma severity, the co-expression of all three T2 biomarkers was however characteristic of asthma with CRSwNP (38%) and of persistent moderate/severe asthma (26%).

Asthma with comorbid CRSwNP showed the highest T2 inflammatory burden. In addition, the asthma expression patterns of T2 biomarkers showed a higher discrimination when assessing sinonasal comorbities than when assessing asthma severity.