P14 Characteristics of T2-biomarker low severe asthma patients in the UK severe asthma registry. (12th November 2019)

• Record Type: Journal Article
• Authors: Busby, J; Pfeffer, PE; Jackson, DJ; Mansur, AH; Menzies-Gow, A; Siddiqui, S; Chaudhuri, R; Patel, M; Heaney, LG
• Is Part Of: Thorax. Volume 74(2019)Supplement 2
• Page Start: A95
• Page End: A96
• Publication Date: 2019-11-12
• Subjects: Chest -- Diseases -- Periodicals; Thorax; Chest -- Diseases; Periodicals; Periodicals; 617.54
• DOI: 10.1136/thorax-2019-BTSabstracts2019.157
• Languages: English
• ISSNs: 0040-6376

Abstract

Abstract : Background: Some patients with severe asthma have persisting symptoms despite suppression of T2-cytokine pathways with corticosteroids. Multiple mechanisms including extra-pulmonary comorbidities have previously been implicated. This analysis examined baseline demographic features in T2-biomarker low patients. Methods: Baseline demographics for patients meeting ERS/ATS criteria for severe asthma were analysed in 1, 408 non-smoking patients registered in the UK Severe Asthma Registry. The study included 119 T2-low subjects (FeNO<25 ppb, blood eosinophils <150/µL) and 613 T2-high subjects (FeNO≥25ppb, blood eosinophils ≥150/µL). Results: Asthma control (ACQ7 3.0 (1.3) v 3.1 (1.3)) and exacerbations in the 12 months prior to registration (5 (5) v 5 (4)) were similar in both groups at registration. T2-low patients were more likely to be Caucasian, have earlier onset disease and had higher BMI (32.7 (7.2) v 30.2 (6.6) kg/m 2, p<0.001). T2-low patients also had significantly lower total lung capacity and residual volume (102% (30) v 123% (45), p<0.05) with less airflow obstruction (FEV1/FVC ratio 70% (14) v 63% (14), p<0.001). T2-low patients were more likely to be on maintenance oral steroids (60% v 45%, p<0.001) and, whilst the highest historical blood eosinophil count was lower than T2-high patients (0.7 (1.9) v 1.0 (1.1)), it was still elevated consistent with corticosteroid T2-suppression. Discussion: Significant differences were evident between T2-low and T2-high patients at registration in the UKSAR. T2-low patients have a substantial symptom burden, with higher BMI and more restrictive lung function which may require additional non-pharmacological management approaches. Characterisation of symptom mechanism, including extra-pulmonary factors such as obesity, is likely to be important.