P17 Association between azithromycin use and stable state blood eosinophils in COPD patients. (11th November 2022)

• Record Type: Journal Article
• Authors: Prasad, A; Echevarria, C; Steer, J; Bourke, SC
• Is Part Of: Thorax. Volume 77(2022)Supplement 1
• Page Start: A89
• Page End: A89
• Publication Date: 2022-11-11
• Subjects: Chest -- Diseases -- Periodicals; Thorax; Chest -- Diseases; Periodicals; Periodicals; 617.54
• DOI: 10.1136/thorax-2022-BTSabstracts.153
• Languages: English
• ISSNs: 0040-6376

Abstract

Abstract : Introduction: Stable-state blood eosinophil counts (BEC) are important in guiding inhaled corticosteroid (ICS) treatment in COPD. The Blood eosinophils in COPD (BECCOPD IRAS: 285200) study is an observational, cohort study assessing whether the highest of at least three BEC within the previous 24 months is a suitable surrogate for stable-state BEC. Stable state blood eosinophil counts show variability over time and multiple factors may influence BEC including bacterial load. In this sub-group analysis of the BECCOPD study participants, we investigated the association between azithromycin therapy and stable state blood eosinophils. Methods: Patients, recruited into BECCOPD, who had received azithromycin therapy for at least six months, were identified. BEC over 10 years prior to, and 1 year after enrolment were reviewed. BEC during moderate or severe exacerbations, ascertained from hospital and GP records, were excluded. Mean BEC for each patient was calculated for up to two consecutive years before and after treatment initiation and for the total study period. Paired t tests were used to compare the mean BEC. Results: 37/158 patients (23.4%) received azithromycin therapy for a minimum of nine months. Mean (SD) age 71 (6) years; mean FEV1 (SD) 48.9% (19.3); 54% male. 35 patients had BEC both before and after starting azithromycin therapy. 33/208 (15.9%) stable state BEC were <0.1 on azithromycin treatment, 35/237 (14.8%) off treatment. Discussion: Patients who were on azithromycin therapy had a higher mean stable state blood counts compared to those who were not on therapy. However, in most cases this was unlikely to influence ICS treatment decisions. Further work on a larger sample size and modelling other factors influencing BEC would be of interest.