Eosinophil count testing in patients with asthma varies by healthcare provider type in the US

Abstract

Abstract Background Patients with asthma with an eosinophilic phenotype may be eligible for additional treatment options to improve disease control; however, the prevalence and frequency of eosinophil testing is unknown. This study assessed blood eosinophil count testing prevalence in patients with asthma by healthcare provider (HCP) type and exacerbation frequency. Methods This was a retrospective, longitudinal, real-world study (GSK ID: 214470) utilizing the Merative Explorys® Universe electronic health records database. Eligible patients had ≥ 2 asthma diagnostic codes (January, 2016–December, 2018) (Index date: first asthma diagnosis). Outcomes included patient demographics and clinical characteristics (12-months pre-index [baseline]), and prevalence of blood eosinophil count testing, stratified by primary HCP (Allergist/Pulmonologist, a primary care physician [PCP] or other HCP) or by exacerbation frequency (frequent exacerbations [≥ 2] or infrequent exacerbations [< 2]) during the 12 months post-index (follow-up). Results Of 400,254 patients included (mean age: 51.2 years; 70.8% female), the most common provider type at baseline was a PCP (76.8%). More patients in the Allergist/Pulmonologist subgroup had ≥ 1 blood eosinophil count test result compared with patients in the PCP subgroup at both baseline (59.9% vs. 50.7%) and follow-up (59.0% vs. 56.2%). A higher proportion of patients with frequent exacerbations had blood eosinophil count tests at baseline (55.4–69.5%) and follow-up (67.9–75.1%), compared with patients with infrequent exacerbations (55.5–63.7%, 62.4–67.3%). In the total population, the mean (SD) number of tests ordered was 3.4 (5.3) and 4.1 (6.4) during the baseline and follow-up periods, respectively. A greater number of tests were ordered for patients with frequent exacerbations, most apparently in the Allergist/Pulmonologist subgroup during baseline and follow-up (7.4 vs. 4.9). For patients with frequent exacerbations with a blood eosinophil count test result, the mean (SD) number of tests ranged from 3.1 (4.6) to 5.8 (8.3) at baseline and 5.1 (8.5) to 7.4 (10.6) during follow-up. Conclusions The prevalence of BEC testing in patients with asthma remains suboptimal. Routine BEC testing should be considered by HCPs for patients with asthma, increasing identification of the eosinophilic asthma phenotype, which may inform the decision to consider advancing to targeted biologic therapy.