The Clinical Burden of Hypereosinophilic Syndrome in a Large United States Cohort.

Abstract

There are limited real-world analyses of patients with hypereosinophilic syndrome (HES) in the United States. To describe and compare treatment patterns and disease burden between patients with diagnosed or predicted HES and those without HES with elevated blood eosinophil count (BEC). Open claims data were used to identify patients with 2 or more BECs greater than 1000 cells/μL, who were classified into 3 cohorts: patients with an HES diagnosis code (group 1), patients identified as having HES by a claims-based prediction model (group 2), and patients without HES with elevated BEC (group 3). HES-related treatments, disease manifestations, HES flares, and all-cause health care resource utilization were evaluated during the 12 months following a randomly selected elevated BEC. Group 3 was compared with groups 2 and 1, separately, using Wilcoxon rank-sum test for continuous variables and χ² test for categorical variables. The study included 212 patients in group 1, 8089 in group 2, and 132,945 in group 3. Approximately 62.3% of group 1 patients received 1 or more HES-related treatment, with corticosteroids being the most common (59.0%). The most common disease manifestations were those related to the upper airway/pulmonary (61.8%), constitutional (46.2%), dermatologic (35.8%), and gastrointestinal systems (34.4%). Among patients in group 1, 22.2%, 97.2%, and 25.9% had 1 or more inpatient, outpatient, and emergency department visit, respectively. Compared with group 3, groups 1 and 2 had more corticosteroid use and health care resource utilization (all P < .05). Patients with HES had a substantial clinical and health care resource utilization burden versus those without HES with elevated BEC.