Clinical and Economic Burden of Uncontrolled Severe Noneosinophilic Asthma

OBJECTIVES: To quantify the clinical and economic burden of patients with severe asthma with low blood eosinophil counts (BECs) untreated with biologics. STUDY DESIGN: Retrospective cohort study in IBM MarketScan claims database. METHODS: Patients 12 years and older with severe asthma with BEC data were selected between January 1, 2013, and June 30, 2018 (date of the most recent BEC was used as the index date). Inclusion criteria were (1) presence of BEC laboratory test result, (2) continuous enrollment for 12 months preceding and following the index date, (3) meeting the Healthcare Effectiveness Data and Information Set definition of persistent asthma, (4) meeting the Global Initiative for Asthma definition of severe asthma, and (5) an absence of biologic treatment, other respiratory diagnoses, and malignancies 12 months preceding and following the index date. Asthma exacerbations, levels of disease control, and all-cause and asthma-related health care costs were reported during the 12-month postindex period for patients with a BEC less than 300 cells/mcL. RESULTS: The sample included 8073 patients with severe asthma; 78% (n = 6260) presented with a BEC less than 300 cells/mcL. Mean (SD) age of the sample was 54.8 (14.2) years; 64% were female. Eighteen percent of patients had an asthma exacerbation; 19% had either uncontrolled or suboptimally controlled asthma based on the frequency of asthma-related hospital admissions, emergency department visits, or corticosteroid prescription fills. One-year all-cause and asthma-related total health care costs were $25,845 and $2802, respectively. Patients with suboptimally controlled and uncontrolled asthma spent $1471 and $3872 more, respectively, on asthma-related claims compared with patients with controlled asthma. CONCLUSIONS: Among patients with severe asthma with low eosinophils untreated with biologics, there is a high burden of disease among those who have suboptimal disease control, highlighting an unmet need in severe asthma treatment.