Geographic variation in disease burden among patients with severe persistent asthma in the United States

Carlos A Camargo Jr; Pallavi B Rane; Andrew F Beck; Yan Wang; Yen Chung; Catherine B McGuiness; Jean-Pierre Llanos; Andrew W Lindsley; Christopher S Ambrose; Zifan Zhou; Hsiu-Ching Chang; Rolin L Wade

doi:10.1016/j.anai.2023.12.016

Geographic variation in disease burden among patients with severe persistent asthma in the United States

Ann Allergy Asthma Immunol. 2023 Dec 22:S1081-1206(23)01501-6. doi: 10.1016/j.anai.2023.12.016. Online ahead of print.

Authors

Affiliations

¹ Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts.
² Amgen Inc., Thousand Oaks, California. Electronic address: prane@amgen.com.
³ Cincinnati Children's Hospital Medical Center and University of Cincinnati College of Medicine, Cincinnati, Ohio.
⁴ Amgen Inc., Thousand Oaks, California.
⁵ AstraZeneca, Gaithersburg, Maryland.
⁶ IQVIA, Plymouth Meeting, Pennsylvania.

PMID: 38141810
DOI: 10.1016/j.anai.2023.12.016

Abstract

Background: In the United States, a few studies have evaluated geographic variation of severe asthma at the subnational level.

Objective: To assess state-level geographic variation in the prevalence and characteristics of severe persistent asthma in the United States.

Methods: Patients aged above or equal to 12 years with severe persistent asthma were identified using nationally representative data from IQVIA open-source Medical/Pharmacy Claims and PharMetrics Plus databases (January 2019-December 2020). The index date was defined as the patient's earliest qualifying date for a severe asthma diagnosis. Baseline characteristics were measured during the 12-month pre-index period. Outcomes including exacerbation occurrence, asthma control, and medication use were measured during the 12-month post-index period and compared across states using census-level projections.

Results: A total of 2,092,799 patients with asthma were identified; 496,750 (23.7%) met criteria for severe persistent asthma and all inclusion criteria. Mean age was 50.5 years; 68.4% were females. The prevalence of severe persistent asthma varied across states, ranging from 19.6% (New Mexico) to 31.9% (Alaska). Among patients with severe persistent asthma, 40.9% had more than or equal to 1 exacerbation, ranging from 34.2% (Vermont) to 45.6% (Louisiana); 21.1% had uncontrolled disease, ranging from 16.5% (Vermont) to 24.0% (Arizona). Among patients with exacerbations, 13.7% had exacerbation-related emergency department visits or hospitalizations, ranging from 7.0% (North Carolina) to 17.7% (Nevada). Among patients with severe uncontrolled asthma, 15.6% used biologics post-index, ranging from 2.2% (Hawaii) to 27.9% (Mississippi).

Conclusion: There is significant variability in severe persistent asthma prevalence and disease burden across US states. Reasons for geographic variation may include differences in socioeconomic/environmental factors or asthma management.