Geographic Variation in Disease Burden Among Patients With Severe Persistent Asthma in the United States

To evaluate the prevalence and characteristics of severe persistent asthma in the United States at a state level.Patients 12 years and older with severe persistent asthma, defined by Global Initiative for Asthma guideline criteria.This retrospective cohort study used IQVIA prescription and medical claims and PharMetrics Plus databases from Jan 2019 to December 2020, examining baseline characteristics measured 12 months before meeting criteria for severe persistent asthma. Outcome characteristics, including exacerbation occurrence, asthma control, and medication use, were also measured 12 months after meeting criteria. Measurements were compared across states.The prevalence of severe persistent asthma was the least in New Mexico (19.6%) and greatest in Alaska (31.9%). Asthma exacerbations measured as one or more exacerbations of those with severe persistent asthma were recorded the least in Vermont (34.2%) and the most in Louisiana (45.6%). Vermont had the least measured uncontrolled disease at 16.5%, whereas Arizona had the most uncontrolled disease at 24%. Exacerbation-related emergency department visits were least experienced in North Carolina with 7.0%, and most experienced in Nevada with 17.7%. Those with severe uncontrolled asthma used biologics after diagnosis the most in Mississippi at 27.9% and the least in Hawaii at 2.2%.Variability in severe persistent asthma prevalence and disease burden is demonstrated throughout the United States. Many patients experience exacerbations and poor control of asthma. The reasons for the geographical variations are multifactorial, considering social determinants of health that affect access to care, clinical factors like obesity, and environmental exposures, such as allergens, air pollution, and weather.Asthma, a chronic inflammatory disorder of the airways affects approximately 8% of those living in the United States, with 24% of patients diagnosed with asthma in this study classified as severe persistent asthma, including over 36,000 adolescents. This population may incur up to 50% of total asthma costs, creating a disproportionately high medical burden. Satisfactory asthma control remains unmet for those with severe asthma. Understanding geographic variations may help uncover disparities of the disease and create an approach to resolve burdens of unmet medical needs.