CERSI Collaborator: University of California San Francisco: Esteban González Burchard, MD, MPH

FDA Collaborators: Richardae Araojo, PharmD, MS (OMHHE); Christine Lee, PharmD, PhD; Christine Merenda, RN; Ronald Rabin, MD

Project Start Date: 02/2020
Project End Date: 08/2021

Regulatory Science Challenge

Asthma is an obstructive inflammatory lung disease that can profoundly affect the day to day lives of children and adults. Asthma prevalence and severity vary by race and ethnicity, and asthma-related deaths are higher in minority patients, particularly Puerto Ricans and Black or African Americans, than in White patients. Unfortunately, despite the high burden of disease, morbidity, and mortality of asthma in Puerto Rican and Black or African American populations, only a small number of asthma studies focus on racial and ethnic minority populations.

It is still not clear why certain racial and ethnic populations have higher asthma prevalence and more severe asthma cases than other populations. It is known that important asthma-associated blood parameters, such as serum total immunoglobulin E (IgE) and white blood cell counts, can vary among different racial and ethnic minority populations. These blood parameters are used to distinguish the different subtypes of asthma and inform the choice of asthma therapy, but much of therapeutic decision-making is based on studies conducted primarily in populations of European origin. Understanding the racial and ethnic differences in asthma subtypes may help explain population-specific trends in asthma outcomes.

Project Description and Goals

Our objective is to produce population-specific profiles of asthma severity, exacerbations, and control for three predominant minority populations: Puerto Rican, Black or African American, and Mexican American pediatric patients. We used our large database that contains detailed clinical profiles from these populations, which included common patient visit data such as obesity, asthma medication use, and sensitivity to allergens, as well as biological data such as serum IgE levels, white blood cell counts, asthma medication response, and other variables. We mapped these variables and analyzed them to determine if the major biological factors involved in severe asthma differ among minority populations.

Research Outcomes/Results

Race and ethnicity were found to be important factors in the relationship between the blood parameter IgE and asthma exacerbations. Elevated IgE levels are associated with worse asthma outcomes in Puerto Ricans. Allergic asthma was associated with worse outcomes in Mexican Americans, whereas non-allergic, or eosinophilic, asthma was associated with worse outcomes in Puerto Ricans. A lower proportion of Puerto Ricans met dosing criteria for allergic asthma-directed biologic therapy than other groups. A higher proportion of Puerto Ricans qualified for eosinophilic asthma-directed biologic therapy than African Americans.

Research Impacts

Researchers found population-specific associations between blood parameters and asthma subtypes with asthma outcomes. Their findings suggest that eligibility for asthma biologic therapies differs across pediatric racial and ethnic populations. These findings call for more studies in diverse populations for equitable treatment of minority patients with asthma.

Publications

Wohlford EM, Huang PF, Elhawary JR, Millette LA, Contreras MG, Witonsky J, Holweg CTJ, Oh SS, Lee C, Merenda C, Rabin RL, Araojo R, Mak ACY, Eng CS, Hu D, Huntsman S, LeNoir MA, Rodríguez-Santana JR, Borrell LN, Burchard EG. Racial/ethnic differences in eligibility for asthma biologics among pediatric populations. J Allergy Clin Immunol. 2021 Nov;148(5):1324-1331.e12. doi: https://doi.org/10.1016/j.jaci.2021.09.005. Epub 2021 Sep 16. PMID: 34536416.