Background: National asthma guidelines recommend that patients with persistent asthma regularly use an inhaled corticosteroid (ICS) in addition to as-needed albuterol, yet recent debates question whether this combination is equally efficacious in all ethnicities.
Objective: To examine the effect of ICS use on bronchodilator responsiveness to albuterol in 3 different ethnic populations.
Methods: A cross-sectional study of 106 Mexican Americans, 246 Puerto Ricans, and 163 African Americans with physician-diagnosed persistent asthma. Asthma severity, ethnicity, and medication use were evaluated using spirometry and questionnaires. Percentage change in forced expiratory volume in 1 second (FEV) was compared in patients who used ICSs vs those who used a short-acting beta2-agonist as their only asthma medication.
Results: Inhaled corticosteroid use was associated with improvements in the percentage change in FEV1 after albuterol administration in Mexican Americans (21.7%, P = .01) and Puerto Ricans (18.5%, P = .02) but not in African Americans (3.0%, P = .73).
Conclusions: Inhaled corticosteroid use is associated with augmented bronchodilator responsiveness to albuterol in Mexican Americans and Puerto Ricans, but not in African Americans, with persistent asthma. This underscores the need for an improved understanding of ethnic-specific drug-drug interactions, particularly in those subgroups experiencing the highest burden of asthma morbidity and mortality in the United States.