Race is associated with differences in airway inflammation in patients with asthma.

TLDR: African American subjects exhibit greater eosinophilic airway inflammation, which might explain the greater asthma burden in this population.

Abstract: Background African American subjects have a greater burden from asthma compared with white subjects. Whether the pattern of airway inflammation differs between African American and white subjects is unclear. Objective We sought to compare sputum airway inflammatory phenotypes of African American and white subjects treated or not with inhaled corticosteroids (ICSs; ICS+ and ICS−, respectively). Methods We performed a secondary analysis of self-identified African American and white subjects with asthma enrolled in clinical trials conducted by the National Heart, Lung, and Blood Institute–sponsored Asthma Clinical Research Network and AsthmaNet. Demographics, clinical characteristics, and sputum cytology after sputum induction were examined. We used a sputum eosinophil 2% cut point to define subjects with either an eosinophilic (≥2%) or noneosinophilic ( Results Among 1018 participants, African American subjects (n = 264) had a lower FEV 1 percent predicted (80% vs 85%, P P P P  = .28; ICS− group: 39% vs 35%, P  = .65; respectively). However, when adjusted for confounding factors, African American subjects were more likely to exhibit eosinophilic airway inflammation than white subjects in the ICS+ group (odds ratio, 1.58; 95% CI, 1.01-2.48; P  = .046) but not in the ICS− group ( P  = .984). Conclusion African American subjects exhibit greater eosinophilic airway inflammation, which might explain the greater asthma burden in this population.