Association between IgE levels and asthma severity among African American, Mexican, and Puerto Rican patients with asthma

Background High levels of IgE are associated with asthma. Whether higher levels of IgE are associated with more severe asthma is still unclear. Objective To determine whether IgE is associated with asthma severity among Latino and African American subjects with asthma. Methods We assessed lung function and asthma severity among African American, Mexican, and Puerto Rican patients with asthma with high IgE levels (≥100 IU/mL; n=492) and compared these values to those of patients with asthma with low IgE levels ( Results Patients with asthma with high IgE had a lower mean FEV 1 (87.6 ± 17.1, percent of predicted) than patients with asthma with low IgE (91.5 ± 17.0; P = .031). Regardless of race and ethnicity, baseline FEV 1 , forced expiratory flow, and FEV 1 /forced vital capacity were lower among subjects with high IgE than among subjects with low IgE ( P = .031, P P = .0001, respectively). In addition, 54.7% of patients with asthma with high IgE had been previously hospitalized, compared with 44.1% of patients with asthma with low IgE (odds ratio, 1.33; 95% CI, 1.04-1.71). Conclusion Higher IgE is associated with lower baseline lung function and more severe asthma among these populations. Clinical implications Among patients with asthma from 3 ethnically distinct groups, total IgE levels are inversely correlated with baseline lung function and asthma severity.