A study of IgE sensitization and skin response to histamine in Asian-Pacific American adults.

Allergic disorders and skin response to histamine have been noted to vary in different ethnicities. We investigated IgE-mediated allergic sensitization and skin response to histamine in Asian Pacific Americans (APAs), black and Hispanic Americans, and white adults. A retrospective questionnaire-based study was performed of 2222 adults presenting at a New York City allergy referral center from 1994 to 2003. Questionnaire data included sex, age, and ethnicity and personal and family history of atopic disorders. Skin-prick test (SPT) data included saline and histamine controls and response to a standardized panel of 10 aeroallergens. APA patients had a lower odds of asthma (adjusted odds ratio [aOR], 0.68; 95% confidence interval [CI], 0.52-0.89; p = 0.005) and/or animal allergies (aOR, 0.64; 95% CI, 0.50-0.82; p = 0.0003). Histamine response was not significantly different in APA (aOR, 0.90; 95% CI, 0.73-1.12; p = 0.36) or Hispanic Americans (aOR, 1.03; 95% CI, 0.85-1.24; p = 0.76), but was higher in black Americans (aOR, 2.32; 95% CI, 1.67-3.21; p < 0.0001). APA had higher odds of a positive SPT to trees (aOR, 1.49; 95% CI, 1.16-1.91; p = 0.002), grasses (aOR, 1.32; 95% CI, 1.05-1.43; p = 0.02), feathers (aOR, 1.65; 95% CI, 1.31-2.09; p < 0.0001), and cockroaches (aOR, 1.37; 95% CI, 1.10-1.62; p = 0.005). Moreover, APA had a higher total number of positive SPTs when compared with white patients (5.5 ± 3.2 versus 4.9 ± 3.3; aOR, 1.34; 95% CI, 1.10-1.62 p = 0.004). APA adults in our patient population had more IgE sensitizations but not an increased skin response to histamine. In contrast, black Americans had increased skin response to histamine.