US prevalence of self-reported peanut, tree nut, and sesame allergy: 11-year follow-up.

Background: Allergy to peanuts and tree nuts (TNs) is the leading cause of fatal allergic reactions in the United States, and the prevalence appears to be increasing.

Objectives: We sought to determine the US prevalence of self-reported peanut, TN, and sesame allergy in 2008 and compare results with comparable surveys conducted in 1997 and 2002.

Methods: A nationwide, cross-sectional, random telephone survey for peanut and TN allergy was conducted with a previously used questionnaire, with additional questions about sesame.

Results: A total of 5,300 households (13,534 subjects) were surveyed (participation rate, 42% vs 52% in 2002 and 67% in 1997). Peanut allergy, TN allergy, or both was reported by 1.4% of subjects (95% CI, 1.2% to 1.6%) compared with 1.2% in 2002 and 1.4% in 1997. For adults, the prevalence was 1.3% (95% CI, 1.1% to 1.6%), which was not significantly different from prior surveys. However, the prevalence of peanut or TN allergy for children younger than 18 years was 2.1% (95% CI, 1.6% to 2.7%) compared with 1.2% in 2002 (P = .007) and 0.6% in 1997 (P < .001). The prevalence of peanut allergy in children in 2008 was 1.4% (95% CI, 1.0% to 1.9%) compared with 0.8% in 2002 (P = not significant) and 0.4% in 1997 (P < .0001). The prevalence of childhood TN allergy increased significantly across the survey waves (1.1% in 2008, 0.5% in 2002, and 0.2% in 1997). Sesame allergy was reported by 0.1% (95% CI, 0.0% to 0.2%).

Conclusions: Although caution is required in comparing surveys, peanut allergy, TN allergy, or both continue to be reported by more than 1% of the US population (eg, >3 million subjects) and appear to be increasingly reported among children over the past decade. Sesame allergy is reported much less commonly.