48 Circadian Regulation of Scratching Behavior in NC/TND Mice, a Mouse Model for Human Atopic Dermatitis

current AD symptoms 18,095 questionnaires were analyzed and for severe current AD symptoms 19,173. Current AD symptoms mean global prevalence was 6.1% (95% CI, 5.7-6.4%). Mean prevalence and 95% CI per center: Monterrey 4.2% (3.5-4.9%), Mexicalli 6.3% (5.3-4.9%), Ciudad Victoria 2.3% (1.8-2.9%), Tijuana 4.9%(4.1-5.7%); North DF 8.5% (7.6-9.4%), Southeasat DF 9.4% (8.0-10.7%), Toluca 5.4% (4.6-6.2%); Veracruz 5.3% (4.3-6.2%); Villahermosa 8.6% (7.3-9.8%). Severe current AD symptoms mean global prevalence was 0.7% (95% CI, 0.6-0.9). Mean prevalence and 95% CI per center: Monterrey 0.6% (0.3-0.9%), Mexicalli 0.8% (0.5-1.2%), Ciudad Victoria 0.3% (0.1-0.6%), Tijuana 0.9% (0.5-1.2%); North DF 1.1% (0.7-1.5%), DF Southeast 1% (0.5-1.4%), Toluca 0.3% (0.1-0.5%); Veracruz 0.7% (0.4-1.1%); Villahermosa 1.2% (0.8-1.7%). Identified risk factors for current AD symptoms: presence of allergic rhinitis symptoms OR 1.94 (95% CI, 1.53-2.14; P # 0.005); conjunctivitis symptoms OR 1.81 (95% CI, 1.532.14; P # 0.005); accumulated asthma symptoms OR 1.51 (95% CI, 1.31.76; P # 0.03). Identified risk factors for severe current AD symptoms: presence of conjunctivitis symptoms OR 2.20 (95% CI, 1.42-3.4; P # 0.005); accumulated asthma symptoms OR 2.16 (95% CI, 1.38-3.39; P # 0.005); use of acetaminophen in the first year of life OR 1.80 (95% CI, 1.212.69; P # 0.005). Conclusions: Current AD symptoms prevalence was higher at north DF, followed by Toluca and southeast DF; current severe AD symptoms were higher at Villahermosa, followed by north DF and Tijuana. The presence of rhinoconjuntivitis and accumulated asthma symptoms doubles the risk for current AD and current severe symptoms in Mexican children and Acetaminophen use in the first year of life was associated with severe current AD symptoms.