LATE-BREAKING ABSTRACT: The association between serum vitamin D deficiency and allergic symptom in pregnant women

Abstract

Background: Vitamin D has been reported to affect both natural, and acquired immunity through immune cells having vitamin D receptors such as regulatory T-cells. The co-occurrence of the high prevalence of allergic diseases and vitamin D deficiency documented globally in recent decades has prompted a hypothesis on possible association between them. Objective: To prove the association between serum vitamin D deficiency and allergic symptom. Methods: We conducted a cohort study for 3,327 pregnant women during spring and fall in 2011-2013 in Japan as an adjunct study of the Japan Environment & Children's Study. There, we timely acquired subjects' daily allergic symptom scores by sending a web-based questionnaire on some days for each participant. Of 29,434 answers on 3,327 pregnant women who participated in the study, we extracted 5,608 answers of 793 subjects, that were answered within 3 months after blood-sampling, and investigated the association between their vitamin D deficiency (serum 25(OH)D 0). Results: Serum 25(OH)D was less than 20ng/mL in 575 of 793 cases. The odds ratio for occurrence of any allergic symptom in deficient cases was 1.28 (95% CI: 1.01-1.62, p=0.041). In deficient cases, statistically significant risk elevation for allergic symptom was observed at the event of desert dust arrival (OR 1.39, 1.18-1.64, p<0.001) or pollen dispersal(OR 1.51, 1.27-1.79, p<0.001), while not in vitamin D sufficient cases (OR 1.10, 0.76-1.60, p=0.61; OR 1.14, 0.78-1.66, p=0.49). Conclusion: We showed the association between serum vitamin D deficiency and allergic symptom exacerbations in Japanese pregnant women.