Allergic rhinitis and serum 25-hydroxyvitamin D level in Korean adults

Background: Recently, it has been suggested that airway hyper-responsiveness, asthma, and atopic dermatitis are associated with a low vitamin D level. Objective: To evaluate whether the occurrence of allergic rhinitis (AR) is related to serum vitamin D levels in the general Korean adult population. Methods: Data obtained as part of the fourth annual Korean National Health and Nutrition Examination Survey (2009) of 8,012 adults older than 18 years were analyzed. The correlation between serum 25-hydroxyvitamin D (25[OH] D) level and presence of AR using questionnaires on symptoms, history of diagnosis of AR, and rhinoscopic findings were analyzed. All estimates were calculated based on sampling weight. Results: Mean age was 44.41 years and men constituted 49.8% of the sample. Participants with diagnosed AR constituted 11.1%. The mean 25(OH) D level of the AR group was lower than that of the non-AR group (16.71 +/- 0.30 vs 17.75 +/- 0.25 ng/mL, P<.001). A comparison of the prevalence of AR in the 3 groups showed that AR steadily decreased in the higher 25(OH) D groups (13.0% in group I [<15 ng/mL], 11.5% in group II [>= 15-<25 ng/mL], and 7.2% in group III [>= 25 ng/mL], P<.001). After adjusting for body mass index, smoking status, age, sex, sun exposure, income quartile, exercise, and body fat percentage, lower serum 25(OH) D levels remained significantly associated with the presence of AR compared with group III (hazard ratio 1.559 in group I and 1.430 in group II). Conclusion: This study suggested a potential association between low vitamin D levels and AR prevalence in Korean adults. (C) 2013 American College of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.