Vitamin D Levels Linked to Respiratory Tract Infections
Lower serum vitamin D associated with increased upper respiratory tract infection incidence
TUESDAY, Feb. 24 (HealthDay News) -- Vitamin D levels are inversely associated with upper respiratory tract infections, in a robust dose-response relationship that is clinically and statistically significant, according to research published in the Feb. 23 issue of the Archives of Internal Medicine.
Adit A. Ginde, M.D., of the University of Colorado Denver School of Medicine in Aurora, and colleagues performed a secondary analysis of the Third National Health and Nutrition Examination Survey, including 18,883 participants aged 12 years or older. Survey participants self-reported if they had recent symptoms indicative of an upper respiratory tract infection, and blood samples collected during this survey were used to determine serum levels of 25-hydroxyvitamin D [25(OH)D].
Nearly one-fifth of participants (19 percent) reported a recent upper respiratory infection. The proportion of patients reporting an upper respiratory infection decreased with increasing levels of 25(OH)D; 24 percent, 20 percent and 17 percent of participants with less than 10 ng/mL, 10 to less than 30 ng/mL, and 30 ng/mL or more 25(OH)D, respectively, reported a recent infection. The association between lower 25(OH)D levels and increased incidence of upper respiratory tract infection remained significant regardless of demographic or clinical characteristics, the researchers report.
"To our knowledge, this is the first population-based study to evaluate and demonstrate an association between serum 25(OH)D level and upper respiratory tract infection," the authors write. "Vitamin D supplementation may reduce the incidence of upper respiratory tract infection and exacerbations of respiratory tract diseases."