BOSTON—Vitamin D deficiency is common among children with mild-to-moderate asthma, and those children with asthma who are low in vitamin D are more likely to suffer asthma attacks, according to a recent study from Brigham and Women's Hospital, Boston (J Allergy Clin Immunol. 2010 Jun 8).
Asthma attacks, most often caused by respiratory tract infections, are the leading causes of asthma morbidity and comprise a significant proportion of asthma-related costs, noted the researchers. Because vitamin D status might play a role in preventing asthma exacerbations, they studied its effects on severe asthma exacerbations (aka asthma attacks).
They measured 25-hydroxyvitamin D levels in sera collected from 1,024 children with mild-to-moderate persistent asthma at the time of enrollment in Childhood Asthma Management Program, a multicenter clinical trial of children randomized to receive budesonide, nedocromil (two inhaled asthma medications) or placebo as-needed. They examined the relationship between baseline vitamin D levels and the odds of any hospitalization or emergency department visit during the four years of the trial.
Thirty-five percent of all subjects were vitamin D insufficient, as defined by a level of 30 ng/mL or less 25-hydroxyvitamin D. Mean vitamin D levels were lowest in African American subjects and highest in white subjects. After adjusting for age, sex, body mass index (BMI), income, and treatment group, insufficient vitamin D status was associated with a higher odds of any hospitalization or emergency department visit (P =0 .01).
