Outdoor exposure and vitamin D levels in urban children with asthma

Sonali Bose, Patrick N. Breysse, Meredith C. McCormack, Nadia N. Hansel, Robert R. Rusher, Elizabeth Matsui, Roger Peng, Jean Curtin-Brosnan, Gregory B. Diette

Research output: Contribution to journalArticlepeer-review

Abstract

Background: The inner-city pediatric population in the United States has a disproportionate burden of asthma. Recent attention has focused on the immunomodulatory role of vitamin D, which may be protective against disease morbidity. As the primary determinant of vitamin D status in humans is exposure to sunlight, we aimed to determine if 25-OH vitamin D levels in urban preschool children with asthma were low, influenced by time spent outdoors, and associated with asthma morbidity. Methods. Serum 25-OH vitamin D levels were measured at baseline in a cohort of 121 inner-city children ages 2-6 years with asthma in Baltimore, MD. Participants were followed longitudinally at 3 and 6 months to assess time spent outdoors, asthma symptoms through questionnaires and daily diaries, and allergic markers. Results: In a predominantly black population of preschool children, the median 25-OH vitamin D level was 28 ng/mL (IQR 21.2-36.9), with 54% of the children below the traditionally sufficient level of 30 ng/mL and 7.4% in the range associated with risk of rickets (< 15 ng/mL). The median time spent outdoors was 3 hours/day (IQR 2-4), and greater time spent outdoors was not associated with higher vitamin D levels. 25-OH vitamin D did not show seasonal variation in our cohort (p = 0.66). Lower 25-OH levels were correlated with higher IgE levels. Conclusions: Urban African-American preschool children with asthma have high rates of vitamin D insufficiency, and increased outdoor exposure is unlikely to correct these low 25-OH vitamin D levels. Repletion in this population may require dietary supplementation.

Original languageEnglish (US)
Article number81
JournalNutrition Journal
Volume12
Issue number1
DOIs
StatePublished - 2013

Keywords

  • Asthma
  • Exposure
  • Outdoor
  • Ultraviolet
  • Vitamin D

ASJC Scopus subject areas

  • Medicine (miscellaneous)
  • Nutrition and Dietetics

Fingerprint Dive into the research topics of 'Outdoor exposure and vitamin D levels in urban children with asthma'. Together they form a unique fingerprint.

Cite this