PT  - JOURNAL ARTICLE
AU  - Ambikaipakan Senthilselvan
AU  - Selvanayagam Niruban
AU  - Kannayiram Alagiakrishnan
AU  - Jeremy Beach
TI  - Association of vitamin D with current wheeze and lung function in Canadian children
DP  - 2013 Sep 01
TA  - European Respiratory Journal
PG  - P1161
VI  - 42
IP  - Suppl 57
4099  - http://erj.ersjournals.com/content/42/Suppl_57/P1161.short
4100  - http://erj.ersjournals.com/content/42/Suppl_57/P1161.full
SO  - Eur Respir J2013 Sep 01; 42
AB  - Asthma is a common chronic condition affecting Canadian children. Vitamin D modifies airway inflammation and appears important in immunity against respiratory infections, and so is potentially beneficial in asthma. However, to date studies have reported contradictory results on the relationship of vitamin D with respiratory outcomes. The objective of our study was to determine the association of vitamin D levels with current wheeze and lung function. Data on serum 25-hydroxy vitamin D [25(OH)D], respiratory symptoms, and lung function were obtained for 1,213 children aged 6 to 12 years from the Canadian Health Measures Survey. The 25(OH)D levels were categorized into three categories: 49 nmol/l or lower (low); 50 to 74 nmol/l (moderate); and 75 nmol/l or greater (high). The prevalence of current wheeze was 11.4%, 4.1% and 7.7% in the low, moderate and high vitamin D categories, respectively. Multivariate analyses confirmed that children in the low and high 25(OH)D categories were more likely to report current wheeze in comparison to those in the moderate category (odds ratio(OR): 3.26, 95% CI: 1.16-9.17; OR:2.14, 95% CI: 1.07-4.28). Lung function parameters varied significantly between vitamin D levels with the highest mean values observed among children in the moderate vitamin-D category. The dose-response relationship between 25(OH)D levels and respiratory health outcomes was U-shaped with children in the low and high 25(OH)D categories having an increased risk of asthma symptoms and lower mean lung function values in comparison to the moderate 25(OH)D category. Clearer guidelines for optimal serum vitamin D levels are required to improve respiratory health in children.