Serum 25 Hydroxy Vitamin D Insufficiency Associated with Bronchial Asthma in Lucknow, India

Objectives To assess the association between serum 25 hydroxy vitamin D levels and asthma and its control in Indian children. Methods This was a prospective case-control study conducted in tertiary care hospital. Cases of asthma and healthy age-matched controls were included, aged 1-15 y, who had not received any vitamin D supplementation in the last year and had no other co-morbidity, after obtaining written informed parental consent. 25 hydroxy vitamin D insufficiency was taken below level of <= 30 ng/mL. Results Fifty asthmatics and 25 age-matched controls were recruited from August 2011-July 2012. 25 hydroxy vitamin D insufficiency was associated with occurrence of asthma (OR= 13.5; 95 % CI=4.25-42.85: p=0.000). With decreasing level of asthma control there was increasing strength of association with 25 hydroxy vitamin D insufficiency [chi(2) for trend=24.96 (p=0.000)]. Conclusions 25 hydroxy vitamin D insufficiency is associated with bronchial asthma as well as its level of control.