Vitamin-D Deficiency in Asthmatic Children and Adolescents from Northern India - A Hospital Based Prospective Study

Background: Vitamin-D plays a key role in bronchial asthma due to its immune modulatory effect. It is known to be associated with airway hyper-responsiveness, decreased pulmonary function, impaired asthma control and steroid resistance. In asthmatic children, vitamin-D3 levels lower than 30ƞg/mL are shown to increase number of asthma exacerbations.

Objectives: To estimate serum vitamin-D levels in asthmatic children and to evaluate the effect of vitamin D deficiency on disease progression and response to therapy.        

Methods: This prospective observational study was carried in a tertiary level care hospital in one of the northern states of India over a period of 18 months. Inclusion criteria: All consecutive children aged between 1-18 years with bronchial asthma coming to pediatric inpatient and outpatient clinics were studied. Children with significant renal pathology, rickets, autoimmune diseases, chronic malabsorption, liver disease and those who refused consent were excluded. Ethical approval: Obtained from Institute Ethics committee[IEC/18/154].These children were subjected to vitamin D estimation after written informed consent and clinical data monitoring.  

Results: Out of 131 bronchial asthma patients, three fourths of children [75.6%] had Vitamin D deficiency and 25% had positive family history. The Median (IQR) serum vitamin-D levels were 15.5 (8.8) ƞg/mL. Children in the vitamin-D deficient group had the largest proportion of partially controlled and uncontrolled asthma.

Conclusion: The prevalence of Vitamin D deficiency in asthmatic children in our study was 75.6%. Vitamin D deficiency was associated with increasing severity of asthma and poor disease control.