Clinical effects of vitamin D in children with asthma.

Objective: Both asthma and vitamin D deficiency are common among children. The results from studies examining the relationship between them are contradictory. The aim of this study is to determine the relationship between the clinical parameters of asthma and vitamin D status in children.

Methods: One hundred and twenty children diagnosed with asthma and followed-up in our hospital were included in the study. The control group included 74 children with no evidence of allergic disease. The eosinophil counts, IgE levels and serum 25 OH cholecalciferol [25(OH)D] levels were measured.

Results: The patient group consisted of 73 (60.8%) males and 47 (39.2%) females with a mean age of 4.4 ± 1.2 years. There was no significant difference between the patient and control groups with respect to gender and age. The mean 25(OH)D level was 21.49 ± 7.74 ng/ml in the study group and 23.94 ± 8.97 ng/ml in the control group, and this difference was not significant (p = 0.094). The patients with asthma were grouped according to their vitamin D status as 'deficient' (group 1), 'insufficient' (group 2) and 'normal' (group 3). The sociodemographic features, duration of illness, number of hospitalizations, number of sensitivities to allergens, eosinophil count and serum IgE levels were not found to be different between the groups. However, the total number of exacerbations, asthma severity and systemic glucocorticoid need in the previous year were significantly higher in the deficiency group (p < 0.05).

Conclusion: Vitamin D levels were not significantly different in patients with asthma. Vitamin D deficiency was common in the study group as well as in the control group. The clinical severity of disease, the number of exacerbations and the systemic glucocorticoid need were related to vitamin D level.