The effect of pharmacological correction of the body’s vitamin D supply on the course of bronchial asthma in children

Introduction. Recent literature data show that vitamin D deficiency (VD) plays a role in the pathogenesis of bronchial asthma (BA), affecting the regulation of immune responses and remodeling of smooth muscles of the respiratory tract. The addition of VD to the basic therapy of BA in children is a promising area of research. Objective. To analyze the relationship of serum concentrations of 25(OH)D, periostin and TGF-β1 in blood serum, depending on the level of VD provision in children with asthma after pharmacological correction. Materials and methods. The study included 80 children aged 6 to 17 years (mean age 12 ± 3.2 years). When analyzing the results of VD-complementation, the children were divided into 4 subgroups: group 1a — 40 children with asthma before VD correction, group 1b — children with asthma after VD correction (n = 40), group 2a included 40 healthy children (comparison group) before correction, group 2b included children after correction of VD status (n = 40). Results. After taking VD, the level of 25(OH) increased in all examined children with asthma in the blood serum. The number of children with VD deficiency in children with asthma decreased from 72.5 % (n = 29) to 10.0 % (n = 29) (p = 0.000), and with VD deficiency increased 4.5 times (p = 0.001), among children with normal VD provision, the serum level was 25(OH)D increased 2.5 times (p = 0.028). In the comparison group, there was also a positive trend in children: after complementation, the number of children with VD deficiency decreased by 2 times, the number of children with VD deficiency increased by 18 %, and those with normal income by 33 %, but no statistically significant difference was found (p > 0.05). The median periostin in the group of children suffering from bronchial asthma was within the range of normal values (normal 132.4–859.6 ng/ml), but after taking VD it became statistically significantly lower than before taking VD (730.0 ng/ml [390.8; 1109.7] versus 428.0 ng/ml [365.75; 582.5], p = 0.000). The parameters of TGF-β1 were independent of VD intake and were in the range of standard values. In the course of the study, we established a negative correlation of moderate intensity between the level of 25(OH)D in the blood serum of children with asthma and the frequency of exacerbations of the disease. Conclusion. After pharmacological correction of the VD status, an increase in the level of 25 (OH) is noted in the blood serum of children suffering from asthma, and especially with mild severity of the disease. The median periostin in the group of children suffering from asthma decreased statistically significantly after taking VD, and the median TGF-β1 was independent of VD status and VD intake. A negative correlation of moderate intensity was revealed between the level of 25(OH)D in the blood serum of children with asthma and the frequency of exacerbations of the disease.