Relationship between 25-hydroxyvitamin D levels and inflammatory factors in children with asthma attack.

The level of 25-hydroxyvitamin D [25-(OH)D] associated with inflammatory factors in children during an asthma attack was investigated. In total, 60 child patients, who were admitted and treated in the Affiliated Children's Hospital of Xuzhou Medical University from March 2015 to March 2017, during their asthma attacks, were selected as the observation group. The patients were divided into the high 25-(OH)D (n=28) and low 25-(OH)D (n=32) groups according to the median level of 25-(OH)D. A total of 30 healthy children were selected as the control group. Biochemical indexes, humoral immunity, the level of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) contents as well as pulmonary function indexes were examined. The correlations in the levels of 25-(OH)D, IL-6 and TNF-α were also analysed. The results showed that the quantities of leukocytes, neutrophils and eosinophils of patients in the observation group were significantly increased compared with those in the control group (P<0.05). The contents of IL-6 and TNF-α in the observation group were obviously higher than those in the normal control group (P<0.05). The contents of serum IL-6 and TNF-α in the high 25-(OH)D group were lower than those in the low 25-(OH)D group 3 days after treatment (P<0.05). Moreover, the treatment effect in the high 25-(OH)D group was better than that in the low 25-(OH)D group (P<0.05). In addition, 25-(OH)D had a positive correlation with pulmonary function indexes (P<0.05), while TNF-α and IL-6 were negatively associated with pulmonary function indexes (P<0.05). The serum 25-(OH)D level in asthmatic children was negatively associated with the levels of inflammatory factors TNF-α and IL-6. The results showed that the level of 25-(OH)D was decreased in children with asthma attack, which is associated with the inflammatory mediators, IL-6 and TNF-α, as well as pulmonary functions (P<0.05). Therefore, the level of 25-(OH)D can be used as a test indicator for the prevention and control of childhood asthma.