To Explore The Role Of Serum 25-hydroxy Vitamin D₃ In Young Children With Common Respiratory Diseases

Objectives: To measure serum 25-hydroxyvitamin D₃（25-（OH）D₃）level in infants,investigate correlation of serum 25-（OH）D₃ level with recurrent wheezing,capillary bronchitis,recurrent respiratory tract infection（RRI）and community-acquired pneumonia（CAP）.Methods: 1.A total of 200 outpatient infants of pediatric department of Tianjin People′s hospital from January 2015 to April 2016 were selected as patients in this study.Including.2.Both serum 25-（OH）D₃ level and serum Ig E level were measured for all;MP-Ig M、liver function、Myocardial enzyme were measured for all patients.3.The patients in capillary bronchitis group and CAP group were divided into groups according to the severity of disease,and to observe the influence of serum level of 25（OH）D₃ on the severity of the disease.4.Multivariate analysis was performed to investigate the risk factors of recurrent wheezing,including family history of asthma,activity amount,whether bask in the sunshine,whether premature,smoking history,serum 25-（OH）D₃ levels.5.Vit D deficiency children in repeated wheezing and RRI groups were treated with Vit D for 3 months and followed up for one yearResults: 1.For control group,CAP group,capillary bronchitis group,RRI group,and recurrent wheezing group,serum 25-（OH）D₃ level was decreased sequentially,and the differences were statistically significant,P values were all < 0.001.Whereas total Ig E levels of recurrent wheezing group and capillary bronchitis group were both obviously higher than that of normal control group,and the differences were statistically significant,P values were all < 0.001.2.Proportion of infants having serum 25-（OH）D₃ deficiency was abnormally decreased in recurrent wheezing group,RRI group,capillary bronchitis group,CAP group and normal control group,the differences were statistically significant,P values were all < 0.05.Proportion of infants having serum 25-（OH）D₃ deficiency in each disease group was obviously higher than that in normal control group,and the differences were statistically significant,P values were all < 0.05.Whereas among each disease groups,the differences were not statistically significant,P values were all > 0.05.3.Infants from capillary bronchitis group were divided into two groups according to the disease severity.It was found that serum 25-（OH）D₃ level of severe disease group was obviously lower than that of mild disease group,and the difference was statistically significant,P value was < 0.05.Severity of capillary bronchitis had some correlation with serum 25-hydroxyvitamin D₃ level.4.Infants from CAP group were divided into two groups according to disease severity.It was found that serum 25-（OH）D₃ level of severe disease group was obviously lower than that of mild disease group,and the difference was statistically significant,P value was < 0.05.It was shown that severity of CAP had some correlation with serum 25-（OH）D₃ level.For various disease groups,the differences between mycoplasma pneumonia positive and negative groups in serum 25-（OH）D₃ level were not statistically significant,P values were all > 0.5.5.For each disease groups,the differences of serum 25-（OH）D₃ level between mycoplasma pneumonia positive and negative group were not statistically significant,P values were all > 0.5.6.Analysis of non-dietary factors showed that there were no difference in family history of asthma,amount of physical activity,whether exposure to sunlight,premature or full-term birth between groups,P values were all > 0.05.It was shown that history of smoking exposure had a positive correlation with recurrent wheezing,P value was < 0.05.7.Multiple regression analysis showed that deficiency of 25-（OH）D₃,little sunlight exposure,family history of asthma,small amount of physical activity,elevated serum Ig E level and BMI could increase risk of wheezing,P values were all < 0.001.8.Vit D deficiency children in repeated wheezing and RRI groups were treated with Vit D for 3 months and followed up for one year,and it showed that the number of attacks decreased obviously than before treatment,and the difference was statistically significant,P value was < 0.05.Conclusions: 1.Serum 25-（OH）D₃ level had a correlation with incidence of recurrent wheezing,capillary bronchitis,RRI,and CAP in infants.2.For infants suffering from capillary bronchitis and RRI,serum 25-（OH）D₃ level had a negative correlation with total Ig E level.It is suggested that 25-（OH）D₃ may play a supporting role in the prevention and treatment of allergic diseases in infants.Serum 25-（OH）D₃ levels can affect the severity of capillary bronchitis and CAP,the lower the level of serum 25-（OH）D₃,the more serious the disease.3.Vit D deficiency may promote the development of recurrent respiratory tract infection and recurrent wheezing,Supplement of Vit D can reduce the number of episodes of children with Vit D deficiency.