Correlation Between Tic Disorders and Serum 25-Hydroxyvitamin D Levels in Chinese Children

OBJECTIVE: To explore the correlation between serum 25-hydroxyvitamin D levels and tic disorders (TDs) in Chinese children. METHODS: We selected 2960 children with TD and 2665 healthy controls, aged 5–14 years, from the Department of Neurology of the Shanghai Children’s Hospital. Serum 25-hydroxyvitamin D levels and degrees of vitamin D deficiency were compared between patients with TD and healthy children. RESULTS: The mean serum 25-hydroxyvitamin D level in the TD group was significantly lower than that in the control group (P < 0.001). The proportion of patients with 25-hydroxyvitamin D deficiency in the TD group was significantly higher than that in the control group. However, there was no correlation between 25-hydroxyvitamin D deficiency and the severity of TD. In addition, for age-wise comparison, mean levels of 25-hydroxyvitamin D and its deficiency in the TD group were the most significant in children over 9 years of age. CONCLUSION: There is a correlation between 25-hydroxyvitamin D deficiency and TD in Chinese children, but not between 25-hydroxyvitamin D deficiency and the severity of TD. There was a correlation between age and deficiency of 25-hydroxyvitamin D; this deficiency was most pronounced among those over the age of 9 years.