Correlation between serum 25-hydroxyvitamin D level and core symptoms of autism spectrum disorder in children

Abstract

Objective: To explore the relationship between serum 25-hydroxyvitamin D levels and core symptoms of autism spectrum disorder (ASD) in children. Method: In this cross-sectional study, ASD children 4 to 6 years of age who were diagnosed in Department of Developmental and Behavioral Pediatrics, First Hospital of Jilin university from January to May 2017 were assigned to ASD group, and children for routine growth and development assessment in Jilin province were assigned to control group. The two groups were well matched for age and sex, and none of them had received vitamin D supplementation. Serum 25-hydroxyvitamin D levels were measured by HPLC-MS/MS method. The patients of the ASD group were assessed with autism behavior checklist (ABC), childhood autism rating scale (CARS), social response scale (SRS), and autism treatment evaluation checklist (ATEC). The levels of vitamin D were divided into normal(>0.03 ng/L), insufficient (0.01-0.03 ng/L) and deficient (<0.01 ng/L). Levels of serum vitamin D between the two groups were compared by two independent sample t-test, and the difference in the percentages of normal, insufficient and deficient levels of vitamin D was tested by chi-square test, and correlations between vitamin D levels and the total scores or subscales of ABC, CARS, SRS and ATEC were analyzed by Pearson correlation analysis. Result: The 87 subjects in the ASD group included 75 males and 12 females, with a mean (±SD) age of (4.7±0.7) years. The 301 subjects in the control group included 249 males and 52 females, with a mean (±SD) age of (4.8±0.8) years. Serum vitamin D level in ASD children was significantly lower than that of the control group ( (0.021±0.008) vs. (0.036±0.016) ng/L, t=-8.17, P<0.01), and the between-group percentage difference of normal, insufficient and deficient levels of vitamin D was statistically significant (12 (14%) vs. 186 (62%) , 67 (77%) vs. 113 (37%) , 8 (9%) vs. 2 (1%) , χ(2)=72.1, P<0.01). There were negative correlations between serum vitamin D level in ASD children and total ABC score or ABC subscale scores (body behavior, self-care, language and social interaction)(r=-0.531,-0.397,-0.283,-0.248,-0.262, P=0.000, 0.000, 0.007, 0.020, 0.014). There were negative correlations between serum vitamin D level in ASD children and total CARS score and CARS subscale scores (imitation, nonverbal communication and general impression) (r=-0.352, -0.216, -0.248, -0.216, P=0.001, 0.046, 0.021, 0.046). There were negative correlations between serum vitamin D level in ASD children and SRS behavior subscale or ATEC social interaction subscale (r=-0.536, P=0.005, r=-0.400, P=0.014). Conclusion: Serum 25-hydroxyvitamin D level in children with ASD is obviously lower than that in the healthy control group, and there are negative correlations between vitamin D levels and core symptoms of ASD. Trial registration Chinese Clinical Trial Registry, ChiCTR-CCC-13004498.