Vitamin D status in autism spectrum disorders and the efficacy of vitamin D supplementation in autistic children

Abstract

Objectives: Autism spectrum disorder (ASD) is a developmental disorder characterized by pervasive deficits in social interaction, impairment in verbal and non-verbal communication, and stereotyped patterns of interests and activities. Vitamin-D deficiency was previously reported in autistic children. However, the data on the relationship between vitamin D deficiency and the severity of autism are limited.

Methods: We performed a case–controlled cross-sectional analysis conducted on 122 ASD children, to assess their vitamin D status compared to controls and the relationship between vitamin D deficiency and the severity of autism. We also conducted an open trial of vitamin D supplementation in ASD children.

Results: Fifty-seven percent of the patients in the present study had vitamin D deficiency, and 30% had vitamin D insufficiency. The mean 25-OHD levels in patients with severe autism were significantly lower than those in patients with mild/moderate autism. Serum 25-OHD levels had significant negative correlations with Childhood Autism Rating Scale (CARS) scores. Of the ASD group, 106 patients with low-serum 25-OHD levels (<30 ng/ml) participated in the open label trial. They received vitamin D3 (300 IU/kg/day not to exceed 5000 IU/day) for 3 months. Eighty-three subjects completed 3 months of daily vitamin D treatment. Collectively, 80.72% (67/83) of subjects who received vitamin D3 treatment had significantly improved outcome, which was mainly in the sections of the CARS and aberrant behavior checklist subscales that measure behavior, stereotypy, eye contact, and attention span.

Conclusion: Vitamin D is inexpensive, readily available and safe. It may have beneficial effects in ASD subjects, especially when the final serum level is more than 40 ng/ml.

Trial registration number: UMIN-CTR Study Design: trial Number: R000016846.

Keywords:

• Autism
• Neurodevelopmental
• Children
• Vitamin D

Disclaimer statements

Contributors K.S., J.J.C., G.B. and M.K.A.-R. conceptualized and designed the study protocol development, assessment, and writing manuscript. A.A.A.-R., Y.M.E., A.A.Al-A., N.H.R. A.El-A., and A.M.A. performed all clinical and neuropsychiatric assessments of all cases and reviewed and revised the manuscript. H.A.K.O. performed all lab investigations. A.A.El-H., K.A.A.El-B., and A.E.A. designed the data collection instruments, and coordinated and supervised data collection. All authors approved the final manuscript as submitted and agree to be accountable for all aspects of the work.

Funding None.

Conflicts of interest J.J.C. is president of the non-profit Vitamin D Council and receives remuneration from Purity Products. The other authors declare no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Ethics approval The Ethical Committee of Assiut University, Assiut, Egypt, approved the study. All methods and procedures used in this study were approved by the Institutional Review Board at Assiut University, Egypt. Informed consent followed the guidelines set forth by the Institutional Review Board at Assiut University and included a brief description of study procedures, potential benefits and risks, a discussion of the voluntary nature of the study, right to withdraw without consequences, and confidentiality of information. Informed consents were written in Arabic language that was age appropriate for all participants in the study. Prior to participation in the study, children were required to give their assent and parents were required to give consent for participation. Finally, participants were given a Participant's Bill of Rights.