BACKGROUND Insufficient vitamin D activity has attracted increasing interest as a possible underlying risk factor in disorders of the central nervous system, including autism. METHODS In this study, 25-hydroxyvitamin D (25(OH)D) was analysed in 58 Sweden-born sibling pairs, in which one child had autism spectrum disorder (ASD) and the other did not. The study group consisted of two representative samples; 47 Gothenburg sibling pairs with mixed ethnicities and 11 Stockholm sibling pairs with Somali background. 25(OH)D levels were analysed in the stored dried blood spots taken in the neonatal period for metabolic screening. RESULTS The collapsed group of children with ASD had significantly lower vitamin D levels (M = 24.0 nM, SD = 19.6) as compared with their siblings (M = 31.9 nM, SD = 27.7), according to a paired samples t-test (P = 0.013). The difference was - most likely - not only accounted for by a difference in season of birth between ASD and non-ASD siblings since the mean 25(OH)D levels differed with similar effect size between the sibling pairs born during winter and summer, respectively. All children with African/Middle East background, both the children with ASD and their non-ASD siblings, had vitamin D deficiency. CONCLUSIONS The findings suggest that low prenatal vitamin D may act as a risk factor for ASD, however, there is a need for replication with larger samples. Future research should study whether or not adequate supplementation of vitamin D to pregnant women might lower the risk for ASD in the offspring.

中文翻译：

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自闭症谱系障碍和出生时维生素D含量低：同级对照研究。

背景技术维生素D活性不足已引起越来越多的关注，作为可能是包括自闭症在内的中枢神经系统疾病的潜在危险因素。方法在本研究中，对58例瑞典出生的兄弟姐妹对中的25-羟基维生素D（25（OH）D）进行了分析，其中一个孩子患有自闭症谱系障碍（ASD），另一个孩子没有。该研究组由两个代表性样本组成。47个哥德堡兄弟姐妹对与混合种族，11个斯德哥尔摩兄弟姐妹对与索马里背景。分析新生儿时期采集的干燥血斑中的25（OH）D水平，以进行代谢筛查。结果根据配对样本t检验（P检验），与同胞兄弟姐妹（M = 31.9 nM，SD = 27.7）相比，崩溃的ASD儿童组的维生素D水平明显降低（M = 24.0 nM，SD = 19.6）。 = 0.013）。这种差异很可能不仅是由ASD兄弟姐妹和非ASD兄弟姐妹在出生季节上的差异造成的，因为平均25（OH）D水平在冬季和夏季出生的兄弟姐妹对之间分别具有相似的效应大小。 。所有患有非洲/中东背景的儿童，无论患有ASD的儿童还是非ASD的兄弟姐妹，都患有维生素D缺乏症。结论研究结果表明，低产前维生素D可能是ASD的危险因素，但是，需要大量样品进行复制。未来的研究应研究孕妇是否适当补充维生素D可能会降低后代发生ASD的风险。