Department of Psychiatry, University of California-Davis, Sacramento, California 95817, USA.
Pediatrics. 2011 Sep;128(3):e488-95. doi: 10.1542/peds.2010-2825. Epub 2011 Aug 15.
The recurrence risk of autism spectrum disorders (ASD) is estimated to be between 3% and 10%, but previous research was limited by small sample sizes and biases related to ascertainment, reporting, and stoppage factors. This study used prospective methods to obtain an updated estimate of sibling recurrence risk for ASD.
A prospective longitudinal study of infants at risk for ASD was conducted by a multisite international network, the Baby Siblings Research Consortium. Infants (n = 664) with an older biological sibling with ASD were followed from early in life to 36 months, when they were classified as having or not having ASD. An ASD classification required surpassing the cutoff of the Autism Diagnostic Observation Schedule and receiving a clinical diagnosis from an expert clinician.
A total of 18.7% of the infants developed ASD. Infant gender and the presence of >1 older affected sibling were significant predictors of ASD outcome, and there was an almost threefold increase in risk for male subjects and an additional twofold increase in risk if there was >1 older affected sibling. The age of the infant at study enrollment, the gender and functioning level of the infant's older sibling, and other demographic factors did not predict ASD outcome.
The sibling recurrence rate of ASD is higher than suggested by previous estimates. The size of the current sample and prospective nature of data collection minimized many limitations of previous studies of sibling recurrence. Clinical implications, including genetic counseling, are discussed.
自闭症谱系障碍（ASD）的复发风险估计在 3%至 10%之间，但之前的研究受到样本量小以及与确定、报告和停止因素相关的偏倚的限制。本研究采用前瞻性方法获得了 ASD 同胞复发风险的最新估计。
通过一个多地点国际网络——婴儿兄弟姐妹研究联盟，对有 ASD 高风险的婴儿进行了一项前瞻性纵向研究。从婴儿生命早期开始对 664 名具有 ASD 患病年长同胞的婴儿进行跟踪，直到他们 36 个月时，对他们进行 ASD 分类。ASD 的分类需要超过自闭症诊断观察量表的截止值，并由专家临床医生做出临床诊断。
共有 18.7%的婴儿发展为 ASD。婴儿性别和存在>1 个患病年长同胞是 ASD 结局的显著预测因素，如果是男性，风险增加近三倍，如果有>1 个患病年长同胞，风险增加两倍。研究入组时婴儿的年龄、婴儿年长同胞的性别和功能水平以及其他人口统计学因素均不能预测 ASD 的结局。
ASD 的同胞复发率高于之前的估计。当前样本量较大且数据收集具有前瞻性，最大限度地减少了之前有关同胞复发研究的许多局限性。讨论了包括遗传咨询在内的临床意义。
