秉承知乎先问是不是再问为什么的严谨习惯,先明确问题:
自闭症谱系(ASD)中的性别焦虑(GD)发生率是否高于全人群中的性别焦虑(GD)的发生率?
之前有很多著名医师的个人经验总结报道了自闭症谱系与性别焦虑高发生率的相关性,但是个人经验并不能作为充分的依据,需要严谨设计的相关统计学研究来给出答案。
经过检索发现,这个研究方向上,经过严谨设计的相关统计学研究目前来说还是不算太多,并且缺乏统一标准的多中心研究。
不过幸运的是,在论文总数较少的这样一个方向上,还是已经可以找到一篇Meta综述,即 参考文献[1]:Gender dysphoria and autism spectrum disorder: A systematic review of the literature,这篇Meta综述参考的数据量相当多,综合了19篇独立研究的数据,几乎是该方向2016年以前全部的研究了。
以下先介绍一下这篇Meta综述的内容:
文章首先总结了既往文献中统计出的性别焦虑(GD)在全人群中的发生率:
The prevalence rates quoted in these studies have varied from 0.458 to 23.69 per 100,000 people.
More recent prevalence rates of 1:10,000 to 1:20,000 for men and 1:30,000 to 1:50,000 for women have been reported.
In addition, another recent study calculated an overall metaanalytical prevalence for transsexualism of 4.6 in 100,000 people (6.8 for transwomen and 2.6 for transmen).
然后是自闭症谱系(ASD)在全人群、患者性别比,以及各性别中的患病率统计:
Autism spectrum disorder has a prevalence of 20.6:10,000, with a male/female ratio of 4.2/1, although arecent report has suggested that rates could be as high as 1 in 50 for men and 1 in 150 for women.
随后,经过对19篇独立研究的原始数据进行一系列数学统计分析:
首先与其它的研究相比,这19篇研究得出的自闭症谱系(ASD)与性别焦虑(GD)的发生率都较高,可能是因为非针对性的研究有较高的假阴性,在全人群筛查中容易漏过可能的样本,也不能排除研究设计对诊断量表的选择本身导致了更高的阳性率。
The study also found that the prevalence of ASD in all assessed adolescents was 9.4% (n ¼ 9), 6.5% in those with GID (n ¼ 5), and 37.5% (n ¼ 3) for those with GID NOS. The study concluded that the combined prevalence of ASD within the combined sample was 7.8% (n ¼ 16), 4.7% (n ¼ 6) in those with GID, and 17.0% (n ¼ 9) in GID NOS. This is significantly higher than the prevalence of ASD in the general population as previously reported.
在分析了这些偏移后,本篇文章最终得出结果:
在自闭症谱系(ASD)儿童和青少年中,性别焦虑(GD)的发生率高于一般人群。
Robust studies conducted in this area suggest that the prevalence rates of ASD in children and adolescents with symptoms of gender dysphoria are considerably higher than in the general population.
在性别焦虑(GD)的成年人中,大多数其中研究发现,自闭症谱系(ASD)倾向(Autism Spectrum Quotient, AQ)明显高于一般人群,尤其是在Transman以及Trans Lesbian之中。
Jones et al found that transmen scored significantly higher on the AQ than transwomen and control women. The AQ was significantly higher for all trans people compared with the general population. The study also found that homosexual transwomen had significantly higher AQ levels than heterosexual transwomen.
从本篇Meta分析保守地得出的结果来看:
自闭症谱系(ASD)中的性别焦虑(GD)发生率,高于全人群中的性别焦虑(GD)的发生率。
关于出现这种现象的机制,这篇Meta分析中也做了一些讨论:
包括一些研究认为ASD的发生与中性化的激素水平有关等等。
They found that women diagnosed with ASD had increased serum testosterone levels and displayed more masculine traits than women without ASD. In addition, men with ASD displayed more feminine characteristics than men without ASD. They concluded that rather than being a disorder characterized by masculinization in men and women, ASD seems to be a gender defiant disorder and therefore gender incongruence should be expected in patients with ASD.
不过这篇文章还提出了一个重要的问题,那就是几乎所有相关研究都来自于儿童精神科发达的西北欧与北美地区,儿童期确诊自闭症谱系(ASD)后,患者日后的就诊率和医生对患者情况的关注度都会提升,可能导致自闭症谱系(ASD)中性别焦虑(GD)更容易被发现,而一般人群中的性别焦虑(GD)发生率很可能因为就诊率而被低估了,此外自闭症谱系(ASD)诊断性别焦虑(GD)后,对后续转归情况的跟踪随访与统计资料存在不足,也可能存在自闭症谱系中性别焦虑确定诊断数量被高估的情况。
在脑网络角度,还找到了一篇文章(参考文献[2])涉及自闭症谱系中高性别焦虑比例的机制问题:
在近几年的研究中逐渐发现自闭症谱系(ASD)相关症状出现的一个关键机制:
自闭症谱系(ASD)中,由于各种遗传和早期环境因素,导致生命早期(胎儿、婴儿、儿童前期)出现突触的过度生长,自闭症谱系(ASD)大脑中皮层间短程连接明显的多于长程连接,很多长程连接由于已经存在过多的短程连接而无法形成。长程连接的缺乏,是导致自闭症谱系(ASD)中很多症状出现的关键因素。[3]
在这篇文章中,通过研究一些自闭症谱系(ASD)视觉想象相关的功能,发现:长程连接的形成可能,可能导致自闭症谱系(ASD)中缺乏一些性别特征性的脑网络连接,使自闭症谱系(ASD)的一些特征趋于中性化。
综上,目前已经有足够的证据支持自闭症谱系(ASD)中的性别焦虑(GD)发生率较高,并能够从激素水平、脑网络等角度解释自闭症谱系(ASD)与性别焦虑(GD)在生物学机制上的相关性。
但是总体上,这个方向上的研究仍然较少,相对于自闭症谱系(ASD)整体的研究情况,这个方向上尤其缺少涉及到细胞学一下层次的研究。
相关回答
参考文献
[1] Glidden D, Bouman W P, Jones B A, et al. Gender dysphoria and autism spectrum disorder: A systematic review of the literature[J]. Sexual Medicine Reviews, 2016, 4(1): 3-14.
[2] Beacher F D C C, Radulescu E, Minati L, et al. Sex differences and autism: brain function during verbal fluency and mental rotation[J]. PloS one, 2012, 7(6): e38355.
[3] シナプス剪定の欠如は、自閉症スペクトラム障害患者の精神的健康状態にどうな影響をしますか?に対するYaakov Mikhael Liuさんの回答