van der Velde Jorien, Gromann Paula M, Swart Marte, de Haan Lieuwe, Wiersma Durk, Bruggeman Richard, Krabbendam Lydia, Aleman André
Neuroimaging Center, University of Groningen, University Medical Center Groningen; Hanze University of Applied Sciences Groningen, Academy of Social studies, Groningen, The Netherlands.
Department of Educational Neuroscience, Faculty of Psychology and Education, VU University Amsterdam, Amsterdam, The Netherlands.
J Psychiatry Neurosci. 2015 May;40(3):207-13. doi: 10.1503/jpn.140064.
Grey matter, both volume and concentration, has been proposed as an endophenotype for schizophrenia given a number of reports of grey matter abnormalities in relatives of patients with schizophrenia. However, previous studies on grey matter abnormalities in relatives have produced inconsistent results. The aim of the present study was to examine grey matter differences between controls and siblings of patients with schizophrenia and to examine whether the age, genetic loading or subclinical psychotic symptoms of selected individuals could explain the previously reported inconsistencies.
We compared the grey matter volume and grey matter concentration of healthy siblings of patients with schizophrenia and healthy controls matched for age, sex and education using voxel-based morphometry (VBM). Furthermore, we selected subsamples based on age (< 30 yr), genetic loading and subclinical psychotic symptoms to examine whether this would lead to different results.
We included 89 siblings and 69 controls in our study. The results showed that siblings and controls did not differ significantly on grey matter volume or concentration. Furthermore, specifically selecting participants based on age, genetic loading or subclinical psychotic symptoms did not alter these findings.
The main limitation was that subdividing the sample resulted in smaller samples for the subanalyses. Furthermore, we used MRI data from 2 different scanner sites.
These results indicate that grey matter measured through VBM might not be a suitable endophenotype for schizophrenia.
鉴于多项关于精神分裂症患者亲属灰质异常的报道，灰质的体积和浓度已被提议作为精神分裂症的一种内表型。然而，先前关于亲属灰质异常的研究结果并不一致。本研究的目的是检查精神分裂症患者的对照者与兄弟姐妹之间的灰质差异，并检查所选个体的年龄、遗传负荷或亚临床精神病症状是否可以解释先前报道的不一致性。
我们使用基于体素的形态测量法（VBM）比较了精神分裂症患者的健康兄弟姐妹与年龄、性别和教育程度相匹配的健康对照者的灰质体积和灰质浓度。此外，我们根据年龄（<30岁）、遗传负荷和亚临床精神病症状选择了子样本，以检查这是否会导致不同的结果。
我们的研究纳入了89名兄弟姐妹和69名对照者。结果表明，兄弟姐妹与对照者在灰质体积或浓度上没有显著差异。此外，根据年龄、遗传负荷或亚临床精神病症状专门选择参与者并没有改变这些结果。
主要局限性在于对样本进行细分会导致亚分析的样本量较小。此外，我们使用了来自2个不同扫描站点的MRI数据。
这些结果表明，通过VBM测量的灰质可能不是精神分裂症合适的内表型。
