Department of Psychiatric Research, Diakonhjemmet Hospital, Oslo, Norway.
NORMENT, Institute of Clinical Medicine, University of Oslo, Oslo, Norway.
Psychol Med. 2022 Apr;52(6):1050-1059. doi: 10.1017/S0033291720002779. Epub 2020 Aug 10.
Uncertainty exists about what causes brain structure alterations associated with schizophrenia (SZ) and bipolar disorder (BD). Whether a history of asphyxia-related obstetric complication (ASP) - a common but harmful condition for neural tissue - contributes to variations in adult brain structure is unclear. We investigated ASP and its relationship to intracranial (ICV), global brain volumes and regional cortical and subcortical structures.
A total of 311 patients on the SZ - BD spectrum and 218 healthy control (HC) participants underwent structural magnetic resonance imaging. They were evaluated for ASP using prospective information obtained from the Medical Birth Registry of Norway.
In all groups, ASP was related to smaller ICV, total brain, white and gray matter volumes and total surface area, but not to cortical thickness. Smaller cortical surface areas were found across frontal, parietal, occipital, temporal and insular regions. Smaller hippocampal, amygdala, thalamus, caudate and putamen volumes were reported for all ASP subgroups. ASP effects did not survive ICV correction, except in the caudate, which remained significantly smaller in both patient ASP subgroups, but not in the HC.
Since ASP was associated with smaller brain volumes in all groups, the genetic risk of developing a severe mental illness, alone, cannot easily explain the smaller ICV. Only the smaller caudate volumes of ASP patients specifically suggest that injury from ASP can be related to disease development. Our findings give support for the ICV as a marker of aberrant neurodevelopment and ASP in the etiology of brain development in BD and SZ.
精神分裂症（SZ）和双相情感障碍（BD）相关的脑结构改变的原因尚不确定。与窒息相关的产科并发症（ASP）——一种对神经组织有害的常见情况——是否会导致成人脑结构的变化尚不清楚。我们研究了 ASP 及其与颅内（ICV）、全脑体积以及皮质和皮质下结构的关系。
共有 311 名 SZ-BD 谱系患者和 218 名健康对照（HC）参与者接受了结构磁共振成像检查。他们通过挪威医学出生登记处获得的前瞻性信息，对 ASP 进行了评估。
在所有组中，ASP 与 ICV、全脑、白质和灰质体积以及总表面积较小有关，但与皮质厚度无关。在前额、顶叶、枕叶、颞叶和岛叶等区域均发现皮质表面积较小。所有 ASP 亚组的海马体、杏仁核、丘脑、尾状核和壳核体积均较小。除尾状核外，所有 ASP 亚组的 ICV 校正后 ASP 效应均不显著，尾状核体积在患者 ASP 亚组中均较小，但在 HC 中则无差异。
由于 ASP 与所有组的脑体积较小有关，因此，仅严重精神疾病的遗传风险并不能轻易解释 ICV 较小的原因。只有 ASP 患者的尾状核体积较小，这表明 ASP 引起的损伤可能与疾病的发展有关。我们的研究结果为 ICV 作为神经发育异常的标志物以及 ASP 在 BD 和 SZ 脑发育病因学中的作用提供了支持。
