IRCCS Santa Lucia Foundation, Rome, Italy.
Schizophr Res. 2011 Jan;125(1):30-40. doi: 10.1016/j.schres.2010.08.023. Epub 2010 Sep 25.
Suicide is a major cause of death in schizophrenia. Neurobiological studies suggest that suicidality is associated with abnormal brain structure and connectivity in fronto-temporo-limbic regions. However, it is still unclear whether suicidality in schizophrenia is related to volumetric abnormalities in subcortical structures that play a key role in emotion regulation, aggression and impulse control. Therefore, we aimed to examine whether the volume of selected subcortical regions is associated with previous suicidal attempts and self-aggression in schizophrenia. For this cross-sectional study, we recruited 50 outpatients with schizophrenia and 50 healthy controls (HC) matched for age and gender. Fourteen patients had a history of one or more suicide attempts. Different forms of aggression were assessed using the Modified Overt Aggression Scale. All participants underwent structural MR imaging at 3 Tesla. Physical volumetric measures were calculated for the lateral ventricles, thalamus, hippocampus, amygdala, caudate, putamen, pallidum and accumbens using an automatic segmentation method on T1-weighted high-resolution (voxel size 1×1×1mm(3)) images. Multivariate and follow-up univariate ANOVAs revealed a selective increase in volume in the right amygdala of patients with a history of suicidality compared both to patients without such a history and HC. Moreover, in the entire patient group increased right amygdala volume was related to increased self-aggression. Our findings suggest that right amygdala hypertrophy may be a risk factor for suicide attempts in patients with schizophrenia and this could be relevant for suicide prevention.
自杀是精神分裂症的主要死因之一。神经生物学研究表明，自杀意念与额颞叶边缘区域的大脑结构和连接异常有关。然而，目前尚不清楚精神分裂症患者的自杀意念是否与在情绪调节、攻击和冲动控制中起关键作用的皮质下结构的体积异常有关。因此，我们旨在研究选定的皮质下区域的体积是否与精神分裂症患者的既往自杀企图和自我攻击有关。在这项横断面研究中，我们招募了 50 名精神分裂症门诊患者和 50 名年龄和性别相匹配的健康对照者（HC）。14 名患者有一次或多次自杀企图的病史。使用改良显性攻击量表评估了不同形式的攻击行为。所有参与者均在 3 Tesla 磁共振成像仪上进行结构磁共振成像。使用基于 T1 加权高分辨率（体素大小为 1×1×1mm(3)）图像的自动分割方法，计算侧脑室、丘脑、海马、杏仁核、尾状核、壳核、苍白球和伏隔核的物理体积测量值。多变量和后续单变量方差分析显示，有自杀史的患者右侧杏仁核体积选择性增加，与无此病史的患者和 HC 相比均增加。此外，在整个患者组中，右侧杏仁核体积的增加与自我攻击的增加有关。我们的研究结果表明，右侧杏仁核肥大可能是精神分裂症患者自杀企图的危险因素，这可能与自杀预防有关。
