Dietsche Bruno, Kircher Tilo, Falkenberg Irina
Department of Psychiatry and Psychotherapy, Philipps-Universität Marburg, Marburg, Germany.
Aust N Z J Psychiatry. 2017 May;51(5):500-508. doi: 10.1177/0004867417699473. Epub 2017 Mar 21.
Schizophrenia is a devastating mental disorder accompanied by aberrant structural brain connectivity. The question whether schizophrenia is a progressive brain disorder is yet to be resolved. Thus, it is not clear when these structural alterations occur and how they develop over time.
In our selective review, we summarized recent findings from longitudinal magnetic resonance imaging studies investigating structural brain alterations and its impact on clinical outcome at different stages of the illness: (1) subjects at ultra-high risk of developing psychosis, (2) patients with a first episode psychosis, and (3) chronically ill patients. Moreover, we reviewed studies examining the longitudinal effects of medication on brain structure in patients with schizophrenia.
(1) Studies from pre-clinical stages to conversion showed a more pronounced cortical gray matter loss (i.e. superior temporal and inferior frontal regions) in those individuals who later made transition to psychosis. (2) Studies investigating patients with a first episode psychosis revealed a decline in multiple gray matter regions (i.e. frontal regions and thalamus) over time as well as progressive cortical thinning in the superior and inferior frontal cortex. (3) Studies focusing on patients with chronic schizophrenia showed that gray matter decreased to a greater extent (i.e. frontal and temporal areas, thalamus, and cingulate cortices)-especially in poor-outcome patients. Very few studies reported effects on white matter microstructure in the longitudinal course of the illness.
There is adequate evidence to suggest that schizophrenia is associated with progressive gray matter abnormalities particularly during the initial stages of illness. However, causal relationships between structural changes and illness course-especially in chronically ill patients-should be interpreted with caution. Findings might be confounded by longer periods of treatment and higher doses of antipsychotics or epiphenomena related to the illness.
精神分裂症是一种具有破坏性的精神障碍，伴有大脑结构连接异常。精神分裂症是否为一种进行性脑部疾病的问题尚未得到解决。因此，目前尚不清楚这些结构改变何时发生以及它们如何随时间发展。
在我们的选择性综述中，我们总结了近期纵向磁共振成像研究的结果，这些研究调查了疾病不同阶段大脑结构改变及其对临床结局的影响：（1）有超高精神病发病风险的受试者，（2）首次发作精神病患者，以及（3）慢性病患者。此外，我们还综述了研究药物对精神分裂症患者脑结构纵向影响的研究。
（1）从临床前期到疾病转化阶段的研究表明，那些后来转变为精神病的个体皮质灰质损失更为明显（即颞上叶和额下回区域）。（2）对首次发作精神病患者的研究显示，多个灰质区域（即额叶区域和丘脑）随时间下降，以及额上回和额下回皮质逐渐变薄。（3）关注慢性精神分裂症患者的研究表明，灰质减少程度更大（即额叶和颞叶区域、丘脑和扣带回皮质）——尤其是在预后较差的患者中。在疾病的纵向过程中，很少有研究报道对白质微观结构的影响。
有充分证据表明，精神分裂症与进行性灰质异常有关，尤其是在疾病的初始阶段。然而，结构变化与病程之间的因果关系——尤其是在慢性病患者中——应谨慎解释。研究结果可能会因治疗时间较长、抗精神病药物剂量较高或与疾病相关的副现象而混淆。
