1 Melbourne Neuropsychiatry Centre, Department of Psychiatry, The University of Melbourne, Carlton South, VIC, Australia.
2 Orygen, The National Centre of Excellence in Youth Mental Health, Parkville, VIC, Australia.
Aust N Z J Psychiatry. 2018 Sep;52(9):864-875. doi: 10.1177/0004867418775833. Epub 2018 May 27.
Schizophrenia is increasingly conceived as a disorder of brain network connectivity and organization. However, reports of network abnormalities during the early illness stage of psychosis are mixed. This study adopted a data-driven whole-brain approach to investigate functional connectivity and network architecture in a first-episode psychosis cohort relative to healthy controls and whether functional network properties changed abnormally over a 12-month period in first-episode psychosis.
Resting-state functional connectivity was performed at two time points. At baseline, 29 first-episode psychosis individuals and 30 healthy controls were assessed, and at 12 months, 14 first-episode psychosis individuals and 20 healthy controls completed follow-up. Whole-brain resting-state functional connectivity networks were mapped for each individual and analyzed using graph theory to investigate whether network abnormalities associated with first-episode psychosis were evident and whether functional network properties changed abnormally over 12 months relative to controls.
This study found no evidence of abnormal resting-state functional connectivity or topology in first-episode psychosis individuals relative to healthy controls at baseline or at 12-months follow-up. Furthermore, longitudinal changes in network properties over a 12-month period did not significantly differ between first-episode psychosis individuals and healthy control. Network measures did not significantly correlate with symptomatology, duration of illness or antipsychotic medication.
This is the first study to show unaffected resting-state functional connectivity and topology in the early psychosis stage of illness. In light of previous literature, this suggests that a subgroup of first-episode psychosis individuals who have a neurotypical resting-state functional connectivity and topology may exist. Our preliminary longitudinal analyses indicate that there also does not appear to be deterioration in these network properties over a 12-month period. Future research in a larger sample is necessary to confirm our longitudinal findings.
精神分裂症越来越被认为是一种大脑网络连接和组织的障碍。然而，关于精神病早期阶段网络异常的报告却存在差异。本研究采用数据驱动的全脑方法，研究首发精神病患者与健康对照组的功能连接和网络结构，以及首发精神病患者在 12 个月内功能网络特性是否异常变化。
在两个时间点进行静息态功能连接。在基线时，评估了 29 名首发精神病患者和 30 名健康对照者，在 12 个月时，14 名首发精神病患者和 20 名健康对照者完成了随访。对每个个体进行全脑静息态功能连接网络映射，并使用图论进行分析，以调查与首发精神病相关的网络异常是否明显，以及功能网络特性是否在 12 个月内相对于对照组异常变化。
本研究在基线或 12 个月随访时，均未发现首发精神病患者的静息态功能连接或拓扑结构存在异常。此外，12 个月内网络特性的纵向变化在首发精神病患者和健康对照组之间没有显著差异。网络测量与症状、疾病持续时间或抗精神病药物无显著相关性。
这是第一项表明在疾病早期阶段首发精神病患者的静息态功能连接和拓扑结构未受影响的研究。鉴于之前的文献，这表明存在一个具有神经典型静息态功能连接和拓扑结构的首发精神病患者亚组。我们初步的纵向分析表明，在 12 个月内这些网络特性似乎也没有恶化。未来需要在更大的样本中进行研究，以确认我们的纵向发现。
