Moulton Calum D, Costafreda Sergi G, Horton Paul, Ismail Khalida, Fu Cynthia H Y
Department of Psychological Medicine, Institute of Psychiatry, King's College London, London, UK.
Division of Psychiatry, Faculty of Brain Sciences, University College London, London, UK.
Brain Imaging Behav. 2015 Dec;9(4):651-62. doi: 10.1007/s11682-014-9348-2.
Diabetes is associated with macrovascular and microvascular complications and is a major risk factor for neurological and psychiatric disorders, such as dementia and depression. Type 1 diabetes (T1DM) and type 2 diabetes (T2DM) have distinct etiologies and pathophysiological effects while sharing a common endpoint of persistent hyperglycemia. Neuroimaging studies in T1DM have revealed reductions in numerous regions, including the parahippocampal and occipital regions, while in T2DM there have been numerous reports of hippocampal atrophy. This meta-analysis aimed to identify consistent regional abnormalities in cerebral structures in T1DM and T2DM respectively, and also to examine the impact of potential confounds, including age, depression and vascular risk factors. Neuroimaging studies of both voxel-based morphometry (VBM) data and volumetric data were included. Ten T1DM studies (n = 613 patients) and 23 T2DM studies (n = 1364 patients) fulfilled inclusion criteria. The T1DM meta-analysis revealed reduced bilateral thalamus grey matter density in adults. The T2DM meta-analysis revealed reduced global brain volume and regional atrophy in the hippocampi, basal ganglia, and orbitofrontal and occipital lobes. Moreover, hippocampal atrophy in T2DM was not modified by hypertension, although there were more marked reductions in younger patients relative to healthy controls. In conclusion, T1DM and T2DM demonstrated distinct cerebral effects with generalised and specific target areas of grey matter reduction. Thalamic atrophy in T1DM may be a substrate of associated cognitive deficits. In T2DM, global cerebral atrophy may reflect atherosclerotic factors, while hippocampal atrophy was an independent effect providing a potential common neuropathological etiology for the comorbidity of T2DM with dementia and depression.
糖尿病与大血管和微血管并发症相关，是神经和精神疾病（如痴呆和抑郁症）的主要危险因素。1型糖尿病（T1DM）和2型糖尿病（T2DM）病因和病理生理效应不同，但都有持续性高血糖这一共同终点。T1DM的神经影像学研究显示多个区域体积减小，包括海马旁回和枕叶区域；而T2DM有大量海马萎缩的报道。这项荟萃分析旨在分别确定T1DM和T2DM脑结构中一致的区域异常，同时研究潜在混杂因素（包括年龄、抑郁和血管危险因素）的影响。纳入了基于体素的形态学测量（VBM）数据和体积数据的神经影像学研究。10项T1DM研究（n = 613例患者）和23项T2DM研究（n = 1364例患者）符合纳入标准。T1DM荟萃分析显示成人双侧丘脑灰质密度降低。T2DM荟萃分析显示全脑体积减小以及海马、基底神经节、眶额叶和枕叶区域萎缩。此外，T2DM患者的海马萎缩不受高血压影响，不过相对于健康对照，年轻患者的海马萎缩更明显。总之，T1DM和T2DM表现出不同的脑效应，有灰质减少的广泛性和特定目标区域。T1DM患者的丘脑萎缩可能是相关认知缺陷的基础。在T2DM中，全脑萎缩可能反映动脉粥样硬化因素，而海马萎缩是一种独立效应，为T2DM与痴呆和抑郁症共病提供了潜在的共同神经病理学病因。
