van Duinkerken Eelco, Ijzerman Richard G, Klein Martin, Moll Annette C, Snoek Frank J, Scheltens Philip, Pouwels Petra J W, Barkhof Frederik, Diamant Michaela, Tijms Betty M
Diabetes Center/Department of Internal Medicine, VU University Medical Center, Amsterdam, The Netherlands.
Department of Medical Psychology, VU University Medical Center, Amsterdam, The Netherlands.
Hum Brain Mapp. 2016 Mar;37(3):1194-208. doi: 10.1002/hbm.23096. Epub 2015 Dec 23.
Type 1 diabetes mellitus (T1DM) patients, especially with concomitant microvascular disease, such as proliferative retinopathy, have an increased risk of cognitive deficits. Local cortical gray matter volume reductions only partially explain these cognitive dysfunctions, possibly because volume reductions do not take into account the complex connectivity structure of the brain. This study aimed to identify gray matter network alterations in relation to cognition in T1DM.
We investigated if subject-specific structural gray matter network properties, constructed from T1-weighted MRI scans, were different between T1DM patients with (n = 51) and without (n = 53) proliferative retinopathy versus controls (n = 49), and were associated to cognitive decrements and fractional anisotropy, as measured by voxel-based TBSS. Global normalized and local (45 bilateral anatomical regions) clustering coefficient and path length were assessed. These network properties measure how the organization of connections in a network differs from that of randomly connected networks.
Global gray matter network topology was more randomly organized in both T1DM patient groups versus controls, with the largest effects seen in patients with proliferative retinopathy. Lower local path length values were widely distributed throughout the brain. Lower local clustering was observed in the middle frontal, postcentral, and occipital areas. Complex network topology explained up to 20% of the variance of cognitive decrements, beyond other predictors. Exploratory analyses showed that lower fractional anisotropy was associated with a more random gray matter network organization.
T1DM and proliferative retinopathy affect cortical network organization that may consequently contribute to clinically relevant changes in cognitive functioning in these patients.
1型糖尿病（T1DM）患者，尤其是伴有微血管疾病（如增殖性视网膜病变）的患者，认知缺陷风险增加。局部皮质灰质体积减少只能部分解释这些认知功能障碍，可能是因为体积减少未考虑大脑复杂的连接结构。本研究旨在确定T1DM中与认知相关的灰质网络改变。
我们研究了由T1加权MRI扫描构建的个体特异性结构灰质网络属性在伴有（n = 51）和不伴有（n = 53）增殖性视网膜病变的T1DM患者与对照组（n = 49）之间是否存在差异，并与认知减退和分数各向异性相关，分数各向异性通过基于体素的TBSS测量。评估了全局归一化和局部（45个双侧解剖区域）聚类系数及路径长度。这些网络属性衡量网络中连接的组织与随机连接网络的组织有何不同。
与对照组相比，两个T1DM患者组的全局灰质网络拓扑结构更随机，在增殖性视网膜病变患者中影响最大。较低的局部路径长度值广泛分布于整个大脑。在额中回、中央后回和枕叶区域观察到较低的局部聚类。复杂网络拓扑结构解释了认知减退方差的20%，超过其他预测因素。探索性分析表明，较低的分数各向异性与更随机的灰质网络组织相关。
T1DM和增殖性视网膜病变会影响皮质网络组织，进而可能导致这些患者认知功能出现临床相关变化。
