García-Casares Natalia, Berthier Marcelo L, Jorge Ricardo E, Gonzalez-Alegre Pedro, Gutiérrez Cardo Antonio, Rioja Villodres José, Acion Laura, Ariza Corbo María José, Nabrozidis Alejandro, García-Arnés Juan A, González-Santos Pedro
Department of Medicine, Faculty of Medicine, University of Malaga, Spain Centro de Investigaciones Médico-Sanitarias (C.I.M.E.S), Malaga, Spain.
Department of Psychiatry, Iowa City Veterans Administration Medical Center, The University of Iowa, West Iowa City, IA, USA.
J Alzheimers Dis. 2014;40(2):375-86. doi: 10.3233/JAD-131736.
Type 2 diabetes mellitus (T2DM) is an emerging risk factor for cognitive impairment. Whether this impairment is a direct effect of this metabolic disorder on brain function, a consequence of vascular disease, or both, remains unknown. Structural and functional neuroimaging studies in patients with T2DM could help to elucidate this question.
We designed a cross-sectional study comparing 25 T2DM patients with 25 age- and gender-matched healthy control participants. Clinical information, APOE genotype, lipid and glucose analysis, structural cerebral magnetic resonance imaging including voxel-based morphometry, and F-18 fluorodeoxyglucose positron emission tomography were obtained in all subjects.
Gray matter densities and metabolic differences between groups were analyzed using statistical parametric mapping. In addition to comparing the neuroimaging profiles of both groups, we correlated neuroimaging findings with HbA1c levels, duration of T2DM, and insulin resistance measurement (HOMA-IR) in the diabetic patients group.
Patients with T2DM presented reduced gray matter densities and reduced cerebral glucose metabolism in several fronto-temporal brain regions after controlling for various vascular risk factors. Furthermore, within the T2DM group, longer disease duration, and higher HbA1c levels and HOMA-IR were associated with lower gray matter density and reduced cerebral glucose metabolism in fronto-temporal regions.
In agreement with previous reports, our findings indicate that T2DM leads to structural and metabolic abnormalities in fronto-temporal areas. Furthermore, they suggest that these abnormalities are not entirely explained by the role of T2DM as a cardiovascular risk factor.
2型糖尿病（T2DM）是认知障碍的一个新出现的危险因素。这种障碍是这种代谢紊乱对脑功能的直接影响、血管疾病的后果，还是两者兼而有之，仍不清楚。对T2DM患者进行的结构和功能神经影像学研究有助于阐明这个问题。
我们设计了一项横断面研究，比较25例T2DM患者与25例年龄和性别匹配的健康对照参与者。获取了所有受试者的临床信息、载脂蛋白E（APOE）基因型、脂质和葡萄糖分析、包括基于体素的形态测量的结构脑磁共振成像，以及F-18氟脱氧葡萄糖正电子发射断层扫描。
使用统计参数映射分析两组之间的灰质密度和代谢差异。除了比较两组的神经影像学特征外，我们还将糖尿病患者组的神经影像学结果与糖化血红蛋白（HbA1c）水平、T2DM病程和胰岛素抵抗测量值（稳态模型评估胰岛素抵抗，HOMA-IR）进行了相关性分析。
在控制了各种血管危险因素后，T2DM患者在几个额颞脑区的灰质密度降低，脑葡萄糖代谢减少。此外，在T2DM组中，病程较长、HbA1c水平和HOMA-IR较高与额颞区灰质密度较低和脑葡萄糖代谢减少有关。
与先前的报告一致，我们的研究结果表明T2DM会导致额颞区的结构和代谢异常。此外，这些异常并不能完全由T2DM作为心血管危险因素的作用来解释。
