失眠障碍患者记忆功能与海马结构及功能影像的相关性

Relationship among memory function, hippocampal structure and functional imaging in patients with insomnia disorder

目的探讨失眠障碍患者记忆功能以及海马结构、功能影像之间的关系。方法收集22例失眠障碍患者(研究组)和17例正常对照者(对照组)。采用匹兹堡睡眠质量指数量表(PSQI)、埃普沃思嗜睡量表(ESS)、失眠严重程度指数量表(ISI)评估两组睡眠质量。采用蒙特利尔认知评估量表(MoCA)和九盒迷宫试验评估两组的认知及记忆功能。所有受试者行颅脑磁共振常规扫描,计算标准海马体积,同时利用弥散张量成像技术,工作站自动生成各向异性指数图(FA图)及表观弥散系数图(ADC图),计算受试者的FA值和ADC值。结果研究组物体工作记忆、空间工作记忆均表现较差(P<0.05)。研究组左、右侧及总海马标准化体积均小于对照组(P<0.01)。标准化左侧及总海马体积与空间工作记忆错误数呈负相关(P<0.05)。研究组所有患者病程均超过10年,标准化左、右两侧体积及总海马体积均与病程呈负相关(P<0.01)。研究组海马FA值小于对照组(P<0.05),ADC值大于对照组(P<0.05)。研究组FA值与空间参考记忆、空间工作记忆呈负相关(P<0.05)。ADC值与空间工作记忆功能呈正相关(P<0.05)。结论失眠障碍患者的整体睡眠质量下降,日间功能受损,物体以及空间记忆功能降低,海马体积缩小,海马白质纤维结构损害明显。患者病程越长,体积萎缩越明显。空间记忆能力下降与白质纤维损害及海马体积萎缩相关联。

Objective To explore the relationship among memory function,hippocampal structure,functional imaging in patients with insomnia disorder.Methods 22 patients with insomnia disorder in study group and 17 healthy controls in control group were selected and assessed with Pittsburgh Sleep Quality Index(PSQI),Epworth Sleepiness Scale(ESS),Insomnia Severity Index(ISI),Montreal Cognitive Assessment(MoCA)and Nine-box Maze.All the subjects underwent brain magnetic resonance imaging(MRI)to calculate the standard hippocampal volume and their FA and ADC values were calculated through Diffusion Tensor Imaging(DTI)technique,workstation automatically generates fractional anisotropy(FA)and apparent diffusion coefficient(ADC)maps.Results In terms of object working memory and spatial working memory,subjects in study group performed worse than those in control group(P<0.05).The volumes of left,right and total hippocampus in study group were all significantly smaller than those in control group(P<0.01).Negative correlations were observed between standard left,whole hippocampal volumes with error numbers in spatial working memory(P<0.05).The courses of disease in all patients in study group were over 10 years.Negative correlations were observed between standard left,right and whole hippocampal volumes with the course of disease respectively(P<0.05).The FA value in study group was significantly lower than that in control group(P<0.05).The ADC value in study group was significantly higher than that in control group(P<0.05).In study group,the FA value was negatively correlated with spatial reference memory and spatial working memory(P<0.05);and the ADC value was positively correlated with spatial working memory(P<0.05).Conclusion There are bad sleep quality,daytime function impairment,worse object and spatial memory functions,smaller hippocampal volume and obvious damage in hippocampal white matter fibers structure in patients with insomnia disorder.The hippocampal volume shrinks more obviously with longer course of disease.The worse spatial memory function is correlated with white matter fibers damage and hippocampal volume shrink.