脑白质微结构完整性与高血压患者认知功能的相关性

Correlation between white matter microstructural integrity and cognitive function in patients with hypertension

目的利用纤维束自动定量法探讨高血压对脑白质微结构的影响及其与认知功能的相关性。方法连续性收集2017年1月至2018年7月于南京大学医学院附属鼓楼医院就诊的受试者,分为不伴认知损害的高血压组(hypertension without cognitive impairment,HTN-nonCI;n=44)、伴认知损害的高血压组(hypertension with cognitive impairment,HTN-CI;n=50)及对照组(n=25)。收集受试者影像学资料及神经心理学量表测试结果,采用纤维束自动定量法得到全脑20条纤维束上各100个节点的弥散参数,比较对照组与HTN-nonCI组以及HTN-nonCI与HTN-CI组各纤维束弥散参数的差异性节段,对HTN-nonCI组与HTN-CI组具有显著差异的脑白质纤维束与各认知域进行相关性分析。结果三组脑白质纤维束的各向异性分数(fractional anisotropy,FA)均呈递减趋势,平均扩散系数(mean diffusivity,MD)均呈递增趋势。对对照组与HTN-nonCI组进行的比较显示,左侧丘脑放射束中点偏脑干侧、胼胝体膝部近脑干侧、胼胝体压部额部及近侧脑室处的FA值差异有统计学意义(P均<0.05);左侧丘脑放射束中部及近脑干部、右侧丘脑放射束近脑干部、左侧皮质脊髓束顶部及近脑干部、右侧扣带束海马中部、胼胝体膝部中部、胼胝体压部近侧脑室处、左侧钩束近额部的MD值差异有统计学意义(P均<0.05)。对HTN-nonCI组与HTN-CI组进行的比较显示,左侧扣带束扣带回的散在分布节段和左侧下额枕束近枕叶侧的FA值差异有统计学意义,其中左侧扣带束扣带回与蒙特利尔认知评估量表评分显著相关(标化β=0.268,P=0.029);右侧丘脑放射束近脑干部、胼胝体压部额部及近侧脑室处、右侧下纵束的散在分布节段的MD值差异有统计学意义,其中右侧下纵束与记忆力(标化β=-0.243,P=0.047)及执行功能(标化β=-0.284,P=0.021)显著相关。结论高血压患者普遍存在脑白质微结构完整性破坏,但部分节段更易受高血压影响。扣带束扣带回完整性与整体认知功能显著相关,下纵束完整性与执行功能及记忆力显著相关。

Objective To investigate the effect of hypertension on white matter microstructure and its correlation with cognitive function using automated fiber-tract quantification.Methods Consecutive subjects visited Drum Tower Hospital,the Affiliated Hospital of Nanjing University Medical School between January 2017 and July 2018 were collected.They were divided into hypertension without cognitive impairment(HTN-nonCI)group(n=44),hypertension with cognitive impairment(HTN-CI)group(n=50),and control group(n=25).The imaging data and neuropsychological scale test results of the subjects were collected.The automated fiber-tract quantification was used to obtain the diffusion parameters of 100 nodes on 20 fiber tracts in the whole brain.The differential segments of each fiber tract diffusion parameter between the control group and HTN-nonCI group,and the HTN-nonCI group and HTN-CI group were compared.Correlation analysis was performed in white matter fiber tracts with significant differences and each cognitive domain between the HTN-nonCI group and the HTN-CI group.Results The fractional anisotropy(FA)of white matter fiber tracts in 3 groups showed a decreasing trend,and the mean diffusion diffusivity(MD)showed an increasing trend.The comparison between the control group and the HTN-nonCI group showed that there were significant differences in the FA values of the midpoint of left thalamic radiation tract partial to brainstem,the genus of corpus callosum near brainstem,and frontal part and and proximal ventricle of splenium of corpus callosum(all P<0.05);there were significant differences in the MD values of the middle part of left thalamic radiation tract and near the brainstem,the right thalamic radiation tract near the brainstem,the top of left corticospinal tract and near brainstem,the middle hippocampus of right cingulate tract,the middle part of genu of corpus callosum,the splenium of the corpus callosum near the lateral ventricle,the left uncinate tract near the forehead(all P<0.05).A comparison between the HTN-nonCI group and the HTN-CI group showed that there was significant difference in the FA value between the distributed segments of cingulate gyrus of left cingulate tract and the left inferior fronto-occipital tract near the occipital lobe,in which cingulate gyrus of left cingulate tract was significantly correlated with the Montreal Cognitive Assessment Scale score(standardizedβ=0.268,P=0.029);there were significant differences in the right thalamic radiation tract near the brainstem,the forehead and proximal ventricle of splenium of the corpus callosum,and the scattered distribution segments of the right inferior longitudinal fasciculus,in which the right inferior longitudinal fasciculus was significantly correlated with memory(standardizedβ=-0.243,P=0.047)and executive function(standardizedβ=-0.284,P=0.021).Conclusions Microstructural integrity of white matter was generally destroyed in patients with hypertension,but some segments were more susceptible to hypertension.The integrity of cingulate gyrus of cingulate tract was significantly correlated with the overall cognitive function.The integrity of inferior longitudinal fasciculus was significantly correlated with the executive function and memory.