脑萎缩对皮质下缺血性血管病患者认知功能的影响

Effect of brain atrophy on the cognition in patients with subcortical ischemic vascular disease

目的探讨脑萎缩对皮质下缺血性血管病（SIVD）患者认知功能的影响。方法选取2013年9月至2014年12月在安徽医科大学第一附属医院神经内科门诊或住院的SIVD患者116例，根据诊断标准分为SIVD无认知损害组（SIVD—NCI）、SIVD轻度认知损害组（SIVD—MCI）和SIVD痴呆组（SIVD—VaD）；采用多种神经心理学量表包括简易智能精神状态量表（MMSE）、剑桥老年认知功能评估量表．中文版（CAMCOG—C）等进行评估；使用3．0T头颅MRI扫描，按照视觉等级评分量表分别对额叶、颞叶、顶叶萎缩程度评分（0～3分），同时分别评定额区、顶枕区、颞区、基底节区脑白质疏松（LA）程度及腔隙性脑梗死（u）数目。比较各组问不同脑叶萎缩程度、LA程度、LI数目，并将认知功能评分与其及血管危险因素进行二元Logistic回归分析。结果（1）SIVD—MCI组和SIVD—VaD组萎缩评分、额叶萎缩评分、LA评分及LI数目均显著高于SIVD—NCI组，差异均有统计学意义（H=6．138，P=0．013；H=45．845，P=0．000；H=36．818，P=0．000；H=37．46，P=0．000），SIVD—NCI组和SIVD—MCI组颞叶萎缩评分差异无统计学意义，顶叶萎缩三组间差异无统计学意义；（2）相关分析发现，萎缩评分、LA评分及lJI数目与SIVD认知功能呈负相关，其中额叶萎缩评分、顶枕区LA评分及基底节区LI数目与MMSE、CAMCOG—C及其部分子项呈显著负相关（均P〈0．05），颞区LI数目与MMSE、CAMCOG—C及其各子项评分均无显著相关（均P〉0．05）；（3）回归分析发现，控制性别、年龄、受教育年限及血管危险因素等因素后，受教育年限（OR=0．787，P=0．009）、LA评分（OR=1．201，P=0．036）和LI数目（OR=1．221，P=0．011）与认知功能相关，校正萎缩后，LA评分与认知功能间的关系并不显著，萎缩、LI及受教育年限仍与认知功能相关，其中额叶萎缩与认知功能显著相关（OR=16．082，P=0．000），颞叶和顶叶萎缩与认知功能无显著相关。结论脑萎缩可能为SIVD患者认知损害新的独立的预测指标，且脑萎缩、LI数目、LA程度在认知损害中的作用可能依次减小。

Objective To explore the effect of brain atrophy on the cognition in patients with subcortical ischemic vascular disease （SIVD）. Methods A total of 116 SIVD patients were enrolled from the Department of Neurology, First Affiliated Hospital, Anhui Medical University between September 2013 and December 2014. Lobar atrophy, leukoaraiosis （LA）, lacunar infarcts （LI） and vascular risk factors were analyzed in the 116 SIVD patients who were divided into three groups according to the diagnostic criteria： non-cognitive impairment group （SIVD-NCI） , mild cognitive impairment group （SIVD-MCI） and dement group （ SIVD-VaD ）. All patients underwent magnetic resonance imaging （ MRI ） with a 3. 0-T system. The cognitive functions were evaluated by mini-metal state examination （MMSE） , the Cambridge cognitive examination-Chinese version （CAMCOG-C） , etc. A widely used visual atrophy rating method （0 to 3 ） was adopted to rate the severity of frontal, parietal and temporal lobe atrophy. The degree of LA and the numbers of LI in 4 brain regions （ frontal, parieto-occipital, temporal, and basal ganglia） were evaluated meanwhile. Results Firstly, both the SIVD-MCI and SIVD-VaD groups showed significantly higher total scores of atrophy, higher frontal lobe atrophy scores, higher LA scores and larger LI numbers than SIVD-NCI （H=6.138, P=0.013; H=45.845, P =0.000; H=36. 818, P=0.000; H-37.46, P =0.000）. There were no significant differences in temporal lobe atrophy scores between SIVD-NCI group and SIVD- MCI group. Parietal lobe atrophy scores also showed no differences among the three groups. Secondly, as well as total numbers of LI, total scores of atrophy and LA were negatively correlated with SIVD cognition, especially frontal lobe atrophy scores, parieto-occipital LA scores and basal ganglia LI numbers had a remarkable negative correlation with MMSE scores, CAMCOG-C scores and partial subitems in CAMCOG-C scores （P 〈 0. 005 ）. However temporal LI numbers was absence of correlation with MMSE scores, CAMCOG-C scores and subitems in CAMCOG-C scores （P 〉 0. 005）. Thirdly, education （ OR = 0. 787, P=0.009）, total scores of LA （OR= 1.201, P=0.036） and total numbers of LI （OR= 1.221, P= 0. 011 ） remained to be associated with cognition after controlling for sex, age, education, hypertension, diabetes, smoking. While, after adjusting atrophy scores, total scores of LA had no significant association with cognition. Atrophy scores, total numbers of LI and education still showed significant association with cognition, particularly frontal lobe atrophy scores （ OR = 16. 082, P = 0. 000）, but not temporal and parietal lobe atrophy scores. Conclusions Brain atrophy may be a new and independent predictive index of cognitive impairment in SIVD. Further, the effect of brain atrophy, the numbers of LI and degree of LA on cognitive decline is independent and decreases in turn.