脑血管病变与阿尔茨海默病关系的病例对照研究

The case-control study on the relationship between cerebrovascular lesions and Alzheimer disease

目的探讨阿尔茨海默病与经头部CT证实的脑血管病变、白质病变的可能关系。方法选择60例阿尔茨海默病患者及84例年龄、性别与之相匹配的认知功能正常老年人,采用盲法分析临床诊断前3～5年的头部CT资料,调查头部CT显示的各种脑血管病变;对白质病变进行分区评分(评分等级为0～3分),并将双侧额区、顶枕区、颞区及幕下共8个区域的总和作为白质病变总评分;测量钩间距、双侧侧裂宽度、第三脑室宽度、哈氏值、脑室指数和侧脑室体部指数,以反映脑萎缩和脑室扩大的程度。结果CT资料显示,阿尔茨海默病组患者存在明显的脑血管病变、白质病变、脑萎缩和脑室系统扩大;正常对照组有脑血管病变者15例(17.86%),阿尔茨海默病组33例(55.00%),单因素分析组间差异有高度统计学意义(P=0.0001)。两组白质病变均以双侧额区和顶枕区评分居高,双侧颞区和幕下评分较低;白质病变总评分、双侧额区及左侧顶枕区白质病变评分,组间差异有统计学意义(P<0.05)。两组钩间距、双侧侧裂宽度、第三脑室宽度及侧脑室体部指数,组间差异亦有统计学意义(P<0.05);但哈氏值、脑室指数,组间差异无统计学意义(P>0.05)。多因素分析显示,考虑白质病变总评分时,脑血管病变、第三脑室宽度和钩间距与阿尔茨海默病有关(OR=3.222,1.507,1.271;95%CI:1.199～8.689,1.197～1.897和1.093～1.476);考虑不同部位白质病变评分时,脑血管病变、左侧额区白质病变评分、第三脑室宽度和钩间距与阿尔茨海默病有关(OR=2.876,1.744,1.548和1.268;95%CI:1.048～7.895,1.021～2.978,1.221～1.962和1.091～1.473);其中第三脑室宽度和钩间距OR值变化不明显。双侧侧裂宽度和侧脑室体部指数与阿尔茨海默病无关。剔除年龄和脑萎缩等影响因素后,多因素分析显示脑血管病变、左侧额区白质病变评分与阿尔茨海默病显著相关。结论阿尔茨海默病患者的脑血管病变和白质病变均可能促进阿尔茨海默病的发生和发展。控制脑血管疾病,减轻白质病变程度,将有助于阿尔茨海默病的防治。

Objective To explore the possible relationship between Alzheimer disease （AD） and cerebrovascular lesions, brain white matter lesions （WML） found in CT scanning. Methods A case-control study enrolled 60 AD patients in this hospital and age, sex matched 84 cognitive normal controls （NC）. The subjects＂ cerebral CT images of 3-5 years before establishing clinical diagnosis were analyzed by blind method. The location and number of cerebrovascular lesions were detected. WML of CT scans were evaluated with the Wahlund （2001） rating scale （ranged 0-3 scores）. The WML of frontal, parieto-occipital, temporal and subtentorial area in bilateral hemispheres were evaluated respectively, and total WML scores were the sum of the eight regions. The linear measures of medial temporal lobe, cerebral ventricles and fissures including interuncal distance, bilateral lateral fissure width, width of third ventricle, Huckman value, ventricular index and width of lateral ventricular body index were determined in order to understand the intensity of cerebral atrophy and cerebral ventricular enlargement. Results The cerebral CT images of AD patients showed obvious cerebrovascular lesions, WML, cerebral atrophy and cerebral ventricular enlargement. Cerebrovascular lesions were found by CT scanning in 15 cases （17.86%） of NC group and 33 cases （55.00%） of AD group, there was significant difference in univariate analysis between the two groups （P=0.000 1）. WML scores were higher in bilateral frontal and parieto-occipital regions and lower in bilateral temporal and subtentorial areas in both groups, it showed that total WML score, bilateral frontal WML and left parietooccipital WML, interuncal distance, bilateral lateral fissure width, width of third ventricle and lateral ventricular body index had significant difference （P〈 0.05） but there were no statistic significance in the difference of Huckman value and ventricular index be- tween two groups （P 〉 0.05）. Considering the total WML score in Logistic model the multivariate analysis showed that cerebrovascular lesions, width of third ventricle and interuncal distance were associated with AD, the OR and 95% confidence interval （95%CI） were 3.222, 1.507, 1.271 and 1.199-8.689, 1.197-1.897, 1.093-1.476 respectively. While the WML score of different regions were considered, it demonstrated that the cerebrovascular lesions, left frontal WML score, width of third ventricle and interuncal distance were associated with AD, the OR and 95%CI were 2.876, 1.744, 1.548, 1.268 and 1.048-7.895, 1.021-2.978, 1.221-1.962, 1.091-1.473 respectively. The bilateral lateral fissure width and lateral ventricular body index were not associated with AD. Multivariate analysis confirmed that after controlled the influence of ages and cerebral atrophy cerebrovascular lesions and left frontal WML score in CT scanning were significantly related to AD. Conclusion Cerebrovascular lesions and WML may promote the development of AD. To control cerebrovascular disease and alleviate the intensity of WML could help to the prevention and treatment of AD.