血管性痴呆研究述评

The Review of Research on Vascular Dementia

血管性痴呆在欧洲和美国是仅次于阿茨海默氏病的第二位最常见的痴呆，然而，在亚洲及许多发展中国家血管性痴呆的发病率超过了阿茨海默氏病。流行病学研究表明，血管性痴呆的发病率随年龄而直线上升，且国家之间有很大差异。在调整年龄和性别之后，65岁以上老年人发病率在1.2％～4.2％，其患病率比发病率更具有同种性，估计70岁以上老年人每年患病人数在6～12例／1000人。平均病程5年左右，而且存活者低于普通人群和阿茨海默氏病人。血管性痴呆的主要危险因素是高血压、糖尿病、心脏病和中风。虽然有些危险因素是可以缓解的，但至今尚无预防效果的研究报道。血管性痴呆可由多发性梗塞、白质缺血或一个战略性部位的梗塞引起。有症状的中风可使患痴呆的危险性增加9倍。脑梗塞或损伤的部位、大小、数量及频次与血管性痴呆发病率有关。检查发现的病灶性神经功能损害的证据和CT、MRI发现的脑血管病对确定诊断与鉴别诊断有帮助；认知神经心理学评价仍是确定痴呆和鉴别诊断不可缺少的。脑资液中胆碱和乙酸胆碱的浓度有助于血管性痴呆与阿茨海默氏型痴呆的鉴别。阿朴脂蛋白E4在血管性痴呆和阿茨海默氏型痴呆中都显著增高，但与无痴呆的脑血管病比较无显著性差异。皮肤纤维细胞阿朴脂蛋白Em核糖核酸水平在血管性?

Vascular dementia (VD) is the Second commonest dementia after Alzheimer's disease (AD) inEurope and USA. However, in Asia and many developing countries the Prevalence of VD exceeds that of AD. Epidemiological studies show that the prevalence of VD increases linearly with age and varies greatly from Country tocountry, ranging form 1.2% to 4.2% of people over 65 years old, even after adjustment for age and sex. The incidence of VD is more homogeneous than prevalence and is estimated at 6~ 12 cases per 1, 000 persons over 70 yearsper year. The mean duration of the disease is around 5 years and survival is less than for the general population andfor AD. The major risk factors for VD appear to be hypertension, diabetes, heart disease and stroke. Although someof these risk factors are modifiable, there is no study on the efficacy of prevention of VD. VD may be caed bymultiple infarcts, white matter ischemia, or a infarct in a strategical place. The site, size, number, and frequency ofcerebral infarct or lesion are relative to prevalence rate of VD. Evidence of focal neurological deficit on examinationand cerebrovascular disease on computed tomography or magnetic resonance imaging is helpful to determine diagnosisand differentiation of VD. Cognitive neuropsychological assessment is helpful to diagnose and differentiate AD andother types of dementia. The simultaneous determination of Ach and Ch concentrations in cerebrospinal fluid may beuseful for differentiating vascular dementia of the Binswanger type or multiple small infarct type from Alzheimer typedementia. The frequency of the ApoE epsilon 4 allele is significantly higher in the patients with AD and VD, but issighficantly different in the cerebrovascular disease without dementia; the skin fibroblast ApoE mRNA level in theAD and VD Patients is significantly lower than in control group, which indicates that ApoE4 allele and ApoE mRNAlevel might be of value for diagnosis of AD. All patients with possible VD need careful assessment to detect any underlying causes and risk factors that may be remediable. No breakout Progress of treatment is available until now.Early hopes that calcium channel blockers such as nimodipine would be of value have not been sustained. Several further strategies──for example, to protect neurones from excitoxins or reinforce other neuroprotective mechanisms──are under further evaluation, but it is too early to be certain of their potential in the clinical context.