Jellinger Kurt A
Institute of Clinical Neurobiology, Kenyongasse 18, A 1070 Vienna, Austria.
J Neurol Sci. 2008 Jul 15;270(1-2):1-12. doi: 10.1016/j.jns.2008.03.006. Epub 2008 May 2.
Vascular dementia/vascular cognitive impairment (VaD/VCI) is not a single entity, but a large group of conditions characterized by various clinical and morphological findings and variable pathophysiology. Clinical diagnostic criteria show moderate sensitivity (50-70%) and variable specificity (64-98%). Epidemiological studies are hampered by the lack of clear and validated diagnostic criteria, the complexity of brain pathologies, ethnic and geographic variations. In Western clinic-based series VaD/VCI is suggested in 8-15% of cognitively impaired aged subjects, with age-standardized incidence ratios 0.42-2.6 and clinical prevalence at age 70+ of 6-15/1000 person/year. Prevalence in autopsy series ranges from 0.03 to 58% (real mean 8-15% in Western series, 22-35% in Japan). Both prevalence and incidence increase with age. Neuropathology shows multifocal and/or diffuse lesions, ranging from lacunes and microinfarcts, white matter lesions, hippocampal sclerosis to multi-infarct encephalopathy, mixed cortico-subcortical and diffuse post-ischemic lesions. They result from systemic, cardiac, local large and small vessel disease. Pathogenesis is multifactorial and cognitive decline is commonly associated with small ischemic/vascular lesions, often involving subcortical and strategically important brain areas (thalamus, frontobasal, limbic system). Pathophysiology affects neuronal networks involved in cognition, behavior, execution and memory. Vascular lesions often coexist with Alzheimer disease (AD) and other lesions, multiple pathologies greatly increasing the odds of dementia; 25-80% of demented subjects show both AD and cerebrovascular lesions. While both factors by synergistic interaction contribute significantly to the risk of dementia, AD pathology is often less severe in the presence of vascular lesions. Due to the heterogeneity of cerebrovascular pathology and its causative factors, no validated neuropathologic criteria for VaD are currently available, and a large variability across laboratories still exists in morphologic examination procedures and techniques. Harmonization of neuropathologic procedures and evaluation criteria in future prospective clinico-pathologic studies are needed to validate diagnostic criteria for VaD and to clarify the impact of vascular lesions on cognition.
血管性痴呆/血管性认知障碍（VaD/VCI）并非单一疾病，而是一大类疾病，其特征为各种临床和形态学表现以及多样的病理生理学机制。临床诊断标准的敏感性中等（50 - 70%），特异性各异（64 - 98%）。由于缺乏清晰且经过验证的诊断标准、脑病理学的复杂性、种族和地域差异，流行病学研究受到阻碍。在西方以临床为基础的系列研究中，8 - 15%的认知受损老年受试者被诊断为VaD/VCI，年龄标准化发病率为0.42 - 2.6，70岁及以上人群的临床患病率为6 - 15/1000人/年。尸检系列研究中的患病率在0.03%至58%之间（西方系列研究的实际平均患病率为8 - 15%，日本为22 - 35%）。患病率和发病率均随年龄增长而增加。神经病理学表现为多灶性和/或弥漫性病变，范围从腔隙性梗死和微梗死、白质病变、海马硬化到多梗死性脑病、混合性皮质 - 皮质下和弥漫性缺血后病变。这些病变由全身性、心脏、局部大血管和小血管疾病引起。发病机制是多因素的，认知功能下降通常与小的缺血性/血管性病变相关，这些病变常累及皮质下和具有重要战略意义的脑区（丘脑、额基底、边缘系统）。病理生理学影响参与认知、行为、执行和记忆的神经网络。血管病变常与阿尔茨海默病（AD）及其他病变共存，多种病理改变极大增加了患痴呆症的几率；25 - 80%的痴呆患者同时存在AD和脑血管病变。虽然这两个因素通过协同相互作用对痴呆风险有显著影响，但在存在血管病变的情况下，AD病理改变通常不太严重。由于脑血管病理学及其致病因素的异质性，目前尚无经过验证的VaD神经病理学标准，不同实验室在形态学检查程序和技术方面仍存在很大差异。未来前瞻性临床病理研究需要统一神经病理学程序和评估标准，以验证VaD诊断标准并阐明血管病变对认知的影响。
