Institute of Clinical Neurobiology, Vienna, Austria.
J Alzheimers Dis. 2010;21(4):1283-93. doi: 10.3233/jad-2010-100603.
The prevalence of both Alzheimer's disease (AD) and vascular dementia (VaD) increase with advancing age, but epidemiologic data above age 85 are imprecise and inconsistent. A retrospective hospital-based study of the prevalence and pathology of VaD was performed in 1700 consecutive autopsy cases of demented elderly in Vienna, Austria (mean age 84.3 ± 5.4 SD; 90% over age 70). It assessed clinical and general autopsy data and neuropathology including immunohistochemistry. Neuropathologic diagnosis followed current consensus criteria. Four age groups (7th to 10th decade) were evaluated. "Pure" VaD (due to cerebrovascular disease without other pathologies; neuritic Braak stages 1.2-1.6) was observed in 12.3% of the total cohort, decreasing between age 60 and 90+ from 15.0 to 8.7%. Morphologic subtypes (subcortical arteriosclerotic encephalopathy, multi-infarct encephalopathy, and strategic infarct dementia) showed no age-related differences. By contrast, AD (without concomitant pathologies; 45.6% of total), mixed dementia (AD + cerebrovascular encephalopathy; 5.5%), and AD with minor cerebrovascular lesions (22.3%) increased with age. The relative prevalence of AD + Lewy pathology (9.3%) remained fairly stable, whereas other dementias (5.0%) decreased significantly over age 90. 85% of the patients with "pure" VaD had histories of diabetes, 75% of stroke(s), 95% morphologic signs of hypertension, 65% myocardial infarction (recent and old ones), 97% cerebral hypertonic-arteriosclerotic microangiopathy (associated with cerebral amyloid angiopathy in 23%) and 90% severe atherosclerosis of large cerebral arteries. Similar autopsy findings were seen in mixed dementia (MIX) and in AD + minor cerebrovascular lesions. Major vascular lesions differed between VaD and MIX, VaD showing more than 60% subcortical infarcts, MIX only 43% such lesions. This retrograde hospital-based study using strict morphologic diagnostic criteria confirmed the existence of "pure" VaD in old age, with a tendency to decline after age 90, while AD and AD + cerebrovascular pathologies showed considerable age-related increase, and "pure" AD slightly decreasing after age 90.
阿尔茨海默病（AD）和血管性痴呆（VaD）的患病率随着年龄的增长而增加，但 85 岁以上的流行病学数据并不精确且不一致。对奥地利维也纳 1700 例连续进行尸检的老年痴呆患者的 VaD 患病率和病理学进行了回顾性医院研究（平均年龄 84.3±5.4SD；90%以上超过 70 岁）。评估了临床和一般尸检数据以及包括免疫组织化学在内的神经病理学。神经病理学诊断符合当前的共识标准。评估了四个年龄组（第 7 至 10 个十年）。“纯”VaD（由于脑血管疾病而无其他病理学；神经原纤维缠结 Braak 分期 1.2-1.6）占总队列的 12.3%，从 60 岁到 90+岁，从 15.0%降至 8.7%。形态亚型（皮质下动脉硬化性脑病、多发性梗死性脑病和战略梗死性痴呆）无年龄相关性差异。相比之下，AD（无伴随病理学；占总病例的 45.6%）、混合性痴呆（AD+脑血管性脑病；5.5%）和 AD 伴轻微脑血管病变（22.3%）随年龄增长而增加。AD+路易体病理学（9.3%）的相对患病率相对稳定，而其他痴呆症（5.0%）在 90 岁以上显著下降。85%的“纯”VaD 患者有糖尿病病史，75%有中风史，95%有形态学高血压征象，65%有心肌梗死（近期和陈旧性），97%有脑高张力-动脉粥样硬化性微血管病（与脑淀粉样血管病相关，占 23%），90%有大脑大血管严重动脉粥样硬化。混合性痴呆（MIX）和 AD+轻微脑血管病变中也有类似的尸检发现。VaD 与 MIX 之间主要血管病变不同，VaD 有超过 60%的皮质下梗死，而 MIX 仅有 43%的此类病变。这项使用严格形态学诊断标准的回顾性医院研究证实了老年“纯”VaD 的存在，90 岁以后有下降趋势，而 AD 和 AD+脑血管病理学有相当大的年龄相关性增加，90 岁以后“纯”AD 略有下降。
