Department of Gerontology and Geriatrics, Leiden University Medical Center, The Netherlands.
Ageing Res Rev. 2012 Apr;11(2):271-7. doi: 10.1016/j.arr.2011.12.009. Epub 2011 Dec 27.
Alteration in cerebrovascular hemodynamics has reported in both ageing and dementia. However, it is still unclear whether this alteration follows similar pattern in ageing and in different dementia pathologies. The aim of this meta-analysis was to investigate changes in cerebral blood flow velocity and pulsatility index in two most common forms of dementia; Alzheimer's disease and vascular dementia, using transcranial Doppler studies.
A literature search was conducted in Pubmed, EMBASE and Web of Science. After initial screening of 304 articles and removing duplicates, a total of 53 articles, published between 1980 and 2010, were reviewed. Finally 12 articles were included in the meta-analysis. For each study, effect sizes (ES) indicating the standardized mean differences of the hemodynamic measures between two groups were calculated. Using random effect models, pooled estimates of ES were measured.
Patients with Alzheimer's disease (ES=-1.09, 95% CI -1.77 to -0.44, p=0.004) and vascular dementia (ES=-1.62, 95% CI -2.26 to -0.98, p<0.001) had significantly lower cerebral blood flow velocity compared with healthy aged-matched controls. In addition, pulsatility index was significantly higher in both Alzheimer's disease (ES=0.5, 95% CI 0.28-0.72, p<0.001) and vascular dementia patients (ES=2.34, 95% CI 1.39-3.29, p<0.001). Patients with Alzheimer's disease had lower pulsatility index (ES=-1.22, 95% CI -1.98 to -0.46, p=0.002) compared to subjects with vascular type of dementia.
Patients with Alzheimer's disease and vascular dementia have a pronounced disturbance in their cerebrovascular hemodynamics. The severity of disturbances in cerebral hemodynamics is significantly lower in Alzheimer's disease compared to vascular dementia.
脑血管血流动力学的改变在衰老和痴呆中均有报道。然而，目前尚不清楚这种改变在衰老和不同的痴呆病理中是否遵循相似的模式。本研究旨在通过经颅多普勒研究，探讨两种最常见的痴呆症（阿尔茨海默病和血管性痴呆）患者的脑血流速度和搏动指数的变化。
在 Pubmed、EMBASE 和 Web of Science 上进行文献检索。在对 304 篇文章进行初步筛选并去除重复项后，共回顾了 53 篇发表于 1980 年至 2010 年之间的文章。最终有 12 篇文章纳入荟萃分析。对于每一项研究，计算了表示两组血流动力学指标标准化均值差异的效应量（ES）。采用随机效应模型，测量了合并效应量的估计值。
与健康老年对照组相比，阿尔茨海默病（ES=-1.09，95%CI-1.77 至-0.44，p=0.004）和血管性痴呆（ES=-1.62，95%CI-2.26 至-0.98，p<0.001）患者的脑血流速度明显降低。此外，阿尔茨海默病（ES=0.5，95%CI0.28-0.72，p<0.001）和血管性痴呆（ES=2.34，95%CI1.39-3.29，p<0.001）患者的搏动指数明显升高。与血管性痴呆患者相比，阿尔茨海默病患者的搏动指数较低（ES=-1.22，95%CI-1.98 至-0.46，p=0.002）。
阿尔茨海默病和血管性痴呆患者的脑血管血流动力学存在明显紊乱。与血管性痴呆相比，阿尔茨海默病患者的脑血流动力学紊乱程度明显较轻。
