Abstract:
While the link between aging and mortality from dementia is widely appreciated, the mechanism is not clear. The objective of this study was to determine whether there is a direct relationship between Alzheimer dementia (AD) and the QT interval, because the latter has been related to cardiac mortality. A systematic review and meta-analysis were conducted after a Medline and EMBASE search using terms \"Alzheimer disease or Dementia AND QT interval, QT dispersion or cardiac repolarization.\" Four studies with control groups were identified. There were significant differences in QT interval between individuals with AD vs individuals without dementia (controls) (odds ratio (OR)1.665 [random effects model] and 1.879 [fixed effect model]) (p < 0.001). There were significant differences in QT interval between individuals with AD vs individuals with mild cognitive impairment (MCI) (OR 1.760 [random effects] and 1.810 [fixed effect]) (p < 0.001). A significant (p <0.001) correlation exists between the QTc and the Mini-Mental State Exam (MMSE), a test of cognitive function. Two studies examined QT variability (the difference between the longest and shortest QT interval on a 12 lead ECG); the OR for QT variability AD vs MCI was 3.858 [random effects model] and 3.712 [fixed effects model] (p < 0.001). When compared to the control group, the OR for QT dispersion in AD was 6.358 [random effects model] or 5.143 ( P< 0.001) [fixed effects model]. A qualitative analysis of the data raised questions about paucity of data defining the nature of the control groups, the pathophysiologic mechanism, and the uniform use of a poor QT heart rate correction factor. The longer QT in AD, greater QT variability in AD, and the direct relationship between QT interval and AD severity supports a brain-heart connection in AD that might be fundamental to aging-induced AD and mortality. Issues with defining the control group, limited number of studies, conflicting data in population studies, and the lack of a strong electrophysiological basis underscore the need for additional research in this field.
摘要:
虽然衰老与痴呆症死亡率之间的联系得到了广泛的认可,机制尚不清楚。这项研究的目的是确定阿尔茨海默痴呆(AD)与QT间期之间是否存在直接关系,因为后者与心脏死亡率有关。在Medline和EMBASE搜索后,使用术语“阿尔茨海默病或痴呆和QT间期”进行系统评价和荟萃分析。QT离散度或心脏复极。“确定了四项与对照组的研究。AD患者与无痴呆患者(对照)之间的QT间期存在显着差异(比值比(OR)1.665[随机效应模型]和1.879[固定效应模型])(p<0.001)。AD患者与轻度认知障碍(MCI)患者之间的QT间期存在显着差异(OR1.760[随机效应]和1.810[固定效应])(p<0.001)。QTc和迷你精神状态考试(MMSE)之间存在显著(p<0.001)相关性,认知功能的测试.两项研究检查了QT变异性(12导联心电图上最长和最短QT间期之间的差异);QT变异性AD与MCI的OR分别为3.858[随机效应模型]和3.712[固定效应模型](p<0.001)。与对照组相比,AD患者QT离散度的OR为6.358[随机效应模型]或5.143[固定效应模型](P<0.001).对数据的定性分析提出了有关定义控制组性质的数据匮乏的问题,病理生理机制,和均匀使用不良的QT心率校正因子。AD中QT越长,AD的QT变异性更大,QT间期和AD严重程度之间的直接关系支持AD的脑-心脏连接,这可能是衰老引起的AD和死亡率的基础。定义控制组的问题,研究数量有限,人口研究中相互矛盾的数据,缺乏强大的电生理基础强调了在这一领域进行更多研究的必要性。