Duron Emmanuelle, Hanon Olivier
Hôpital Broca, Paris.
Psychol Neuropsychiatr Vieil. 2010 Sep;8(3):209-14. doi: 10.1684/pnv.2010.0222.
Atrial fibrillation (AF), which prevalence increases with age, is a growing public health problem and a well known risk factor for stroke. On the other hand, dementia is one of the most important neurological disorders in the elderly, and with aging of the population in developed countries, the number of demented patients will increase in absence of prevention. In the past decade, several vascular risk factors (hypertension, obesity and metabolic syndrome, hypercholesterolemia) have been found, with various degree of evidence, to be associated with vascular dementia but also, surprisingly, with Alzheimer's disease. This review is devoted to the links between atrial fibrillation, cognitive decline and dementia. Globally, transversal studies showed a significant association between atrial fibrillation, cognitive decline and dementia. However, these studies are particularly sensitive to various biases. In this context, recent longitudinal studies of higher level of evidence have been conducted to assess the link between AF and dementia. One study disclosed a high incidence of dementia among patients suffering from atrial fibrillation during a 4.6 years follow-up. Similarly another study showed that atrial fibrillation was significantly associated with conversion from mild cognitive impairment to dementia during a 3 years follow-up. Nevertheless two other longitudinal studies did not find any significant association between AF and dementia, but this discrepancy should be interpreted taking into account that the comparability of all these studies is moderate because they were using different methodologies (population, cognitive testing, and mean follow-up). Possible explanatory mechanisms for the association between AF and the risk of dementia are proposed, such as thrombo-embolic ischemic damage and cerebral hypo perfusion due to fluctuations in the cardiac output. Thus, there is some evidence that FA could be associated with cognitive decline and dementia but this link should be supported by more powerful long term longitudinal studies.
心房颤动（AF）的患病率随年龄增长而增加，它是一个日益严重的公共卫生问题，也是众所周知的中风危险因素。另一方面，痴呆是老年人中最重要的神经疾病之一，随着发达国家人口老龄化，如果不加以预防，痴呆患者的数量将会增加。在过去十年中，人们发现了几种血管危险因素（高血压、肥胖和代谢综合征、高胆固醇血症），有不同程度的证据表明它们与血管性痴呆有关，但令人惊讶的是，也与阿尔茨海默病有关。这篇综述致力于探讨心房颤动、认知衰退和痴呆之间的联系。总体而言，横向研究表明心房颤动、认知衰退和痴呆之间存在显著关联。然而，这些研究对各种偏差特别敏感。在这种背景下，最近进行了一些证据水平更高的纵向研究，以评估房颤与痴呆之间的联系。一项研究发现，在4.6年的随访期间，患有心房颤动的患者中痴呆的发病率很高。同样，另一项研究表明，在3年的随访期间，心房颤动与从轻度认知障碍转变为痴呆显著相关。然而，另外两项纵向研究没有发现房颤与痴呆之间有任何显著关联，但考虑到所有这些研究的可比性一般，因为它们使用了不同的方法（人群、认知测试和平均随访时间），所以应该对这种差异加以解释。有人提出了房颤与痴呆风险之间关联可能的解释机制，比如血栓栓塞性缺血损伤以及由于心输出量波动导致的脑灌注不足。因此，有一些证据表明房颤可能与认知衰退和痴呆有关，但这种联系应该得到更有力的长期纵向研究的支持。
