Canavan Michelle, O'Donnell Martin J
Health Research Board (HRB), Clinical Research Facility, National University of Ireland, Galway, Ireland.
Galway University Hospital, Galway, Ireland.
Front Neurol. 2022 Feb 4;13:821135. doi: 10.3389/fneur.2022.821135. eCollection 2022.
Cognitive impairment, and dementia, are major contributors to global burden of death and disability, with projected increases in prevalence in all regions of the world, but most marked increases in low and middle-income countries. Hypertension is a risk factor for both Vascular Cognitive Impairment and Alzheimer's disease, the two most common causes of dementia, collectively accounting for 85% of cases. Key end-organ pathological mechanisms, for which hypertension is proposed to be causative, include acute and covert cerebral ischemia and hemorrhage, accelerated brain atrophy, cerebral microvascular rarefaction and endothelial dysfunction, disruption of blood-brain barrier and neuroinflammation that affects amyloid pathologies. In addition to the direct-effect of hypertension on brain structure and microvasculature, hypertension is a risk factor for other diseases associated with an increased risk of dementia, most notably chronic kidney disease and heart failure. Population-level targets to reduce the incidence of dementia are a public health priority. Meta-analyses of blood pressure lowering trials report a significant reduction in the risk of dementia, but the relative (7-11%) and absolute risk reductions (0.4% over 4 years) are modest. However, given the high lifetime prevalence of both conditions, such relative risk reduction would translate into important population-level reductions in dementia globally with effective screening and control of hypertension. Optimal blood pressure target, especially in older adults with orthostatic hypotension, and antihypertensive agent(s) are uncertain. In this review article, we will detail the observational and interventional evidence linking hypertension with cognitive impairment, summarizing the mechanisms through which hypertension causes cognitive decline.
认知障碍和痴呆是全球死亡和残疾负担的主要促成因素，预计全球所有地区的患病率都会上升，其中低收入和中等收入国家的增幅最为显著。高血压是血管性认知障碍和阿尔茨海默病这两种最常见的痴呆病因的危险因素，这两种病因合计占病例的85%。高血压被认为是致病原因的关键终末器官病理机制包括急性和隐匿性脑缺血及出血、加速脑萎缩、脑微血管稀疏和内皮功能障碍、血脑屏障破坏以及影响淀粉样蛋白病变的神经炎症。除了高血压对脑结构和微血管的直接影响外，高血压还是与痴呆风险增加相关的其他疾病的危险因素，最显著的是慢性肾病和心力衰竭。降低痴呆发病率的人群层面目标是公共卫生的优先事项。降压试验的荟萃分析报告称痴呆风险显著降低，但相对风险降低（7-11%）和绝对风险降低（4年内为0.4%）幅度不大。然而，鉴于这两种疾病的终生患病率都很高，通过有效筛查和控制高血压，这种相对风险降低将在全球范围内转化为重要的人群层面痴呆发病率降低。最佳血压目标，尤其是在患有体位性低血压的老年人中，以及抗高血压药物尚不确定。在这篇综述文章中，我们将详细阐述将高血压与认知障碍联系起来的观察性和干预性证据，总结高血压导致认知下降的机制。
