(4)模块1---认知症可以预防吗?Can Dementia be Prevented?-公开课-关爱惟士
(4)模块1---认知症可以预防吗?Can Dementia be Prevented?

课程视频http://player.youku.com/embed/XMzYwNDQ3Nzk5Mg



Prof. Carol Brayne

Carol Brayne 教授


We all hope to have prevention. Medical practitioners treat people, and we deal with diseases and disorders when they're present, but most people understand that it's better to think about prevention.

我们都希望能预防所有疾病。生病了我们找医生,需要他们来处理我们的各种疾病和状况,但很多人心知肚明,最好的方法是预防。


Well, what do we mean by prevention? We mean trying to stop something, a disease, happening at all, and in ageing we know that dementia becomes very much more common and there's a sense that it might be inevitable, but there's also evidence that it might not be as inevitable as we had thought. So although the increase in dementia is very related to age in our populations, there is some evidence that we can reduce our risks of developing dementia, so in some terms that could be viewed as prevention.

那么,预防的意思是什么呢?它指的是尝试去阻止疾病的发生发展,认知症随着社会老龄化已经变得越来越常见,普遍认为它是不可逆的,不过同时也有证据显示它在某些方面并不像我们想象中那样不可逆转。尽管认知症和衰老存在相关性,但是有证据显示,认知症的风险是可以被降低的,所以从这个角度说,认知症可以被预防。


So we understand that dementia, particularly in the oldest old where it's most common, is a mixture of classical Alzheimer's type, which most people have heard of, but also of vascular changes. And that's related to earlier life, what we call non-communicable diseases, which includes things like heart disease and diabetes. Now we've got very good understanding of how to prevent those disorders in the population and those relate to both individually-based prevention but also predominantly to societally-based activities or interventions, such as the smoking bans and trying to reduce excessive alcohol and so on. So these are all factors which can improve health earlier in life and reduce the risk of the risk factors for dementia, and so we have pretty good evidence on those.

我们知道认知症,最常见于一些高龄老年群体,它是以最为熟知的阿尔茨海默病为典型代表加上血管病变的一类综合征。认知症在早期与一些像心脏病和糖尿病这样的非传染病相关。现在我们早已知道如何预防这些疾病,包括个体水平为基础的预防以及像禁烟令、建议减少过量饮酒等等这样基于社会水平的活动或者干预手段。这些是可以在早期提高健康水平减少认知症患病风险的因素,当然我们有很多有力的证据来支持以上观点。


I've been working in the field of dementia research for 30 years and for decades I thought that we could not reduce our risk of dementia because it was so closely associated with age. But, when we did the research that suggested that - well, which showed that dementia prevalence, that is the proportion of people who had dementia at any given age, has gone down, I realised that we do have the potential to reduce our risk. It does not mean that we will eradicate dementia because what it means is that we still have a lot of dementia in the oldest old because age is such a powerful risk factor. Because we're living longer, we have more people in the oldest age groups. So we can't prevent all dementia but we might reduce our risk at particular ages.

我已经在认知症研究领域工作了30年,在几十年里,我一直在思考我们之所以不能降低认知症风险,是因为它跟年龄老化有着极大的关系。但是,当我们在研究那些课题时-它显现出认知症的发展趋势,就是认知症在任何年龄阶段的发病几率,并显示下降趋势,因此我意识到我们有可能降低认知症风险。这不是说可以根除认知症,毕竟相当多的认知症是发生在老年阶段,年龄衰老对认知症是非常强大的风险因素。因为我们的寿命增长,我们有老年群体也随之增大。因此我们不能预防所有的认知症,但是我们或许可以在特殊的年龄阶段降低认知症的发病风险。


Researchers for decades have been looking at the risk factors for dementia in a variety of different ways. A lot of these have been what we call cohort studies, which is following people over time who start out without dementia and then, having examined what their risk factors, or what might be risk factors, are at baseline, we then follow them up over time and identify who gets dementia or who meets diagnostic criteria for dementia over time and who doesn't.

做了多年研究的学者们,应用大量不同的方法去寻找认知症风险因素。大多数应用的是我们称之为“队列研究”的方法,即全称追踪初始并不是认知症的患者,了解他们已有的或者可能的风险因素,这是基线阶段,然后我们从始至终随访这些病人,确定谁患有认知症或者谁满足诊断标准或者谁不符合标准。


Those studies have looked at risk factors close to the expression of dementia and have looked at midlife risk factors as well, and also life course risk factors. Putting all of that together requires systematic reviewing and there have been several exercises in systematic reviewing of the risk factors for dementia in the last decade. One of those identified seven risk factors and it was a very rigorous look at the world literature and it came up with seven, and they included things from across the life course, such as low educational attainment, midlife obesity and hypertension, and then depression and diabetes, and so-called lifestyle behaviours such as smoking.

这些研究所涉及的风险因素都是和认知症的症状相关的,也涉及中年期或者生命全周期风险因素。把它们整理在一起是需要做系统回顾审查,最近十年已经对认知症患病风险因素做了很多系统回顾审查。其中七个已确定风险因素浮出水面,我们仔细地查询了全球范围内的文献,文献也显示为七个风险因素,它所包括的因素贯穿整个生命周期,比如像低受教水平、中年肥胖、高血压、抑郁症以及糖尿病,也包括了我们常提到的不良生活方式-比如吸烟。


That exercise has been done in the US as well, as well as the Lancet Commission, and the exact risk factors have been sort of changed a little bit, so there's the addition recently of midlife hearing loss in particular.

美国以及柳叶刀委员会也做了相关类似的实验,他们对风险因素做了轻微的改动,他们特别增加了一个风险因素:中年期听力丧失。


If you put all of those risk factors together and try to understand how they operate in different populations, looking at the exposure of the population to the particular risk factors, you can calculate what proportion of people might - what proportion of dementia might be attributed to that risk factor or those risk factors. Now the risk factors cluster. Once you take that clustering into account, all of the different exercises come up with roughly a third of dementia that might be prevented if we assume a causal relationship between the risk factors and dementia. So the ultimate message from those analyses is that, if we pay attention to those risk factors across the life course, we might reduce dementia by about a third over time.

如果你把这些所有风险因素进行归纳,尝试去搞清楚它们是如何作用于不同的群体里,找到具备这些风险因素的群体,你可以计算出比例 -一个或多个风险因素在多大比例上导致认知症发生。现在我们把这些风险因素进行归纳,现在我们把所有风险因素考虑进去,假设风险因素同认知症之间存在因果关系,所有不同的实验都显示出大约三分之一的认知症可以被预防。所以最终分析得出的信息就是,如果在全生命周期中能够注意这些风险因素,那么我们或许可以逐渐降低三分之一的认知症。


Speaking from a public health perspective, the idea of removal of one risk factor doesn't work terribly well in populations. What we need to do is look at the clustering of the risk factors and see which sectors of the population are at risk with different profiles of those risks, and what is our knowledge about how to address those risks in those populations and in the population at large. So, for example, smoking has reduced enormously and perhaps that is a single risk factor example where we have had a huge effect, but that has been done through legislation and whole-society action. But something as complicated as midlife obesity, midlife hypertension and consequently stroke and so on are much more complicated. So unless we create environments in which we can be healthy and optimise our ageing and our brain health, we're unlikely to be able to affect those particular risks in a big way for the populations.

从公共健康的角度来说,仅仅根除一个风险因素的想法在大众范围很难起到很大成效。我们需要做的是观察哪些群体处于哪种风险因素中及他们不同的风险特征,还有我们的知识体系如何大范围解决这些人的风险因素。比如吸烟行为已经减少了很多,它作为一个独立的风险因素产生了很大的影响,国家通过立法及整个社会协作通过一些行动已经使其得到控制。但相比中年肥胖,中年高血压及由此造成的中风等等这些因素,情况却复杂得多。如果我们不能创造一个健康积极的环境,同时延缓衰老和强健大脑,否则我们不太可能大规模地在大众范围内改变这些风险因素。


Not only are risks very complicated in the way that they interact with each other and the behaviour - so we have behaviours, we have disorders and diseases which all interact and they're all our individual profile of risk, but also, when we look at people who have dementia, and it's most common in people aged 80 and over, so if we look in the brains of people who have died with dementia as well as the people who haven't died with dementia, we see that everybody, by the age of 85, 90, has got a mixture of pathologies and changes in their brain, which include atrophy and vascular changes and changes which could be associated with Parkinson's disease as well as the Alzheimer's disease changes, and it's rare to find somebody with a brain at the age of 100 who doesn't have at least some of these pathologies, and the relationship of those with the expression of dementia, with whether the person had dementia, becomes more complicated in the oldest age group.

这些风险因素不但复杂,而且它们之间以及它们和行为之间互相作用, -这就是为什么我们会产生问题行为,功能紊乱以及疾病,这些都是风险因素在个体水平相互作用的体现,而且当我们观察那些死去的或者健在的80岁或以上的认知症患者的大脑,85至90岁的老人出现混合性的病理病变,及可能与帕金森病以及阿尔茨海默氏病等疾病相关的大脑萎缩和血管变化,我们很少发现100岁左右的大脑中没有这些病变的,至少有一部分。高龄老人中认知症的表现和此人是否患有认知症的相互关系是更复杂的。


There is very good evidence now from a variety of different studies, from animal studies through to human studies through to population studies, that there are factors that protect us from dementia, even when we have, say, the neuropathologies that are thought to be classically associated with dementia. So there is good evidence that we can protect the population and protect individuals to some extent, or reduce their likelihood of experiencing dementia during their lives, and these factors probably need to be addressed at different times in the life course.

从动物实验到人体实验到大规模试验我们得到了一些乐观的证据,就是即使有一些和患有认知症相关的典型神经病理改变,但是也有一些保护性因素使我们可以远离认知症。我们同样有证据表明在一定程度上我们可以保护我们大众群体或者降低他们一生中患认知症的可能性,无论从群体上还是从个体上,这些因素在整个生命周期的不同阶段可能需要被强调。


So we have evidence from early life, from midlife and from later life of the kinds of things that appear to protect us from dementia. We can improve aging, we can improve brain aging and we can probably reduce the amount of dementia at any given age and we can reduce that frailty right at the end of life that is almost inevitable for all of us, but maybe reduce the time that we have to experience that through population health activities and a balance of individual and public health, if you like, actions.

所以无论是早期,还是中年到晚年,我们都有证据显示可以通过一些手段使我们远离认知症。我们通过延缓衰老,强化大脑,就有可能降低不同年龄层认知症患者的数量,使每个人在不可避免的生命尽头时减少无助及痛苦。所以我们需要整个社会开始付诸行动,通过一些公共健康活动来减少经受疾病折磨的时间,如果你愿意,行动起来!


翻译:关爱惟士-未经允许不得转载,违者必追究法律责任

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