PBS高端访谈:痴呆人数的下降带来了积极的生活情绪

 　　GWEN IFILL: New research suggests there may be some good news in the struggle against dementia.

　　Two recently released studies show severe memory loss declining among healthier and better educated populations. In England and in Wales, dementia rates over the last two decades have dropped by 25 percent among those 65 and older.

　　And in Denmark, the percentage of elderly whose cognitive¹ abilities were severely² impaired³ also dropped between 1998 and 2010.

　　In the United States, about five million people have Alzheimer's disease, but that number is expected to rise sharply as baby boomers age.

　　For more, we're joined by Dr. Murali Doraiswamy, director of the Neurocognitive Disorders⁴ Program at the Duke University School of Medicine.

　　Thank you for joining us.

　　DR. MURALI DORAISWAMY, Duke University School of Medicine: Thank you very much. Great pleasure to be on.

　　GWEN IFILL: What are the most hopeful signs you see in these new studies?

　　MURALI DORAISWAMY: Well, this is terrific news.

　　The so-called silver tsunami⁵ that we have all been scared of has just downgraded from grade five to grade four.

　　So, the key thing to keep in mind is we're not out of the woods, but what these two studies are telling us is that successive generations or even slightly younger cohorts separated by as little as 10 years apart may not have the same risk.

　　So in other words, our children or our grandchildren may not have the same risk for Alzheimer's that we do. The second thing I think that these studies are pointing out is if the risk for Alzheimer's is going down with successive generations, then that is good news because it indicates that it is likely to be due to environmental or lifestyle effects.

　　In other words, many of the public health interventions⁶ that have been put into place since the 1970s, such as encouraging Americans and people all over the world to exercise more, cutting down on smoking, the disappearance⁷ of the Marlboro Man, if you will, eating healthier, and indeed better education, I think all of these things might be having an effect.

　　GWEN IFILL: But do you see any red flags in this research? We're talking about England and Wales. They're not necessarily the same type of population as we see here in the U.S., for instance.

　　MURALI DORAISWAMY: That's not the main red flag.

　　There are studies that have been done in Sweden, in the U.S., in many countries that show the same essential decreasing incidence rates, if you will, for Alzheimer's in successive generations.

　　That said, these are also called observational studies, so these are not clinical trials, where people are sort of randomly⁸ assigned to different treatment arms. So, we cannot be sure, but I think the signs from all these different studies in multiple countries all are pointing in the same direction.

　　GWEN IFILL: But at an Alzheimer's meeting conference today, they were talking about memory loss being more of a warning sign than we have been necessarily led to believe. We have been told, well, losing your keys is not necessarily a problem, but now people are saying maybe it is. Help us with that.

　　MURALI DORAISWAMY: Well, memory problems have always been a warning sign of Alzheimer's.

　　I think what scientists are discovering now is that Alzheimer's can often start in a very, very mild form called a subjective⁹ cognitive impairment. These are not the so-called benign¹⁰ senior moments where you forget your key or you occasionally have a tip-of-the-tongue problem.

　　I think what we're talking about are much more serious memory problems, where people are not even remembering what they forgot. They're having trouble planning. They are forgetting the names of loved ones and those names never come back.

　　If you forget something and it comes back to you a couple of hours later, it's probably benign. But, that said, this research is still in early days, but I think the key point to remember is that there could be many, many causes of memory loss as you get older. If your memory problems start affecting your daily functioning, then that's when you need to take it more seriously.

　　And it doesn't always have to be Alzheimer's, because a number of conditions can mimic¹¹ Alzheimer's, and many of them are reversible, such as depression or vitamin deficiencies or thyroid problems.

　　GWEN IFILL: And there are other measures of brain health that you use to make these determinations, just besides diet or other health measures, right?

　　MURALI DORAISWAMY: Absolutely.

　　When we see someone coming in with mild memory complaints, we run the full battery of laboratory tests. We also do formal neuropsychological testing. And sometimes we have to get brain scans to make sure that it's not a small stroke or some other lesion in the brain that's causing these.

　　But for the vast majority of people with mild forgetfulness, I don't think they have anything to worry about.

　　GWEN IFILL: How do these stories square with -- we -- it feels like every six weeks, six months, we do another story on this program about another study.

　　How does this square about the one we heard that in the next 30 years, Americans with Alzheimer's will double? Are we talking about people who are alive now, as opposed to our children? Is it a question of scope?

　　MURALI DORAISWAMY: Well, so, first of all, you have to realize that many of these forward projections¹² are merely estimates, and some of the previous projections fail to take into account the fact that with better health improvements, with reduction of cardiovascular disease, with reduction of smoking, with more exercise, the rates of Alzheimer's may actually go down in the future.

　　So, many of these projections are assuming that the rates are going to hold steady or are going to go up simply because of the rise in the older population.

　　So, the bottom line is public officials now probably have to revise some of these estimates a little bit lower, so, it's good news, but we're not entirely¹⁴ out of the woods.

　　GWEN IFILL: Now, dementia is a much broader umbrella than Alzheimer's specifically. So, if there's good news on dementia, does that always mean -- also mean there's good news on Alzheimer's and more specific cases?

　　MURALI DORAISWAMY: Most of the time, but not always.

　　It could very well be that much of the reductions that we're seeing are reductions in a type of dementia calls vascular¹³ dementia, which is accounted largely by cardiovascular disease, by strokes, by high blood pressure, by high cholesterol¹⁵.

　　I suspect that that is the area where we have made the biggest gains, because we now have better ways to treat cardiovascular disease. I suspect that Alzheimer's has also gone down a little bit because we're getting better at education. And Alzheimer's is also linked to heart disease, even though not as strongly as vascular dementia.

　　GWEN IFILL: But we don't know for sure that the rate yet -- we don't have any reliable studies that show that the rate of Alzheimer's is declining, like the rate of dementia, as we see in these studies?

　　MURALI DORAISWAMY: So, I think what we have to differentiate¹⁶ is the risk vs. the total numbers.

　　The total numbers of Alzheimer's disease are going to climb upwards¹⁷ quite dramatically because older age and the rising number of people who live into their 70s, and 80s and 90s is a huge risk factor for Alzheimer's.

　　But within each generation, what we're seeing is a given person's risk for developing Alzheimer's might actually reduce and go down.

　　GWEN IFILL: Dr. Murali Doraiswamy of Duke University, thank you very much for helping¹⁸ us out.

　　MURALI DORAISWAMY: Thank you very much.

1 cognitive   

adj.认知的，认识的，有感知的

参考例句：

• As children grow older,their cognitive processes become sharper.孩子们越长越大，他们的认知过程变得更为敏锐。
• The cognitive psychologist is like the tinker who wants to know how a clock works.认知心理学者倒很像一个需要通晓钟表如何运转的钟表修理匠。

2 severely   

adv.严格地；严厉地；非常恶劣地

参考例句：

• He was severely criticized and removed from his post.他受到了严厉的批评并且被撤了职。
• He is severely put down for his careless work.他因工作上的粗心大意而受到了严厉的批评。

3 impaired   

adj.受损的；出毛病的；有（身体或智力）缺陷的v.损害，削弱( impair的过去式和过去分词 )

参考例句：

• Much reading has impaired his vision. 大量读书损害了他的视力。 来自《现代汉英综合大词典》
• His hearing is somewhat impaired. 他的听觉已受到一定程度的损害。 来自《现代汉英综合大词典》

4 disorders   

n.混乱( disorder的名词复数 )；凌乱；骚乱；（身心、机能）失调

参考例句：

• Reports of anorexia and other eating disorders are on the increase. 据报告，厌食症和其他饮食方面的功能紊乱发生率正在不断增长。 来自《简明英汉词典》
• The announcement led to violent civil disorders. 这项宣布引起剧烈的骚乱。 来自《简明英汉词典》

5 tsunami   

n.海啸

参考例句：

• Powerful quake sparks tsunami warning in Japan.大地震触发了日本的海啸预警。
• Coastlines all around the Indian Ocean inundated by a huge tsunami.大海啸把印度洋沿岸地区都淹没了。

6 interventions   

n.介入，干涉，干预( intervention的名词复数 )

参考例句：

• Economic analysis of government interventions deserves detailed discussion. 政府对经济的干预应该给予充分的论述。 来自辞典例句
• The judge's frequent interventions made a mockery of justice. 法官的屡屡干预是对正义的践踏。 来自互联网

7 disappearance   

n.消失，消散，失踪

参考例句：

• He was hard put to it to explain her disappearance.他难以说明她为什么不见了。
• Her disappearance gave rise to the wildest rumours.她失踪一事引起了各种流言蜚语。

8 randomly   

adv.随便地，未加计划地

参考例句：

• Within the hot gas chamber, molecules are moving randomly in all directions. 在灼热的气体燃烧室内，分子在各个方向上作无规运动。 来自辞典例句
• Transformed cells are loosely attached, rounded and randomly oriented. 转化细胞则不大贴壁、圆缩并呈杂乱分布。 来自辞典例句

9 subjective   

a.主观(上)的，个人的

参考例句：

• The way they interpreted their past was highly subjective. 他们解释其过去的方式太主观。
• A literary critic should not be too subjective in his approach. 文学评论家的看法不应太主观。

10 benign   

adj.善良的，慈祥的；良性的，无危险的

参考例句：

• The benign weather brought North America a bumper crop.温和的气候给北美带来大丰收。
• Martha is a benign old lady.玛莎是个仁慈的老妇人。

11 mimic   

v.模仿，戏弄；n.模仿他人言行的人

参考例句：

• A parrot can mimic a person's voice.鹦鹉能学人的声音。
• He used to mimic speech peculiarities of another.他过去总是模仿别人讲话的特点。

12 projections   

预测( projection的名词复数 )； 投影； 投掷； 突起物

参考例句：

• Their sales projections are a total thumbsuck. 他们的销售量预测纯属估计。
• The council has revised its projections of funding requirements upwards. 地方议会调高了对资金需求的预测。

13 vascular   

adj.血管的，脉管的

参考例句：

• The mechanism of this anomalous vascular response is unknown.此种不规则的血管反应的机制尚不清楚。
• The vascular changes interfere with diffusion of nutrients from plasma into adjacent perivascular tissue and cells.这些血管变化干扰了营养物质从血浆中向血管周围邻接的组织和细胞扩散。

14 entirely   

ad.全部地，完整地；完全地，彻底地

参考例句：

• The fire was entirely caused by their neglect of duty. 那场火灾完全是由于他们失职而引起的。
• His life was entirely given up to the educational work. 他的一生统统献给了教育工作。

15 cholesterol   

n.（U）胆固醇

参考例句：

• There is cholesterol in the cell of body.人体细胞里有胆固醇。
• They are determining the serum-protein and cholesterol levels.他们正在测定血清蛋白和胆固醇的浓度。

16 differentiate   

vi.(between)区分；vt.区别；使不同

参考例句：

• You can differentiate between the houses by the shape of their chimneys.你可以凭借烟囱形状的不同来区分这两幢房子。
• He never learned to differentiate between good and evil.他从未学会分辨善恶。

17 upwards   

adv.向上，在更高处...以上

参考例句：

• The trend of prices is still upwards.物价的趋向是仍在上涨。
• The smoke rose straight upwards.烟一直向上升。

18 helping   

n.食物的一份&adj.帮助人的，辅助的

参考例句：

• The poor children regularly pony up for a second helping of my hamburger. 那些可怜的孩子们总是要求我把我的汉堡包再给他们一份。
• By doing this, they may at times be helping to restore competition. 这样一来, 他在某些时候,有助于竞争的加强。