VOA: New blood test to help doctors identify Alzheimer's disease

New blood tests could help to identify, or diagnose, Alzheimer’s disease faster and with more accuracy, researchers reported recently. However, some of the tests for the brain-wasting disease appear to work better than others.

新的血液检测可以帮助更快、更准确地识别或诊断阿尔茨海默病，研究人员最近报告说。然而，一些针对这种脑部消耗性疾病的检测似乎比其他检测效果更好。

New tests, new drugs

新的检测，新的药物

Doctors can confirm Alzheimer’s in a patient if they find one of the disease’s main signs: the development, or buildup, of a sticky protein called beta-amyloid. Currently, doctors use brain imaging or a special test known as a spinal tap to look for beta-amyloid buildup. Brain imaging is hard to get and spinal taps are painful.

如果医生发现阿尔茨海默病的主要症状之一：一种叫做β-淀粉样蛋白的粘性蛋白的发展或积聚，就可以确诊患者患有阿尔茨海默病。目前，医生使用脑成像或一种称为脊髓穿刺的特殊测试来寻找β-淀粉样蛋白的积聚。脑成像很难获得，而且脊髓穿刺很痛苦。

Instead, many patients are diagnosed based on their behavior and cognitive exams.

相反，许多患者是根据他们的行为和认知检查来诊断的。

Now, labs have begun offering blood tests that can show some signs of Alzheimer’s. Scientists are excited about the possibilities that the tests offer.

现在，实验室已经开始提供血液检测，可以显示出阿尔茨海默病的一些迹象。科学家们对这些检测提供的可能性感到兴奋。

But the tests are not widely used yet because there is little data to guide doctors about which kind to order and when. The U.S. Food and Drug Administration (FDA) has not officially approved any of them, and few patients have insurance coverage for such tests.

但这些检测还没有被广泛使用，因为几乎没有数据可以指导医生应该在什么时候订购哪种检测。美国食品和药物管理局（FDA）还没有正式批准其中任何一种检测，而且很少有患者的保险涵盖此类检测。

“What tests can we trust?” asked Dr. Suzanne Schindler of Washington University in St. Louis. Schindler is part of a research project examining the tests. While some tests are very accurate, Schindler said, “other tests are not much better than a flip of a coin.”

“我们可以相信哪些检测？”圣路易斯华盛顿大学的苏珊娜·辛德勒博士问道。辛德勒是一个研究这些检测的研究项目的一部分。辛德勒说，虽然有些检测非常准确，“但其他检测并不比抛硬币好多少”。

More than 6 million people in the United States and millions more around the world have Alzheimer’s, the most common form of dementia. Its usual signs, or “biomarkers,” are amyloid plaques and abnormal tau protein that leads to tangles that damage neurons.

美国有600多万人，全世界还有数百万人患有阿尔茨海默病，这是最常见的痴呆症。它通常的症状，或“生物标志物”，是淀粉样蛋白斑块和异常的tau蛋白，导致缠结，损害神经元。

New drugs such as Leqembi and Kisunla can slow the disease a little. The medicines remove amyloid from the brain. But these drugs only work in the early part, or stage, of Alzheimer’s progression. Few patients get the costly brain scans and invasive spinal taps that could show early stage Alzheimer’s.

像Leqembi和Kisunla这样的新药可以稍微延缓病情。这些药物可以清除大脑中的淀粉样蛋白。但这些药物只在阿尔茨海默病进展的早期或阶段起作用。很少有患者会接受昂贵的脑部扫描和侵入性脊髓穿刺，而这些检查可以显示出阿尔茨海默病的早期阶段。

Even specialists struggle to tell if Alzheimer’s or something else is to blame for a patient’s problems.

即使是专家也很难判断患者的问题是阿尔茨海默病还是其他原因造成的。

Schindler said she sometimes has patients “who I am convinced have Alzheimer’s disease and I do testing and it’s negative.”

辛德勒说，她有时会遇到一些病人，“我确信他们患有阿尔茨海默病，我做了检测，结果是阴性”。

A limited number of doctors have carried out blood tests for Alzheimer’s in carefully controlled research settings. However, a new study of about 1,200 patients in Sweden shows they also can work in doctors’ offices.

少数医生在严格控制的研究环境中对阿尔茨海默病进行了血液检测。然而，一项对瑞典约1200名患者的新研究表明，它们也可以在医生的办公室里进行。

The findings suggest the blood tests may be more helpful for general care doctors. They see many more cases of people with memory problems than specialists do. However, general care doctors have fewer diagnostic tools.

研究结果表明，血液检测可能对普通护理医生更有帮助。与专家相比，他们接触到的记忆力有问题的人要多得多。然而，普通护理医生的诊断工具较少。

In the study, patients who visited either a general care doctor or a specialist for memory problems got an early diagnosis using traditional exams. They gave blood for testing and got confirmatory spinal taps or brain scans.

在这项研究中，因记忆问题去看普通护理医生或专家的患者使用传统的检查方法获得了早期诊断。他们献血进行检测，并接受了验证性的脊髓穿刺或脑部扫描。

Blood testing is far more accurate, Lund University researchers reported recently at the Alzheimer’s Association International Conference in Philadelphia. They said that the primary care doctors’ first diagnosis was 61 percent accurate and the specialists’ first diagnosis 73 percent. However, the blood test was 91 percent accurate, their study showed. The Journal of the American Medical Association published the study.

隆德大学的研究人员最近在费城举行的阿尔茨海默病协会国际会议上报告说，血液检测要准确得多。他们说，初级保健医生的首次诊断准确率为61%，专家的首次诊断准确率为73%。然而，他们的研究表明，血液检测的准确率为91%。《美国医学会杂志》发表了这项研究。

Different biomarkers

不同的生物标志物

Dr. John Hsiao of the National Institute on Aging said the new tests measure different biomarkers in different ways.

美国国家老龄化研究所的约翰·肖博士说，新的检测方法以不同的方式测量不同的生物标志物。

Doctors and researchers should only use blood tests proven to have a greater than 90 percent accuracy rate, said Alzheimer’s Association chief science officer Maria Carrillo.

阿尔茨海默病协会首席科学官玛丽亚·卡里略说，医生和研究人员应该只使用准确率被证明超过90%的血液检测。

Carrillo and Hsiao agreed that the blood tests most likely to provide that accuracy measure what is called p-tau217. Schindler helped lead an unusual direct comparison of several kinds of blood tests that came to the same finding. The Foundation for the National Institutes of Health financed the work.

卡里略和肖一致认为，最有可能提供这种准确性的血液检测测量的是所谓的p-tau217。辛德勒帮助领导了一项不同寻常的直接比较几种血液检测的工作，得出了同样的发现。美国国立卫生研究院基金会资助了这项工作。

That kind of test measures a form of tau that correlates with how much plaque buildup someone has, Schindler explained. A high level signals a strong likelihood the person has Alzheimer’s. A low level strongly suggests Alzheimer’s is not the cause of a patient’s thinking problems.

辛德勒解释说，这种检测方法测量的是一种与患者斑块积聚量相关的tau蛋白形式。高水平表明该人很有可能患有阿尔茨海默病。低水平强烈表明阿尔茨海默病不是患者思维问题的根源。

Several companies are developing p-tau217 tests.

几家公司正在开发p-tau217检测。

Who should use blood tests for Alzheimer’s?

谁应该使用阿尔茨海默病血液检测？

In the United States, only doctors can order the blood tests from labs. The Alzheimer’s Association is working on policy suggestions and several companies plan to seek FDA approval, which would clarify correct use.

在美国，只有医生才能从实验室订购血液检测。阿尔茨海默病协会正在制定政策建议，几家公司计划寻求FDA的批准，这将阐明正确的使用方法。

For now, Carrillo said doctors should use blood testing only in people with memory problems, after checking the accuracy of the kind they order.

卡里略说，就目前而言，医生应该只对有记忆问题的人进行血液检测，并在检查了他们所订购的血液检测的准确性之后。

Especially for primary care physicians, “it really has great potential to help them in sorting out who to give a reassuring message and who to send on to memory specialists,” said Dr. Sebastian Palmqvist of Lund University. Palmqvist led the Swedish study with Lund’s Dr. Oskar Hansson.

隆德大学的塞巴斯蒂安·帕尔姆克维斯特博士说：“特别是对初级保健医生来说，它真的有很大的潜力帮助他们区分哪些人可以得到安慰的信息，哪些人需要转诊给记忆专家。”帕尔姆克维斯特与隆德大学的奥斯卡·汉森博士共同领导了这项瑞典研究。

I’m John Russell.

我是约翰·拉塞尔。

And I’m Caty Weaver.

我是凯蒂·韦弗。

diagnose – v. to identify a disease from its signs and symptoms

diagnosis – n. the act of identifying a disease from its signs and symptoms

accuracy – n. the quality of being precise or correct

cognitive – adj. of or relating to thinking, reasoning, or remembering

neuron – n. a cell that is the fundamental functional unit of nervous tissue transmitting and receiving nerve impulses

correlate – v. to bear mutual relations