Future Screening In Primary Care
The blood test developed at the University of Gothenburg produces results similar to those from the blood test that was developed at the U.S. pharmaceutical company Eli Lilly. Results from the latter were recently published in Nature Medicine, with Kaj Blennow and Henrik Zetterberg as coauthors.
We believe that, in the future, one very important use of our blood test will be for screening in primary care. We demonstrated this in one of the studies forming part of our article, in which we looked at patients in primary care with concerns about their failing memory, Blennow says .
We also think the level of P-tau181 in blood plasma may be a very important marker to show and monitor the efficacy of the new drugs against Alzheimers that are currently being developed, says Henrik Zetterberg .
Previous studies:
A Better Alzheimers Test
The abnormalities in the brains of Alzheimers patients amyloid plaques and tau tangles begin forming two decades or more before people begin experiencing symptoms.
Until now, without a brain scan or spinal tap, there was no way to know this was happening.
Until now, without a brain scan or spinal tap, there was no way to know this was happening.
A Lund University-led research team discovered that it could predict the presence of both plaques and tangles in a persons brain by measuring the amount of one specific tau protein in their blood.
For a study published in the Journal of the American Medical Association, the researchers evaluated the accuracy of their blood test for Alzheimers on 1,402 people.
They found that it was more accurate than MRI scans at detecting the disease and as accurate as PET scans and spinal taps. The only method more accurate is the only one that can definitively diagnose Alzheimers: a brain autopsy.
High Sensitivity And Precision
P-tau181 has long been measurable through testing of cerebrospinal fluid, in which it is found at a considerably higher level than in blood samples. For the past few years, it has also been possible to demonstrate neurofibrils by using the advanced positron emission tomography medical imaging technique. Tests of cerebrospinal fluid are, however, difficult to perform in primary care, and the high costs of PET scans restrict their use. Being able to establish tau pathology through ordinary blood tests will, therefore, be highly valuable.
The results now published show that the level of P-tau181 is greatly elevated in Alzheimers, including at its early stage, known as mild cognitive impairment. However, this raised level was found only in the patients who also had amyloid plaques, as revealed by the PET camera.
The level of specific P-tau181 in blood plasma also proved to correspond very closely with the level of tau tangles in the brain registered with the PET-technique. The blood test also identified people early on in the course of the disease who had plaques, but in whom the PET technique discerned no increased tau levels.
The blood test showed a very good capacity to distinguish Alzheimers from other brain diseases, such as frontotemporal dementia and Parkinsons disease, where the blood level of P-tau181 was entirely normal.
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New Blood Test May Accurately Detect Alzheimers Disease
A large-scale international study shows that a new blood test can accurately detect markers of Alzheimers disease. Pansfun Images/Stocksy Brain imaging and spinal fluid tests are two of the most common ways scientists detect early signs of Alzheimers disease in people. However, some of these tests are expensive, invasive, and not routinely available to the millions of individuals who may be at risk of this neurodegenerative condition.
Now, a blood test developed by researchers at Washington University School of Medicine, St. Louis, has shown promising results in detecting the early signs of AD. Randall Bateman, M.D. the Charles F. and Joanne Knight Distinguished Professor of Neurology and colleagues set out to determine the diagnostic accuracy of a new blood test for detecting early signs of AD.
AD occurs due to the accumulation of beta-amyloidTrusted Source, a protein that clumps together to form sticky plaques on the brain.
These plaques affect the transmission of brain cell signals and may result in the death of brain cells, leading to symptoms of AD. These symptoms include memory loss, mood changes, and difficulties with speech. Two of the most problematic proteins are beta-amyloid 40 and beta-amyloid 42 because health experts believe they contribute the most to the creation of sticky plaque.
They then looked at the formation of beta-amyloid 42 and how it traveled from the brain into the blood.
How Could An Earlier Diagnosis Of Alzheimers Affect The Treatment And Care Of Patients
Kanaan: Early detection of Alzheimers disease and other dementias is a critical factor in furthering our understanding of disease etiology and progression. Indeed, identifying a disease like Alzheimers accurately and early, before significant cognitive decline occurs, could provide a therapeutic window in which administration of future therapeutics could slow or stop the disease.
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Blood Tests For Dementia Alzheimers A New Way To Diagnosis These Diseases
Scientists have been working for decades on developing new methods that would accurately detect signs and symptoms of Alzheimers disease. Prior to the early 2000s, the only way to know for sure whether a person had Alzheimers was to conduct an autopsy after the individual died, according to the National Institute of Aging.
Now, researchers believe a new generation of blood tests can more accurately diagnose Alzheimers, a brain disease that slowly worsens over time and causes memory loss and other cognitive problems.
More than 6 million people in the United States are living with Alzheimers, which is the most common cause of dementia, according to the Alzheimers Association. Alzheimers has no cure, but treatment can slow the progression of the disease.
Stephen Salloway, a professor of neurology and psychiatry at Brown University who directs a memory and aging program at Butler Hospital in Providence, Rhode Island, says the new blood tests represent a very early start to a new era of diagnosis for Alzheimers disease.
Scientists say that blood tests are not as expensive or invasive as brain imaging, spinal fluid tests, and other methods used to determine signs and symptoms of Alzheimers. A blood test might also be more practical for people who do not have access to memory clinics or specialists who can diagnose Alzheimers disease.
In addition to a PET scan or spinal tap, doctors diagnose Alzheimers disease by using other methods that include:
New Blood Test May Predict Alzheimers Disease
A new blood testing technique could help researchers detect Alzheimers disease before symptoms start or in its early stages.
Alzheimers disease is an age-related brain disorder that develops over many years. Toxic changes in the brain slowly destroy memory and thinking skills.
The disease involves two proteins called beta-amyloid and tau. Beta-amyloid clumps into plaques, which slowly build up between brain cells. Abnormal tau collects inside brain cells and forms tangles.
Researchers investigated whether a new blood testing technique could help predict development of Alzheimers disease. They tested for a modified version of tau called ptau181 in blood plasma . Levels of this protein have been linked with Alzheimers disease.
The team collected blood samples from more than 400 people. The analysis showed that ptau181 levels differed between healthy participants and those with Alzheimers disease.
The new approach could be less invasive and costly than current tests for Alzheimers disease. These rely on brain scans and lab tests of spinal fluid.
The development of a blood test would enable us to rapidly screen a much larger and more diverse group of volunteers who wish to enroll in studies, says Dr. Richard J. Hodes, director of NIHs National Institute on Aging.
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How Is Alzheimers Disease Usually Detected
Paulson: Doctors usually make a clinical diagnosis of Alzheimers disease based on the history of the illness, cognitive assessment, a neurologic examination and often standard brain imaging. It is an imperfect science and we are not always right in concluding that the diagnosis is Alzheimers rather than some other form of dementia.
Testing the cerebrospinal fluid for biomarkers of Alzheimers can lead to a more precise diagnosis, but many patients are not eager to undergo the spinal tap needed to get this answer, and sometimes insurance companies wont pay for the test.
New imaging methods allow is to visualize the key Alzheimers proteins in the brain, namely beta-amyloid and tau, but these imaging procedures are expensive and not yet covered by insurance.
Blood Test Could Bring New Hope To Alzheimers Clinical Trials
19 January 2021
A team of scientists at UCL have found that blood tests measuring the hallmark Alzheimers protein, b-amyloid , could radically reduce the cost of clinical trials and potentially open the door to treating the disease earlier. The scientists studied a unique group of volunteers, who were all born in the same week in 1946. The findings are published on Tuesday 19 January, in the journal Brain.
Amyloid is a protein that builds up in the brain in Alzheimers, and it is thought to set off a cascade of processes that result in damage to the brain and the symptoms of the disease. Amyloid accumulates in the brain years before symptoms appear and clearing this protein has been a major focus of Alzheimers research for the last two decades.
Most amyloid-lowering drug trials so far involve people who already have symptoms an approach that has yet to result in a new treatment. Many researchers believe that by the time symptoms set in, the window of opportunity for preventing cognitive decline may have already passed. These drugs are likely to be more effective earlier on, in people who have amyloid build-up but dont yet have symptoms.
Scientists have developed radioactive tags that attach to the amyloid protein. A PET scanner can pick up the radiation from these tags to reveal the extent of amyloid build up in a persons brain.
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Minimally Invasive Blood Test For Alzheimers Disease Announced
- Minimally invasive blood test for Alzheimers disease announced
Scientists from Japan and Australia have teamed up to develop and validate a blood test for Alzheimers disease, with the potential to massively ramp up the pace of Alzheimers disease drug trials.
The blood test measures a specific peptide in the blood to inform scientists, with 90 per cent accuracy, if a patient has the very earliest stages of Alzheimers disease.
Blood samples from patients in a large study from the Japanese National Center for Geriatrics and Gerontology were initially analysed to identify the relevant peptides. Those indicating brain beta-amyloid burden were then tested against patient samples from the Australian Imaging, Biomarker and Lifestyle Study of Aging , to validate the results.
Professor Katsuhiko Yanagisawa, Director-general of Research Institute at NCGG, says: Our study demonstrates the high accuracy, reliability and reproducibility of this blood test, as it was successfully validated in two independent large datasets from Japan and Australia.
Dr Koichi Tanaka at Shimadzu Corporation was instrumental in developing the initial blood testing procedure. Professor Tanaka won the Nobel prize in Chemistry in 2002 for the technique. From a tiny blood sample, our method can measure several amyloid-related proteins, even though their concentration is extremely low. We found that the ratio of these proteins was an accurate surrogate for brain amyloid burden.
Potential New Blood Test In Alzheimers Disease Could Advance Treatment
Experts describe a method that could be used to spot the complex brain disease.
Since its discovery, Alzheimers disease has been a challenge to test for and predict in patients. Currently, testing is primarily done through brain imaging and behavioral tests, which are costly and often fail to detect the disease in its earliest stages.
However, research presented at the last Alzheimers Association International Conference show a promising blood test that may detect Alzheimers before symptoms appear, in an affordable and accessible manner.
Henry Paulson, M.D., Ph.D, professor of neurology and director of the Michigan Alzheimers Disease Center andNicholas M. Kanaan, Ph.D., associate professor of translational neuroscience at Michigan State University, joined forces to share their opinions on what this development could mean for the future of Alzheimers testing. Paulson directs the statewide Michigan Alzheimers Disease Research Center, while Kanaan leads the centers biomarker core.
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Studies Show New Blood Tests Work In Diagnosing Alzheimers
Scientists at Washington University School of Medicine, St. Louis, developed a blood test for Alzheimers disease that they say is an alternative to expensive imaging tests, such as the PET scan which can average $5,000 to $8,000 per scan.
The research teams study, which involved nearly 500 people from across three continents, estimates that prescreening for the disease with a $500 blood test is more affordable than brain scans and other expensive tests.
A blood test for Alzheimers provides a huge boost for Alzheimers research and diagnosis, drastically cutting the time and cost of identifying patients for clinical trials and spurring the development of new treatment options, Dr. Randall J. Bateman, the studys senior author and the Charles F. and Joanne Knight Distinguished Professor of Neurology, said in a statement about the study, published in February in the journal Neurology.
The Washington University research team developed a blood test that determines whether amyloid plaques have started accumulating in the brain based on the ratio of the levels of the amyloid beta proteins in the blood. The study showed the blood tests accuracy, when combined with genetic risk factors for Alzheimers dementia, was 88 percent when compared to brain imaging and 93 percent when compared to spinal tap.
Besides Eli Lilly, Quest Diagnostics, a national clinical laboratory, launched a new blood test in March that measures two amyloid variants.
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Original Research: Closed accessLancet Neurology doi:10.1016/S1474-442230071-5
Abstract
Blood phosphorylated tau 181 as a biomarker for Alzheimers disease: a diagnostic performance and prediction modelling study using data from four prospective cohorts
Funding Alzheimer Drug Discovery Foundation, European Research Council, Swedish Research Council, Swedish Alzheimer Foundation, Swedish Dementia Foundation, Alzheimer Society Research Program.
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Added Benefits Of The Blood Test
MRIs and other Alzheimers diagnostic tests can be pricey. This test can improve diagnostic accuracy in an inexpensive way, Szigeti says. She adds it may also help bring peace of mind to people who are worried that they may be developing Alzheimers disease, but are actually experiencing symptoms due to another health issue.
The blood test may also help identify people who qualify for clinical trials.
“Those trials use medications that we are hoping will stop the progression of the disease, and may be more helpful for certain patients, Szigeti says.
Ultimately, the test may be more helpful with time as new treatments are developed.
With an increasing focus on prevention in developing new medications, the potential for intervening early will become very important over the next years, Paul Newhouse, MD, director of the Vanderbilt Center for Cognitive Medicine, tells Verywell. “We have been searching for some time for blood tests that would help us confirm the diagnosis of Alzheimer’s disease. If these results are confirmed, this could be a very promising new diagnostic test that would help us diagnose patients earlier than we are able to now.”
What Did The Scientists Do
The UCL team led by Prof Jonathan Schott worked with a unique group of over 400 volunteers, recruited from the Medical Research Council National Survey of Health and Development 1946 British Birth Cohort. They were all born in the same week in 1946 and did not have dementia. They had amyloid PET scans and blood tests as part of the Alzheimers Research UK-funded Insight 46 study, Blood tests were done at UCL and through collaboration with researchers at the University of Gothenburg, Sweden.
The researchers compared three different ways of measuring proteins of interest in the blood and compared the results of the blood tests to those from the PET scans.
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Blood Test Can Predict Presence Of Beta
Scientists have demonstrated that a new blood test can accurately predict the presence of beta-amyloid plaques in the brain, according to a new study funded in part by NIA. Published in Neurology, the study analyzed the ability of a blood test to predict the presence of Alzheimers disease-associated protein beta-amyloid in the brain. The new blood test, which performs comparably to existing brain scan- or spinal tap-based tests, could lower costs and expand the availability of diagnostic studies for Alzheimers disease.
Alzheimers is characterized by the buildup of a protein called beta-amyloid, which forms sticky plaques on the brain and can cause brain cells to die. Testing for the presence of these amyloid plaques on the brain is an important part of Alzheimers diagnosis and research. For people experiencing memory problems, checking for amyloid in the brain helps health care providers determine whether Alzheimers is the potential cause. It also can help doctors determine which patients will respond to drugs that target amyloid. For people without any signs of dementia, the presence of amyloid plaques on the brain may help researchers enroll participants in clinical trials for treatments to prevent or delay the onset of cognitive symptoms.
This research was supported in part by NIA grants RF1AG061900, R56AG061900, K23AG053426, 5U19AG024904-14, and 3U19AG024904-15S1.
The Use Case For A Diagnostic Test
Alzheimers disease has minimal treatment options. Currently, patients with mild to moderate Alzheimers may be prescribed medications called cholinesterase inhibitors to try to help reduce some symptoms, but the medication loses its effectiveness over time, according to the National Institute on Aging .
Patients with moderate to severe forms of the disease may be prescribed different medications, including memantine, allowing them to keep certain daily functions a little longer than they would without medication, the NIA says. Still, none of these treatments are perfect and there is currently no treatment that can cure or halt the progression of the disease.
Knowing that they could potentially diagnose Alzheimer’sbut sill not cure itwould doctors actually use this test if it were available today? The answer appears to be yes, as long as it is used to diagnose Alzheimer’s in symptomatic patients, not screen for it.
“A blood marker for Alzheimers would be get used all the time if it was specific for the disease,” Amit Sachdev, MD, director of the Division of Neuromuscular Medicine at Michigan State University, tells Verywell.
For starters, a diagnosis could help empower people who are beginning to develop symptoms of Alzheimers disease, such as memory loss and confusion.
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