Blood Test Method May Predict Amyloid Deposits In Brain Potentially Indicating Alzheimer’s Disease
A number of research projects are underway to develop a sensitive blood test that could help screen people for Alzheimers disease in a less invasive and costly way than current imaging and biomarker tests. NIA-supported researchers at Washington University in St. Louis reported an advance Aug. 1 in Neurology for their method of detecting amyloid protein in blood. The researchers are validating the method by showing an association between blood levels of amyloid and results from conventional biomarker tests for Alzheimers.
Using a technique called immunoprecipitation mass spectrometry, the research team developed a precise method for quantifying how much beta-amyloid 42 and beta-amyloid 40 are in a sample of blood. Previous studies have suggested that the ratio of these two forms of beta-amyloid may correspond with amyloid in the brain.
Next, the researchers analyzed the blood of 158 adults , most without dementia symptoms, using their sensitive method, and evaluated them with positron emission tomography imaging and cerebrospinal fluid tests. The researchers found that the ratio of beta-amyloid 42 and beta-amyloid 40 in blood was associated with the detection of amyloid by PET scans and cerebrospinal fluid tests.
This research was funded in part by NIA grants R56AG061900, P01AG026276, P01AG03991, P50AG05681, K23AG053426, and K01AG053474.
A Blood Test For Alzheimer’s Markers For Tau Take Us A Step Closer
CHICAGO, JULY 28, 2020 A simple blood test for Alzheimerâs would be a great advance for individuals with â and at risk for â the disease, families, doctors and researchers.
At the Alzheimerâs Association International Conference® 2020, scientists reported results of multiple studies on advances in blood âtestsâ for abnormal versions of the tau protein, one of which may be able to detect changes in the brain 20 years before dementia symptoms occur. In particular, the reports focus on a specific form of tau known as p-tau217, which seems to be the most specific to Alzheimerâs and the earliest to show measurable changes.
Changes in brain proteins amyloid and tau, and their formation into clumps known as plaques and tangles, respectively, are defining physical features of Alzheimerâs disease in the brain. Buildup of tau tangles is thought to correlate closely with cognitive decline. In these newly reported results, blood/plasma levels of p-tau 217, one of the forms of tau found in tangles, also seem to correlate closely with buildup of amyloid.
Currently, the brain changes that occur before Alzheimerâs dementia symptoms appear can only be reliably assessed by positron-emission tomography scans, and from measuring amyloid and tau proteins in spinal fluid . These methods are expensive and invasive. And, too often, they are unavailable because they are not covered by insurance or difficult to access, or both.
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Using Blood Tests And Psychological Tests To Predict Familial Alzheimers Disease Using Blood Tests And Psychological Tests To Predict Familial Alzheimers Disease
Research project: Accessible biomarkers of progression and prognosis: a multimodal study of familial Alzheimer’s disease
Lead Investigator: Dr Antoinette OConnor
- Institution: Institute of Neurology, University College London
- Grant type: Clinical Training Fellowship
- Duration: 36 months
Comments from our Research Network volunteers:
A simple blood test would be a big step forward – less intrusive, quicker and cheaper for the NHS.’
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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.
Recruitment Of Participants And Neuroimaging
Participants were recruited as part of the Korean Brain Aging Study for the Early diagnosis and prediction of Alzheimers disease project. One hundred forty-nine participants with cognitively normal , 87 patients with MCI, and 64 patients with clinically diagnosed AD DEM were included in this study . They all underwent PiB-PET neuroimaging through a 3.0T positron emission tomographymagnetic resonance imaging scanner. A total of 555 MBq of PiB was intravenously administered. To calculate the degree of cerebral amyloid deposition , four regions of interest were defined by an automatic anatomic algorithm and a region-combining method as follows: frontal, lateral parietal, posterior cingulate-precuneus, and lateral temporal regions. The standardized uptake value ratio of each ROI was a criterion for PiB-PET positivity . Furthermore, all participants were given comprehensive clinical and neuropsychological assessments according to the KBASE baseline assessment protocol. Detailed information on the methodology and baseline sample characteristics as described in our previous paper.
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See The Hunt For A Blood Test For Alzheimers Disease
The C2N test relies on the ratio of two isoforms of the amyloid- protein, A42 and A40, that aggregate to form amyloid plaques in the brain, combined with the presence of isoforms of apolipoprotein E that reflect whether the patient caries a genetic variant associated with Alzheimers risk. The results are combined into a score that indicates the probability that a patient would be found to have amyloid plaques if they were to undergo an amyloid PET scan. Doctors can then consider the test results along with other information about the patient to arrive at a diagnosis. According to data posted on the companys website, a study in 686 patients with cognitive impairment found that those with scores above a certain cutoff point had a positive amyloid PET scan 92 percent of the time, while those with scores below a certain cutoff had a 77 percent chance of having a negative result on the PET scan.
While no drugs have yet been approved to treat Alzheimers, being able to distinguish it from other possible causes of cognitive impairment is nonetheless valuable, Fillit and Schindler say. As a clinician, Schindler says, I want to know what my patients have. That can be complicated because in many cases, they dont just have memory impairment, theyre taking multiple medications, they have all sorts of health issues, she says. And sometimes its really hard to know whether the symptoms theyre experiencing are due to something like Alzheimers or something else.
Leakage From Brain Can Be A Sign Of The Disease Long Before Cognitive Symptoms Emerge
by Kent Allen, AARP, January 23, 2019
Science Photo Library/Alamy
En español | A simple blood test for a protein identified with Alzheimers disease could help identify those who have the illness in its earliest stages, well before apparent signs of it emerge, although the protein is also identified with other neurological issues.
Key to the test is the presence of the neurofilament light chain protein . It is contained in neurons in the brain. But damaged cells leak NfL, which ultimately enters the bloodstream. Researchers say detection of NfL in the blood could be made years before symptoms like memory loss or confusion are seen in Alzheimers patients.
Researchers from Washington University in St. Louis and the German Center for Neurodegenerative Diseases published a letter on their study in a recent issue of the medical journal Nature Medicine.
For their study, researchers relied on families that may carry a rare inherited genetic variant that can cause Alzheimers earlier than average, when people are in their 40s or 50s. The researchers studied more than 400 people from such families, of whom 247 carried the variant. In those with the mutation, levels of NfL in the blood were high at the start of the research and rose over time. Among those who didnt carry the variant, the protein level was low and stayed that way.
The difference in such levels can be detected 16 years before cognitive symptoms were expected to arise, the researchers found.
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Detecting Alzheimers Gets Easier With A Simple Blood Test
New assays could reduce the need for costlier, more invasive brain scans and spinal fluid measures
When a patient complains of forgetfulness, a neurologist might not know immediately whether it results from normal aging, reduced blood flow to the brainor, more ominously, Alzheimers disease. For much of the past century, a definitive Alzheimers diagnosis could only be made during an autopsy. Brain imaging and spinal fluid tests now make it possible to spot the disease in patients even before the initial symptoms appear. But these invasive tests are expensive and generally limited to research settings that are not part of routine care for the millions of people suffering from the most common neurodegenerative disorder.
An era in which an Alzheimers diagnosis can begin in a doctors office is now arriving. Advances in technologies to detect early signs of disease from a blood sample are helping doctors to identify the memory-robbing disorder more accurately and to screen participants more quickly for trials of potential treatments for the more than five million people in the U.S. afflicted with Alzheimers.
The development of a blood-based test for Alzheimers disease is just phenomenal, says Michelle Mielke, a neuroscientist and epidemiologist at the Mayo Clinic. The field has been thinking about this for a very long time. Its really been in the last couple of years that the possibility has come to fruition.
Blood Test For Alzheimers Highly Accurate In Large International Study
When combined with genetic risk factors, test up to 93% accurate at identifying people at risk of Alzheimer’s dementia
Neurologist Randall J. Bateman, MD, the Charles F. and Joanne Knight Distinguished Professor of Neurology, inspects a mass spectrometry machine at Washington University School of Medicine in St. Louis. Using mass spectrometry, Bateman and colleagues have developed a blood test that is up to 93% accurate at identifying people at risk of Alzheimer’s dementia.
A blood test developed at Washington University School of Medicine in St. Louis has proven highly accurate in detecting early signs of Alzheimers disease in a study involving nearly 500 patients from across three continents, providing further evidence that the test should be considered for routine screening and diagnosis.
The study is available in the journal Neurology.
Our study shows that the blood test provides a robust measure for detecting amyloid plaques associated with Alzheimers disease, even among patients not yet experiencing cognitive declines, said senior author Randall J. Bateman, MD, the Charles F. and Joanne Knight Distinguished Professor of Neurology.
Developed by Bateman and colleagues, the blood test assesses whether amyloid plaques have begun accumulating in the brain based on the ratio of the levels of the amyloid beta proteins A42 and A40 in the blood.
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Blood Test Can Predict Alzheimers Disease
A blood test that can predict with 90 per cent accuracy if a healthy person will develop mild cognitive impairment or Alzheimers disease within three years has been discovered and validated by researchers at Georgetown University and six other institutions.
The study team explains in the April issue of Nature Medicine how they discovered and then validated a set of 10 lipid biomarkers in the blood that predict both conditions.
The discovery heralds the possible development of earlier treatment options for Alzheimers, when therapy could be more effective at slowing or even preventing onset of the disease.
Our novel blood test offers the potential to identify people at risk for progressive cognitive decline and can change how patients, their families and treating physicians plan for and manage the disorder, says the studys corresponding author, Dr. Howard J. Federoff, executive vice president of health sciences at Georgetown University Medical Center.
There is currently no cure or effective treatment for Alzheimers disease, which, according to the World Health Organization, is expected to double every 20 years worldwide from 35.6 million individuals in 2010 to 115.4 million by 2050.
Federoff, also a professor of neurology, explains there have been many efforts to develop drugs to slow or reverse the progression of Alzheimers disease, but all of them have failed. He says one reason may be the drugs were evaluated too late in the disease process.
Major Step Forward
Simple Diagnostic Tool Predicts Individual Risk Of Alzheimer’s
- Date:
- Lund University
- Summary:
- Researchers at Lund University in Sweden have developed an algorithm that combines data from a simple blood test and brief memory tests, to predict with great accuracy who will develop Alzheimer’s disease in the future. The findings are published in Nature Medicine.
Researchers at Lund University in Sweden have developed an algorithm that combines data from a simple blood test and brief memory tests, to predict with great accuracy who will develop Alzheimer’s disease in the future. The findings are published in Nature Medicine.
Approximately 20-30% of patients with Alzheimer’s disease are wrongly diagnosed within specialist healthcare, and diagnostic work-up is even more difficult in primary care. Accuracy can be significantly improved by measuring the proteins tau and beta-amyloid via a spinal fluid sample, or PET scan. However, those methods are expensive and only available at a relatively few specialized memory clinics worldwide. Early and accurate diagnosis of AD is becoming even more important, as new drugs that slow down the progression of the disease will hopefully soon become available.
One clear advantage of the algorithm is that it has been developed for use in clinics without access to advanced diagnostic instruments. In the future, the algorithm might therefore make a major difference in the diagnosis of Alzheimer’s within primary healthcare.
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Summary Of Test And Benefits
Knowing that your symptoms are due to Alzheimers can help inform your healthcare provider to prescribe specific Alzheimers treatments in order to aid in the management of the disease. If your symptoms are unlikely due to Alzheimers , your healthcare provider can search for other causes, some of which can be treated with different interventions.
Earlier detection provides the opportunity for earlier care options, including clinical trials. Many clinical trials for Alzheimers disease are looking for participants who show initial signs of cognitive impairment. You also may be eligible to enroll in clinical trials as a result of the PrecivityAD test results.
Researchers at CN Diagnostics have found the PrecivityAD test results to be an accurate indicator of Alzheimers disease pathology among people with memory and thinking issues. The PrecivityAD test is easy to administer, does not involve any radiation, and is non-invasive. These features make it more accessible than other diagnostic methods doctors use to evaluate issues with memory and thinking.
Blood Test May Predict Progression To Alzheimers Disease Say Researchers
A blood test for 10 protein biomarkers in people with mild cognitive impairment can predict who will develop Alzheimers disease over the following year with a high degree of accuracy, a new study has claimed.1
Abdul Hye, lead author and a researcher at Kings College, London, said, There are thousands of proteins in the blood, and this study is the culmination of many years work identifying which ones are clinically relevant. We now have a set of 10 proteins that can predict whether someone with early symptoms of memory loss, or mild cognitive impairment, will develop Alzheimers disease within a year, with a high level of accuracy.2
The secretary of state for health, Jeremy Hunt, released a statement saying, This is welcome research on
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Blood Test For Alzheimer’s
The First Blood Test Able to Diagnose Alzheimer’s
Researchers announced this past week that they have developed a blood test capable of diagnosing Alzheimers disease. The blood test uses a complex form of analysis to calculate the amount of Amyloid and Tau in the blood.
Amyloid and Tau are the two abnormal proteins believed to be the primary cause of Alzheimers disease.
Depending upon the levels of Amyloid and Tau detected, the test can determine with 90% accuracy whether or not an individual has Alzheimers disease.
Previous tests which analyzed levels of Amyloid and Tau were either prohibitively expensive- often costing in excess of $5,000 USD, or invasive- requiring a sample of fluid to be taken from the spine via a procedure known as a spinal tap.
This new test, PrecivityAD offered by C2N Diagnostics, costs $1,250 USD and while it is not yet covered by insurance, C2N Diagnostics plans to offer price reductions based on income.
One important distinction of the PrecivityAD test, is that it is primarily a diagnostic rather than predictive test. For the test to return a diagnosis of Alzheimers, the individual being tested must have already developed Alzheimers disease- even though initial symptoms may be mild or imperceptible. This is in contrast with the ApoE Genetic Test, which can predict the likelihood of developing Alzheimers decades in advance.
Blood Tests Predicting Alzheimer’s Disease
Researchers from Georgetown University Medical Center claim to have developed a blood test capable of predicting whether a person will develop Alzheimers disease. They found that some biomarkers in the blood could be used to predict whether a person would develop Alzheimers disease within three years – with 90% accuracy.
The researchers examined 525 healthy participants aged 70 and over and monitored them over a period of 5 years, regularly analyzing their blood samples. Based on the sample size, 28 of these participants went on to develop Alzheimers disease or Mild Cognitive Impairment that usually precedes AD. They compared the blood samples of those 28 people with the samples from their more cognitively stable peers, as well as with 54 individuals in the community with diagnosed Alzheimers disease or MCI. The researchers found that individuals who developed dementia had lower levels of 10 particular lipids than the healthier seniors in the group. The blood test predicted who would develop Alzheimers disease or MCI with 90% accuracy.
If the test gets approved, it would potentially help detect Alzheimer’s disease before a person experienced symptoms. This would widen the window of opportunity for treatment of Alzheimer’s disease, and the medications may have greater efficacy during the early stages. Moreover, it would give people more time to do some of the things on their bucket list and plan for their future.
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