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  • Researchers are investigating if a finger prick blood test could be used to detect Alzheimer’s disease earlier than with traditional methods.
  • Researchers looked at 77 people with Alzheimer’s disease.
  • They found that they could detect key biomarkers via a finger prick blood test.

A simple, finger prick blood test may be used in the future to help diagnose Alzheimer’s disease more quickly than current methods.

According to research presented at the Alzheimer’s Association International Conference in Amsterdam, advancements in technology are showing the potential for ease and accuracy of blood-based biomarkers for Alzheimer’s, including the future potential for at-home testing by a patient or family member.

“Diagnosing Alzheimer’s early in the disease course is notoriously difficult, particularly in high-functioning individuals,” said Dr. Gayatri Devi, a neurologist at Northwell Lenox Hill Hospital. “The majority of early and mild cases of Alzheimer’s remain clinically undiagnosed, and therefore untreated — a true lost opportunity to make a difference in prognosis. Having early access to blood tests that can accurately diagnose the condition very early using biomarkers is a groundbreaking advance.”

Physicians conduct a variety of tests to assess memory impairment and thinking skills. These tests may include laboratory tests via blood draws or brain imaging tests such as MRIs.

There is no one single test that can diagnose Alzheimer’s disease.

“Due to the lack of accurate diagnostic tools, it is currently very difficult for primary care doctors to identify Alzheimer’s disease, even among patients with cognitive impairment,” Dr. Sebastian Palmqvist of the Clinical Memory Research Unit at Lund University, Sweden said in a statement. “This too often leads to diagnostic uncertainty and inappropriate treatment. Blood tests for Alzheimer’s disease have great potential for improving diagnostic accuracy and proper treatment of people with Alzheimer’s. These tests may become even more important in the near future, as new drugs that slow down the disease in its early stages become more widely available.”

Palmqvist conducted a separate study to examine the use of blood-based biomarkers for Alzheimer’s in primary care, comparing them with the diagnostic accuracy of primary care physicians using cognitive tests and brain imaging. The use of blood-based biomarkers was found to have higher accuracy for diagnosing Alzheimer’s.

The researchers behind this latest study had the goal to simplify and increase the accessibility of blood tests by developing a finger prick test to measure Alzheimer’s-related biomarkers Neuro-filament light (NfL), glial fibrillary acidic protein (GFAP), and phosphorylated tau (p-tau 181 and 217).

Currently, some blood tests are already being used, mainly in Alzheimer’s drug trials for further verification of their effectiveness. This provides a more cost-effective, and less invasive, solution than the current tests.

In the new study, researchers collected blood from 77 patients from the ACE Alzheimer Center, Barcelona. The blood samples were measured for their NfL, GFAP, and p-tau 181 and 217.

All were detectable in the finger prick samples.

Hanna Huber, Ph.D., of the Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, University of Gothenburg, Sweden, said that more research will need to be done to verify these early findings.

“Our pilot study demonstrates the potential of remote collection and measurement of Alzheimer’s biomarkers without low-temperature storage or extraordinary preparation or processing,” Huber said in a statement. “Currently, use of Alzheimer’s blood tests is limited by the need to visit a clinic, administration by trained personnel, and strict time-limited and temperature-dependent delivery and storage procedures. A method that allows blood collection at home and that is simple enough to be performed independently, or by caregivers, would increase accessibility of these tests. It would result in improved early diagnosis and better monitoring of patients considered ‘at risk’ or those who are receiving approved therapies.”

Dr. Thomas Wisniewski, director of the NYU Langone Alzheimer’s Disease Research Center, said this pilot study shows how these tests may be useful in the future.

“These tests have pretty good sensitivity and specificity,” said Wisniewski. “It’s not quite there for clinical use and getting FDA approval, but it’s getting closer. There is an immediate, clear need to have a much less expensive and more readily available plasma biomarker for Alzheimer’s positivity. We’re not quite there yet, but I think we will be in the very much foreseeable future.”

Alzheimer’s is a brain disease that eventually leads to a decline in memory, thinking, and reasoning skills. According to the Alzheimer’s Association, there are 10 warning signs and symptoms. These include:

  • Memory loss that disrupts daily life.
  • Challenges in planning or solving problems.
  • Difficult completing familiar tasks.
  • Confusion with time or place.
  • Trouble understanding visual images and spatial relationships.
  • New problems with words in speaking or writing.
  • Misplacing things and losing the ability to retrace steps.
  • Decreased or poor judgment.
  • Withdrawal from work or social activities.
  • Changes in mood and personality.

The Alzheimer’s Association notes that if you or someone you know experiences one or more signs, it is a good idea to consult with your doctor. The hope is that, sometime in the future, these blood tests can make it even easier and more affordable for doctors to screen for Alzheimer’s.

While experts agree that the blood detection of Alzheimer’s will revolutionize the diagnosis and treatment of the disease, they also agree that we are not quite there yet. More research still has to be done before this method is adopted in widespread practice.

“There needs to be testing in multiple populations that are more diverse, and [in] larger numbers,” said Wisniewski. “For example, this testing was done in quite small numbers in an academic setting. That is not at all representative of what one would see in a community-based setting. These plasma biomarkers need to be tested firstly in larger numbers, but also in more diverse populations and in non-academic settings.”

In a pilot study, researchers found that a finger prick test could accurately detect key biomarkers of Alzheimer’s disease.