Blood Test for Alzheimer's Disease

Researchers have discovered a simpler way of diagnosing Alzheimer's disease before it strikes.

An elderly couple dealing with Alzheimer's disease.

A new blood test for Alzheimer's disease has the potential to be more accessible to patients. 

By + More

Seniors now may be able to assess their risk for Alzheimer’s disease with a simple blood test, thanks to new research from Georgetown University and the University of Rochester.

“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,” said Dr. Howard Federoff, a study author and executive vice president of health sciences at Georgetown University Medical Center, in an article on the medical center's website. 

The new test can determine with 90 percent accuracy whether an older adult might develop Alzheimer’s disease within approximately three years. 

One of the most common ways for doctors to identify patients with Alzheimer’s disease is to scan their brains. Images from these scans are used to help doctors locate plaques and tangles characteristic of the disease. A second method involves extracting fluid from the spinal cord and analyzing levels of certain proteins, Science Magazine reports. 

[READ: Gene Therapy for HIV Delivers Hopeful Results]

This new blood test is significant because it has the potential to be more accessible for patients – less expensive than brain scans and less painful than extracting fluid from the spine.

Early discovery of the disease is critical said Federoff in a video interview posted on the Georgetown University Medical Center's website.

"There have been many efforts to develop drugs that were thought to modify the history of Alzheimer’s disease and sadly all of them have failed," he said. One reason that these drugs were ineffective could be that they were tested in patients who were already too sick to be helped, he added.

[ALSO: Low-Protein Diets Reduce Cancer Risk in Adults]

For this study, researchers observed 525 "otherwise healthy" adults who were more than 70-years-old during a 5-year period. By examining blood samples and measuring the amount of 10 specific fats in their blood over time, researchers could discern whether an individual was at risk of “amnestic mild cognitive impairment,” or Alzheimer’s disease, or whether they remained healthy.

By the study’s completion, they discovered 74 adults who showed signs of Alzheimer’s or amnestic mild cognitive impairment (aMCI), believed to be the earliest stage of Alzheimer’s disease. About 46 of the 74 individuals began the study with either Alzheimer’s disease or aMCI and another 28 moved from being healthy without memory impairments to fitting the profile of Alzheimer’s or aMCI. 

In the U.S. 4.5 million people have Alzheimer’s and worldwide about 35 million people suffer from the condition, according to the study. The global figures are expected to double every 20 years reaching 115 million by 2050, according to the World Health Organization.

Researchers at Georgetown University worked alongside six other institutions including the University of Rochester to develop and evaluate the blood test. 

The study was published in Nature Magazine.