LUND, Sweden, Sept. 22 (UPI) -- Using a substance that binds to proteins in the brain called amyloids, and positron emission tomography, or PET, scans, researchers have found the method can detect early markers for Alzheimer's disease as accurately as cerebrospinal fluid sample testing.
The most common methods for diagnosing Alzheimer's are cognitive memory tests and computed tomography, or CT, scans. While those tests are reasonably accurate, researchers found that using either the amyloid PET test or fluid sample made them significantly more accurate.
The potential to diagnose patients earlier is seen as having as much benefit for current patients as it could for the development of pharmaceuticals to treat the disease.
"Previous drug trials to evaluate new treatments for the presence of amyloid in Alzheimer's cases failed, partly because treatment began too late in the course of the disease," said Oskar Hansson, an associate professor and neurologist at Lund University, in a press release. "With two accurate tools for early diagnosis, we can identify suitable participants at an early stage of Alzheimer's disease. This will considerably increase the chances of being able to prove a positive effect for new drugs."
Researchers first reviewed the Swedish BioFINDER Study, which worked with 122 healthy elderly patients and 34 who had mild cognitive impairment who developed Alzheimer's disease within 3 years. That study found no great difference in diagnosis between the PET and fluid analysis tests.
The researchers then replicated the previous study with 146 healthy elderly patients and 64 patients with mild cognitive impairment or Alzheimer's disease. All of the patients were given a substance which binds to the protein β-amyloid in the brain. Researchers then mapped the patients' brains using PET scans to indicate the presence of amyloids.
There was no major difference between the results using either testing method as researchers said they helped to correctly identify Alzheimer's disease development during patient's next decade of life. The two tests were shown to be about 90 percent accurate, and researchers said that when one of the tests was not done, diagnosis was only about 60 to 70 percent.
"Our conclusion is therefore that the two methods work equally well to achieve this aim," said Dr. Sebastian Palmquist, a researcher at Lund University. "One can thus choose the method on the basis of cost, expertise or patient preference."
The study is published in Neurology.