New Criteria for Diagnosing Alzheimer's Coming
Earlier Diagnosis Needed as New Drugs Come Down the Pike
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Early Alzheimer's Screening Tests on the Horizon
In the past, Alzheimer's disease was only accurately diagnosed after death, when doctors performed an autopsy to examine changes in brain tissue.
But that was then. Now, there are new imaging biomarkers being developed that can help doctors identify risk of Alzheimer's disease earlier.
Changes in the brain triggered by Alzheimer's disease develop slowly over many years, which is why it's important to catch the disease earlier, says Guy McKhann, MD, professor at the Mind/Brain Institute at Johns Hopkins University in Baltimore.
"The disease itself starts many years before the dementia appears," he says. That said, "these tests are not ready for prime time except under very controlled circumstances."
Marilyn Albert, PhD, a professor of neurology at Johns Hopkins University in Baltimore, agrees. "We don’t think they are ready to be used by clinicians in the community yet," she says. "These biomarkers and their cut-offs need to be standardized across the board before they can be used outside of research settings."
Biomarker Tests Not Ready for Prime Time, Yet
"We need to standardize biomarkers and diagnostic criteria so ... it means the same thing across all centers," says Reisa A. Sperling, MD, an associate professor of neurology at Brigham and Women's Hospital in Boston.
Phelps adds that using these tests before they are validated could do more harm than good.
"In some studies conducted by the best labs in the world, there was a 30% discrepancy among results, and until they validate a better way to do some of the measurements, there may be too many false-positives and we would be telling people they were in trouble when they weren't," he says.
That's not to say you must sit idly by while researchers scurry to complete their task, Sperling says.
"Do everything possible to keep socially, physically and mentally active and lead a healthy lifestyle," she says.
"If you are seeing any kind of symptoms in yourself or your family like getting confused or forgetting things or short-term memory loss that is happening more regularly and getting worse, seek out advice form a specialist or memory disorders clinic," Phelps says. These subtle cognitive changes may appear a decade before the onset of dementia.