How a new blood test to detect Alzheimer’s disease can stop memory loss earlier

The prognosis for Alzheimer’s disease is much better when patients are diagnosed as early as possible. And there’s great news on that front.

WTOP talked to a doctor about an advancement in testing that he says will help patients get treatment faster.

“This is really big news,” said Dr. Scott Turner, professor of neurology and director of the memory disorders program at Georgetown University.

On Friday, the Food and Drug Administration approved the first blood test to diagnose Alzheimer’s disease.

There are currently about 5 million people with Alzheimer’s disease in the U.S., according to Turner. It is the most common cause of dementia in the United States.

He said the new blood test will help doctors identify and treat patients more quickly.

“We now have treatments that are most effective in early stages of Alzheimer’s disease, and we would like to identify people who are possible candidates for this,” Turner said.

Prior to this new approval, Turner said diagnosing could be difficult.

“Before this FDA approval, we relied primarily on PET scans of the brain, which are quite expensive, or spinal taps, which require collection of fluid from the lumbar space, which are more invasive,” he said. “So this is definitely a big advance.”

The FDA said in its announcement that 10% of people aged 65 and older have Alzheimer’s — and that by 2050 that number is expected to double.

“This is clearly a breakthrough in the field,” Turner said. “We now have treatments that are targeting the amyloid that accumulates in the brain, and this is one of the proteins that’s measured by this new blood test.”

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