Georgetown researchers have developed a simple blood test that can predict if a healthy person will develop dementia symptoms within three years.
One of the biggest challenges with Alzheimer’s disease is identifying aging individuals who are cognitively normal right now -- but may be prone to develop dementia. Identifying them before its onset gives preventive therapy a chance.
A team led by Howard Federoff of Georgetown University Medical Center tested the cognitive and memory skills of 525 participants over the age of 70. They also took blood samples every year for five years.
They found 10 fatty molecules, or lipids, circulating at consistently lower levels in the bloodstream of the participants who already have Alzheimer’s and those who went on to develop cognitive impairment.
“We don’t really know the source of the 10 molecules,” Federoff tells Nature News, but he proposes that concentrations of the lipids might somehow reflect the breakdown of the membranes of neural cells.
With their blood profile of lipid metabolites, the researchers then sorted through blood samples from 41 participants to see if they could accurately identify those early degenerative changes in their neurons. Turns out, their panel of lipid biomarkers can determine with 90 percent certainty whether a cognitively healthy person will develop mild cognitive impairment (MCI) or Alzheimer’s in the next two or three years.
There’s currently no cure or effective treatment for Alzheimer’s, which is expected to double every 20 years worldwide: from 35.6 million individuals in 2010 to 115.4 million by 2050, according to the World Health Organization. Efforts to develop drugs to delay or reverse the disease’s progression have all failed -- partly because the drugs were evaluated too late in the disease process.
This discovery makes it possible to develop earlier treatment options. “The preclinical state of the disease offers a window of opportunity for timely disease-modifying intervention,” Federoff says in a press release. A screening test based on the findings could be available in as little as two years.
The work was published online in Nature Medicine this week.