A simple blood test has been shown to be highly accurate in predicting the onset of Alzheimer’s disease (AD) in otherwise healthy people years before symptom onset.
If these initial findings, published online this week in Nature Medicine, are supported by future research, the blood test could provide a much sought after biomarker for early detection of the disease.
“We posit that this ten–phospholipid biomarker panel, consisting of [phosphatidylcholine] and [acylcarnitine] species, reveals the breakdown of neural cell membranes in those individuals destined to phenoconvert from cognitive intactness to [mild cognitive impairment] or AD and may mark the transition between preclinical states where synaptic dysfunction and early neurodegeneration give rise to subtle cognitive changes,” wrote Howard J. Federoff, MD, PhD, of Georgetown University Medical Center in Washington, D.C., and colleagues.
Current biomarkers being researched as early indicators of AD include measurement of cerebrospinal fluid tau and brain amyloid imaging, though these techniques are limited by invasiveness or cost, and may not have the sensitivity to definitively diagnose the disease.
An easy-to-use blood test would be a boon to physicians hoping to identify those destined to suffer from AD and aid greatly in research for treatments.
Federoff and colleagues enrolled a total of 525 people over age 70 in their study. The authors tested the cognitive and memory skills of the participants, as well as took blood samples, about once every year over the course of the five-year observational study.
The authors analyzed the blood samples of 53 participants with mild cognitive impairment or AD, including 18 who developed symptoms during the study, using mass spectrometry. They compared these results with 53 subjects who remained cognitively healthy.
Federoff and colleagues eventually zeroed in on a set of 10 phospholipids that were consistently detected at lower levels in the blood of those who had developed cognitive impairment. This biomarker profile was validated in a set of 41 additional study participants, and the authors reported that it could distinguish between those who would remain cognitively healthy and those who would demonstrate impairment with 90 percent accuracy.
While the results are encouraging, they will need to be validated in larger studies, and Federoff noted that different age groups and more diverse racial populations will need to be included in these studies.
Heather Snyder, spokeswoman for the Alzheimer’s Association, was quoted by CNN saying, “It’s an intriguing study. But it is very preliminary.”