brainscanA blood test that can predict with 90% accuracy whether someone will go on to develop Alzheimer’s disease in the next 3 years has been developed by scientists in the US.

Researchers, led by scientists from Georgetown University in Washington DC, have discovered 10 lipid biomarkers in the blood that predict Alzheimer’s or mild cognitive impairment (MCI).

The discovery, published in the journal Nature Medicine, could lead to people receiving earlier treatment for Alzheimer’s, when therapy could be more effective at slowing or even preventing onset of the disease.

Researchers followed a group of over-70s for 5 years. Each participant gave blood samples and took part in memory tests once a year. The researchers analysed blood samples from 147 people: 73 who experienced no significant memory decline during the study, 28 who went on to develop either Alzheimer’s or MCI and 46 who were found to have either Alzheimer’s or MCI at the start of the study.

The results showed there were differences in the metabolites found in the blood of those with Alzheimer’s or MCI compared to those without memory problems.

“Our novel blood test offers the potential to identify people at risk for progressive cognitive decline and can change how patients, their families and treating physicians plan for and manage the disorder,” said D. Howard J. Federoff, executive vice president of health sciences at Georgetown University Medical Center, and one of the study’s authors.

“The preclinical state of the disease offers a window of opportunity for timely disease-modifying intervention, and biomarkers defining this asymptomatic period are critical for successful development and application of these therapeutics.

“The lipid panel was able to distinguish with 90% accuracy these two distinct groups – cognitively normal participants who would progress to MCI or [Alzheimer’s] within two to three years, and those who would remain normal in the near future.

“We consider our results a major step toward the commercialization of a preclinical disease biomarker test that could be useful for large-scale screening to identify at-risk individuals,” Federoff concludes. “We’re intending to design a clinical trial where we’ll use this panel to identify people at high risk for Alzheimer’s to test a therapeutic agent that might delay or prevent the emergence of the disease.”

Step forward

Dr Simon Ridley, head of research at Alzheimer’s Research UK, welcomed the research: “Alzheimer’s disease begins to develop long before symptoms such as memory loss appear, but detecting the disease at this pre-symptomatic stage has so far proved difficult,” he said. 

“More work is needed to confirm these findings, but a blood test to identify people at risk of Alzheimer’s would be a real step forward for research. To test the effectiveness of potential new drugs, it’s important to be able to recruit people to clinical trials in the early stages of the disease, when such treatments are most likely to be effective. If confirmed, these results could also aid efforts to develop better tools for diagnosing Alzheimer’s – allowing people with the disease to access crucial support and existing treatments sooner. We now need to see further studies to investigate the accuracy of this test in larger groups of people.”

Further reading: Cameron reveals dementia research funding boost.