Alzheimer's Blood Test Could Detect The Disease Before Symptoms Set In

A new blood test being developed by British scientists could detect Alzheimer’s disease long before it starts, allowing patients to start treatment earlier than ever before.

Researchers from the University of Nottingham say their test looks for a combination of markers in the blood that wave red flags for the neurodegenerative illness. These warning signs include amyloids, the misfolded proteins that can accumulate in plaques in the brain; apolipoprotein E, or ApoE, a variant of which is linked to Alzheimer’s; and other proteins linked to inflammation.

"Our findings are exciting because they show that it is technically possible to distinguish between healthy people and those with Alzheimer's using a blood test,” University of Nottingham professor Kevin Morgan told the BBC. "As blood tests are a fast and easy way of aiding diagnosis, we are really encouraged by these findings and the potential they hold for the future."

But don’t hold your breath: It could be 10 years or more before the test is available to patients. The BBC story doesn't elaborate on the reasons behind the delay, but it's likely due to the fact that the test needs to be evaluated in a population over a period of time, so researchers can follow up with them to make sure the test doesn't give false positives or false negatives.

When the test does become available, it could be used to screen people for the disease long before symptoms appear.

“The way we see it working is you can test people and it will tell them if they have the all-clear, or if they are medium- or high-risk,” Morgan told the BBC. "If they are medium-risk, they can be monitored closely and high-risk patients can be referred to a specialist for more in-depth testing."

Meanwhile, a cure for Alzheimer’s is still a long way off.

“We've had a lot of failures in Alzheimer's drugs. But you learn from them,” Guy Eakin, vice president of scientific affairs at the American Health Assistance Foundation, said last May.

In May 2012, federal officials announced the start of the first clinical trial of a drug aimed at actually preventing – not just treating or curing -- Alzheimer’s disease.

The trial – a $100 million collaboration among the U.S. National Institutes of Health, the Arizona-based Banner Alzheimer's Institute, drug giant Genentech and the University of Antioquia in Colombia -- approaches the disease from an unusual angle. Instead of testing drugs on patients with full-blown dementia, the trial focuses on around 300 people in the U.S. and Colombia who carry a genetic mutation that usually triggers Alzheimer's symptoms around age 45. Most of the study subjects are from a single large extended family.

Prevention efforts for Alzheimer’s focus on a mutation that affects the gene PSEN1, which is involved in the production of amyloid protein. Clumps of beta amyloid proteins, known as plaques, and smaller aggregations of amyloid known as ligomers are thought to play a key role in Alzheimer's disease when they build up in the brain.

Crenezumab, the drug being tested, is an antibody that binds to beta amyloid and helps clear out those excessive deposits.