‘Big Step Forward’: New Laboratory Test Could Accelerate Parkinson’s Disease Diagnosis and Research

CNN
—

A laboratory test that could tell a doctor if someone has Parkinson’s disease has long been a goal of researchers.

Doctors now diagnose the progressive condition by looking for obvious physical symptoms such as tremors, cessation of walking, stiffness, or poor balance. About 90,000 Americans are diagnosed each year based on these symptoms, according to the WHO. Recent research.

These signs can be subtle at first and can make it difficult to distinguish Parkinson’s disease from other diseases until the disease is more advanced and affects more of the brain.

The lack of laboratory tests that can detect the disease in its early stages also hinders the search for new treatments. Studying a group of people with the same motor symptoms means erroneously including people whose condition could be caused by something else.

It also means that people are usually studied when the disease is well advanced. Many treatments are given at or before the first signs of symptoms appear. Sometimes it works best.

All that could soon change, thanks to a new test that can detect traces of a key protein called alpha-synuclein that misfolds and gums up certain areas of the brain.

One test, SYNTap, which looks for this misfolded protein species in spinal fluid, has just been probed in the Parkinson’s Disease Progression Markers initiative. great research Conducted by the Michael J. Fox Foundation. Several companies have developed versions of this type of test.

join another test Called Syn-One, it detects trace amounts of proteins in the skin. Syn-One He has been available since 2019 and is being researched with funding from the National Institutes of Health.

If they return a positive result, the new test does not diagnose Parkinson’s disease, but rather points to a range of disorders caused by abnormal aggregation of the α-synuclein protein. It includes dementia and multiple system atrophy, a rare disorder that damages several areas of the brain. Parkinson’s disease is the most common of these diseases.

Parkinson’s disease affects the nervous system and can cause problems such as depression, anxiety, cognitive impairment, sleep disturbances, hallucinations and loss of smell, in addition to movement-related symptoms. can lead to serious complications. Little is known about the exact cause.

Dr. Kathleen Poston, a professor of neurology and neuroscience at Stanford University, said the test “is like a new chapter for those of us with Parkinson’s who can really focus on biology.” I’m here. SYNTap test.

“I think this will make our efforts and clinical trials very fast,” Poston said. increase.

Physicians have access to this test, but it has not been shown to be reliable in large clinical trials.

and study The SYNTap test, published Wednesday in The Lancet Neurology, was given to 1,100 participants, including people with Parkinson’s disease, people with undiagnosed genetic or clinical risk factors, and healthy controls. Overall, the test correctly identified people with Parkinson’s disease 88% of the time and correctly excluded them 96% of the time.

“This method shows that Parkinson’s disease can be detected fairly accurately in asymptomatic patients,” said Dr. Andrew Ko, a neurosurgeon at the University of Washington School of Medicine, who was not involved in the study. . “This is a big step forward in showing that this type of test is accurate.”

The test was most accurate in people with no known genetic risk for Parkinson’s disease, who also lost their sense of smell.In this group, the test correctly detected the disease 99% of the time. If the sense of smell was not lost, the accuracy he dropped to 78%.

In people with mutations in the LRRK2 gene, the most common genetic risk, the test correctly flagged Parkinson’s disease only about 67% of the time.

This means that while the test is very good at ruling out Parkinson’s disease, it can miss people who actually have Parkinson’s disease.

“Just because you’ve had this test and it’s ‘normal’ or negative doesn’t mean you don’t have Parkinson’s disease,” says Kelly, a neurologist and director of the Movement Disorders Division at Johns Hopkins University. Dr. Mills said I wasn’t involved in the research.

For the time being, that means the test itself is not very helpful for individual patients.

“This is a big problem for research, and I think it’s going to be a big problem for patients,” said Mills.

The study authors agree.

“Currently, this test is not very useful in routine clinical care,” said study author Dr. Andrew Sideloof, a neurologist at the University of Pennsylvania Perlman School of Medicine.

Treatment for Parkinson’s disease is based on symptom relief, and all the tests can do is help doctors narrow the diagnosis. There may be

It’s also a highly invasive test that requires a painful procedure called a spinal tap, but researchers can transfer its results into other types of biological samples that are more easily collected, such as blood or saliva. I would like to convert immediately.

One of the most promising results of this study was those with early changes known to be strongly associated with the development of Parkinson’s disease. His alpha-synuclein was detected in 16 of his 18 who lost his sense of smell. Another of his group of 33 people with REM sleep behavior disorder kicked, punched, and punched in their sleep to make their dreams come true. The test detected alpha-synuclein in 28.

The group was so small, the researchers say, that these tests need to be repeated to see if they can detect the disease before it impairs exercise.

But that’s the goal, according to Michael J. Fox Foundation research funders, and they believe this test will revolutionize research.

Foundation CEO Deborah Brooks said: “We will continue at a rapid and aggressive pace,” she said.

When Brooks learned of the SYNTap test results, he went to see actor and philanthropist Fox, who was on vacation with his family, and told him privately. Fox has had Parkinson’s disease since 1991. .

Together, they called one of the Foundation scientists, Dr. Todd Scherrer. Dr. Todd Scherrer is a Neuroscientist who is also Chief of the Foundation and his Mission Officer.

“So Todd will call me and he’ll give me all the details. Just headlines. We had a breakthrough,” Brooks said.

Fox and Sherer have been looking for biomarkers for this condition for over a decade.

When Scherrer finished his presentation, Fox leaned over, picked up his laptop, and kissed him on the head.

“This is great,” he said.