DURHAM, N.C. (Ivanhoe Newswire) - More than a million people in the U.S. are living with Parkinson's disease. Some people have it but don't even know it. Did you know small handwriting and loss of smell are early signs of Parkinson's? There is no definitive test to diagnose it, and often, it's only treated after patients start to show the more obvious signs, like tremors or balance issues. But now, researchers have developed a new test that can diagnose Parkinson's disease years before symptoms start.

A tremor that won't stop, slow movements, and rigid muscles are the classic signs of Parkinson's disease that alert doctors that something may be wrong.

"There's really no definitive test in life to know whether someone has Parkinson's disease. And so that really leads to a lot of uncertainty, but it also misdiagnosis unfortunately," said Laurie H. Sanders, PhD, Associate Professor of Neurology at the Duke University School of Medicine.

Because there's been no definitive test -- patients are left wondering for months, sometimes years -- what's wrong? But a team of neuroscientists at Duke University hopes to change that. They've developed a simple blood test that can precisely diagnose Parkinson's disease sometimes before symptoms start.

"We saw increases in our marker potentially decades before that they have the disease," said Sanders.

This test checks for damage inside the mitochondria, which are the cells' energy centers. The test can tell with 85 percent accuracy whether someone has the disease.

"Our marker not only identifies Parkinson's patients, but those that might have some particular underlying biology that might match best with some drugs," explained Sanders.

The next step for the blood test is to move it into larger clinical trials, with thousands of people, worldwide. Researchers hope to make this test available to everyone within the next five years.

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