A simple blood test could lead to early diagnosis of Parkinson's disease -- before tell-tale symptoms like tremors develop, according to new research led by a professor at the University of Medicine and Dentistry of New Jersey.
Parkinson’s is generally diagnosed after the disease is already more advanced. By the time rigid muscles, tremors and loss of balance point to Parkinson’s, nerve cells in the area of the brain that controls motor activity are already damaged.
Getting the Parkinson’s diagnosis earlier, before symptoms appear, would help patients manage their illness better -- and help scientists figure out how to halt or reverse the disease.
A research team led by Dr. Robert Nagele, a professor at the UMDN-School of Osteopathic Medicine in Stratford, may have achieved a key breakthrough.
In a paper published in the online, open-access scientific journal PLoS One, Nagele reports on the success of a blood test that diagnoses the disease by identifying autoantibodies that are specific to the body’s response to the brain damage caused by Parkinson’s.
Nagele said his theory is that since brain cell death occurs in Parkinson’s before the symptoms appear, the autoantibodies which his test detects should also start showing up in the blood before symptoms are present. “We should be able to detect Parkinson’s even before your hands begin to shake,” Nagele said.
His hope is eventually “when you go to the doctor once a year for your annual checkup and get your blood sugar and cholesterol tested, you will also get a test for neurodegenerative diseases” such as Parkinson’s.
But there remain several hurdles to cross on the path to a commercial blood test for Parkinson’s. Nagele’s initial study of 199 individuals, some with and some without Parkinson’s, worked “97.1 percent of the time, which is very, very high in terms of accuracy,” he said. A verification study is underway, and if it succeeds, Nagele will work with the Food and Drug Administration to design a larger study, on perhaps 1,000 people, in order to obtain FDA approval for commercial production.
Nagele has founded Durin Technologies, which has licensed the patent from the university and seeks to develop the discovery into a diagnostic product.
If Nagele can develop an early blood screen for Parkinson’s, it will be a major medical breakthrough, according to Dr. James C. Beck, director of research program for the Parkinson’s Disease Foundation. Currently, the diagnosis is performed through clinical examination of the patient’s symptoms.
“The process of getting the diagnosis can be quite time-consuming -- it can take six months to a year before a clinician feel comfortable” making the diagnosis, Beck said. Other neurological disorders mimic Parkinson’s, which is misdiagnosed about 15 percent of the time.
Maple Shade-based neurologist Dr. Manzoor Abidi, who has treated thousands of Parkinson’s patients, said diagnosis begins “by observing the patients literally as they walk into your office. About 90 percent of the time, that is when you start to suspect” that the trouble is Parkinson’s.
The most common symptom is the tremor, followed by a variety of other motor function impairments, including rigidity, inability to achieve a normal gait while walking, and problems with handwriting. In the past several years, research has found that more than 85 percent of those with Parkinson’s also have an impaired sense of smell, Abidi said.
There is no drug to halt or reverse Parkinson’s, which Beck said afflicts more than 1 million nationwide, and an estimated 19,000 in New Jersey. Most patients take levodopa, which treats the symptoms by enabling the brain to release dopamine, but levodopa is less effective as the disease worsens.
A blood test for Parkinson’s that identifies the disease years before symptoms appear would accelerate research by identifying patients who can be recruited for clinical trials of the new drugs scientists are now trying to discover, he said.
“Early diagnosis with a blood test is the holy grail,” Beck said. “Anytime we can move the diagnosis earlier in the disease process bodes well for the time when we have therapies that can actually modify the disease.”