Testing saliva glands may be a new way to diagnose Parkinson's disease, according to research from Mayo Clinic in Arizona and Banner Sun Health Research Institute.
"We have previously shown in autopsies of Parkinson's patients that the abnormal proteins associated with Parkinson's are consistently found in the submandibular saliva glands, found under the lower jaw,” says study author Charles Adler, M.D., Ph.D., a neurologist with Mayo Clinic in Arizona. “This is the first study demonstrating the value of testing a portion of the saliva gland to diagnose a living person with Parkinson's disease. Making a diagnosis in living patients is a big step forward in our effort to understand and better treat patients, as there is currently no diagnostic test for Parkinson's disease."
The study included 15 people with an average age of 68 who had Parkinson's disease for an average of 12 years, responded to Parkinson's medication, and did not have known saliva gland disorders. Biopsies were taken of two different saliva glands: the submandibular gland and the minor saliva glands in the lower lip. The abnormal Parkinson's protein was detected in 9 of the 11 patients who had enough tissue to study. While still being analyzed, the rate of positive findings in the biopsies of the lower lip glands appears much lower than for the lower jaw gland.
"This procedure will provide a much more accurate diagnosis of Parkinson's disease than what is now available," says study co-author Thomas Beach, M.D., with Banner Sun Health Research Institute. "One of the greatest potential impacts of this finding is on clinical trials, as at the present time some patients entered into Parkinson's clinical trials do not necessarily have Parkinson's disease, and this is a big impediment to testing new therapies."
"This finding may be of great use when needing definitive proof of Parkinson's disease, especially when considering performing invasive procedures such as deep brain stimulation surgery or gene therapy," adds Dr. Adler.
The study was released today and will be presented at the American Academy of Neurology's annual meeting in San Diego in March. The work was funded by the Michael J. Fox Foundation for Parkinson's Research.