A new study from a database of millions of veterans nationwide reveals a possible connection between hearing loss and Parkinson’s disease.

The study, published in the journal JAMA Neurology, further suggests that veterans who are fitted with a hearing aid within two years of hearing loss appear to lower the risk of developing Parkinson’s. The study was a collaboration between researchers at Oregon Health & Science University and the VA Portland Health Care System.

“We still have much to learn about how hearing loss contributes to Parkinson’s and how hearing aids might work to lower one’s risk,” said lead author Lee Neilson, M.D., assistant professor of neurology in the OHSU School of Medicine and a staff neurologist for the VA Portland. “Considering there are few downsides to getting screened and fitted for a hearing aid, we would encourage everyone to do it.”

The study examined 23 years’ worth of records from nearly 7.3 million United States military veterans who had an audiogram between Jan. 1, 1999, and Dec. 30, 2022.

Results showed that those with hearing loss have a much higher risk of developing Parkinson’s later in life. Additionally, the study found that those who have the most significant hearing loss seemed to have the highest risk of developing Parkinson’s.

In addition to Neilson, co-authors include Kelly M. Reavis, Ph.D., with the VA’s National Center for Rehabilitative Auditory Research and the OHSU-Portland State University School of Public Health, Jack Wiedrick, M.S., M.A., with the Biostatistics, Epidemiology and Research Design Program at OHSU, and Gregory D. Scott, M.D., Ph.D., professor of pathology in the OHSU School of Medicine and physician of pathology at the VA Portland.

The research was supported by Veterans Affairs Biomedical Laboratory Research and Development grant awards CDA2 IK2 BX00f760-01A1 and CDA2 IK2 CX00253-01A1; the John and Tami Marick Family Foundation, Collins Medical Trust Award, OHSU Medical Research Foundation New Investigator Award and PCO Pilot Award; the National Center for Rehabilitative Auditory Research grant award C2361C/I50 RX002361 and the Parkinson’s Disease Research, Education, Clinical Center at the VA Portland.

Article originally appeared on OHSU News