Significant number of Parkinson’s cases can be attributed to preventable risk factors, researcher says

New research published by neurology researchers at the University of Alabama at Birmingham in npj Parkinson’s disease found that preventable risk factors play an important role in a person’s risk of developing Parkinson’s disease.

The 1,223 people studied at UAB from the southern region of the United States included 808 with PD and 415 neurologically healthy controls. The researchers came away with two significant findings indicating that preventable risks affect the risk of Parkinson’s disease: repeated hits to the head sustained during activities like football and exposure to herbicides and pesticides.

First, the study found that repeated blows to the head during sports or military combat, which seem harmless and may not even cause a concussion, doubled the risk of developing PD later in life. Second, 23% of PD cases in both men and women were associated with exposure to pesticides, herbicides, or military-related chemical exposures. Together, head injuries and exposure to environmental toxins may account for nearly one in three cases of PD in men and one in four cases in women.

“Parkinson’s disease is increasing rapidly globally, and there is an unspoken assumption that there is no prevention, but there is,” said Haydeh Payami, Ph.D., professor and chair of the John T. & Juanelle D. Strain Chair in the UAB Department. of neurology, professor at the Center for Neurodegeneration and Experimental Therapeutics and lead author of the study.

“Our research has demonstrated that a substantial fraction of Parkinson’s disease in the Deep South is attributable to risk factors that can be reduced or avoided. Our paper indicates how many cases of Parkinson’s disease could potentially be prevented if products toxic chemicals were eliminated and if we made contact sports like football are safer.”

While genes play an important role in a person’s exposure to PD cases, with approximately 5% of cases caused by inherited genetic mutations, the remaining 95% of PD cases are believed to be caused by various external factors that cause disease in individuals who are genetically susceptible to their harmful effects.

As the research for this study was conducted at UAB and the research participants were all from the Deep South, Payami shared that the results indicate that the incidence of the disease will likely vary by population depending on the prevalence of risk factors.

For example, in Europe, where many toxic chemicals commonly found in U.S. products are banned, a smaller fraction of Parkinson’s disease could be attributed to these specific chemicals. Additionally, the numbers could change over time, for better or worse, depending on steps taken now to clean up the environment and improve health and safety standards.