Parkinson’s Risk & Prevention: What We Know So Far

Parkinson’s disease is increasingly recognized as a condition that begins long before movement symptoms appear. Subtle physiological changes, sleep disturbances, and sensory alterations can emerge years, even decades, before diagnosis. Understanding these early signals not only helps identify individuals at risk, but also supports efforts to prevent or delay the onset of Parkinson’s altogether.

Dr. Jonathan Isaacson explains that “we know that there's some prodromal risk factors that are associated with Parkinson's disease.”

Early Warning Signs: What Happens Before Motor Symptoms

One of the strongest predictors is REM sleep behavior disorder (RBD), in which individuals physically act out their dreams by kicking, yelling, or thrashing during sleep. Though it may be first noticed by a bed partner, confirmation requires a sleep study. When RBD is verified on polysomnography, Dr. Isaacson notes that
“patients who have a positive test have over a 90% chance of developing Parkinson's disease in the next 5–10 years, what we see in the studies.”

Other early symptoms include anosmia (loss of sense of smell) and chronic constipation, which can appear decades before a symptom onset of Parkinson's disease develops. Together, these signs offer a window into Parkinson’s long prodromal phase, prompting ongoing efforts to develop better diagnostic tools.

Genetic and Environmental Influences on Parkinson’s Risk

Risk for Parkinson’s arises from a combination of genetic vulnerability and environmental exposures. Dr. Isaacson notes that “we think there's epigenetic risk involved… and we've been able to identify multiple different genes involved.”

Some genetic variants, such as PRKN, are linked with early-onset disease. Others such as LRRK, LRRK2, and GBA, appear more often in specific populations, such as the Ashkenazi Jewish population. These genes do not guarantee disease but do increase susceptibility.

Environmental risk is more difficult to study. As Dr. Isaacson explains, “with any environmental factor, it's very difficult to prove causality.” Still, research has associated Parkinson’s with exposures such as fertilizers, golf course chemicals, and various environmental pollutants. He notes that “Parkinson's has increased in prevalence in all age ranges,” raising concern about environmental contributors to its rising incidence.

Lifestyle Factors That May Reduce Risk or Slow Progression

Evidence increasingly supports the role of lifestyle in modifying Parkinson’s risk and progression. One of the most consistently beneficial behaviors is cardiovascular exercise. Dr. Isaacson emphasizes that “things that we know slows the progression of Parkinson's disease, are things like cardiovascular exercise.”

A commonly recommended target is 150 minutes per week, which may also help those in prodromal or at-risk stages.

Diet emerges as another meaningful factor. A Mediterranean-style pattern, “healthy fishes, nuts, fruits and vegetables, avocado, healthy fats,” has been associated with delayed onset and slower progression of Parkinson’s disease.

Vascular health may also play a role. Dr. Isaacson notes that “similar to Alzheimer's, different vascular risk factors can kind of speed up the progression of some of these conditions,” and improving them may “slow down the progression of both Alzheimer's and Parkinson's Disease.”

Looking Ahead

As research uncovers more about the prodromal phase, genetic influences, environmental contributors, and modifiable lifestyle factors, the possibilities for prevention and early intervention continue to expand. Rather than waiting for motor symptoms to appear, clinicians may soon be able to identify risk earlier, personalize care, and slow disease progression before significant neurological change occurs.

This evolving understanding represents a hopeful shift in the field—one where risk does not have to become destiny, and where early action may make a meaningful difference in long-term outcomes.

For more insights on Parkinson's risk factors and prevention strategies, watch our full conversation with Dr. Jonathan Isaacson in the video above.

By Alicia Barber Minteer, PhD