Does Untreated Snoring Cause Parkinson’s? What New Research Reveals About Untreated Sleep Apnea Parkinson’s Risk

A landmark study published in JAMA Neurology in November 2025 has revealed a disturbing connection between untreated sleep apnea and Parkinson’s disease risk. Researchers analyzed more than 11 million veterans’ health records and found that people with untreated obstructive sleep apnea were roughly twice as likely to develop Parkinson’s disease compared to those without sleep-disordered breathing. The finding is significant for anyone who snores heavily or has been told they stop breathing during sleep — and it carries an urgent message about the importance of early treatment.

But the study also contained a critically important piece of good news. Patients whose sleep apnea was treated did not show elevated Parkinson’s risk. That single finding transforms this from a story about fear into one about action: what you do about your snoring Parkinson’s disease risk may genuinely matter for your long-term brain health.

The Study: Untreated Sleep Apnea Parkinson’s Link in 11 Million Records

The research, conducted by a team at Oregon Health & Science University (OHSU), represents one of the largest epidemiological analyses ever performed on the relationship between sleep apnea and neurodegenerative disease. Using the Veterans Health Administration database — which contains longitudinal medical records spanning decades — the investigators followed patients with diagnosed obstructive sleep apnea and compared their rates of Parkinson’s disease to matched controls without OSA.

The numbers were striking. After adjusting for age, sex, body mass index, smoking status, cardiovascular disease, diabetes, and other confounders, the data showed that untreated OSA approximately doubled the risk of a subsequent Parkinson’s diagnosis. The association held across age groups and was not explained by shared risk factors or diagnostic overlap.

What made this study particularly compelling was the treatment comparison. Patients who received and adhered to treatment for their sleep apnea — whether through CPAP, oral appliance therapy, or other interventions — did not show the same elevated risk. Their Parkinson’s rates were statistically indistinguishable from those of people who never had sleep apnea at all. This treatment-response pattern strengthens the case that the relationship is causal rather than merely correlational.

How Snoring and Sleep Apnea Damage Dopamine-Producing Brain Cells

Parkinson’s disease is caused by the progressive loss of dopaminergic neurons in a brain region called the substantia nigra. These neurons produce dopamine, the neurotransmitter essential for smooth, coordinated movement. As these cells die, patients develop the characteristic symptoms of Parkinson’s: tremor, rigidity, slowness of movement, and balance problems.

The proposed mechanism linking sleep apnea to this neurodegeneration centers on intermittent hypoxia — the repeated drops in blood oxygen that occur every time the airway collapses during sleep. In a person with moderate sleep apnea, this can happen 15 to 30 times per hour. In severe cases, it happens more than 30 times per hour, sometimes with oxygen levels plummeting to dangerous lows.

Each hypoxic episode triggers a cascade of damaging biological events. Oxygen deprivation generates reactive oxygen species (free radicals) that cause oxidative stress in neural tissue. It activates inflammatory pathways that produce neuroinflammation. It disrupts the blood-brain barrier, allowing toxins to reach vulnerable neurons. And it impairs the brain’s glymphatic system — the waste-clearance mechanism that operates primarily during deep sleep — which normally removes toxic protein aggregates including alpha-synuclein, the misfolded protein that accumulates in Parkinson’s disease.

If you have read about the connection between snoring and brain damage, this mechanism will sound familiar. The same intermittent hypoxia that shrinks gray matter and damages white matter integrity also appears to selectively target the dopaminergic neurons of the substantia nigra, which are known to be especially vulnerable to oxidative stress.

Why This Matters Beyond Parkinson’s

This study adds to a growing body of research linking untreated snoring and sleep apnea to neurodegenerative disease. Previous studies have already established connections between OSA and cognitive decline, memory loss, and an increased risk of dementia, including Alzheimer’s disease. The Parkinson’s finding extends the evidence to a different category of neurodegeneration entirely.

According to the Parkinson’s Foundation, nearly one million Americans currently live with Parkinson’s disease, with approximately 90,000 new diagnoses each year. The disease has no cure and limited treatment options. Identifying modifiable risk factors — things people can actually change — is therefore a critical public health priority.

What makes sleep apnea especially important as a modifiable risk factor is that effective treatments already exist. Unlike genetic predispositions or environmental exposures that are difficult to control, airway obstruction during sleep can be addressed with devices, lifestyle changes, and medical interventions that are widely available today. And with global sleep apnea prevalence projected to rise sharply by 2050, the urgency of early intervention is only increasing.

Who Should Be Concerned About Snoring Parkinson’s Disease Risk

Not every person who snores occasionally needs to worry about Parkinson’s disease. The risk identified in the JAMA Neurology study applies specifically to obstructive sleep apnea — a condition characterized by repeated partial or complete airway collapse during sleep. However, the line between heavy snoring and sleep apnea is often blurry, and many people with OSA are undiagnosed.

You should pay particular attention if you experience any of the following:

• Chronic loud snoring that occurs most nights and can be heard from another room
• Witnessed apneas — a bed partner has observed you stop breathing, gasp, or choke during sleep
• Excessive daytime sleepiness despite getting what seems like enough sleep
• Morning headaches that resolve within an hour of waking
• Family history of Parkinson’s disease, which may increase your vulnerability to additional risk factors
• Family history of sleep apnea, as the condition has a significant genetic component

The distinction between simple snoring and sleep apnea matters because it is the oxygen deprivation — not the noise itself — that damages the brain. Understanding whether your snoring involves actual breathing interruptions is essential for assessing your personal risk. Our guide on sleep apnea versus snoring explains the differences in detail and can help you evaluate where you fall on the spectrum.

What You Can Do Right Now

The most important takeaway from this research is that treatment appears to be protective. That means taking action now — rather than waiting for symptoms of neurodegeneration — is the rational response. Here is what sleep medicine experts recommend.

Get Evaluated

If you snore heavily or have any of the warning signs listed above, talk to your doctor about a sleep evaluation. Home sleep apnea tests have become more accessible and affordable, and they can determine whether your snoring involves clinically significant oxygen drops. A diagnosis gives you a clear picture of severity and guides treatment decisions.

Start Treating Your Airway Obstruction

For mild-to-moderate obstructive sleep apnea — which represents the majority of cases — a mandibular advancement device (MAD) is a first-line treatment option recommended by the American Academy of Sleep Medicine. These devices work by gently advancing the lower jaw forward during sleep, which pulls the tongue base away from the back of the throat and opens the airway. The result is reduced obstruction, improved oxygen flow, and less snoring.

Unlike CPAP machines, which many patients find uncomfortable and ultimately abandon, oral appliances are discreet, portable, and easy to use consistently. Adherence matters enormously here — the JAMA Neurology study showed that it was specifically treated patients who were protected. A device that sits in your nightstand drawer because it is too cumbersome to use provides no benefit.

Address Contributing Factors

Several lifestyle factors can worsen snoring and sleep apnea. Excess body weight increases fat deposits around the airway. Alcohol consumed within three hours of bedtime relaxes airway muscles and increases collapse. Sleeping on your back allows gravity to pull the tongue into the airway. Addressing these factors alongside a mouthpiece can produce compounding improvements in airway patency and oxygen saturation during sleep. For a broader look at evidence-based sleep optimization strategies and what actually works, our sleepmaxxing guide breaks down the hierarchy of interventions.

Monitor Your Brain Health

If you have a family history of Parkinson’s disease or other neurodegenerative conditions, treating snoring and sleep apnea becomes even more urgent. Discuss your complete risk profile with your physician, and consider baseline cognitive assessments that can track changes over time. Early detection of cognitive shifts, combined with aggressive management of modifiable risk factors like sleep apnea, represents the best available strategy for brain protection.

The Broader Picture: Snoring as a Brain Health Issue

For too long, snoring has been treated as a nuisance — something that disrupts a partner’s sleep but poses no real danger to the snorer. The accumulating evidence tells a very different story. Chronic, untreated snoring and sleep apnea are associated with a range of serious health risks that extend far beyond the bedroom: hypertension, atrial fibrillation, stroke, type 2 diabetes, depression, and now a doubled risk of Parkinson’s disease.

The brain, more than any other organ, depends on a continuous and adequate supply of oxygen. It represents only about 2% of body weight but consumes roughly 20% of the body’s oxygen. When that supply is interrupted dozens or hundreds of times every night for years or decades, the cumulative damage is substantial. The neurons that produce dopamine in the substantia nigra are among the most metabolically active cells in the brain, which may explain their particular vulnerability to the repeated oxygen deprivation caused by sleep apnea.

What the JAMA Neurology study makes clear is that this damage is not inevitable. Treatment interrupts the cycle of hypoxia, reduces oxidative stress, allows the glymphatic system to function properly, and appears to protect the very neurons that Parkinson’s disease destroys. The earlier treatment begins, the less cumulative damage the brain sustains.

When to See a Doctor

You should seek medical evaluation for your snoring if any of the following apply:

• Your snoring is loud enough to disturb others or wake you from sleep
• You have been told you stop breathing or gasp during sleep
• You experience unexplained daytime fatigue or difficulty concentrating
• You have a family history of Parkinson’s, Alzheimer’s, or other neurodegenerative disease
• You have additional risk factors for sleep apnea including obesity, a large neck circumference, or hypertension

A sleep specialist can order a diagnostic sleep study, determine the severity of any airway obstruction, and recommend the most appropriate treatment. For many patients with mild-to-moderate sleep apnea, an oral appliance like a mandibular advancement mouthpiece is the recommended starting point — effective, comfortable, and far more likely to be used consistently than a CPAP machine.

The Bottom Line

The connection between untreated sleep apnea and Parkinson’s disease represents one of the most significant findings in sleep medicine in recent years. A study of more than 11 million health records found that untreated OSA roughly doubles Parkinson’s risk — but that patients who received treatment were protected. The mechanism is biologically plausible: repeated oxygen deprivation damages the dopamine-producing neurons that Parkinson’s disease destroys.

If you snore heavily, the responsible course of action is not to ignore it and hope for the best. It is to get evaluated, start treatment, and protect your brain while you still can. For mild-to-moderate cases, a well-designed mouthpiece that advances the jaw and opens the airway can be the difference between nightly oxygen deprivation and restorative, brain-protecting sleep.