The hidden connection between snoring, interrupted sleep and rising global Parkinson’s epidemic

Untreated sleep apnea has now been linked to an increased risk of developing Parkinson’s disease, according to a major new study.

Researchers examined a large cohort, some of whom had been diagnosed with obstructive sleep apnea, a condition in which breathing repeatedly stops and starts during sleep.

The participants were followed for nearly five years to determine who developed Parkinson’s disease. The findings, published in JAMA Neurology, reveal a significant association between the two conditions.

Sleep apnea is a disorder characterised by repeated pauses in breathing during sleep, which lead to drops in oxygen levels and disrupted rest. It can cause symptoms such as loud snoring, daytime fatigue, headaches, and long-term health complications.

Parkinson’s disease is a progressive neurological disorder caused by the breakdown of dopamine-producing nerve cells in the brain. It results in symptoms such as tremors, muscle stiffness, and slowed movement.

Electronic health records

Researchers analysed electronic health records of over 11 million US veterans between 1999 and 2022, excluding anyone who already had Parkinson’s at the start. Participants were followed for an average of nearly five years to assess whether those diagnosed with obstructive sleep apnea were more likely to develop Parkinson’s disease.

The study found that individuals with sleep apnea had a higher incidence of Parkinson’s compared with those without the condition, even after adjusting for age, body mass index, other health conditions, smoking, and comorbidities.

Specifically, there were an estimated 1.61 additional cases of Parkinson’s per 1,000 people over six years among those with sleep apnea. The increased risk was particularly notable among female veterans, although it was observed across the entire cohort.

The researchers also examined the effect of treating sleep apnea with continuous positive airway pressure (CPAP) therapy. They found that early treatment substantially reduced the associated risk of Parkinson’s, suggesting that timely management of sleep apnea may help mitigate long-term neurological risk.

The study emphasises that while the findings show a strong association, they do not prove causation; not everyone with sleep apnea will develop Parkinson’s. Additionally, CPAP adherence could not be fully verified, and the results may not generalise beyond the US veteran population.

Critical link

Nonetheless, the research highlights the critical link between sleep health and brain health and suggests that untreated sleep apnea may be a modifiable midlife risk factor for Parkinson’s disease.

Untreated sleep apnea, particularly obstructive sleep apnea, has been increasingly recognised as a risk factor for Parkinson’s disease.

The repeated pauses in breathing during sleep reduce oxygen levels in the blood and disrupt normal sleep patterns, which can damage nerve cells in the brain, especially in the regions controlling movement and coordination, which are affected in Parkinson’s disease.

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• Health
• Parkinson's disease
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• brain health
• Obstructive Sleep Apnea
• CPAP Therapy
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• JAMA Neurology
• Neurodegenerative Disease
• Sleep Disorders
• Risk Factors
• The hidden connection between snoring
• interrupted sleep and rising global Parkinson’s epidemic

Sleep apnea also promotes inflammation, oxidative stress, and impaired clearance of brain toxins, all of which may accelerate the degeneration of dopamine-producing neurons. In addition, the cardiovascular strain caused by sleep apnea can further compromise brain health, making the nervous system more vulnerable to neurodegenerative processes.

Progressive neurological disorder

Parkinson’s disease is a progressive neurological disorder that severely impacts movement, balance, and daily functioning. It begins with tremors, stiffness, and slowed movement, and over time can cause cognitive decline, mood disturbances, sleep problems, and difficulties with autonomic functions.

While treatments can help manage symptoms, there is no cure, and the disease can drastically reduce quality of life.

By contributing to brain stress and neuron damage, untreated sleep apnea may increase the likelihood of developing Parkinson’s disease, making the management of sleep apnea a potentially important step in reducing long-term neurological risk.

Obstructive sleep apnea (OSA) leads to repeated interruptions in breathing during sleep, lowering oxygen levels in the blood and disrupting restorative sleep.

Chronic oxygen deprivation can damage nerve cells, particularly in regions controlling movement and coordination—the same areas affected in Parkinson’s disease. Sleep apnea also promotes systemic inflammation and oxidative stress, both of which contribute to neurodegeneration.

Disrupts rain’s natural repair processes

Interrupted sleep further disrupts the brain’s natural repair processes. During normal sleep, the glymphatic system clears toxins from the brain, but fragmented sleep can impair this function, potentially accelerating the loss of dopamine-producing neurons.

Additionally, sleep apnea strains the cardiovascular system, increasing the risk of high blood pressure, stroke, and heart disease, all of which can indirectly harm brain health and worsen neuronal degeneration.

Since Parkinson’s disease involves the progressive loss of dopamine-producing neurons, the combination of oxygen deprivation, inflammation, disrupted brain repair, and cardiovascular strain caused by untreated sleep apnea may make these neurons more vulnerable, thereby increasing the risk of developing Parkinson’s disease over time.

Global trends in Parkinson’s disease

Parkinson’s disease rates are rising worldwide. One major reason is that people are living longer, and older age is the strongest risk factor.

As global life expectancy rises, the number of cases naturally increases. However, ageing alone does not fully explain the trend. Age-adjusted rates are also rising, suggesting that environmental exposures and lifestyle changes may be contributing.

Global trends such as industrialisation, urbanisation, and increased pollution may elevate exposure to chemicals or toxins linked to Parkinson’s.

Improved medical awareness, better diagnostic tools, and more accurate reporting may also play a role, as doctors are now more likely to identify previously undiagnosed cases.

Together, these factors have led researchers to predict that the number of people living with Parkinson’s could more than double in the coming decades.

Parkinson’s disease typically arises from a complex interplay of genetic, environmental, and lifestyle factors. Age is the most significant risk factor, with most cases occurring in people in their 60s or older.

Men are more likely than women to develop the disease, and around 10 to 20 per cent of cases have a genetic component, where certain gene changes increase susceptibility.

Environmental exposures

Environmental exposures also play a role, with living or working in areas with pesticides, herbicides, solvents, or heavy metals linked to a higher risk. People in rural areas, those involved in farming, or those exposed to agricultural chemicals are more likely to develop Parkinson’s.

Additionally, repeated head injuries or brain trauma may elevate risk, although evidence is less conclusive.

Because Parkinson’s usually results from a combination of these factors rather than a single cause, predicting who will develop the disease can be difficult.

Globally, Parkinson’s disease is affecting an increasing number of people. As of 2019, over 8.5 million individuals were living with Parkinson’s disease worldwide.

Modelling based on the Global Burden of Disease Study projects that by 2050, this number could rise to about 25.2 million—more than double compared with 2021.

The predicted prevalence is approximately 267 cases per 100,000 people, reflecting both the ageing global population and improved reporting and diagnosis.

The global burden in terms of disability and death is also rising. Parkinson’s accounted for 5.8 million disability-adjusted life years in 2019, and deaths attributed to the disease have more than doubled since 2000.

The incidence of new cases globally is estimated at roughly 15.6 per 100,000 people, age-standardised. These trends are driven by population ageing, better recognition of the disease, and possibly environmental and lifestyle factors.