Interrupted sleep, chronic fatigue, hypertension, palpitations, and problems with concentration. Many people dismiss these symptoms, attributing them to stress or the natural effects of aging. Yet they may signal obstructive sleep apnea (OSA) – a condition affecting hundreds of millions worldwide, often going undiagnosed for years.
A team of researchers from Wroclaw Medical University has demonstrated that sleep apnea is not only a matter of anatomy or excess weight, but also a complex interplay of neurobiology and genetics.
Breathing controlled by the brain
Until now, OSA was mainly associated with physical narrowing of the airways – flaccid throat muscles, a large tongue, a thick neck, and enlarged tonsils. But breathing is also a complex process regulated by the nervous system. One of the key neurotransmitters is dopamine – usually linked to motivation and reward, but also influencing muscle tone and sleep rhythm.
“Dopamine is a kind of regulator – it governs not only emotions and concentration but also how the brain controls breathing at night,” explains Dr. Joanna Smardz, lead author of the study.
What did the researchers in Wroclaw discover?
The project examined over 150 individuals for dopamine levels in the blood and nearly 300 people for genetic variations in three genes – COMT, DRD1, and DRD2, which are responsible for dopamine metabolism.
The most important findings were clear:
- patients with OSA had higher dopamine levels than healthy individuals,
- the T allele in the DRD2 gene (rs1800497) turned out to be an independent predictor of more severe disease, associated with a higher number of apneas, arousals, and worse oxygenation,
- risk was significantly higher in men and older individuals.
“This is the first study of its kind to show that dopaminergic genes genuinely affect the course of sleep apnea,” emphasizes Dr. Smardz.
Why is this discovery groundbreaking?
For years, OSA was seen as a mechanical problem. The Wroclaw study shifts the focus, showing that the condition also has neurobiological and genetic foundations.
“We are witnessing the beginning of a new paradigm. In the future, a snoring patient may be diagnosed not only with polysomnography but also with biochemical and genetic tests. This is in line with the philosophy of precision medicine,” notes Prof. Mieszko Więckiewicz, co-author of the study.
This opens the way to:
- new biomarkers – e.g., blood tests or genetic testing to identify high-risk individuals,
- personalized treatment – tailoring therapy more closely to the patient’s profile,
- drug research targeting the dopaminergic system as a supplement or alternative to CPAP.
Not just sleep apnea
The role of dopamine in sleep disorders is not surprising – it has long been linked with restless legs syndrome, narcolepsy, or Parkinson’s disease. The list now extends to include obstructive sleep apnea.
“We can speak of a common mechanism linking different diseases – hypoxia, oxidative stress, and neurotransmission disorders,” stresses Dr. Smardz. “That is why sleep diagnostics should be interdisciplinary – involving internists, pulmonologists, neurologists, cardiologists, ENT specialists, dentists, and psychiatrists.”
What does this mean for patients?
Although genetic tests and dopamine level measurements are not yet standard, researchers do not doubt that this is the future of sleep medicine. They will allow earlier risk detection, more effective therapy monitoring, and truly personalized treatment.
Snoring should not be ignored, as it may be a symptom of a disease that lowers quality of life and increases the risk of heart attack or stroke.
This text is based on the article: The importance of dopamine levels and single-nucleotide polymorphism within the COMT, DRD1, and DRD2 genes in obstructive sleep apnoea
Authors: Joanna Smardz, Helena Martynowicz, Marta Dratwa-Kuzmin, Anna Wojakowska, Paweł Gac, Katarzyna Bogunia-Kubik, Mieszko Więckiewicz