Sleep apnea involves the repeated cessation of breathing during sleep, causing significant physiological stress. Dizziness is a feeling of unsteadiness, while vertigo is the distinct sensation that you or your surroundings are spinning. Research indicates that individuals with sleep apnea are more likely to experience these balance-related issues.
How Sleep Apnea Triggers Dizziness
The repetitive breathing pauses characteristic of sleep apnea cause immediate, systemic changes in the body’s chemistry and circulation. These nightly events repeatedly plunge the body into intermittent hypoxia, meaning blood oxygen levels drop significantly. This chronic oxygen deprivation stresses multiple organ systems and can lead to dysfunction that manifests as dizziness during waking hours.
Apnea events also frequently cause a buildup of carbon dioxide in the bloodstream, known as hypercapnia, because the body cannot effectively expel the gas. This alteration in blood chemistry disrupts the body’s physiological balance and can contribute to symptoms like confusion or lightheadedness.
The body perceives the drops in oxygen as a threat, triggering an immediate surge in sympathetic nervous system activity, the “fight or flight” response. This activation causes heart rate to accelerate and blood pressure to spike dramatically to compensate for the lack of oxygen.
Studies have shown that blood pressure can increase by 30 to 40 millimeters of mercury during an apneic episode. These nightly, cyclical spikes in blood pressure and heart rate put strain on the circulatory system and can result in lightheadedness or a feeling of unsteadiness upon waking.
Vestibular System and Balance Disruption
The balance problems associated with sleep apnea are often rooted in systemic stress impacting the delicate structures of the inner ear. The vestibular system, located within the inner ear, is responsible for communicating information about spatial orientation and motion to the brain.
Chronic hypoxia and the significant fluctuations in blood pressure can negatively affect the microvascular structures that supply blood to the inner ear. The inner ear’s blood supply is highly vulnerable to vascular changes because it is fed by a single “end artery” with no secondary supply route.
Damage to these small blood vessels due to untreated sleep apnea can lead to vestibular dysfunction. This balance disorder can result in vertigo, or a spinning sensation, and is associated with a higher incidence of specific inner ear disorders like Ménière’s disease and benign paroxysmal positional vertigo (BPPV).
The compromised circulatory regulation also explains why dizziness may be more noticeable when a person with sleep apnea changes position quickly, such as getting out of bed. The body’s inability to rapidly adjust blood flow due to chronic vascular stress makes it difficult to maintain balance during these movements.
Diagnosis and Management for Symptom Relief
A person experiencing persistent dizziness or vertigo should consult a healthcare provider to determine the underlying cause, as balance issues can stem from various sources. If sleep apnea is suspected, the next step involves a formal sleep study, or polysomnography.
Polysomnography is a comprehensive test that monitors several physiological functions during sleep, including brain waves, heart rate, breathing patterns, and oxygen levels. This study provides a definitive diagnosis by calculating the Apnea-Hypopnea Index (AHI), which is the number of breathing cessations and shallow breathing events per hour of sleep.
Treating the underlying sleep apnea is the most effective method for resolving the associated dizziness and vertigo. The most common treatment is Continuous Positive Airway Pressure (CPAP) therapy, which uses a device to deliver pressurized air through a mask to keep the airway open during sleep.
By keeping the airway open, CPAP prevents the drops in blood oxygen and the cyclical blood pressure spikes that cause the physiological stressors. Studies have consistently reported that CPAP treatment often leads to the partial or complete resolution of dizziness in people with sleep apnea.
In cases of mild sleep apnea, alternative treatments such as an oral appliance that repositions the jaw or positional therapy that encourages sleeping on one’s side may also be considered. These treatments work by reducing the frequency of apneas and hypopneas, thereby mitigating the physiological cascade that leads to dizziness.