The lingering health effects of COVID-19 have become a significant public health concern, with many individuals experiencing prolonged symptoms that affect various body systems, including respiratory and sleep health. Reports of persistent fatigue and unrefreshing sleep following the infection have raised questions about whether the virus can cause or worsen sleep disorders. This article explores the relationship between SARS-CoV-2 infection and sleep-disordered breathing, investigating the evidence linking COVID-19 to the development or exacerbation of sleep apnea.
Understanding Sleep Apnea
Sleep apnea is a common disorder characterized by repeated interruptions in breathing during sleep, which leads to fragmented rest and reduced oxygen levels in the blood. These pauses in breathing, or apneas, can occur dozens of times per hour, severely disrupting the normal sleep cycle.
The most common form, Obstructive Sleep Apnea (OSA), happens when the airway becomes physically blocked or collapses due to the relaxation of throat muscles and soft tissue. A less common type is Central Sleep Apnea (CSA), where the brain temporarily fails to send the proper signals to the muscles that control breathing. Both types result in symptoms such as loud snoring, gasping or choking during the night, and excessive daytime fatigue. A formal diagnosis requires objective monitoring of breathing patterns during sleep.
The Scientific Connection Between COVID-19 and Sleep Apnea
Evidence suggests that COVID-19 infection may both induce new-onset sleep apnea and worsen pre-existing conditions through several biological pathways. The systemic inflammation triggered by the virus, sometimes referred to as a “cytokine storm,” plays a role in this connection. This inflammatory response can lead to swelling and edema in the upper airway tissues, physically narrowing the passage and increasing the likelihood of obstructive events during sleep.
The virus’s potential to affect the nervous system may also contribute to central forms of the disorder. Viral tropism includes neurological structures, and injury to the brainstem could theoretically impair the central control of breathing. Cases of CSA have been reported following COVID-19 infection, pointing toward a possible neurological link.
Changes in body weight and physical activity during and after recovery from the acute infection also influence the risk for Obstructive Sleep Apnea. Increased body mass, especially around the neck, is a well-established risk factor for OSA. This weight gain, combined with the post-viral weakening of respiratory muscles, can collectively contribute to the development or worsening of airway collapse. Studies focusing on patients with persistent post-COVID symptoms, often termed Long COVID, have found a high incidence of new-onset OSA.
Differentiating Sleep Apnea from Other Post-COVID Sleep Issues
Many people recovering from COVID-19 report significant sleep problems, but it is important to distinguish true sleep apnea from other common post-viral sleep disturbances. Long COVID frequently involves symptoms like chronic fatigue, brain fog, and post-exertional malaise, all of which can mimic the daytime sleepiness caused by apnea. However, the underlying mechanism of these symptoms is often different.
Chronic insomnia is highly prevalent post-COVID and is characterized by difficulty falling or staying asleep, leading to generalized sleep deprivation. In contrast, sleep apnea involves repeated breathing cessations, which may not always be consciously perceived by the individual but are physically disruptive to sleep quality.
Specific “red flag” symptoms are more indicative of sleep apnea than general post-viral fatigue or insomnia. These include loud, habitual snoring, witnessed episodes of gasping or choking by a bed partner, and waking up with a dry mouth or a severe morning headache. The presence of breathing-related events points toward a diagnosis of sleep-disordered breathing. Objective monitoring is necessary to confirm if breathing disruption is the cause of the poor sleep quality.
Diagnosis and Treatment Recommendations
For individuals experiencing persistent fatigue and sleep issues following a COVID-19 infection, consultation with a healthcare provider or a sleep specialist is advisable. The symptoms of post-COVID fatigue and sleep apnea overlap significantly, making a clinical evaluation necessary to determine the correct cause. The diagnostic process typically begins with a clinical history and an assessment of risk factors.
To confirm a diagnosis of sleep apnea, a sleep study is required. This may be conducted as a Polysomnography in a sleep laboratory or as a Home Sleep Apnea Test (HSAT). These tests monitor parameters such as airflow, blood oxygen levels, and breathing effort to detect the frequency and severity of apnea and hypopnea events.
A confirmed diagnosis of Obstructive Sleep Apnea often leads to the recommendation of Continuous Positive Airway Pressure (CPAP) therapy. The CPAP machine delivers a steady stream of pressurized air through a mask to keep the upper airway open during sleep. Other treatment options include positional therapy, oral appliances to reposition the jaw, and lifestyle modifications such as weight loss and avoiding alcohol before bed. Treating sleep apnea, whether new-onset or exacerbated by COVID-19, can significantly improve oxygen levels and sleep quality, potentially alleviating some of the persistent fatigue associated with Long COVID.