Obstructive Sleep Apnea and Heart Disease: The Risk of Sudden Cardiac Death

December 3, 2021

Obstructive sleep apnea (OSA) is such a severe disorder because—on top of leading to a worse quality of life—it is associated with several chronic health concerns, like depression, anxiety disorders, dementia, diabetes, and more. Those who have OSA are dramatically impacted by their inability to sleep well throughout the night, and it’s clear that these individuals need access to excellent treatment options.

Recent studies also suggest a connection between obstructive sleep apnea and heart disease. More specifically, these studies have established an association between OSA and an elevated risk of cardiovascular mortality and sudden cardiac death compared to the general population. Sudden cardiac death (SCD) is an issue that leads to over 300,000 deaths every year in the United States, and it may relate to OSA more than initially expected. This is because various comorbidities affecting those with OSA likely play a significant role in the risk of sudden death in these individuals. Researchers have found that those with OSA are 2.5 times more likely to experience sudden cardiac death between 12 am and 6 am than those without it.

Do you want to learn more about why a sleep disorder like OSA can affect the body so seriously? Let’s get into the connection between OSA and the risk of sudden cardiac death, including why this occurs and how medical professionals can help patients access excellent OSA treatment.

How Low Blood Oxygen Levels Contribute to SCD

One of the most telling characteristics of OSA is intermittent hypoxia, which describes the state that occurs when sufficient amounts of oxygen are not available at the tissue level for the body to maintain homeostasis. This is often the result of low oxygen content in the blood, and any saturation level below 90 percent is considered harmful. Intermittent hypoxia is considered a high-risk stimulus, thought to initiate not only cardiovascular but also respiratory, metabolic, and cognitive deficiencies.

Along these lines, hypoxemia—another word to describe low oxygen levels in the blood—is a strong predictor of sudden cardiac death. According to one five-year study of over 10,000 people, low blood oxygen was one of the biggest determinants of SCD, independent of other well-established risk factors, such as comorbidities like cardiovascular disease, hypertension, and age. The analysis showed that even the lowest nocturnal oxygen saturation predicted an 81 percent increase in the risk of SCD. On top of that, those older than 60 years old who had an AHI above 20 and mean nocturnal oxygen saturation of less than 93 percent had the highest risk of experiencing sudden cardiac death.

The Role of Arrhythmias in OSA and SCD

OSA is ubiquitous among those with cardiac rhythm disorders. Acute mechanisms like the generation of negative intrathoracic pressure, intermittent hypoxia, and surges in the body’s sympathetic response could explain why OSA contributes to arrhythmias. These responses can all stress the heart mechanically, increase inflammation, and cause unhealthy changes in blood vessels. Because those with OSA are also more likely to experience arrhythmias, they may also have a higher likelihood of experiencing sudden cardiac death.

One study from April 2021 looked into the relationship between OSA incidence and severity by monitoring 94 patients with suspected sleep apnea. It found that those with confirmed OSA experienced more frequent episodes of ventricular arrhythmias as well as supraventricular tachycardia (SVT), a condition where your heart beats much faster than average. Similarly, the study’s analysis suggests that the higher an individual’s AHI score was, the more directly associated it was with SVT and the number of pauses longer than 2.5 seconds in ECG monitoring. These irregularities in heart rate are more alarming than they may seem; for some patients, sudden death is more likely to be caused by these, not heart attacks.

Signs You May Have OSA

Clearly, OSA can dramatically influence a person’s quality of life, and it may even lead to death. The connection between obstructive sleep apnea and heart disease is just one cause for concern. And these are just a few of the reasons why the screening and treatment of this disorder is such an important issue. Millions of Americans struggle with OSA, and even more alarmingly, it is estimated that over 80 percent of them have not received a diagnosis. This means that millions of silent sufferers don’t know why they aren’t feeling great or performing well in their daily lives.

Some of the most common symptoms of OSA include the following:

  • Loud snoring
  • Daytime sleepiness
  • Waking up short of breath
  • Stopped breathing during sleep
  • Fatigue
  • Waking up frequently to urinate throughout the night
  • Chest pain during sleep

If you worry you may have OSA or experience any of these symptoms, please consider talking to your doctor. In the case that you might have the disorder, a visit to a sleep medicine specialist may be just what you need to improve your sleep and overall quality of life every day.

How Medical Professionals Can Give OSA Patients Great Treatment

There is no better time for medical and dental professionals to work together to address OSA in their patients. According to the ADA, dentists are in the best position to screen for sleep apnea, as well as provide oral appliance therapy—an excellent alternative for those looking for an alternative to CPAP therapy. Dentists are especially encouraged to play the following roles in OSA:

  • Assess patient risk for disorders and refer patients to appropriate physicians
  • Evaluate the use of oral appliance therapy and provide it for mild and moderate OSA when CPAP fails
  • Communicate treatment progress with patients’ other healthcare providers
  • Identify and address the side effects of oral appliance therapy

By combining treatments and working together to help patients with OSA, dentists and medical providers can make all the difference for millions of individuals who suffer every day with the disorder—knowingly or unknowingly.

Not only is OSA associated with daily pain points like excessive daytime sleepiness and fatigue, but it is also connected to several serious, chronic conditions: dementia, diabetes, depression, anxiety, and cardiovascular disease. Similarly, obstructive sleep apnea and heart disease are also associated with an elevated risk of sudden cardiac death due to its influence on the body’s functions. If you suspect you have OSA, reach out to your doctor today. You don’t have to continue suffering silently.