Understanding the Connection Between Sleep Apnea and Heart Conditions

Researchers have found that obstructive sleep apnea (OSA) is linked to cardiometabolic dysfunction. The study, seen in the Journal of Clinical Endocrinology and Metabolism, attempts to provide an explanation as to why sleep apnea patients often have problems associated with their heart.  Up until this point, researchers have previously been aware of the link between obstructive sleep apnea and other conditions, such as the various forms of diabetes and cardiovascular disease.

However, the connection was unknown as to whether or not one caused another, or if another circumstance existed between the two conditions. Many researchers have questioned if obstructive sleep apnea is a direct cause of heart-related conditions.

Lead researcher Jonathan Jun, MD, discusses this very point when he states that, “Sleep apnea is a common condition that I see on a daily basis as a pulmonary physician… Many of my sleep apnea patients have diabetes and metabolic syndrome. I—and many others before me—have wondered whether OSA is causing these problems, or if OSA is just an ‘innocent bystander’ to obesity.”

Throughout the study, a variety of baselines and distinct characteristics of patients were established in order to better understand the potential association between obstructive sleep apnea and heart-related problems.  One of these traits that researchers utilized in the study included the levels of plasma free fatty acids (FFA), glucose, insulin, triglycerides (TGs), as well as cortisol.  These levels were observed in a total of 31 patients as they slept.  Each patient was analyzed while using (and not using) a continuous positive airway pressure (CPAP) machine. 

The researchers of the study found that the bulk of metabolic function seen in patients diagnosed with obstructive sleep apnea occurred while the individual was awake rather than asleep.  This very finding could have serious repercussions for patients, made obvious when the researchers noted that, “Because sleep comprises one third of the human lifespan, altered metabolism during this period may have substantial health implications.”

The entire population observed in the study were reported as having been diagnosed with either moderate or severe obstructive sleep apnea, with most patients hovering around the age of 50 years old.  Most of the patients being observed in the study were discovered to be white males (which comes as no surprise, as males are more commonly diagnosed with the various forms of sleep apnea relative to women). 

Over 50 percent of the test population was also found to have had a past history of hypertension and hyperlipidemia, in addition to roughly 25 percent having had non insulin-dependent diabetes before the study

In terms of how the study was conducted, Jun and his team observed the patients for a total of four nights of sleep, with each patient having already been used to utilizing a continuous positive airway pressure machine.  For the first two nights, patients made use of the machine, and following this patients were then analyzed for two nights without it.  One conclusion that was reached was that after having not used the continuous positive airway pressure machine for as long as the did, the patients were observed as having a noticeable increase in blood pressure, heart rate, as well as stiffness in the arteries, all of which aided in increasing cardiovascular stress. 

In addition to these findings, the researchers from the study pointed out that obstructive sleep apnea served as a sort of catalyst for an increase in the levels of plasma free fatty acids, cortisol, and glucose.  Because of these changes seen with the study, it was found that the patients being observed also experienced respiratory events, an increased heart rate, disrupted sleep, as well as hypoxemia while the patients slept.

What is sleep apnea?

Sleep apnea consists of a grouping of different types of sleep-related disorders.  The disorder said to affect over 20 million patients in the United States alone, and is commonly recognized as a condition wherein the affected individual receives poor sleep due to obstructed pathways (this however only describes obstructive sleep apnea, and not necessarily the other forms of the sleep disorder).  These other forms of sleep apnea include, as previously mentioned, obstructive sleep apnea, central sleep apnea, and complex sleep apnea.  The most common symptoms of these disorders include headaches experienced upon waking up, loud snoring, struggles staying asleep, irritability, problems focusing, sore throat, as well as brief pauses in breathing while asleep.

While there is currently no finite cure for sleep apnea, a variety of devices exist that help to alleviate some of the symptoms experienced with sleep apnea.  Some companies have been able to offer small devices to serve this function, yet most patients currently use the more bulky continuous positive airway pressure machine, placed next to their bed while they sleep.  Other forms of treatment include certain oral appliances that serve the function of keeping one’s throat open during sleep, as well as expiratory positive airway (EPAP) devices.

The future for sleep apnea patients

The study may be a huge step forward for the progress that is going towards treating the various types of sleep apnea.  This research can enable both the involved scientists and the affected patients to gain important insights into the complexities that come with the sleep disorder. 

This can ultimately be achieved by understanding what pre-existing conditions may increase the likelihood that a patient is diagnosed with some form of sleep apnea.  If the many research efforts prove to be a success, patients will have the knowledge they need to either reverse or prevent the sleep disorder before it becomes prevalent.

While potential discoveries prove to be on the horizon for the population diagnosed with this sleep disorder, treatments currently exist for patients looking to alleviate their respective symptoms. Some of the available options can include tissue removal, repositioning of the jaw, implants (placed inside of one’s palate), as well as creating new air passageways (this is known as a tracheostomy, and is often for more severe cases of sleep apnea).

At the end of the day, one of the best forms of treatment can be to remain diligent with getting the necessary aerobic exercise and eating in a healthy manner.  With the use of such techniques, paired with the exciting research being conducted today, sleep apnea patients are well on their way to a better, more quality life.