Sleep Apnea and Heart problems: How Do They Relate?
Obstructive Sleep Apnea (OSA) is the most common sleep-related breathing disorder worldwide, affecting more than a billion people around the globe . It usually causes loud snoring, midnight awakenings and daytime sleepiness.
Sadly, new evidence suggests that OSA not only affects your sleep quality. It can also increase your heart rate and blood pressure, leading to cardiovascular diseases and reduced quality of life in the long term.
But how does this happen? How can you prevent it? We’ll give you a few answers.
Sleep Apnea and Heart Disease
Sleep disorders are more common than people think. It is estimated that around 50-70 million people in the United States have different types of sleep problems, many of whom suffer from obstructive sleep apnea syndrome—according to the American Sleep Apnea Association (ASAA).
Sleep Apnea is a common sleep-related breathing disorder characterized by repetitive episodes of absent or reduced inspiratory airflow (apnea and hypopnea) due to an upper airway obstruction. It affects both men and women of any age, but is more common among older men.
The number of times a person with sleep apnea may stop breathing for up to a minute at a time can vary greatly, ranging from around five times per hour to as many as 100 in rare cases.
The true prevalence of this disorder, sleep apnea, is difficult to determine, considering that most of the patients have not been diagnosed. But some studies (NIH) establish that in North America approximately 15 to 30% of men and 10 to 15% of women suffer from sleep apnea.
In earlier studies (NIH)—between 1990 and 2010—the prevalence used to be around 11 to 14% in men and 4 to 5% in women, causing concern among doctors because sleep apnea diagnosis appear to be increasing over time. This may be related to the increasing rates of obesity in the US, or it may be due to a higher detection rate.
The most common symptoms of sleep apnea are:
1. Loud snoring
2. Repeated episodes of breathing problems during the night.
3. Awakening with a dry mouth.
4. Finding it difficult to stay awake during the morning after a normal night of sleep.
5. Experiencing daytime fatigue and headaches.
6. Waking up with an urge to urinate during night hours.
7. Having a partner that notices that you have breath interruptions during the night.
If you have any of these symptoms you should talk to a sleep medicine doctor. The doctor will conduct a series of tests, among which the most crucial is the sleep study or polysomnography.it records your brain waves, the oxygen level in your blood, your heart rate, and your breathing during sleep. This study is the gold standard for sleep apnea diagnosis.
If after reading the symptoms you have doubts about whether you suffer from sleep apnea, we suggest this Home Sleep Test. During a virtual appointment, the doctor may prescribe a home sleep test if necessary. Then, you will receive the world's smallest home sleep apnea test, the Night Owl is the size of a fingertip and weighs 1 ounce.
But is sleep apnea a disease that only affects you during your sleep period? The answer is no. Even if the direct impact of this disease occurs in the lungs and in your brain (fatigue), there are some associations with kidney, cardiac and metabolic syndromes just like type 2 diabetes.
Sleep Apnea and Heart Health
But what are the effects of sleep apnea in heart health? According to the American Heart Association, obstructive sleep apnea (OSA) has been linked to various cardiovascular complications, including coronary artery disease (which can lead to heart attack), strokes, hypertension, heart failure, atrial fibrillation (an irregular, often rapid heartbeat), other arrhythmias, and sudden cardiac death.
This disorder generates low oxygen levels in blood vessels, which causes a significant increase in sympathetic activity. This, in turn, influences heart rhythm and causes high blood pressure. In the long term, this means the heart has to perform recurrent and intense extra work, leading to hypertrophy and the possibility of heart failure.
There are also changes in the chest pressure—especially in those affected with severe sleep apnea associated with conditions like obesity—causing additional pressures for the heart. Over time, these repetitive changes in intrathoracic pressure can lead to atrial fibrillation, problems with blood flow to the heart, and even heart failure.
Endothelial dysfunction in people with OSA may also play a role in developing heart problems.This is because of the oxidative stress caused by reactive oxygen, which OSA generates when left untreated.
One of the significant challenges shown in the clinical trials is to determine precisely if the increased risk for cardiovascular consequences is due to the OSA itself or if it’s triggered by other common risk factors that are frequent in these patients, such as obesity, high cholesterol levels and hypertension.
Although there is some controversy on how exactly severe OSA can lead to a variety of cardiovascular diseases, there is a wealth of scientific evidence confirming this association. For instance, a meta-analysis of 16 studies showed how severe OSA (AHI ≥30) was associated with increased cardiovascular mortality.
Types of Sleep Apnea and Their Effects on the Cardiovascular System
There are two types of sleep apnea you should know about: OSA (the most common type) and central sleep apnea (less common). Let’s look at their differences and similarities:
Most common (20% of the general population)
Less common (less than 1% of the general population)
Associated with obesity or amygdalitis
Associated with people that have suffered strokes, heart failure or are taking opioid medications
Mechanism of disease
Happens when the muscles in the back of the throat relax. This causes the airway to narrow or close, not letting the air through
The brain fails to send signals to your breathing muscles, causing them to malfunction
Usually found in patients with overweight or obesity
Not related to weight
Relation with CV disease
Cardiovascular problems after developing OSA
Cardiovascular problems before the diagnosis
More prevalent among males than females
More prevalent among males than females
Even if central sleep apnea has not been associated with the worsening of previous cardiovascular diseases, there is a big chance that it can negatively impact the atrial and ventricular parts of the heart. Since CSA is not the most prevalent type of sleep apnea research studies have been limited, but we cannot forget that this condition causes hypercapnia, oxidative stress and increased sympathetic tone.
Regarding OSA, there is a vast amount of scientific evidence, involving thousands of patients, that connects it with different heart conditions:
Obstructive Sleep Apnea and Coronary Artery Disease
Coronary artery disease (CAD) is a complex and significant clinical problem that is considered the leading cause of death in the US right now. This disease can be described as a damage in the heart muscle known as myocardium, due to a big demand of oxygen that exceeds the oxygen supply that has been delivered to the heart. This can lead to necrosis (death) of the cardiac tissue and has been strongly linked to atherosclerosis and hypertension.
OSA may increase the risk of coronary events. During an apnoeic event there is increased breathing work, considerable negative intrathoracic pressure, and recurrent hypoxia or reoxygenation, which result in oxidative stress and systemic inflammation.
All this can contribute to worsen coronary atherosclerosis (gradual buildup of plaque in the walls of your arteries made of fat, cholesterol, calcium and other substances), and increase the chance of acute myocardial infarction (MI) events.
OSA and Atrial Fibrillation
Atrial fibrillation (AF) is the most common type of cardiac arrhythmia, affecting around 2% of people younger than 65 years old and about 9% of people of ages 65 and older. It is associated with an increased risk of developing strokes, so it’s important to treat it in the early stages.
Different clinical trials have suggested that OSA could be related to AF; however, these studies might be confounding and whether the relationship is causal remains unclear. Most doctors believe that gas exchange abnormalities in OSA patients, characterized as intermittent hypoxia and hypercapnia coupled with the chronic recurrence and abrupt negative changes in intrathoracic pressure can negatively impact the heart structure.
There is a high likelihood that this sleep disorder may lead to structural and functional atrial remodeling (change in the cellular architecture of the superior cavities of the heart) leading to rhythm changes.
OSA and Sudden Cardiac Death
Sleep plays an integral role in maintaining health and quality of life, and healthy sleep acts as an effective protector for the cardiovascular system: it reduces heart rate, blood pressure and the possibility of cardiac effort or remodeling. So a chronic disruption can lead to a CV problem.
Sudden cardiac death (SCD) is defined as an unanticipated natural death from cardiac pathology 1 hour or less from symptom onset, in a person without any prior condition that would appear lethal. And it is not a secret how OSA through the high intrathoracic pressure can increase myocardial oxygen demand and precipitate cardiac ischemia.
It is important to clarify that having OSA does not mean that you will die suddenly with a cardiovascular problem; but the chances are higher in comparison with the general population without the disorder.
Treatment for Sleep Apnea
Even if sleep apnea sounds like a dangerous and complex problem, the treatment options are simple and easy to implement.
First of all, to reduce sleep apnea and the risk of heart disease you can apply changes in your lifestyle. These can include weight loss, and eating healthy foods that can decrease cholesterol and triglycerides like salmon, tuna, and halibut—these are heart-healthy foods due to their high levels of omega-3 fatty acids. Also, regular exercise can help you have a healthier body and mind.
Continuous positive airway pressure (CPAP) therapy prevents respiratory collapse events by maintaining a positive airway pressure so no obstructions will occur while you sleep, reverting the problem during the entire night.
CPAP machines are very popular as a method for treating sleep apnea and ensuring a restful sleep. These machines use a hose connected to a mask or nose piece to deliver constant and steady pressurized air flow into the nose and mouth via an attached tube and mask.
CPAP therapy is highly effective in improving your sleep apnea: it prevents your blood oxygen levels from falling during sleep, and allows you to get a more restful sleep, reducing the risk of cardiovascular diseases.
If you already suffer from a cardiovascular illness like heart failure or hypertension, you need to visit a cardiology doctor to avoid progression and receive a personalized treatment; but including these machines in your sleep routine will definitely have a positive impact in the long term.
These machines are very user-friendly, even for first time users. However, some patients might need more time to get used to the noise, dry mouth or leaky masks. In Sleeplay we have tier top CPAP machines that won't cause discomfort at all. Some are equipped with a heated humidifier, so you won't be waking up in the middle of the night due to feelings of dryness in the mouth. Others are completely silent during night, and we offer different choices of masks to avoid any irritation or discomfort.
Definitely sleep apnea is a disorder that not only impacts your rest, but that can also affect many organs including the heart. Medical science has proved that obstructive sleep apnea affects the structure of the cardiac muscle dramatically, which could lead to infarction, failure and arrhythmias if not treated.
Luckily, there are some lifestyle changes you can apply to stop the progression. And additionally getting sleep apnea treatment is easy through CPAP machines. They will maintain your airway open during the night, but you need to buy a good equipment that will be still operative in time and won't bother you at all.
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