Hypertension is one of the most common health concerns in the U.S., with nearly 1 out of 2 American adults — or more than 100 million people — suffering from it.
The impact of hypertension can sometimes take years to fully manifest, but the damage can be severe; hypertension is strongly connected to heart disease, heart failure, stroke and erectile dysfunction. There is also a close link between problems getting a good night’s sleep and hypertension, with research indicating up to 50% of people suffering from hypertension also have sleep apnea.
Yet hypertension remains a silent menace for millions. It also contributes to hundreds of thousands of fatalities each year, with about 500,000 deaths in the U.S. in 2017 reporting hypertension as a primary or contributing cause, according to the CDC.
With that in mind, it’s worth reviewing some key points about hypertension — including how often sleep apnea plays a major role in this dangerous issue.
To better understand the connection between high blood pressure and obstructive sleep apnea and why it’s so important to determine whether it’s an underlying cause is because, without treatment, it’s difficult to control even with medication and lifestyle changes. Which means your heart health will suffer.
What Hypertension Means
Hypertension is best known by its colloquial term: high blood pressure. You’re likely familiar with it, but what it means and how it works might escape you. Luckily, hypertension isn’t too hard to understand. Here’s what you need to know about it — and how it can negatively impact your body.
Where Hypertension Occurs
Hypertension impacts the heart and your arteries.
Your blood pressure is created by your heartbeat, which pumps oxygenated blood throughout your body.
High blood pressure/hypertension occurs when the blood pushing against your arteries is too strong; over the long-term, the friction of your blood pressing against your artery walls hurts the soft tissues inside the arteries. This causes cholesterol to form plaque that masks the cuts in the artery walls. The more plaque inside your arteries, the tighter they become, which only raises blood pressure further.
Blood pressure has two distinct factors:
- Your systolic pressure happens when your blood is pumping out of the heart and entering your arteries, which takes the blood to different parts of your body
- Your diastolic pressure is the measure of the rest between your heartbeats
These are represented on a blood pressure gauge, with systolic pressure on top and diastolic pressure on the bottom.
Hypertension is defined by specific blood pressure readings. There are two stages of hypertension:
- Stage 1 hypertension is blood pressure anywhere from 130-139 on top and 80-89 on bottom. For example, blood pressure of 135/85 mmHg would be stage 1 hypertension.
- Stage 2 hypertension is classified as blood pressure of more than 140/90 mmHg.
Stage 2 hypertension is typically treated by a combination of medication and lifestyle adjustments.
How Hypertension Affects Your Body
Hypertension contributes to a number of severe health issues that can lead to a disability or shorten your lifespan.
Here is a look at just a few of the major ways high blood pressure can cause severe health problems:
- Aneurysm: The long-term impact of blood pushing through weakened arteries can lead to a section of the artery wall bulging. This is called an aneurysm, and is most commonly found in the aorta, the largest artery in the body. An aneurysm can burst and lead to potentially fatal internal bleeding.
- Heart Attack: Hypertension can overwhelm the heart, as it struggles to direct oxygenated blood throughout the body. In this case, the heart is simply working too hard over a long period of time to keep up its pace. The heart eventually gives in, resulting in heart failure.
- Stroke: Brain cells die when the brain is deprived of oxygen. High blood pressure can cause blood vessels to rupture or narrow, which can both negatively affect oxygen flow to the brain. Hypertension can also lead to blood clots in your arteries, blocking oxygen flow to the brain and potentially causing a stroke.
- Erectile Dysfunction: One of the earliest signs men suffer from hypertension is erectile dysfunction. About 30 million American men suffering from hypertension also complain of E.D. High blood pressure can restrict blood flow to the penis, as the heart works to pump oxygenated blood cells to different parts of the body.
Again, the major health problems that can stem from high blood pressure can also take years to rear their ugly head. Obviously, it’s best to not wait until that point. Here are a few common hypertension symptoms to keep in mind when considering if hypertension is an issue for you, including:
- Chest Pain
- Instability or dizziness
- Vision problems
- Difficulty breathing
These symptoms often affect people who suffer from sleep apnea as well.
How Sleep Apnea Contributes to Hypertension
Like with many other health concerns, obstructive sleep apnea is linked to hypertension and can exacerbate the issue, making it far worse and difficult to manage, even when taking medication.
Many people who experience high blood pressure discover its possible connection to sleep apnea, but many do not. Although the connection between the two is known in the medical community, that message doesn’t always make it to those most affected.
If you suffer from hypertension, and have been diagnosed with sleep apnea but aren’t adhering to your treatment protocol, you’re putting your heart health at risk.
If you suffer from hypertension but aren’t sure if sleep apnea is a contributing cause, getting an evaluation to rule it out is important.
A telltale sign sleep apnea is compounding your hypertension is when many of the normal solutions for high blood pressure, like getting more exercise and implementing a healthier diet, don’t work. In this case, if you snore during the night, there’s a strong likelihood your hypertension won’t be alleviated unless your sleep apnea is also handled. This is where seeing a doctor about your sleep apnea becomes especially important.
Sleep Apnea Creates Norepinephrine (Adrenaline) Spikes in the Body
One key point to remember is that sleep apnea restricts your breathing. This manifests itself in an airway blockage that most often leads to the loud snoring that is typical for those suffering from sleep apnea. The blocked airway restricts how much oxygen enters the body — something that puts added stress on your cardiovascular system.
When the airway is blocked or constricted at night when you’re asleep, your body must find a way to open up the airway so you can breathe. It does this by releasing norepinephrine (adrenaline). Norepinephrine (norepi) is the main awake neurotransmitter in the brain, and it arouses the brain to signal the throat to open up and let air in.
Although most people don’t actually wake up, the arousal is enough to increase the muscle tone in the throat and return it to how it normally is during the day.
So, what’s the problem with releasing norepinephrine all night with these respiratory events?
It’s a problem because the release of norepinephrine raises blood pressure. In fact, it’s the most powerful agent we have to raise blood pressure. If you’re in shock in the ICU, meaning your blood pressure is so low you’re going to die, you’ll be put on an infusion of norepinephrine to raise it. That’s how powerful it is in raising blood pressure.
The more frequently you have these respiratory events at night, the more norepinephrine you’re going to release, and therefore, the more likely it is to raise your blood pressure. So now imagine you’re trying to keep your blood pressure in control, only all night long your body needs to release the very thing that keeps it high to keep you breathing. It’s a lose lose, unless you treat your sleep apnea.
Sleep Apnea Forces the Heart to Work Harder
The airway blockages created by obstructive sleep apnea also cause your blood pressure to increase because the heart is working harder to get oxygenated blood flowing throughout the body.
While you’re asleep, sleep apnea triggers the brain to pump more blood to key areas like the brain and heart. This puts added pressure on your artery walls, though, and pushes your blood pressure higher than if you were breathing normally while asleep.
The extra pressure it puts on your heart to pump blood and the continuous release of norepinephrine throughout the night also leads to many of the more daunting health problems that stem from hypertension, including heart disease, stroke, erectile dysfunction, and diabetes.
Does CPAP Treatment Help High Blood Pressure?
Research indicates treating sleep apnea can lead to dramatic improvements for those suffering from hypertension.
One study, led by Dr. Claudia Korcarz of the University of Wisconsin’s Atherosclerosis Imaging Research Program in 2014, looked at the impact CPAP (continuous positive airway pressure) machines have on blood pressure. The results showed CPAP therapy – one of the most common and effective treatments for obstructive sleep apnea – dramatically reduced high blood pressure.
After three months of CPAP treatment, participants who used their machine for approximately 6 hours each night reported both reduced hypertension and increased artery size. Two more observations pointed to how important CPAP was in regulating hypertension: for participants who stopped using their CPAP machines, their blood pressure started to increase after only one week; and for participants who didn’t use their CPAP machine consistently, averaging about 2.5 hours of use each night or less, there were no significant improvements in hypertension.
What makes CPAP so effective in treating hypertension is that it removes the catalyst for high blood pressure. By tackling the airway blockages that lead to arousals during the night, CPAP blocks the production of nighttime norepinephrine – and, in the process, stops blood pressure from rising. In other words: CPAP doesn’t actually lower blood pressure, it prevents the events that lead to blood pressure increasing.
The study highlighted what many other researchers have found — that treatment for obstructive sleep apnea can lead to noticeable improvements for those suffering from hypertension.
Next Steps to See if Sleep Apnea Is Impacting Your Blood Pressure
If your blood pressure is routinely over 130/80 mmHg and you also suffer from poor sleep, it’d be worthwhile for you to reach out to your doctor and set up a sleep study. The solution could simply be a consultation away.
Remember, obstructive sleep apnea and hypertension are closely related, with about half of all people suffering from high blood pressure also dealing with O.S.A. Sleep apnea is hard enough on the body; it’s not worth having the major repercussions of hypertension, like heart failure and stroke, also keeping you up at night worried.
Here’s an easy, useful Sleep Quiz we offer that will help you determine whether sleep apnea is stopping you from getting a good night’s sleep.
And if you’re ready to discover how a sleep specialist can help you, contact Sleep Centers of Middle Tennessee today and we can get you set up for better sleep.
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Nunes, K.P., et al. (2012). New Insights Into Hypertension-Associated Erectile Dysfunction.
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Korcarz, Claudia, et al. (2014). Continuous Positive Airway Pressure Rapidly Improves Blood Pressure and Arterial Constriction in Young Adults. Retrieved on February 10, 2020 from: