Severe Obstructive Sleep Apnea: Symptoms, Risks and Treatment Options

Most adults need at least seven hours of good night’s
sleep.¹ While you sleep, your body repairs damaged cells and
releases important hormones. Sleep also gives your heart a chance to
slow down and rest.² As a result, getting quality sleep is
important for your overall health and well-being.

While sleeping, some people may experience shallow or temporary
pauses in breathing.— also known as sleep apnea. Sleep apnea can cause a
person to repeatedly wake up throughout the night, making it difficult
to get a restful night’s sleep.

If these pauses happen more often or last longer during the night,
they may point to a more serious form of sleep apnea called severe
obstructive sleep apnea (OSA). When untreated, severe OSA can have
serious effects on your long-term health.³

Learning more about severe OSA — including its health risks and
treatment options — is a great first step toward meaningful
conversations with your doctor.

Understanding sleep apnea and severe sleep apnea

Across the world, sleep apnea affects over 1 billion people of all
shapes, sizes, genders and ages.⁴ And more than 80% of people
living with moderate severe sleep apnea are undiagnosed.⁵
Learning more about sleep apnea and understanding when the condition
becomes severe can help you take charge of your sleep quality and
health.

What is sleep apnea?

Sleep apnea is a condition that causes a person’s breathing to stop
and start many times during sleep.⁶ These pauses in breathing
may make it difficult for your body to get enough oxygen.

The most common symptoms of sleep apnea include:

• Excessive daytime sleepiness.
• Morning headaches.
• Feeling irritable or moody.
• Difficulty concentrating, struggling to feel present during the
  day.
• Snoring or gasping for air while you sleep.

Types of sleep apnea

Sleep apnea is broadly categorized into two main types, each with
distinct underlying symptoms.⁷

• • Obstructive sleep apnea (OSA) is the most common type of sleep
    apnea. The muscles around the throat relax to the point of
    collapse,⁶ restricting airflow during sleep. Breathing may
    become shallow or stop for seconds to minutes at a time.
  • Central sleep apnea (CSA) occurs when your brain doesn’t send
    normal signals to the muscles that control breathing, causing breathing
    to pause during sleep.

How common is OSA?

OSA is a common sleep condition. OSA prevalence is generally about
two to three times higher in men, although the difference narrows with
age, particularly after menopause. ⁴

It’s also a growing challenge in the U.S. Researchers believe OSA
will impact around 77 million people in the U.S. by the year
2050.⁸ That’s an increase of around 35% in 30
years.⁸ The study also suggests that:

• 30.4 million women may have OSA by 2050, which is an increase of
  65% over 2020 numbers.⁸
• 45.9 million men may have OSA by 2050, which is an increase of
  19% over 2020 numbers.⁸
• New drugs expected to positively impact OSA treatment results may
  only reduce these figures by around 4%, suggesting that OSA will remain
  a significant challenge.⁸

Early diagnosis and treatment of OSA may help reduce the severity of
symptoms and lower the risk of related health concerns in the
future.⁹ If you experience symptoms of sleep apnea, it’s
important to talk to your doctor. They may have you take a sleep test to
help get answers about what’s happening while you sleep.

What is considered severe obstructive sleep apnea?

When you take a sleep test, you’ll receive an apnea-hypopnea index
(AHI) score.¹⁰ The term ‘apnea’ means you stop breathing for
at least 10 seconds during sleep. ‘Hypopnea’ is when you have a partial
blockage of your airway, so your breath is more shallow than normal. So,
your AHI tells you how many times your breathing became shallow or
paused entirely during each hour of sleep. The higher your AHI, the more
severe your OSA.

The apnea-hypopnea index (AHI) indicates the severity of obstructive
sleep apnea. AHI scores are grouped in the following ranges:

• Normal: AHI < 5
• Mild: AHI of 5 to 14
• Moderate: AHI of 15 to 29
• Severe: AHI of 30 or higher

Severe OSA is concerning because it’s linked to lower-than-normal
oxygen levels. If your oxygen level drops below 90% during sleep, you
may experience serious health issues.¹¹

Normally, blood oxygen levels while sleeping range from 96% to 100%.
For people with sleep apnea, these levels can drop significantly —
sometimes to lower than 88%.¹¹ Your heart, lungs and brain
all run on oxygen. When oxygen levels drop, your body feels it. Repeated
drops in blood oxygen during sleep cause tissue to weaken, and tissues
can weaken, and in severe cases, cells may start to die.¹²
This lack of oxygen is why sleep apnea is associated with serious health
conditions, such as:¹²

• High blood pressure
• Heart disease
• Diabetes
• Obesity
• Depression
• Stroke
• Kidney disease

Risk factors for severe OSA

Approximately 15% of all adults in the U.S. have severe obstructive
sleep apnea (OSA).¹³ Certain factors that may increase your
risk of severe OSA include:¹⁴

• Obesity. People with excess weight may have
  increased risk of severe OSA. Individuals with obesity can have more fat
  deposits in their neck, which can block the upper
  airway.³⁴
• Sex. Severe sleep apnea is more commonly seen in
  men and is often diagnosed at an earlier age than
  women.⁴
• Neck size. People with a larger than average
  neck — greater than 17 inches for men and 16 inches for women — may have
  a higher risk of severe OSA.¹⁵
• Certain health conditions. Heart-related
  conditions, Type 2 diabetes, asthma and chronic obstructive pulmonary
  disease (COPD) are related to a higher risk of severe OSA.
• Smoking and drinking. Smoking can cause
  inflammation in your airway, which affects breathing. Drinking alcohol,
  especially before bed, can cause the muscles in your throat to relax and
  possibly collapse into your airway.¹⁵
• Physical characteristics. A narrow airway, a
  large tongue or a different jaw structure can make it more likely for
  your airway to become blocked.¹⁵

Special populations

Severe obstructive sleep apnea (OSA) risk may vary by population. For
instance, some pregnant women develop OSA due to hormonal changes and
weight gain.¹⁶ Hormonal changes may also cause OSA in women
going through menopause and put them at a higher risk for severe
OSA.¹⁷

Even race has an impact on your likelihood of developing OSA. The
condition is much more common in Black adults than it is in non-Hispanic
White adults.¹⁸ Research suggests that severe OSA is more
common in minority populations. While certain risk factors exist, severe
OSA can and does impact a wide variety of people regardless of gender,
size or race.

Health consequences of severe obstructive sleep apnea

Left untreated, severe obstructive sleep apnea can impact your health
and day-to-day function.

High blood pressure

Some people living with severe OSA may also be living with or may
develop high blood pressure (hypertension). Research suggests that
severe OSA can make it more difficult to control blood pressure.

Cardiovascular complications

OSA is common across cardiovascular disease—affecting up to 40%–80% of people with cardiovascular conditions.²⁰ Severe obstructive sleep apnea may also increase the risk for these heart-related conditions:

• Heart failure. OSA and heart failure have a
  two-way relationship. OSA can make heart failure worse, and heart
  failure can make OSA worse.¹⁹
• Arrhythmias. An arrhythmia is when the heart
  can’t maintain its normal rate or rhythm.²¹ Arrhythmias may
  increase the risk of sudden cardiac death.
• Stroke. The risk of stroke can rise as OSA gets
  worse.²²
• Pulmonary hypertension. Over time, low oxygen
  levels may increase the risk of pulmonary hypertension. This occurs due
  to an increase in the blood pressure of the lungs.²³

Metabolic dysfunction

Severe obstructive sleep apnea (OSA) can make it harder for your body
to manage blood sugar levels. OSA has also been linked to increased
insulin resistance. These are two characteristics associated with
metabolic syndrome, which is a group of conditions that raise your risk
for heart disease, diabetes and other serious health
issues.²⁴

Severe obstructive sleep apnea may also increase the risk for these
metabolic issues:²⁴

• Liver disease
• High cholesterol and/or lipid levels
• Weight gain

Mental health impact

Severe obstructive sleep apnea can even affect your ability to focus,
think, solve problems and remember things.²⁵ Excessive
daytime sleepiness may lead to brain fog, difficulty concentrating,
forgetfulness or related symptoms. OSA has also been linked to
depression and anxiety.²⁵ Research suggests that the risk of
depression increased with higher apnea-hypopnea index (AHI) scores,
indicating a relationship between the severity of OSA and
depression.²⁶

Changes to your mental health may make it difficult to get through
the day and may affect your social and professional life. In addition,
people with severe obstructive sleep apnea have a 123% increased risk of
vehicle crashes compared to people who don’t have sleep
apnea.²⁷

Risk of death

People with untreated severe obstructive sleep apnea have a 3 times
higher risk of dying for any reason compared to people who don’t have
sleep apnea.²⁸ In one study, 42% of the participants with
severe sleep apnea died of stroke or cardiovascular
disease.²⁹

Early diagnosis and treatment may help reduce the risk of death in
people with severe obstructive sleep apnea. Treating OSA early and
sticking with your treatment may help reduce symptoms and support
healthier physical and mental well-being.

Management of severe obstructive sleep apnea

Severe obstructive sleep apnea may affect your health negatively, but
there are effective treatment options available.

Primary treatment approaches

Continuous positive airway pressure (CPAP) therapy is a sleep apnea
treatment that helps people breathe while they sleep.³⁰ It
uses a small machine placed by your bed to gently deliver a steady flow
of air through a mask. CPAP is a drug-free treatment with zero
medication-related side effects. A typical CPAP system includes three
parts: a CPAP device, a flexible tube, and a mask that fits over your
nose or over both your nose and mouth. The gentle air pressure helps
keep your airway open, so you can breathe steadily throughout the night.
When used as directed, it can help alleviate OSA symptoms after the
first night of use.³¹

By helping you get quality, uninterrupted sleep, CPAP therapy can
lead to various health benefits, like improvements in your mood, focus,
memory, productivity, and energy levels.

Surgical approaches

Surgery is invasive, so it’s reserved for people who’ve tried CPAP
therapy without success. For severe OSA, a doctor may recommend one of
the following surgeries to help widen the airway, including:

• Uvulopalatopharyngoplasty (UPPP). UPPP may help
  by removing excess tissue from the throat.³²
• Hypoglossal nerve stimulation. This procedure
  uses an implantable device to push the tongue forward during
  sleep.³³
• Maxillomandibular advancement. This surgery
  adjusts the position of the jaw to create more space in the
  airway.³²

Lifestyle modification and alternative approaches

When paired with a trusted treatment like CPAP therapy, certain
lifestyle changes may make severe OSA symptoms more manageable.

Good nutrition and regular exercise can help with weight management,
preventing airway collapse caused by excess tissue. Avoiding alcohol and
maintaining good sleep habits may also be helpful. We
recommend sleeping on your side instead of your back or stomach.

Because of the serious health risks associated with severe OSA,
lifestyle changes alone are not enough. Treatment for severe sleep apnea
should always be guided by a doctor to ensure safety and
effectiveness.

Looking to learn more about your sleep in general? Take the sleep assessment.

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