What are the serious health risks associated with obstructive sleep apnea (OSA)

When you have obstructive sleep apnea (OSA), you're at a higher risk for serious health problems like stroke, heart attack, type 2 diabetes, obesity and depression – along with a shortened lifespan. Likewise, having one of these conditions can increase your chances of developing the sleep disorder.

But what does that really mean – and how does untreated sleep apnea contribute to those risks? And, vice versa, how can those conditions worsen sleep apnea?

In this article, we’ll walk through the key health risks linked to obstructive sleep apnea to better understand why treating sleep apnea – and managing related medical conditions – is so important.

Quick recap of what obstructive sleep apnea is

Obstructive sleep apnea is a serious sleep disorder where your breathing stops and starts during sleep. These “sleep apnea events” happen when your throat muscles, including your tongue, relax and block your airway. When that happens, you briefly wake up to take a breath, though you might not remember it. The number of sleep apnea events you have indicates the severity of the disorder:

• Mild: 5-14 times per hour

• Moderate: 15-30 times per hour

• Severe: more than 30 times per hour.
  

Over time, the ongoing breathing interruptions make it harder for your body to get enough oxygen. This puts stress on your vital organs, including your heart, lungs and brain. These interruptions also disrupt your sleep – and even as few as five events per hour can keep you from getting the quality rest needed to support overall health and well-being.

While each person may have different experiences with OSA, common signs and symptoms include:

• Stopping breathing, snoring or gasping for air during sleep

• Frequently waking up with a dry mouth, sore throat or headache

• Feeling exhausted, falling asleep or napping during the day

• Finding it hard to focus or remember things

• Frequently getting common colds

• Decreased sex drive

• Behavior and attitude changes, like mood swings, irritability or quick temper
  

The importance of uninterrupted sleep

Sleep helps keep your brain, heart and immune system in shape. It also helps recharge your energy, keep you alert, balance your emotions and behavior, solve problems, make decisions, store memories and much more. To get the full benefit of sleep, adults cycle through four stages of sleep four to six times per night. Each stage has a specific “housekeeping” role in recovery and maintenance for your mind and body. A full sleep cycle – getting through all four stages – usually takes 90 minutes to two hours.

For adults, it’s generally recommended to get seven to nine hours of quality sleep per night. Without it, your body and mind miss these important housekeeping cycles, and your overall health and well-being can begin to suffer.

In addition to causing day-to-day fatigue – which can increase your risk of accidents and injuries and make it harder to concentrate, stay productive or manage your emotions at home and work – chronic lack of sleep can lead to serious health problems. It can also worsen existing conditions, like cardiovascular disease, diabetes, obesity and depression.

Who gets sleep apnea?

While obstructive sleep apnea is most commonly diagnosed in men who are older and overweight, the disorder can affect individuals of any age, gender or background – including children. Research shows that having a close family member with the sleep disorder increases the likelihood of developing the condition. This may be influenced by inherited physical traits such as body shape and fat distribution, facial and neck structure, and sleep patterns.

Similarly, genetics can play a role in the risk of developing medical conditions often linked to sleep apnea, including cardiovascular diseases, diabetes, obesity and depression.

Here’s a closer look at those conditions.

Cardiovascular diseases

One of the most important organs in your body is your heart. It’s the pump that helps push your blood through your body, carrying oxygen and nutrients your cells need to work. It also helps push your blood through to your other vital organs (such as your brain, lungs, kidneys and liver), so they can perform their duties. Your heart also controls your blood pressure and heart rate.

The human body works like an efficient recycling plant. Your arteries carry blood with oxygen out of your heart to deliver to other parts of your body, while your veins bring the blood back to the heart for more oxygen.

Oxygen helps fuel your heart.

Because obstructive sleep apnea makes it harder to breathe, it makes it harder for your heart to get the oxygen it needs to function and limits the supply of oxygen to pass around.

Over time, this lack of oxygen can strain your heart and the rest of your body, which may worsen or lead to a range of serious cardiovascular conditions, including:

• High blood pressure (hypertension) – To make up for the limited oxygen, your heart may begin beating faster and harder. This strains your heart, but also puts too much pressure on your arteries. Over time, they may begin to weaken or even tear. When they do, your heart works even harder. Eventually, this can lead to many things, including a heart attack or stroke.

• Heart attack – Without enough oxygen, part of your heart can get damaged or even die. Considering your heart is the “engine” that keeps your body going, this damage can lead to serious health problems – and can be fatal.

• Heart failure – The repeated oxygen shortages sleep apnea causes can make your heart struggle to keep up with your body’s pumping needs. Over time, this can lead to heart failure, which causes fatigue, shortness of breath and swelling in your legs or feet. Left untreated, these symptoms can worsen and may result in serious, even fatal, complications.

• Stroke – This can happen if your brain isn’t getting the blood and oxygen it needs, and cause a variety of symptoms, including speech, vision or mobility losses.

Cardiovascular diseases are treatable. It’s important to consult a medical provider for diagnosis and a treatment plan tailored to you – and to follow that plan closely.

Type 2 diabetes

Insulin is a hormone your pancreas produces to help your body move sugar (glucose) from food into your cells, where it’s used for energy. If you have type 2 diabetes, your pancreas either becomes resistant to insulin or doesn’t make enough of it. This makes it harder for your body to regulate blood sugar and use glucose effectively.

Over time, this can cause too much sugar to build up in your bloodstream, which can damage your heart, nerves, eyes, kidneys (your body’s filter) and other vital organs. Because of this, having type 2 diabetes significantly increases your risk for a variety of serious health problems, including cardiovascular disease, vision loss and kidney disease.

Sleep apnea and type 2 diabetes commonly occur together – and each makes the other harder to manage.

Chronic poor sleep changes how your hormones work, including your body’s ability to turn calories from sugar into energy. It also makes your body produce more of the hormone ghrelin (which makes you feel hungry) and less of the hormone leptin (which helps you feel full). As a result, many people with OSA tend to eat more than they need to, creating a circular cause and effect, which also can lead to obesity. (See next section below.)

While there’s no cure for type 2 diabetes, it can be managed with lifestyle changes and medications. Depending on which came first – your type 2 diabetes or sleep apnea – managing one can help prevent the other. And if you have both, it’s very important to treat them at the same time.

Obesity

Health care providers often use a body mass index (BMI) – calculated as weight divided by the square of your height – as a benchmark for healthy weight. While it’s not a foolproof method, it can still help gauge whether your weight may pose a health risk. (For example, a bodybuilder might exceed the “healthy” BMI range despite having low body fat.) A BMI over 25 is generally considered overweight and over 30 is considered obese. If you have questions or are concerned about your BMI, it is best to speak with your provider.

Similar to type 2 diabetes, obesity and obstructive sleep apnea can be a cause and effect.

Obesity is associated with many health risks, including obstructive sleep apnea, cancer, hypertension and depression.

As noted above, poor sleep also disrupts your appetite and your hormones. It also slows your metabolism and causes fatigue, making it harder to burn calories, stay active or feel motivated. Over time, this combination can lead to weight gain.

At the same time, when you carry excess weight, fat can build up around your neck and chest, making it harder to breathe by narrowing your airway. This restriction can reduce lung capacity and make your upper airway more likely to collapse, raising your risk of obstructive sleep apnea, even with modest weight gain.

(For a deeper dive, read How weight affects obstructive sleep apnea.)

Depression

People who don’t get enough sleep – even one night’s worth – tend to feel drained, sad and cranky. But when those nights keep adding up, the chronic fatigue can throw off the balance of brain chemicals like serotonin and dopamine that help regulate mood and stress. Over time, this can lead to clinical depression, a serious mental health disorder.

While everyone feels down at times, depression makes people feel sad and hopeless. They tend to lose interest in people and activities they used to enjoy. It also can affect how they think and behave, often leading to low self-worth and irritability. Depression is also a significant risk factor for suicide, one of the leading causes of death worldwide.

The good news is depression is treatable. So are cardio vascular diseases, diabetes and obesity.

Talk to your doctor

If you are concerned you or someone you care about may have obstructive sleep apnea or another serious condition, it’s important to consult with a health care provider or mental health professional. Based on your symptoms, age, overall health, insurance coverage and lifestyle factors, they can make a diagnosis and recommend a treatment plan.

Rest assured, many people find a treatment for sleep apnea that fits their lifestyle, helping them manage their condition and enjoy fulfilling lives.

Sources

American Heart Association, Obstructive Sleep Apnea and Cardiovascular Disease: A Scientific Statement From the American Heart Association. June 21, 2021.

American Heart Association, Sleep Apnea and Heart Health. June 26, 2023.

American Heart Association, What is High Blood Pressure? May 23, 2024.

American Medical Association, What doctors wish patients knew about sleep apnea. April 1, 2022.

American Psychiatric Association, What Is Depression? April 2024.

Better Health Channel, Heart explained. February 25, 2022.

Centers for Disease Control and Prevention, About Body Mass Index (BMI). May 20, 2024.

Centers for Disease Control and Prevention, Type 2 Diabetes | Diabetes. May 15, 2024.

Cleveland Clinic, Heart: Anatomy & Function. January 26, 2024.

Cleveland Clinic, High Blood Pressure: Symptoms & Causes. May 5, 2023.

Cleveland Clinic, Sleep Apnea: What It Is, Causes, Symptoms & Treatment. January 15, 2025.

European Respiratory Society, Obstructive sleep apnoea and long-term risk of incident diabetes in the middle-aged and older general population.

Johns Hopkins Medicine, Obstructive Sleep Apnea. Accessed July 3, 2025.

Loyola Medicine, The Silent Threat of Sleep Apnea: Why Ignoring Symptoms Can Be Dangerous. December 19, 2024.

Mayo Clinic, Type 2 diabetes - Symptoms and causes. February 27, 2025.

National Sleep Foundation, Living with Obstructive Sleep Apnea. March 5, 2025.

PMC, Journal of Diabetes Investigation, Sleep apnea and type 2 diabetes. April 14, 2018.

PMC, Obstructive Sleep Apnea and Diabetes: A State of the Art Review. May 17, 2017.

Sleep Foundation, How Weight Affects Sleep Apnea. April 30, 2024.

Sleep Foundation, Is Sleep Apnea Genetic? December 22, 2023.

Sleep Foundation, Mental Health and Sleep. March 26, 2024.

Sleep Foundation, Obstructive Sleep Apnea: Symptoms, Causes, and Treatments. Updated April 16, 2024.

World Health Organization, Depression. Accessed July 7, 2025.

World Health Organization, Obesity. Accessed July 7, 2024.

World Health Organization, Suicide. Accessed July 7, 2025.