Mild Sleep Apnea

Key Takeaways

• Mild sleep apnea refers to sleep apnea with an AHI of 5 to 15 breathing events per hour.
• While not as serious as moderate or severe sleep apnea, mild sleep apnea can still affect quality of life and may contribute to high blood pressure. Plus, when left untreated, symptoms — and health risks — can worsen.
• Treatments for mild sleep apnea include CPAP and EPAP therapy, oral appliances, and lifestyle changes.

What Is Mild Sleep Apnea?

The severity of someone’s sleep apnea is defined by the average number of breathing events that occur per hour of sleep, often measured by the apnea-hypopnea index (AHI). A person with mild sleep apnea experiences an average of five to 15 breathing events per hour. Moderate and severe sleep apnea are characterized by a higher number of breathing events.

• Mild sleep apnea: 5 to 15
• Moderate sleep apnea: 15 to 30
• Severe sleep apnea: 30+

The score is calculated by adding up all the breathing events during the entire sleep period, then dividing that number by the number of hours slept. The definition of a “breathing event” can change depending on whether you count just apneas, or also hypopneas or respiratory effort related arousals (RERAs). 

• Apnea: Breathing completely stops for 10 to 60 seconds.
• Hypopnea: Breathing drastically slows but doesn’t stop completely.
• Respiratory-effort related arousal (RERA): This period of reduced breathing may not register as a hypopnea but lasts longer and affects blood oxygen levels.

When a test includes RERAs, it’s termed the respiratory disturbance index (RDI), which is more sensitive to mild cases of sleep apnea. 

Mild Sleep Apnea Symptoms

Symptoms of mild sleep apnea are similar to symptoms of moderate to severe sleep apnea, but they may be less noticeable:

• Loud, frequent snoring
• Waking up gasping or choking
• Noticeable pauses in breathing
• Daytime sleepiness or fatigue
• Morning headaches

Someone with mild sleep apnea may experience daytime sleepiness only during monotonous activities. People may also get used to being sleepy, to the extent that they don’t realize it’s not normal to feel that way.

Causes of Mild Sleep Apnea

Mild sleep apnea has the same causes as moderate or severe sleep apnea, but it’s important to differentiate between the two types of sleep apnea: obstructive sleep apnea and central sleep apnea.

Central sleep apnea (CSA) results from a communication breakdown between the brain and the muscles that control breathing, and it’s usually caused by an underlying medical condition, such as heart failure or stroke. 

In obstructive sleep apnea, lapses in breathing are due to physical blockage of the airway. Some potential factors for OSA include:

• Obesity
• Neck circumference larger than 16 inches
• Large tonsils
• Anatomical features that narrow the airway or nasal passages
• Older age and menopause

Drinking alcohol before bed, taking sedative medications, and sleeping on your back may trigger breathing events, as these all relax the muscles and tissues in the airway.

Diagnosing Mild Sleep Apnea

The most reliable way to diagnose mild sleep apnea is with an in-lab sleep study, which tracks breathing, blood oxygen levels, brain activity, and other key metrics overnight. However, at-home sleep apnea tests — such as Sleep Doctor’s at-home sleep study — can be a convenient first step. These tests monitor breathing and oxygen levels from the comfort of your own bed and can help identify clear cases of obstructive sleep apnea.

To obtain a formal diagnosis of sleep apnea, a person must have at least 15 breathing events per hour of sleep, or at least five events per hour plus one or more symptoms:

• Insomnia, fatigue, unrefreshing sleep, or daytime sleepiness
• Waking up throughout the night gasping or choking, or holding their breath
• Pauses in breathing or snoring observed by a bed partner
• Diagnosis of a related condition such as high blood pressure, a mood disorder, or type 2 diabetes

Although mild sleep apnea is currently defined by the number of breathing events per hour, some experts argue that this doesn’t give the full picture. For example, when considering the risk of certain heart problems, there’s evidence to suggest that nighttime blood oxygen levels may be more significant than the number of breathing events. 

Additionally, having a higher percentage of events during rapid eye movement (REM) sleep may be worse for health. It’s common for women with sleep apnea to have more events in REM sleep and be diagnosed with milder forms of sleep apnea. Similarly, someone with long periods of shallow breathing may be diagnosed with mild sleep apnea, even if these periods last much longer than a typical apnea.

Experts say it might be more useful to consider multiple factors, such as effects on sleep, nervous system activity, and changes in blood pressure, when determining whether sleep apnea requires treatment.

Mild Sleep Apnea Treatment

Mild sleep apnea is most effectively treated with CPAP therapy or an oral appliance. If you’re diagnosed through Sleep Doctor’s at-home sleep test, a sleep care advocate can walk you through all your treatment options and help you choose the approach that best fits your needs and lifestyle.

• Continuous positive airway pressure (CPAP) therapy: CPAP therapy keeps the airway open during sleep by blowing a gentle stream of pressurized air into the nose and/or the mouth. This is the most commonly prescribed therapy, and it works well for mild, moderate, and severe sleep apnea.
• Expiratory positive airway pressure (EPAP) therapy: EPAP therapy involves a small, mask-free device placed over the nostrils that creates resistance when you exhale, helping keep the airway open and reduce breathing interruptions during sleep.
• Oral appliances: Oral appliances keep the airway open by pulling the lower jaw or the tongue forward. These devices are effective for mild to moderate OSA but less effective for severe OSA.
• Myofunctional therapy: Therapy exercises for the muscles in the upper airway might help improve symptoms of mild OSA, especially when combined with a tongue stimulator, but more research is needed.
• Lifestyle changes: Working toward a healthy weight, getting regular exercise, and avoiding alcohol and sedatives can all help with sleep apnea.
• Treating nasal congestion: Clearing up nasal congestion with medicine or nasal sprays can help promote mouth breathing, which in turn improves OSA.
• Practicing good sleep hygiene: Sleeping soundly tends to lower the amount of breathing interruptions during sleep, and this may be particularly true for people with mild OSA. Also, switching from back sleeping to side sleeping can also be helpful.

People with central sleep apnea should also treat the medical condition that’s causing the apnea, such as heart failure.

Note: You shouldn’t use mouth tape unless you’ve already talked to your doctor, as there isn’t enough evidence on whether this effectively treats sleep apnea and, in fact, may be dangerous for people with untreated sleep apnea.

Frequently Asked Questions

Is mild sleep apnea dangerous?

Mild sleep apnea has fewer health consequences than moderate and severe sleep apnea, but it still carries some risks. In particular, mild sleep apnea appears to contribute to high blood pressure (including systemic arterial hypertension) and possibly atrial fibrillation. For some people, mild sleep apnea also causes daytime sleepiness, which may be dangerous in traffic or sensitive work situations.

Does mild sleep apnea need to be treated?

Mild OSA should be treated if it’s causing symptoms or if you have a co-existing disorder like high blood pressure. Experts also recommend treating mild OSA if you have a job that requires being alert for safety reasons, as is the case for pilots, air traffic controllers, bus and truck drivers, locomotive engineers, or doctors and nurses. Sleep apnea treatments have been shown to have positive effects on blood pressure and quality of life. 

Can mild sleep apnea go away?

Sleep apnea is generally considered a lifelong disorder, but when it’s mild, it may go away, depending on the underlying cause. For example, mild sleep apnea due to obesity may go away if you lose weight. Some people only get sleep apnea symptoms on nights when they drink alcohol or if they’re very tired.

Mild sleep apnea won’t necessarily progress to moderate or severe sleep apnea, but it does often worsen as you age or if you gain weight, especially if left untreated.

Do you need a CPAP for mild sleep apnea?

CPAP therapy for mild sleep apnea is effective, but it’s not the only treatment option. Mild sleep apnea also responds well to special mouthguards that hold the mouth in a better position for breathing. 

Depending on the cause of your sleep apnea, you may also find your symptoms improve with lifestyle changes like losing weight, treating seasonal allergies, sleeping on your side, or cutting out alcohol before bed.

Can mild sleep apnea cause high blood pressure?

Although it’s not as strongly implicated in most health markers, mild OSA does increase the risk of high blood pressure, especially for younger people. This holds true even if you don’t have symptoms like daytime tiredness.

Does mild sleep apnea make you tired?

Some people experience unrefreshing sleep and daytime sleepiness due to mild sleep apnea, while others have no symptoms and might not even notice they have sleep apnea at all. It’s fairly common for people not to realize they have daytime sleepiness until they stop drinking alcohol, lose weight, or start sleep apnea treatment and suddenly find they have more energy.

How common is mild sleep apnea?

It’s estimated that almost one billion middle-aged adults worldwide have OSA, and approximately half of these cases are mild. However, many of these people haven’t been diagnosed and might not be aware they have sleep apnea. OSA diagnoses are rising, partly due to better diagnostic methods but also because of rising obesity rates.