Sleep apnea is a disorder that involves pauses in breathing during sleep. Three main types exist: obstructive, central, and complex. Each is defined and treated based on its underlying cause.

Apneas are involuntary pauses in your breathing. When they occur during sleep, they’re referred to as sleep apneas. If these pauses become regular, persistent patterns that negatively affect your health, you may be living with a sleep apnea disorder.

Several types of sleep apnea disorders exist, each with different underlying causes but similar symptoms. All types of sleep apnea can reduce oxygen levels in your bloodstream while you sleep, leading to low quality sleep and challenges like excessive daytime sleepiness (EDS).

Sleep apnea is common. Experts believe as many as 30 million people in the United States live with this type of sleep disorder — but of those, only around 6 million have received a formal diagnosis.

Since it occurs when you’re not awake, sleep apnea can be difficult to detect, especially if you live alone.

Obstructive sleep apnea (OSA) is the most common type of sleep apnea. It occurs when the muscles of your upper airway at the throat relax or collapse inward and create a temporary blockage.

Many factors can contribute to closure of the airway in OSA, including:

  • obesity
  • large neck circumference
  • smoking
  • alcohol use
  • structural irregularities in the face or neck
  • older age
  • pregnancy
  • sleeping position
  • other medical conditions, like congestive heart failure or diabetes

Common symptoms

If you’re experiencing OSA at night, common symptoms include:

  • gasping for air during sleep
  • choking during sleep
  • frequent, loud snoring during sleep
  • frequent nighttime waking
  • morning headache
  • EDS
  • difficulty concentrating
  • dry mouth
  • sexual dysfunction or libido loss

Your partner or housemate may report noticing that your breathing stops and restarts when you sleep.

Treatment options

After making an OSA diagnosis, a doctor will recommend management strategies that focus on keeping your airway open.

A treatment plan for OSA may include:

  • positive airway pressure (PAP) therapy via a machine that delivers a continuous flow of air into your airway while you sleep
  • a custom-made mouthpiece to reposition your jaw or tongue
  • sleep position education (encouraging side sleeping)
  • lifestyle changes, such as smoking cessation, weight management, and exercise
  • surgery to remove or reposition tissues in the airway to prevent collapse

Central sleep apnea (CSA) occurs when your brain doesn’t correctly signal your muscles to breathe. This lack of effort creates a pause in your respirations (inhales and exhales) at night. Many people with CSA also experience a closure of the upper airway during moments of apnea in CSA.

CSA is closely associated with other medical conditions that promote central breathing instability while you sleep, such as:

Common symptoms

If you’re experiencing CSA, you may notice symptoms such as:

  • frequent waking at night
  • insomnia
  • EDS
  • morning headache
  • difficulty concentrating
  • other people noticing your breathing stopping and restarting while you sleep

Unlike OSA, CSA doesn’t typically cause frequent snoring.

Treatment options

The overall treatment goals for CSA are the same as other types of sleep apnea.

Your CSA management plan may include:

  • PAP therapy
  • nighttime oxygen supplementation
  • phrenic nerve stimulation, which refers to using a device to stimulate the phrenic nerve that controls your diaphragm and regulates breathing
  • medications to stimulate breathing, such as acetazolamide
  • management of underlying medical conditions contributing to CSA

Complex sleep apnea, also known as mixed sleep apnea or treatment-emergent central sleep apnea, refers to OSA and CSA that happen at the same time.

Central sleep apnea typically develops when PAP therapy for OSA alters breathing patterns, changes the mechanics of your respiratory system, or causes confusion in your brain’s breathing signals.

It may also develop if you’re experiencing OSA and live with a condition that makes CSA more likely, such as heart failure.

Symptoms of complex sleep apnea can include both those of OSA and CSA.

Complex sleep apnea also combines the treatment options for OSA and CSA.

Sleep apnea can be difficult to detect on your own, and symptoms like EDS are often attributed to other factors in life, like stress.

Any time you notice a persistent pattern developing in your health (like feeling tired all day, nearly every day), or if another person tells you they’ve noticed your breathing stop and restart at night, it may be time to talk with a doctor.

Even persistent, loud snoring can be enough of a reason to discuss sleep apnea screening.

If you’re not certain whether sleep apnea should be a concern, tuning into your sleep patterns and your daily energy levels is one of the best ways to gain insight.

Keeping a journal of symptoms like gasping, choking, frequent waking, and EDS can clue you into the likelihood that sleep apnea may be occurring at night.

What are the three types of sleep apnea?

The three types of sleep apnea are obstructive, central, and complex.

What is the most severe form of sleep apnea?

The most severe form of sleep apnea is often regarded as central sleep apnea, as it can have a higher risk of death.

There are three primary types of sleep apnea: obstructive, central, and complex. While they can all feature similar symptoms like EDS, different underlying causes set them apart.

If you receive a diagnosis of sleep apnea, a doctor will discuss a variety of management strategies with you, including PAP therapy, lifestyle changes, and medications.