Medically reviewed by
Dacelin St Martin, MD
Triple board-certified in Sleep Medicine,
Internal Medicine, and Pediatrics.
What is CSA | Epidemiology | Symptoms | Risk Factors | Causes & Types | Complications | Diagnosis | Treatment
According to research, there are over 80 types of sleep disorders, with sleep apnea (SA) being one of the most common. The disorder is comprised of two types, namely central sleep apnea (CSA) and obstructive sleep apnea (OSA).
There may be some confusion in distinguishing OSA from CSA; although they can have similar symptoms, they each have different causes.
If you have one of the CSAs and are not correctly diagnosed and given the right treatment, you may be susceptible to developing chronic diseases, like obesity, diabetes, hypertension, or heart disease.
This article will present vital facts that will help you understand, diagnose, and treat your CSA. Also, we include a section to guide you in differentiating CSA from OSA.
What is CSA?
CSA is a sleep disorder that is characterized by a repetitive cessation and diminished airflow and ventilation despite the respiratory effort.
With CSA, you may experience a severe shortage or a complete lack of oxygen, which causes you to intermittently wake up throughout the course of the night. CSA happens because of a problem with the brain’s signaling.
Put another way, if you have CSA, your brain “forgets” to tell the muscles responsible for breathing to breathe. It’s like a communication breakdown of sorts.
CSA can be related to two breathing deficiencies: when your breathing removes more carbon dioxide than your body can make it’s called hyperventilation, while hypoventilation is when carbon dioxide levels in your body are too high.
Hyperventilation-related CSA is more common and can be the result of Cheyne-Stokes respiration, heart failure, or high altitudes.
Hypoventilation-related CSA is less common and can be the result of conditions, such as neuromuscular disease, abnormalities regarding pulmonary function, or central nervous system suppressing drugs, like opioids.
CSA is far less common than OSA. A community-based study of 5804 subjects, over the age of 40, found that 0.9% of the subjects had CSA.
More than half of the symptoms of CSA are the same as OSA, including:
- Abnormal breathing or moments of paused breathing during sleep
- Sudden awakenings followed by feelings of breathlessness
- Breathlessness is relieved when you sit up
- Restless sleep or inability to stay asleep (insomnia)
- Early morning headaches
- Daytime sleepiness (hypersomnia)
- Chronic fatigue
- Mood changes
- Difficulty with concentration
- Chest pains or discomfort at night
- Inability to exercise as much as you usually would
If a neurological disease causes your CSA, you may also have the following symptoms:
- Voice changes
- Swallowing difficulties
- General body weakness and numbness
How to Differentiate CSA from OSA
If you experience any or all of the following symptoms, you may have OSA. If they’re not present, you may be battling with CSA:
- Snoring: Although snoring is present in CSA and OSA, it is more prominent with OSA than CSA
- Paradoxical breathing: Chest wall and abdominal wall contract instead of expanding when breathing in and expand instead of contracting when exhaling
- Flattening of the nasal airway pressure flow or rise in PAP flow signal
Age: CSA is common among adults over the age of 65
Sex: Males have a higher risk of having CSA than women
Stroke: CSA, most times, appears after a stroke
Brain tumor: Any problem with the brain could impair its ability to control breathing adequately
Heart failure: People with congestive heart failure or irregular heartbeats (Cheyne–Stokes respiration) are more likely to have the disorder
Medications: Chronic users of opioids and patients undergoing methadone maintenance therapy have a greater chance of having CSA
High Altitude: High altitude decreases the amount of oxygen in the blood. So sleeping at that height, when your body is yet to acclimatize, could cause symptoms of CSA
Causes and Types
CSA can be caused by anything that affects your brain’s ability to transmit signals to regulate your breathing. Moreover, these causes vary with the kind of CSA you have. The types and causes of CSA include:
- Idiopathic or primary CSA – A type of CSA with no known cause or disease
- Cheyne-Stokes breathing CSA – Typically associated with stroke, congestive heart failure, or kidney failure
- Drug-induced CSA – Commonly caused by chronic use of opiates, morphine, codeine, or oxycodone
- High altitude CSA – This often appears at elevations of 3000 or 4000 feet and higher
- Medical condition-induced CSA – As the name implies, this kind of central sleep apnea can be triggered by several medical conditions such as stroke, heart failure, and end-stage kidney disease
- Treatment-emergent CSA – This may happen when people with OSA are being treated with CPAP (continuous positive airway pressure) 
CSA and OSA can affect your concentration and make you extremely tired, thus, increasing your risk of home, work, or road-related accidents. Besides this, the two forms of sleep apnea can also lead to serious health complications, including:
A comprehensive sleep study using polysomnography can diagnose why your breathing is repeatedly pausing, which can be due to:
- Airway blockage (OSA) or
- Uneven breathing signals sent by your brain (CSA)
In polysomnography testing, a healthcare professional connects you to equipment at the testing center. During sleep, the device keeps track of your breathing patterns, blood oxygen levels, movements of your arms and legs, and your brain, heart, and lung activities.
Your sleep doctor or specialist evaluates your condition based on the readings collected and the symptoms you’re experiencing.
When assessing symptoms, like daytime sleepiness, it’s imperative to consider alternate sleep disorders. This process may involve the use of a polysomnography test. A differential diagnosis may include:
- Obstructive Sleep Apnea
- Periodic Limb Movements of Sleep
- Shift Work Sleep Disorder
- Respiratory Disease 
Generally, CSA is best treated by diagnosing the cause. In some situations, when the “causative disease” is treated, the severity of CSA reduces, or the disorder goes away.
At other times, you may have to be treated by a breathing specialist and another medical specialist for the primary disease simultaneously.
For example, someone with kidney problems might go back and forth between a nephrologist and his or her sleep doctor. When CSA is caused by high altitudes, returning to lower elevations will eliminate the symptoms.
When CSA is hypoventilation-related, reducing the dosage or eliminating medications that are causing disordered breathing, like opioids, is an important first step.
When CSA is hyperventilation-related, especially for those with heart failure, treatment might include the use of a continuous positive airway pressure machine (CPAP).
CPAP can reduce the number of apneas and help to prevent the narrowing or closing of pharyngeal airways. This effect is achieved by increasing negative airway pressure, allowing for breathing to resume.
Supplemental oxygen can be used in addition to CPAP, or alone, especially for patients with hyperventilation-related CSA.
Medications can also be used to stimulate breathing. An effective medication used for CSA is acetazolamide (Diamox); however, patients must be monitored as a pharmacological approach can have harmful side effects.
Talk to your doctor about avoiding or reducing the dosage of drugs and substances that suppress your brain’s ability to control breathing.
If any of these drugs are part of your prescription drugs, consult your doctor before stopping them. Lastly, take note of your symptoms and sleep patterns to share with your doctor.
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