What Is Central Sleep Apnea and How It Differs from Obstructive Sleep Apnea

Central sleep apnea (CSA) is a condition that affects breathing during sleep, but it differs significantly from the more commonly known obstructive sleep apnea (OSA). While both involve pauses in breathing, the causes and treatments vary between the two. Central sleep apnea is often associated with how the brain communicates with the body’s respiratory system rather than physical blockages in the airway.

How Central Sleep Apnea Occurs

In central sleep apnea, the brain fails to send the correct signals to the muscles that control breathing. As a result, there are repeated periods during sleep when breathing stops for 10 seconds or more. These interruptions can reduce oxygen levels in the blood and disrupt the natural sleep cycle, leading to excessive daytime sleepiness and other health issues.

Unlike obstructive sleep apnea, which is typically caused by the collapse of the soft tissues in the throat, central sleep apnea is a neurological issue. The airway remains open, but the body simply does not make an effort to breathe.

Types of Central Sleep Apnea

Central sleep apnea can be classified into several different types, depending on the underlying cause:

• Idiopathic (Primary) CSA: No identifiable cause is found. It may occur sporadically and without other medical conditions.
• Cheyne-Stokes Breathing: Often seen in individuals with heart failure or stroke. Breathing follows a pattern of gradual increases and decreases in airflow followed by pauses.
• CSA due to medical conditions: Can be linked to conditions such as brainstem injury, Parkinson’s disease, or kidney failure.
• CSA due to medications: Opioids and other drugs that affect the brain’s respiratory centers can contribute to central apnea events.
• Treatment-emergent CSA: Some individuals being treated for obstructive sleep apnea with CPAP therapy may develop central events after starting treatment.

Common Symptoms

Many symptoms of central sleep apnea overlap with those of obstructive sleep apnea, but there are some unique features to look out for:

• Frequent nighttime awakenings
• Insomnia or fragmented sleep
• Morning headaches
• Excessive daytime sleepiness
• Shortness of breath that wakes you up at night
• Difficulty concentrating or memory issues

Because the pauses in breathing aren’t typically associated with snoring or physical airway obstruction, CSA may be harder to detect without a sleep study.

Diagnosing Central Sleep Apnea

Diagnosing central sleep apnea typically involves an overnight sleep study known as a polysomnogram. This test measures various body functions during sleep, including brain activity, eye movements, heart rate, oxygen levels, and breathing effort.

In cases of CSA, the sleep study will show a lack of respiratory effort during apnea episodes, distinguishing it from obstructive events where there is visible effort but the airway is blocked.

Sometimes, additional testing such as an echocardiogram or neurological imaging may be needed to uncover underlying medical conditions contributing to the apnea.

Treatment Options for Central Sleep Apnea

Treatment for central sleep apnea varies depending on the underlying cause and severity of the condition. Some of the most common approaches include:

• Adaptive Servo-Ventilation (ASV): A specialized type of positive airway pressure device that adjusts pressure based on detected breathing patterns. ASV is commonly used in CSA related to Cheyne-Stokes respiration.
• Bilevel Positive Airway Pressure (BiPAP): Provides two different pressure settings for inhalation and exhalation, supporting more natural breathing patterns.
• Supplemental Oxygen: In some cases, adding oxygen during sleep can help maintain safe oxygen levels and reduce apneas.
• Medication adjustment: Reducing or stopping medications such as opioids may help reduce central apnea events when they are a contributing factor.
• Treating underlying conditions: Addressing conditions like heart failure, brain injury, or kidney disease may improve or resolve central sleep apnea.

Lifestyle Adjustments That May Help

Although central sleep apnea is often linked to neurological or medical causes, some general health practices can support better sleep and respiratory function:

• Sleep on your side: Sleeping in a supine position (on your back) can worsen apnea in some people. Side sleeping may help in milder cases.
• Limit alcohol intake: Alcohol can depress the central nervous system and exacerbate breathing irregularities.
• Avoid sedatives: Medications that slow brain activity, including sleeping pills and anti-anxiety drugs, may worsen CSA symptoms.
• Maintain a healthy weight: While weight is more strongly linked to obstructive apnea, achieving a healthy body composition can still be beneficial.

Because central sleep apnea is often related to complex medical conditions, close collaboration with a healthcare provider or sleep specialist is important for proper diagnosis and management.