While we sleep, it’s easy to assume that we are breathing the entire time. After all, throughout our waking lives, we breathe without thinking about it. Idiopathic central sleep apnea syndrome or Idiopathic CSA often stop breathing five or more times per hour of sleep. What makes idiopathic CSA different than other forms of sleep apnea is that the cause of it is unknown to doctors. A person is usually diagnosed with idiopathic central sleep apnea when all other causes are ruled out.
Known Causes of Central Sleep Apnea Syndrome (CSAS)
CSAS is usually linked to underlying health conditions. Treatment of such underlying conditions can help improve idiopathic CSAS symptoms. Here are a few conditions linked to CSAS.
- Renal failure
- Heart failure
- Brainstem lesions
- Malformations such as Arnold Chiari malformation
- Narcotic use
- Endocrine disorders such as hypothyroidism
Types of Central Sleep Apnea
CSA can be a natural occurrence during sleep as the body transitions into sleep or while being aroused from sleep.
According to the International Classification of Sleep Disorders (ICSD), there are several types of CSA disorders. Some conditions are well defined, while others are still being researched to understand their mechanisms better. Here are a few of the different types of apnea disorders.
Idiopathic CSA is a rare disorder. At this time, researchers are still unclear regarding all the factors that can cause this condition. For this reason, Idiopathic CSA is usually diagnosed after doctors exclude other forms of sleep apnea. This condition is more commonly found in older males.
As mentioned early, CSA can be caused by drug or substance abuse. Research has found this condition to be linked to roughly 30 percent of people using narcotics.
Cheyne-Stokes Respiration (CRS)
CRS represents a pattern in a person’s breathing defined by changes in crescendo-decrescendo tidal air volume cycles. A form of central sleep apnea usually follows these changes. CRS cycles can take 45 seconds or longer to complete. It takes at least ten recorded cycles of apnea, hypopnea, hyperpnea, hypopnea, and apnea before diagnosing CRS.
High Altitude Periodic Breathing:
High altitude periodic breathing consists of episodes of central apnea. Or, a person can experience hypopnea cycling with episodes of hyperpnea as a person sleeps while they ascend to higher altitudes. Anyone can experience this type of breathing if they are at altitudes higher than 4.7 miles above the Earth.
What Doctors Look for
Common symptoms of CSA can be similar to symptoms linked to other breathing disorders while sleeping. These symptoms can include sporadic sleep interrupted by frequent awakenings, fatigue, nonrestorative sleep, snoring, sleepiness, sleep maintenance or sleep onset insomnia, and problems concentrating. However, some patients are asymptomatic.
Obstructive Sleep Apnea or Central Sleep Syndrome
There are several things doctors look for when diagnosing someone who either has Obstructive Sleep Apnea Syndrome or Central Sleep Syndrome. These two sleep disorders often have similar symptoms. However, some factors make them distinct.
Obstructive sleep apnea is usually caused by the collapse of a person’s upper airway, stopping or decreasing airflow despite how hard their body tries to compensate using extra respiratory effort.
However, CSA and hypopnea happen when a person stops breathing, or experiences reduced respiratory drive and effort, which leads to a reduction in airflow in their airway.
Doctors can differentiate between these two conditions by having their patients undergo an overnight polysomnogram. During this process, they record airflow, abdominal, and chest respiratory efforts.
Central Sleep Apnea: Who’s Most At Risk?
There are several risk factors doctors consider when diagnosing CSA. These include:
- Experiencing breathing issues while ascending to high altitudes.
- Patients who’ve had congestive heart failure (25 to 40 percent of patients with this condition develop sleep breathing disorders).
- Age (Older individuals are more likely to experience CSA)
- Other medical issues such as renal failure, hypothyroidism, neurogenerative disorders, and Arnold Chiari malformation.
- People who’ve had a stroke (10 to 20 percent of stroke patients report CSA symptoms)
- Drug users (30 percent of narcotics users experience CSA)
- Gender: Research found that hormones found in men make them more susceptible to CSA than women.
When it comes to treating CSA, the main goal is to return a patient’s breathing to normal during sleep or otherwise improve their symptoms. However, except for CSA/CSR associated with congestive heart failure (CHF), there isn’t much data regarding CSA syndromes. Without this information, doctors focus more on improving their patient’s symptoms.
Doctors may use continuous positive airway pressure therapy (CPAP) to assist their patient’s breathing as they sleep. However, if this therapy isn’t effective, doctors may treat CSA patients with supplemental oxygen.
Another treatment that has shown promise when used on patients who experience CSA due to congestive heart failure is a device called adaptive servoventilation (ASV). This device studies a patient’s breathing pattern and tries to stabilize their breathing by changing the pressure and ventilatory rate support it gives.
CSA is a condition that should be taken very seriously. People who do not get enough quality sleep are often more susceptible to more serious medical issues down the road, such as heart problems. Please talk to your doctor if you’re experiencing any of the above-mentioned symptoms.