Sleep apnea is a common and dangerous respiration disorder in which breathing is interrupted by recurrent attacks during sleep. If left untreated, it can play a role in the development of some important diseases such as Type 2 diabetes, stroke or heart attack.
The prevalence of this disorder is estimated to be 5 – 10% in population. In order to make a definitive diagnosis, breathing must be interrupted for at least 10 seconds during sleep.
Types of sleep apnea
This health problem is divided into 3 subtypes:
1- Obstructive Type
The obstructive type is characterized by episodes of low oxygen levels and sleep interruption caused by complete or partial loss of airway function. This disorder results in a marked reduction in the quality of sleep. These basic symptoms are often accompanied by other complaints such as loud snoring and daytime sleepiness. It is the most common type of apnea in the society.
2- Central Type
The central type is a form of apnea that occurs when the centers in the brain fail to send appropriate signals to the muscles that control breathing. The person’s oxygen carbon dioxide balance is adversely affected due to repeated respiratory arrest during sleep. Unlike the obstructive type, respiratory functions cannot be maintained in central apnea and therefore airflow is interrupted. Patient complaints are almost the same as in the obstructive type. If the underlying cause is Parkinson’s disease or a similar neurological disorder, additional symptoms such as difficulty swallowing, decreased speech ability, changes in voice tone and general weakness may also be seen.
3- Mixed Type (Complex Type)
In mixed type, both obstructive and central types are seen together.
What are the symptoms of sleep apnea?
- Loud snoring (mostly in obstructive type)
- Attacks of breathing interruptions witnessed by household members
- Sudden wakes during sleep (more common in central type)
- Dry mouth or sore throat when you wake up in the morning
- Headaches in the morning
- Depressed mood
- Attention problems
How is sleep apnea diagnosed?
To diagnose the disease, your doctor first questions your complaints in detail. Then he/she performs a general examination and ear, nose and throat evaluation. The upper airways are examined by a flexible cannula with a camera at the end called flexible bronchoscopy. Radiologic examinations such as MRI and CT can be used to visualize the airways and examine stenosis.
If necessary, the patient is admitted to a sleep research center for a more detailed evaluation. In order to make a certain diagnosis, a sleep analysis test called polysomnography is essential. This test measures the severity and frequency of respiratory arrests. In addition, it can be designed with additional tests to check heart rhythm, blood oxygen percentage and the severity of snoring. Polysomnography evaluates the activity of many organ systems:
- Brain waves with electroencephalography (EEG)
- Changes in eye movements with electrooculography (EOM)
- Muscular stress and activity by electromyography (EMG)
- Heart functions and performance with electrocardiography (ECG)
- Oxygen level in the bloodstream with pulse oximetry
How is sleep apnea treated?
Treatment options include lifestyle changes, surgical treatments and positive air pressure depending on the level of the disease. In treatment planning, it is essential to get rid of excess weight, if any. At the same time, avoiding smoking and alcohol can dramatically improve sleep quality.
Surgical treatment may be necessary for severe stenosis in the upper airways, but the most effective method is the use of a device called CPAP (continuous positive airway pressure). These devices support breathing by keeping the upper airways open continuously during sleep. A CPAP treatment can provide nearly one hundred percent improvement of symptoms in adults.
In addition to CPAP, BPAP (bilevel positive airway pressure) devices that provide two levels of positive pressure air can also be used to treat obstructive apnea. The high and low air pressure settings in BPAP devices can be adjusted according to the person’s breathing.