Obstructive Sleep Apnea: Causes & Treatments (original) (raw)
Obstructive sleep apnea (OSA) is caused by the collapse of the upper airway during sleep. The muscles supporting soft tissues in the throat relax, narrowing or closing the airway and temporarily interrupting breathing.
OSA is the most common sleep-related breathing disorder.
Normally, air should flow smoothly from the mouth and nose into the lungs at all times, including during sleep.
Periods when breathing stops completely are called apnea or apneic episodes. In OSA, the normal flow of air is repeatedly stopped throughout the night.
OSA is most common among older males, but it can affect anyone, including children. The incidence rises following menopause, such that the rates are similar in men and postmenopausal women.
Snoring is often associated with OSA, especially if the snoring is interrupted by periods of silence. Snoring is caused by airflow squeezing through the narrowed airway space.
It is important to remember that snoring doesn’t necessarily indicate something potentially serious, and not everyone who snores has OSA.
Untreated OSA can cause serious health problems such as:
- high blood pressure (hypertension)
- heart disease
- stroke
- diabetes
- atrial fibrillation (abnormal heart rhythm)
- pulmonary hypertension
Proper diagnosis and treatment are essential for preventing complications.
Most people with OSA complain of daytime sleepiness. OSA causes episodes of decreased oxygen supply to the brain and other parts of the body, so sleep quality is poor. This causes daytime drowsiness and a lack of clarity in the morning.
Those who share beds with people with OSA may report the following:
- loud snoring
- gasping
- choking
- snorting
- interruptions in breathing while sleeping
These symptoms are also often detected when checking on another complaint or during health maintenance screening.
People with OSA may also experience the following symptoms:
- morning headaches
- feeling disgruntled or grumpy
- forgetfulness
- drowsiness
- repetitive awakenings throughout the night
Other symptoms include:
- hyperactivity in children
- worsening depression
- poor job and school performance
- loss of interest in sex
Daytime drowsiness puts people with sleep apnea at risk for motor vehicle crashes and industrial accidents. Treatment can help to completely relieve daytime drowsiness.
The following are some conditions associated with OSA:
- obesity hypoventilation syndrome, a breathing disorder in people with obesity
- endocrine conditions, such as hypothyroidism, acromegaly, and polycystic ovary syndrome, which may affect your breathing when you’re asleep
- chronic lung disease, such as asthma, chronic obstructive pulmonary disease (COPD), and pulmonary fibrosis
- neuromuscular conditions, such as a stroke, which can interfere with brain signals to your chest muscles and airway
- heart or kidney failure, which may cause fluid to build up in your neck and obstruct the upper airway
- pregnancy
The risk for OSA increases if you have physical features that narrow your upper airway. Risk factors of OSA include:
- obesity
- large tonsils
- men with a collar size of 17 inches or more
- women with a collar size of 16 inches or more
- a large tongue, which can block the airway
- retrognathia, which is when your lower jaw is shorter than your upper jaw
- a narrow palate or airway that collapses more easily
- smoking
- family history of OSA
A diagnosis of sleep apnea begins with a complete history and physical examination. A history of daytime sleepiness and snoring are important clues.
Your doctor will examine your head and neck to identify any physical factors that are associated with sleep apnea.
Your doctor may ask you to fill out a questionnaire about daytime drowsiness, sleep habits, and quality of sleep.
In some cases, the evaluation for OSA may be performed at home without a technician in attendance. However, home sleep apnea testing is only useful for the diagnosis of OSA in certain people. It is not a substitute for other diagnostic tests if other sleep disorders are suspected.
The following tests may be performed to diagnose OSA.
Polysomnography (PSG)
During a polysomnography, you sleep overnight in a hospital or sleep center while connected to a variety of monitoring devices that record physiologic variables.
Patterns of physiologic abnormalities during sleep may indicate sleep-disordered breathing as well as many other sleep disorders.
While you sleep, the PSG will measure the activity of different organ systems associated with sleep. It may include:
- electroencephalogram (EEG), which measures brain waves
- electrooculogram (EOM), which measures eye movement
- electromyography (EMG), which measures muscle activity
- electrocardiogram (ECG), which measures heart rate and rhythm
- pulse oximetry test, which measures changes in your oxygen levels in your blood
EEG and EOM
During an EEG, electrodes are attached to your scalp that will monitor brain waves before, during, and after sleep. The EOM records eye movement.
A small electrode is placed 1 centimeter above the outer upper corner of your right eye, and another is placed 1 centimeter below the outer lower corner of your left eye. When your eyes move away from the center, this movement is recorded.
Brain waves and eye movements tell doctors about the timing of the different phases of sleep. The two broad phases of sleep are non-REM (non-rapid eye movement) and REM (rapid eye movement).
Decreased muscle tone and paralysis occur during REM sleep.
EMG
During an EMG, two electrodes are placed on your chin: one above your jawline and the other below it. Other electrodes are placed on each shin.
The EMG electrodes pick up the electrical activity generated during muscle movements. Muscle relaxation should occur during sleep. The EMG picks up when your muscles relax and move while you’re sleeping.
ECG
A single lead ECG records the electrical signals from your heart during the sleep study to monitor your heart rate and rhythm.
Pulse oximetry
In this test, a device called a pulse oximeter is clipped onto a thin area of your body that has good blood flow, such as a fingertip or earlobe.
The pulse oximeter uses a tiny emitter with red and infrared LEDs to measure the oxygen saturation level of your blood. This level may decrease during episodes of apnea.
The goal for the treatment of OSA is to make sure airflow isn’t obstructed during sleep. Treatment methods include the following:
Weight loss
Weight management and exercise are usually recommended for people with OSA who also have obesity.
Although it may not lead to complete remission, weight loss has been shown to decrease the severity of OSA.
Losing weight, if your doctor has recommended it, could also reduce blood pressure, improve your quality of life, and decrease daytime sleepiness.
Continuous positive airway pressure (CPAP)
The face mask gently delivers positive airflow to keep the airways open at night. The positive airflow props the airways open.
CPAP is a highly effective treatment for OSA.
For people with mild or moderate OSA who don’t benefit from CPAP therapy, an oral appliance is a reasonable alternative to positive airway pressure.
Bilevel positive airway pressure (BPAP)
BPAP machines, sometimes called BiPAP machines, have settings that deliver two pressures in response to your breathing: inhaled pressure and exhaled pressure. This means the pressure changes during inhaling versus exhaling.
Sleeping on your side
Since sleeping on your back (supine position) can make OSA worse for some people, positional therapy is used to help you learn to sleep on your side.
Surgery
There is no consensus regarding the role of surgery in adult patients with OSA. In general, you may consider surgical therapy when CPAP or BPAP machines or an oral appliance aren’t effective.
Surgical treatment may be the most effective for people who have OSA due to a severe, surgically correctable, obstructing lesion of the upper airway.
Being a surgical candidate depends on factors such as:
- your desire to have surgery
- if you have a surgically correctable problem
- your overall health to undergo surgery
Surgical evaluation begins with a physical exam to check on the anatomy of your upper airway.
In addition, your doctor will insert a flexible laryngoscopy, a thin instrument inserted through your nose that lights and magnifies the upper airway, while you are awake or, if necessary, asleep.
Surgical treatment for OSA provides long-term benefits in some patients, although the complete elimination of OSA is often not achieved, depending on the specific procedure.
You should always talk with your doctor if you’re experiencing daytime drowsiness or having consistent problems sleeping.
OSA has many treatment options to help you manage symptoms. Your doctor will create a treatment plan that combines lifestyle changes and other therapies.