Sleep apnea disrupts sleep and increases risk of serious illness.
Posted Oct 03, 2008
This distressing story is a common experience for many couples. Charles later discussed his day time sleepiness and his wife's complaints about his snoring with his doctor. This led to a sleep study and a diagnosis of obstructive sleep apnea (OSA). Obstructive sleep apnea is an increasingly well known disorder and, depending on the parameters considered, affects 4% to 24% of men and 2% to 9% of women in the US. The difference in estimates mainly relates to whether or not the definition includes the criterion of excessive daytime sleepiness. Sleep apnea can occur at any age with increasing prevalence in middle and older age. Menopause is a risk factor for women. The major risk factor for sleep apnea is excess body weight with increasing risk accompanying increases in weight. Localized structural abnormalities such as enlarged adenoids and tonsils can cause sleep apnea even in normal weight individuals. Smokers appear to be at higher risk. Endocrine disorders such as hypothyroidism increase the risk for sleep apnea. Episodes of apnea are usually made worse by alcohol consumption and by nocturnal nasal congestion. Family background appears to make a difference either due to genetic or shared lifestyle factors. Sleep apnea is a significant disorder with both immediate and long range implications.
There are a number of different kinds of sleep apnea depending on what causes the sleeper to stop breathing, but the most common type is OSA. With OSA, during sleep either complete or partial obstruction of airflow occurs which may result in decreased blood oxygen levels and arousal or awakening from sleep. Typical features include snoring, breathing pauses, gasping, choking, and frequent movements. Daytime symptoms include fatigue and sleepiness. Daytime drowsiness may be so severe that car or industrial accidents occur.
OSA is the result of the upper air way becoming obstructed during sleep. Obstruction may occur anywhere in the upper airway as the muscles which keep the airway open relax with the onset of sleep. The further reduction in muscle tone that occurs during REM sleep may contribute to longer and more prominent airflow reductions during this stage of sleep. In children upper airway narrowing is most often due to enlarged tonsils and adenoids. The major cause in adults is excess weight as the increased fatty tissue contributes to the narrowing of the airway and increases obstruction.
As breathing is reduced or stopped, blood oxygen levels may decrease and carbon dioxide levels may increase. The heart needs to work harder to supply oxygen to the body at the very time that less oxygen is available to power the heart. As the brain notes the changing blood gas levels an alerting signal results in a brief arousal or awakening. This leads to an increase in muscle tone and re-establishment of airflow in the upper airway. The person is able to breathe again and falls back asleep. The process then repeats, perhaps many times during the night. Frequent arousal results in disrupted sleep and may contribute to daytime sleepiness. The cardiovascular system is stressed and does not get the rest that typically takes place during sleep.
OSA can cause disruption of the sleep of family members due to the loud snoring and frightening breathing pauses. In the individual with OSA there may be poor quality sleep, day time sleepiness, decreased cognitive functioning with poor attention, concentration and memory, and depressed mood. OSA is a significant risk factor for high blood pressure. It is associated with type II diabetes. OSA may worsen some forms of co-existing heart disease. OSA may have a causal relationship with heart attack, stroke, cardiac arrhythmia, pulmonary hypertension and depression. While weight gain is often a causative factor in sleep apnea, sleep apnea also appears to frequently result in increased weight gain that may contribute to the worsening of the sleep apnea and contribute to the increased risk of other diseases.
If you (or a loved one, adult or child), have symptoms of sleep apnea including loud and disruptive snoring, breathing pauses, nocturnal gasping or choking, and daytime sleepiness, this should be fully discussed with your physician. A sleep study may be ordered and treatment recommended. Fortunately, a number of effective treatments are now available for sleep apnea and have been shown to have a positive impact on symptoms such as daytime sleepiness and hypertension. If you have sleep apnea, getting it treated will go a long way towards preventing you, and your long-suffering bed partner, from being sleepless in America.