Sleep Apnea is a condition whereby one stops breathing during sleep. Apnea is derived from the Greek word meaning “want of breath”. Sleep Apnea is typically caused by an obstruction in the upper airway. This obstruction can be in the nasal passages (enlarged turbinates, deviated septum, etc) or oral airway (enlarged tonsils, enlarged adenoids, enlarged tongue, soft palate, retrognathia [recessed chin], micrognathia [small chin], or an enlarged uvula). Those who suffer from sleep apnea are at greater risk for high blood pressure, cardiac arrhythmias (irregular heartbeats), stroke, and death. There are various forms of treatment for Sleep Apnea such as CPAP (Continuous Positive Airway Pressure), surgery, dental devices, weight loss, and/or positional therapy.
Prevalence of Sleep Apnea
Sleep apnea is a sleep-related breathing disorder that affects an estimated 18 million Americans (3 – 7% of men and between 2 – 5% of women). The prevalence of this condition is much higher in:
- people with cardiac or metabolic disorders such as diabetes
- those over 40, and
- those who are overweight
Characteristics of Sleep Apnea
Sleep apnea is characterized by multiple respiratory pauses during sleep. These pauses, or “apneas,” are defined as periods of 10 seconds or longer during which the sleeper stops breathing altogether. Other, milder respiratory events during sleep known as “hypopneas” are defined as periods lasting 10 seconds or longer during which breathing is significantly reduced and oxygen saturation falls. Most people with sleep apnea will have periods of abnormal breathing that last between 30 and 40 seconds more than 400 times per night. So the average person with sleep apnea spends more than 3 hours a night when he’s not breathing normally – or not breathing at all!
People with sleep apnea report a number of symptoms that they often fail to report as problems, and thus miss detection by healthcare professionals. (Note: a spouse or bed partner often provides helpful information about the sleep and daytime functioning of the sufferer.)
Symptoms of Sleep Apnea:
- Loud snoring
- Snoring interrupted by gasping, snorting, or choking
- Excessive daytime sleepiness, often with the tendency to fall sleep in inappropriate situations such as while at work, while watching movies, or while driving
- Trouble with attention, concentration, or memory
- Low mood, depression, or irritability
- Loss of sexual interest, impotence (in men), or menstrual irregularities (in women)
- “Acid stomach,” or heartburn at night
- Dry mouth upon awakening > Headaches upon awakening
- Nausea upon awakening
- Frequent nighttime urination or even bedwetting
Other Symptoms Include:
- Morning headache
- Cognitive difficulties, such as poor memory/concentration
- Personality changes – depression
- Gastro-esophageal reflux
- Frequent nocturnal urination
- Morning sore throat
- Morning dry mouth
- Chest and limb pain
Risks of Sleep Apnea
Sleep apnea is associated with significant health and safety risks:
- High blood pressure. One review of the medical literature reports that approximately 6 of every 10 people with sleep apnea suffers from high blood pressure.
- Irregular heartbeats. Heart rhythms that are either too slow or too fast, or rhythms that are abnormal (such as premature ventricular contractions, or PVCs) occur in about half of those with sleep apnea.
- Stroke is approximately 10 times greater in those with sleep apnea than those without.
- Low blood oxygen, a common occurrence in people with sleep apnea, appears to be associated with a number of medical problems. This condition may result in seizure during sleep.
- Death rates are higher in those with sleep apnea or untreated than those without.
- Excessive daytime sleepiness: Sleepiness is a “hallmark” of sleep apnea, and often results in impaired daytime functioning. People with sleep apnea may be at greater risk of accidents or injuries due to fatigue. For example, people with sleep apnea are five times more likely to be involved in a fatigue-related motor vehicle accident than healthy individuals.
Diagnosis of Sleep Apnea
As with any medical condition, a sleep apnea diagnosis is made by a physician. If sleep apnea is suspected after evaluating a patient, some form of sleep study is indicated to establish a diagnosis. Currently, an overnight in-laboratory sleep study (polysomnography) is a commonly used test for diagnosing sleep apnea. It requires an overnight stay in a sleep laboratory and includes evaluation of sleep staging, airflow and ventilatory effort, arterial oxygen saturation, electrocardiogram, body position and periodic limb movements.
The results of a sleep study will show both the type of sleep apnea, and provide a number of measures of its severity. The Apnea Index (AI) is the number of apneas per hour. Hypopnea is defined as a decrease in airflow of 50% or more (without complete cessation) for more than ten seconds accompanied by a drop in oxygen saturation of 2-4 percent, and the Hypopnea Index (HI) is the number of hypopneas per hour. Finally, the Apnea/Hypopnea Index (AHI) is the sum of AI and HI. The exact definition of sleep apnea in terms of the AHI was established by the American Academy of Sleep Medicine Task Force (Sleep 1999;22:667-689). Normal is AHI 0-5, mild 5-15, moderate 15-30, and severe 30+.
The degree and frequency of oxygen desaturations may also be an important parameter, particularly in patients with cardiovascular compromise. In general, most clinicians use a subjective mild/moderate/severe classification if referring to oxygen desaturations.
Treatments of Sleep Apnea
There are many treatments for sleep apnea. Weight loss is a common recommendation for overweight people with sleep apnea. However, most doctors usually recommend treatment with nasal continuous positive airway pressure (CPAP). CPAP is delivered using a small bedside machine that is attached to a plastic hose and nose mask worn by the sleeper. The machine gently delivers air that helps the sleeper breathe normally. Effective surgical treatments are available, including those offered by Ear, Nose, and Throat specialists, and weight loss specialists. Mild cases of sleep apnea may benefit from the use of an oral appliance.