An Overview of Sleep Apnea

Sleep apnea is a common condition that affects millions of Americans. The chronic breathing disorder in which one repeatedly stops breathing during the night may be due to a partial or complete obstruction (or collapse) of the upper airway, typically affecting the base of the tongue and the soft palate.

It also may occur due to a depressed signal from the brainstem to initiate a breath. These events last 10 seconds or longer, and may occur hundreds of times per night. Someone with sleep apnea may experience loud snoring, brief pauses in breathing, and intermittent gasping. During apnea events, the oxygen level of the blood drops, the heart rate increases, and sleep becomes disrupted as the affected person wakes up to resume breathing. This can have significant consequences on one's sleep quality, daytime function, and overall health.

Sleep apnea is a generic term that includes any disorder that causes pauses in breathing during sleep. It may affect someone at any age, but the prevalence of sleep apnea increases beyond middle age. There are a few major sub-types, including:

• Obstructive Sleep Apnea
• Central Sleep Apnea
• Complex Sleep Apnea

Sleep apnea is not the only problem that can lead to difficulties breathing during sleep. There are a few other problems that do not cause a complete pause in the breathing but may still be problematic, such as:

• Snoring
• Catathrenia or sleep groaning
• Upper Airway Resistance Syndrome (UARS)

It is also important to recognize that oxygen levels may drop during sleep if lung function is compromised due to pulmonary disease, and this would require distinct treatment.

Aside from the pauses in breathing which are typical of the disorder, there are many other common symptoms in sleep apnea. These symptoms may include:

• Loud, chronic snoring
• Choking or gasping during sleep
• Witnessed pauses in breathing during sleep
• Waking frequently to urinate (nocturia)
• Teeth grinding or clenching (bruxism)
• Dry throat or mouth upon awakening
• Nocturnal palpitations or a racing heart rate
• Night sweats
• Nocturnal heartburn
• Frequent nighttime awakenings and insomnia
• Excessive daytime sleepiness
• Morning headache
• Short-term memory or learning problems
• Feeling irritable
• Poor concentration or attention
• Changes in mood, including depression

Not all of these symptoms must be present for the condition to occur, and children with sleep apnea may present with different complaints like growth problems, attention deficit hyperactivity disorder, and restless sleep.

There are a few common causes of obstructive sleep apnea and situations that can make it worse, including:

• Being overweight or obese (including a large neck size)
• Abnormal upper airway anatomy (including a deviated septum)
• Using medications, drugs, or alcohol
• Aging
• Sleeping on the back
• REM or dreaming sleep
• Smoking

In addition, central sleep apnea may occur due to a stroke, heart failure, or the use of narcotic or opioid pain medications. Complex sleep apnea occurs with certain treatments.

Sleep apnea is actually relatively common. When sleep apnea is defined as having more than 5 apneic events per hour that result in a symptom (such as excessive daytime sleepiness), then some 2 to 9 percent of people would be afflicted with sleep apnea. When defined as having more than 5 apneic events per hour without self-reported symptoms, the prevalence is 9-24% in general population. Because cardiovascular complications of sleep apnea occur regardless of the presence of daytime symptoms such as sleepiness, the later is considered a true prevalence.

The prevalence increases from 18 to 45 years of age and then reaches a plateau from 55 to 65 years of age. If someone will develop sleep apnea, they will typically do so by that age. It is approximately twice as common among men.

The diagnosis of sleep apnea often depends on a careful history and physical examination by a qualified, board-certified sleep medicine physician. Further testing is accomplished using a set of standard diagnostic tests, potentially including:

• Polysomnography
• Home Sleep Apnea Testing
• Multiple Sleep Latency Testing (MSLT)
• Maintenance of Wakefulness Test (MWT)
• Overnight Oximetry
• Epworth Sleepiness Scale
• Sleep Log

In general, either a home sleep apnea test or an attended diagnostic polysomnogram that is done in a testing center are the only tests required to diagnose sleep apnea.

Sleep apnea can be effectively treated in several ways. In general, most individuals will be tried on continuous positive airway pressure (CPAP). This requires choosing a CPAP mask. A similar treatment called bilevel positive airway pressure (BiPAP) is also sometimes used. It may take some time to get used to these therapies, and there are some guidelines that might help solve problems. There are some accommodations such as a chinstrap that can prevent mouth breathing. In addition, it is important to keep your CPAP clean. It is also possible to monitor your CPAP use.

For those who cannot tolerate CPAP, there are some alternative treatments to CPAP. These may include oral appliances, positional therapy, or surgeries. In some cases, when excessive daytime sleepiness persists despite treatment, stimulants such as Ritalin, Provigil, and Nuvigil may be necessary to treat the sleepiness. Even quirky alternatives such as playing the didgeridoo have been shown to be an effective treatment. Some individuals may find benefits from caffeine or even scheduled naps. As always, individuals with sleep disorders benefit from observing better sleep guidelines.

There can be serious consequences—even deadly ones—to untreated sleep apnea, such as:

• Stroke or transient ischemic attacks
• Coronary heart disease
• Heart failure
• Irregular heartbeat
• Heart attack
• High blood pressure
• Heartburn and reflux
• Diabetes
• Erectile dysfunction
• Concentration and memory problems (dementia)
• Depression
• Sudden death

There are separate consequences of sleep apnea in children, which may include hyperactivity, slowed growth, and decreased intelligence.

Conclusion

Sleep apnea is a relatively common disorder that involves pauses in breathing that occur during sleep. There are various sub-types of sleep apnea, and it may be more common in specific populations. The symptoms that result often include excessive daytime sleepiness, but there can also be serious - and even deadly - consequences. There are several conditions that may cause sleep apnea or make it worse. Diagnosis typically relies on a careful history and physical examination by a physician and a sleep study such as a home sleep apnea test or an in-center polysomnogram. Treatment may be accomplished with the use of continuous positive airway pressure (CPAP) or other alternative therapies such as oral appliances or even surgery. There may be certain accommodations that must be arranged in order to maximize therapy compliance. Fortunately, sleep apnea can often be successfully treated with favorable results.