Sleep Disorders Center


The Dyssomnias are sleep disorders that either cause difficulty initiating or maintaining sleep, or cause excessive sleepiness. The most common dyssomnias include snoring and obstructive sleep apnea (OSA), insomnia, restless legs syndrome (RLS) and periodic limb movement disorder (PLMD), narcolepsy, and circadian rhythm disorders.

Snoring and Obstructive Sleep Apnea

Primary snoring is characterized by loud upper airway sounds during sleep. As much as 60% of the population snores at one time or another and the prevalence increases with age. Although primary snoring is not life threatening, it can be considered a social nuisance. In recent polls conducted by the National Sleep Foundation, 31% of Americans take measures to deal with their partner's snoring on a regular basis. These include sleeping in another room or using earplugs to block the noise. Many treatments are available for snoring, including nasal strips, throat sprays, prescription nose medications, mouth guards and various surgical procedures aimed at reducing the amount of tissue at the back of the throat.

Obstructive Sleep Apnea (OSA) is characterized by the recurrent collapse of the upper airway at the level of the soft palate and tongue during sleep. Obesity, facial deformities and enlarged upper airway structures can contribute to the airway's collapse. Apneas are associated with oxygen deprivation and can cause cardiac arrhythmias, or irregular heartbeats, during sleep. Although generally unnoticed by the sleeper, apneas cause repetitive and brief arousals, leading to poor sleep quality and daytime sleepiness. Patients suffering from OSA may experience difficulty with concentration or memory, poor mood control, impotence or feelings of depression. They may also suffer from hypertension (high blood pressure), heart failure or abnormal heartbeats. If left untreated, OSA can increase the risk for sudden heart attack or stroke by as much as 60%. The good news is OSA is a very treatable condition. Treatment options can range from Continuous Positive Airway Pressure (CPAP) to surgery to dental implants.

A careful sleep history and an overnight sleep study are used to distinguish primary snoring from OSA.


Insomnia can mean difficulty falling asleep, difficulty staying asleep, waking up too early, or sleep that is chronically nonrestorative or of poor quality. According to the National Sleep Foundation, about one-half of America's adults say they frequently experience at least one symptom of insomnia. Insomnia is characterized as being either acute, chronic, or primary. Acute insomnia lasts less than one month. Chronic insomnia occurs consistently for one month or longer and is likely to be associated with an underlying medical or psychological condition. Primary insomnia is often lifelong and occurs without an underlying cause. When acute insomnia is not addressed, poor sleep can become a habit. The insomniac continually expects that he or she will have difficulty sleeping, a vicious cycle occurs, and insomnia can become long term.

There are pharmacological and behavioral treatments for insomnia, and these two approaches are often combined. For acute or chronic insomnia, a sleep specialist will determine if there is an underlying problem and treat this condition first. Behavioral treatments include stimulus control, sleep restriction, cognitive behavioral therapy and relaxation training.

Pharmacological treatments for insomnia include over-the-counter (OTC) medications and prescription hypnotics. OTCs are usually antihistamines and have ingredients that may leave a person feeling groggy and less alert in the morning. They stay in the body longer and side effects may include headaches, nausea, reduced reaction times and dizziness. The Food and Drug Administration (FDA) has approved many sleep promoting medications, called hypnotics. These sleep medications are effective with fewer side effects than other sleeping medications, and are usually prescribed for short periods of time.

A careful sleep history, including a review of current medications, and sometimes an overnight sleep study are used to determine the cause of insomnia.

Restless Legs Syndrome (RLS) and Periodic Limb Movement Disorder (PLMD)

Restless Legs Syndrome (RLS) is a neurological movement disorder, and is often referred to as the most common medical problem ever heard of. It affects an estimated 12 million adults, usually those in middle age, but it may first appear in children as growing pains. It is more prevalent in women than men, often first appearing during pregnancy. The National Sleep Foundation found 17% of adults, ages 55-84, reported symptoms of RLS, which include unpleasant feelings in the legs and an urge to move them. These unpleasant feelings are often described as tingling, pulling,, creeping or nervousness in the limbs and are more prevalent in the evening and at night, resulting in disrupted sleep. Family history accounts for approximately one-half of those diagnosed. Anemia, or low iron levels, has also been found to be contributors.

Many RLS sufferers also experience Periodic Limb Movement Disorder (PLMD) during the night. PLMD is characterized by periodic jerking or kicking of the legs making it difficult to fall and stay asleep. This results in sleep deprivation and daytime sleepiness for the individual, and also disturbs the sleep of a bed partner.

A detailed sleep history, certain blood tests, and sometimes an overnight sleep study, are required to diagnose RLS and PLMD.


Narcolepsy affects approximately one in 2000 people, and its cause is unknown at this time. Onset occurs mostly between the ages of 15 and 25 years. The primary symptom is excessive daytime sleepiness with uncontrollable urges to sleep. Other symptoms vary among individuals, but can include cataplexy (episodes of muscle weakness during intense emotions), sleep paralysis (brief paralysis at sleep onset or awakening), and/or hypnogogic hallucinations (dreams that continue into wakefulness). Untreated, narcolepsy can severely impair many areas of an individual's functioning, including the ability to safely operate a car or maintain employment.

A careful sleep history which includes a review of current medications, and an overnight sleep study followed by a daytime nap study are required to diagnose narcolepsy.

Circadian Rhythm Disorders

Circadian rhythm sleep disorders are those that are related to the timing of sleep within the 24-hour day. They can include Delayed Sleep Phase Syndrome, Advanced Sleep Phase Syndrome and Shift Work Sleep Disorder.

Delayed Sleep Phase Syndrome (DSPS) is marked by sleep onset and wake times that are later than desired in order to fulfill social and work obligations. Typically DSPS patients are frustrated by their attempts to fall asleep and arise earlier. They are considered night people, preferring to stay up later, and sleep in, in the morning. Very often, medication has little to no effect in aiding sleep onset, and may aggravate the daytime symptoms of sleepiness and difficulty awakening.

Advanced Sleep Phase Syndrome (ASPS) is a disorder characterized by the inability to delay sleep onset and final morning awakening. Although a mild degree of ASPS may be a normal part of aging, frustration may occur at the difficulty remaining awake in the evening and the early morning insomnia that accompany this disorder.

Shift Work Sleep Disorder (SWSD) can be very challenging as shift work requires sleep in the daytime, when our natural instinct is to remain awake. The day sleeper may experience sleep onset insomnia, difficulty remaining asleep, complaints of unrefreshed sleep and difficulty remaining awake during their work shift.

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