Common Sleep Disorders
Approximately 40% of the adult population suffers from snoring. Snoring is the result of vibration of membranous tissues of the upper airway caused by a disruption in the flow of air. Often multiple tissues are responsible and any non-cartilaginous tissues can be involved.
At the onset of normal sleep the muscles of the upper airway relax causing the airway to lose patency and collapse. In the presence of structural abnormalities that further narrow the airway, snoring can occur. Persons with enlarged tissues such as the tongue, tonsils and uvula are at increased risk of snoring. A small, retracted jaw and thick neck are also common amongst snorers.
Although further study is required to ascertain whether snoring itself poses any health risks, it is often indicative of more severe sleep disordered breathing. Most patients being treated for sleep apnea first sought out help because of their snoring. Treatment for snoring usually consists of lifestyle modification, use of an oral appliance, or surgery.
Sleep apnea is characterized by the complete cessation of breathing during sleep for a minimum of ten seconds per apneic event. There are several types of sleep apnea differentiated by their root causes. Central Sleep Apnea occurs when the brain does not properly regulate breathing during sleep. Obstructive Sleep Apnea occurs when tissues of the upper airway obstruct the flow of air. Mixed or Complex Sleep Apnea occurs when a patient is suffering from both Central and Obstructive Sleep Apnea. Often Complex sleep apnea is not diagnosed until after a patient has been treated for
Obstructive Sleep Apnea.
Severe sleep apnea is treated using a CPAP machine, in mild to moderate cases or where CPAP has been shown to be ineffective, an oral appliance can be used. In certain cases where CPAP and oral appliances are ineffectual surgery is sometimes used to treat sleep apnea.
Restless Leg Syndrome/Periodic Limb Movement
Restless Leg Syndrome/ Periodic Limb Movement is a neurological condition characterized by uncomfortable sensations in and rhythmic, involuntary movement of the limbs while at rest. These symptoms tend to worsen in the evening and at night and often are only alleviated with activity. Most commonly observed in the lower extremities, more severe cases sometimes involve the arms as well. The exact cause of the condition is unknown, but there is increasing evidence of brain iron deficiency playing a role. Restless Leg Syndrome is treated using a variety of medications including anticonvulsants, opioids, dopaminergic agents and benzodiazepines.
Symptoms of narcolepsy include excessive daytime sleepiness leading to abrupt “sleep attacks” at inappropriate times, cataplexy, sleep paralysis and vivid hallucinations at the onset of sleep. Not all of these symptoms are seen in every patient and not everyone experiencing them has narcolepsy. The only symptom exclusive to narcolepsy is cataplexy and it occurs in 60-70% of narcoleptics.
Cataplexy is the abrupt loss of muscle tone caused by an emotional response such as anger, laughter or surprise. There is a range of severity but any voluntary skeletal muscles can be involved. A typical attack can involve a sagging jaw, head falling forward, arms dropping to the sides and a buckling of the knees.
Narcolepsy is currently treated using stimulants such as modafinil and sodium oxybate.
Insomnia is a very broad category of sleep disorder. Types of insomnia include sleep-onset, sleep maintenance, early morning waking, or a combination of these. Insomnia can also be chronic (>6 months), intermittent or acute (<1 month). Because of this complexity definitions of insomnia are many and varied, but most recently the consensus is that insomniacs must display one sleep symptom as well as one wake symptom. Sleep symptoms include difficulty initiating or maintaining sleep, early morning waking, and waking feeling un-refreshed. Wake symptoms include sleep-associated daytime impairments such as sleepiness, fatigue, moodiness, cognitive difficulties, and social or occupational impairment.
Insomnia is treated using cognitive behavioural treatment and pharmaceuticals such as hypnotics (zolpidem) or medications that act upon melatonin (Ramelteon) or serotonin (doxepin) receptors.
Parasomnias include a large number of sleep disorders, the most common being sleep walking and abnormal dream behaviours known as nightmares.
Sleepwalking has been known to run in families and be more common in children. A person who is sleepwalking appears to be awake, moves around and can even engage in conversations.
Nightmares and night terrors both cause a person to feel fear, terror and/or anxiety. A person suffering from night terrors awakens in a fearful state and is usually confused, incapable to communicate and unable to awaken fully. Often patients who suffer from night terrors also experience sleepwalking.