Many medical conditions may lead to a disruption of sleep, or an excessive amount of daytime sleepiness, and are called sleep disorders. These may be caused by physiological or psychological factors. Some of the more common sleep disorders include:
Snoring and Sleep Apnea
Snoring may seem benign, but it may represent a difficulty in keeping the throat open while one sleeps. Its more serious companion, sleep apnea, is a chronic medical condition where the affected person repeatedly stops breathing during sleep. These episodes last 10 seconds or more and cause oxygen levels in the blood to drop. It can be caused by obstruction of the upper airway, resulting in obstructive sleep apnea, or by a failure of the brain to initiate a breath, called central sleep apnea. It can cause and worsen other medical conditions, including hypertension, heart failure, and diabetes.
Insomnia
Insomnia is an inability to obtain a sufficient amount of sleep to feel rested and can be characterized either by difficulty falling or staying asleep. It is the most common sleep disorder, with many potential causes. One of the sub-types is acute insomnia and a rare type that runs in families may even be fatal.
Parasomnias
From the Latin meaning "around sleep," parasomnias are a sleep disorder characterized by abnormal sleep behaviors. Parasomnias involve unconscious complex, semi-purposeful, and goal-directed behaviors that have meaning or importance to the individual. These can include sleep terrors, sleepwalking, sleep eating, sleep sex, rapid eye movement (REM) behavior disorder, or any number of potential behaviors that occur while the person remains asleep.
Sleep Paralysis
Sleep paralysis is characterized by a temporary inability to move while transitioning from sleep to wakefulness, such as when falling asleep or waking up. It may be frightening as one may seem to be awake, but unable to move. It is common, but may also be a symptom of narcolepsy.
Restless Legs Syndrome
Restless legs syndrome is a neurological movement disorder characterized by unpleasant feelings in the legs associated with a need to move. These sensations may include aches, burning, tingling, or the feeling of bugs crawling on the legs. These symptoms may occur at rest or at night making it hard to fall or stay asleep. RLS has many potential causes, including iron deficiency, pregnancy, and obesity. It may be associated with periodic limb movements of sleep (PLMS)
