Types of Sleep Disorders

Between 50 and 70 million adults in the U.S. report having a sleep disorder, making this a common health problem. More than 80 different types of sleep disorders exist and are divided into 6 general types:^1-2

• Insomnias
• Circadian rhythm sleep-wake disorders
• Hypersomnias
• Parasomnias
• Sleep-related breathing disorders
• Sleep-related movement disorders

Insomnia, sleep apnea, narcolepsy, and restless legs syndrome are the most common sleep disorders.

Insomnias

Insomnias are problems falling asleep, staying asleep, or waking up too early. Types include:³

• Short-term (acute) insomnia – lasts up to 3 months
• Long-term (chronic) insomnia – occurs at least 3 times a week for 3 months or longer

Circadian rhythm sleep-wake disorders

Circadian rhythm sleep-wake disorders are conditions in which sleep times get out of order.⁴

• Advanced sleep-wake phase – when someone goes to sleep several hours before normal bedtime and wakes much earlier than other people
• Delayed sleep-wake phase – when sleep and wake times are delayed by 2 or more hours
• Irregular sleep-wake rhythm – no clear sleep or wake patterns or napping throughout a 24-hour period. Also called sleep-wake rhythm disorder.
• Jet lag – occurs when someone travels across multiple time zones and the body has trouble adjusting to the new time. Often temporary.
• Non-24 hour sleep-wake rhythm – when a person’s sleep time shifts a bit each day
• Shift work disorder – changing work shifts mean that the body cannot sleep or wake on a regular schedule. Creates constant fatigue, sleepiness at work, or problems falling asleep and staying asleep.

Hypersomnias

Hypersomnias are sleep disorders that cause a person to be very sleepy or fall asleep at inconvenient or dangerous times, such as while driving.^5-7

• Idiopathic hypersomnia – creates an irresistible urge to sleep daily. A person may sleep 12-14 hours or more out of 24. “Idiopathic” means “unknown cause.”
• Insufficient sleep syndrome – regularly getting too little sleep
• Kleine-Levin syndrome – recurring bouts of excessive sleepiness that comes in episodes of 2 days to 5 weeks. Usually seen with a change in appetite, behavior, or thoughts.
• Long sleeper – people who need much more sleep than their peer group
• Narcolepsy – an uncontrollable sleep attack or severe sleepiness. Can come on while eating, working, driving, or walking. May come with the inability to move or loss of muscle tone such as knees buckling.

Parasomnias

Parasomnias involve unwanted events, dreams, or behaviors that occur during sleep. The person may appear to be awake but often has no memory of what happened.⁸

• Bedwetting – failing to wake up when the bladder is full
• Confusional arousals – confusion, not knowing where you are, or what you are doing when you wake up
• Exploding head syndrome – hearing a loud noise that is not really there just before falling asleep or waking up
• Nightmares – extreme dreams that wake you in intense fear, with or without memory of the dream
• Night terrors or sleep terrors - usually seen in children who may scream at night and appear terrified
• REM sleep behavior disorder – acting out vivid dreams as you sleep by kicking, punching, or flailing
• Sleep eating – binge eating while partly awake
• Sleep paralysis – unable to move the body when falling asleep or waking up. Lasts from a few seconds to a few minutes.
• Sleep talking – usually harmless though it may disturb a sleep partner
• Sleep walking – walking around while asleep
• Sleep hallucinations – imagined events that seem real. Usually visual, but may include sound, touch, taste, and smell.

Sleep-related breathing disorders

Sleep-related breathing disorders are breathing problems that occur during sleep.^9-13

• Central sleep apnea – a temporary stop or lessening in breathing during sleep. Usually caused by a problem in the heart or brain, not a block of the airway.
• Obstructive sleep apnea – a temporary stop in breathing during sleep caused by tissue blocking the airway. Causes heavy snoring, choking, and gasps while sleeping.
• Sleep-related hypoventilation – low blood oxygen levels during sleep from shallow, slow, or obstructed (partly blocked) breathing
• Snoring – a loud or harsh sound made while breathing as you sleep. May be a sign of a sleep disorder such as sleep apnea.

Sleep-related movement disorders

Sleep-related movement disorders cause body movement during or just before sleep, making it hard to fall or stay asleep.¹⁴

• Bruxism – grinding or clenching of teeth while sleeping
• Night leg cramps – sudden, intense pain in the leg or foot
• Periodic limb movement disorder – uncontrollable, repeating muscle movements that may wake you up
• Restless legs syndrome – burning, itching, tingling inside the legs that make it hard to fall asleep or stay asleep
• Sleep rhythmic movement disorder – repeating body movements while asleep or falling asleep. May look like body rocking or hang banging.