What Is a Sleep Disorder?
Reviewed by: HU Medical Review Board | Last reviewed: June 2020 | Last updated: February 2023
Simply put, a sleep disorder is a health condition that prevents you from getting enough sleep, or good quality sleep. Trouble with the timing, amount, or quality of sleep causes a range of health problems, both mental and physical. It also impacts a person’s relationships, finances, and the workplace.
Sleep disorders are common, with 10 to 20 percent of all people complaining to their doctor about sleep issues. More than one-third of people report their sleep quality as “poor” or “only fair.”1,2
What is sleep?
Sleep is a complex function of the body and is required for good health. There are 2 types of sleep:
- Rapid-eye movement (REM) which is when most dreams occur
- Non-REM which has 3 phases, including the deepest sleep
During normal sleep, a person cycles through REM and non-REM stages 3 to 5 times.1 Sleep disorders can disrupt these normal cycles.
The amount of sleep you need changes during your lifetime. On average, babies need 12 to 15 hours in a 24 hour period. Teens need 8 to 10 hours. Adults need 7 to 9 hours. But, sleep needs can vary from person to person.1,3
Why is sleep important?
People once thought of sleep as a time when the body wasn’t doing anything important. Doctors now know that sleep is an active process vital to overall health. In fact, parts of the brain and body are more active in sleep than when awake.4
During sleep, there are changes in the brain, breathing, heart rate, body temperature, and more. Sleep impacts mental abilities like judgment, concentration, mood, the ability to learn, and the ability to retain information. Physically, sleep affects weight, blood sugar, heart rate, and body temperature. Serious health problems and accident rates increase without enough sleep or good quality sleep.3-5
Types of sleep disorders
There are 6 broad categories of sleep disorder, with dozens of different subtypes, including:6
- Sleep-related breathing disorders such as sleep apnea
- Narcolepsy and other hypersomnias, or falling asleep in the day
- Sleep-related movement disorders such as restless legs syndrome and teeth grinding
- Parasomnias such as sleepwalking, night terrors, and REM sleep behavior disorders
- Circadian rhythm disorders such as shift work sleep disorders
Insomnia, or difficulty falling asleep or staying asleep, is the most common chronic, or long-term sleep disorder. Sleep apnea and restless legs syndrome are also common. Narcolepsy is less common.
Jet lag is a type of temporary sleep disorder that affects people who travel across time zones. Sleep talking is a sleep disorder that usually requires no treatment, but it may occur with other sleep disorders such as sleepwalking.
What causes sleep disorders?
There is no one cause for sleep disorders. Some sleep disorders run in families or are caused by a medical condition. However, sleep habits often contribute to too little or poor quality sleep. Unhealthy sleep habits include:7-9
- Consuming alcohol or caffeine near bedtime
- Frequent changing to your sleep or wake-up times
- An overstimulating bedtime routine
- Eating heavy meals close to bedtime
- Leaving the TV on while falling sleep
Heart and lung disease, pain, nerve disorders, depression, and anxiety are among the medical causes of sleep disorders.10
What are the symptoms of a sleep disorder?
The signs that you may have a sleep disorder vary. Some signs or symptoms of a sleep disorder include:10
- Taking more than 30 minutes to fall asleep each night
- Waking up several times throughout the night with trouble falling back asleep, or waking too early
- Feeling sleepy during the day, taking frequent naps, or falling asleep during the day
- Your partner says you snore loudly, snort, gasp, or stop breathing while you sleep
- Feeling prickly, tingling, or crawling sensations in your legs or arms, especially in the evening and when trying to fall asleep
- Your partner says your legs or arms jerk while you sleep
- Feeling like you can’t move when you first wake up
- Feeling sudden muscle weakness when you are angry, afraid, or laugh
How are sleep disorders treated?
A sleep specialist is a doctor who specializes in diagnosing and treating sleep disorders. The type of treatment your doctor recommends will depend on the type of sleep disorder you have. Common sleep disorder treatments may include:7,11,12
- Changes to sleep habits
- Prescription drugs
- Over-the-counter sleep aids
- Scheduled daytime naps
- Light therapy
- Stress reduction
- Breathing or dental devices
- Weight loss
Practicing good sleep habits, also called sleep hygiene, is often the first step to treating many sleep disorders. Your doctor will also want to rule out any other health conditions that can impact sleep.
A wide variety of health conditions can also impact sleep, including depression, anxiety, head injury, Parkinson’s disease, blindness, obesity, and post-traumatic stress disorder (PTSD).