The Most Common Sleep Disorders Explained

4 min read

Last Modified 1 June 2023 First Added 14 January 2020

By Anna Ashbarry

What is a sleep disorder?

A sleep disorder is a condition whereby the quality, quantity or timing of an individual’s sleep is impacting on them during the day. There are many different types of sleep disorders, all with their own symptoms, causes and treatments.

Many people suffer from occasional sleep issues, where their normal routine is thrown off. However, a sleep disorder is a chronic problem that interferes with your quality of life.


What are the most common sleep disorders?

Adults and children can be affected by sleep disorders. Children typically require more sleep than adults so sometimes, it can be harder to recognise if your child has a sleep disorder. Read on to learn more about the different types of sleeping disorders.

1. Parasomnia

Parasomnia is the name for a group of sleep disorders. These disorders include confusion arousal, sleepwalking, sleep terrors, sleep eating disorder, REM sleep behaviour disorder, sleep paralysis, nightmares, bedwetting, sleep hallucinations, sleep talking and exploding head syndrome. All of these disorders involve unwanted events or experiences when you are falling asleep, during the night, or waking up.

2. Sleep Apnoea

This is a disorder where breathing repeatedly stops and starts throughout the night. People who are diagnosed with sleep apnoea often snore very loudly and feel tired and sluggish each day. Treatment for sleep apnoea sometimes involves the use of a breathing device which is to be worn each night during sleep.

3. Insomnia

A person with insomnia struggles to fall asleep at night. Sometimes insomnia also involves waking in the middle of the night or early morning, and not being able to fall back to sleep again.

4. Hypersomnia

Hypersomnia is often referred to as excessive daytime sleepiness. This sleep disorder can also involve excessive time spent sleeping. People with this disorder typically struggle to stay awake during the daytime.

5. Narcolepsy

As one of the least common sleeping disorders, narcolepsy roughly affects only 1 in 2,200 to 3,000 people. People who have narcolepsy often face sleep attacks, sleep paralysis, cataplexy, hallucinations and excessive sleepiness.

6. Restless Legs Syndrome (RLS)

RLS causes discomfort when falling asleep as people with this disorder get sudden urges to move their legs. Unpleasant sensations such as itching and tingling can also occur in the feet, calves and thighs. It is said that personal habits such as smoking can worsen RLS, while regular daytime exercise can alleviate symptoms.

7. Periodic Limb Movement Disorder (PLMD)

If you involuntarily move your limbs throughout the night you may have PLMD. This sleep disorder involves repetitive jerking and cramping of limbs during the night. The lower limbs of the body are more commonly affected.  The key difference between PLMD and RLS is that RLS occurs while awake and PLMD occurs while sleeping.

8. Circadian rhythm sleep disorders

This category of sleep disorders involves conditions such as jet lag, shift work disorder, non-24-hour sleep-wake disorder and delayed sleep-wake phase disorder. People that have one or more of these disorders tend to not sleep at what is considered normal times of the night.

9. Bruxism

Considered to be a sleep-related movement disorder, bruxism is where a person grinds their teeth throughout the night. This condition is fairly common and has many possible causes. However, the most common cause is often stress or anxiety

10. Seasonal Affective Disorder (SAD)

Often referred to as ‘winter depression’, people with SAD are often most affected in the winter season and struggle with waking up in the morning, a lack of energy, the urge to sleep in the day and sleeping for longer than normal at night.

image of man unable to sleep


What causes sleep disorders?

Sleep disorders are often caused by other underlying medical issues such as heart disease, pain disorders, and mental illnesses. Sometimes they can be brought on by medications, and sometimes, they are simply genetic or unknown in cause.

While sleep problems are usually down to lifestyle factors like shift work, consuming caffeine or alcohol, or even ageing.

How common are sleep disorders?

Sleep problems are becoming increasingly more common. In the UK, as many as 16 million adults are suffering from sleep struggles and around 48% of the UK population admit they don’t get the recommended 7-9 hours of sleep each night. A survey of the nation’s sleep habits also discovered that 30% of people in the UK are severely sleep-deprived and that almost a third of the population is suffering from insomnia.

How are sleep disorders treated?

If you have tried all the tips and tricks on how to sleep better and suspect that you have a sleep disorder, the best thing to do is contact your GP. Make a sleep diary that explains the timings, quantity, and quality of your sleep, as well as other symptoms. This will help your doctor assess the best course of action and help you to get on your way to more restful nights.

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