We all need good, quality sleep as it is crucial for our health. Sleep disorders are a serious issue that must be addressed as soon as symptoms arise.
A 2018 study conducted in Eastern Europe found that the most frequently reported sleep disorders are insomnia, narcolepsy, sleepwalking, night terrors, nightmares, and snoring.
In this article, we will explore:
- What is sleep from a scientific perspective?
- What are sleep disorders?
- What are the most common sleep disorders?
- How can sleep disorders be treated?
What is Sleep?
From a scientific standpoint, sleep is a state of reduced sensitivity to stimuli, partial inertia, and slowed bodily functions, along with temporary loss of consciousness, occurring in humans and animals in circadian cycles alternating with wakefulness.
We only feel rested when sleep lasts long enough and includes all sleep phases. Well-rested individuals have more energy, experience less stress, and are better equipped to handle daily challenges.
How Much Sleep Do We Need?
A healthy sleep duration is approximately 8 hours per night. Both too little and too much sleep can have negative consequences. Chronic sleep deprivation can lead to hallucinations, delusions, and cognitive impairments, and shortened or prolonged sleep durations have been linked to life expectancy.
Sleep Phases and Cycles
Sleep consists of several phases that follow one another in cycles. A full sleep cycle lasts about 90–120 minutes and typically repeats 4–6 times per night. Learn more in our article: Everything You Need to Know About Sleep Phases.
Ideally, we sleep without interruptions, but many people suffer from sleep disorders. Studies show that insomnia affects about 35% of people in Eastern Europe, while excessive daytime sleepiness affects around 7.1% of the population.
Types of Sleep Disorders
There are many types of sleep disorders, classified as follows:
- Dyssomnias – disorders related to sleep quantity and quality.
- Parasomnias – unwanted physical behaviors that occur during sleep.
- Secondary sleep disorders – related to psychological or medical conditions.
It is important to differentiate between primary and secondary sleep disorders. For example, anxiety and depression can either cause sleep disturbances or result from them.
Common Sleep Disorders
Here are some of the most common types of sleep disorders:
- Bruxism – involuntary teeth grinding during sleep.
- Delayed Sleep Phase Syndrome – a circadian rhythm disorder where sleep cycles are delayed.
- Hypopnea Syndrome – reduced breathing during sleep.
- Idiopathic Hypersomnia – chronic excessive daytime sleepiness.
- Primary Insomnia – difficulty falling or staying asleep without any identifiable cause.
- Klein-Levin Syndrome – recurrent episodes of excessive sleepiness, confusion, compulsive eating, and behavioral changes.
- Narcolepsy – excessive daytime sleepiness with sudden sleep attacks, hallucinations, and sleep paralysis.
- Parasomnia – abnormal behaviors or experiences while falling asleep, sleeping, or waking up.
- Periodic Limb Movement Disorder – repetitive, involuntary movements of the arms or legs during sleep.
- Restless Legs Syndrome – an overwhelming urge to move the legs, especially before sleep.
- Circadian Rhythm Sleep Disorders – disruptions in the body’s natural sleep-wake cycle.
- Sleep Apnea (Obstructive and Central Sleep Apnea) – breathing interruptions during sleep.
- Sleep Paralysis – temporary muscle paralysis before falling asleep or upon waking, often accompanied by hallucinations.
- Sleepwalking – performing activities like walking, eating, or talking while asleep.
- Sleep Phobia – fear of falling asleep, often linked to anxiety or panic attacks.
Top 5 Most Common Sleep Disorders
According to a 2018 Eastern European study, the top 5 most frequently reported sleep disorders are:
- Insomnia
- Narcolepsy
- Sleepwalking (Somnambulism)
- Night Terrors and Nightmares
- Snoring
1. Insomnia
Insomnia is a condition characterized by difficulty falling or staying asleep or experiencing poor-quality, restless sleep. It is classified into:
- Acute insomnia – lasts a few nights.
- Short-term insomnia – lasts up to 3 weeks.
- Chronic insomnia – lasts more than a month and is considered a disorder.
Symptoms of insomnia:
- Daytime sleepiness and fatigue.
- Poor concentration and memory issues.
- Mood disturbances, such as irritability or depression.
- Decreased performance at work or school.
2. Narcolepsy
Narcolepsy is a neurological disorder characterized by excessive daytime sleepiness and sudden, uncontrollable sleep attacks. It is often accompanied by:
- Sleep paralysis – temporary muscle paralysis upon waking or falling asleep.
- Cataplexy – sudden muscle weakness triggered by emotions.
- Hypnagogic hallucinations – vivid dream-like experiences.
Narcolepsy typically begins between ages 35 and 45 and affects 0.02% to 0.18% of the population, being more common in men.
3. Sleepwalking (Somnambulism)
Sleepwalking involves performing activities while asleep, such as:
- Sitting up in bed or walking around.
- Speaking or eating in sleep.
- Performing complex tasks like driving.
Sleepwalking affects 1% to 17% of the population and is more common in children. It may be triggered by fever, stress, or medication.
4. Night Terrors and Nightmares
Night terrors involve:
- Sudden awakening with extreme fear or panic.
- Screaming, sweating, and rapid heartbeat.
- Confusion and disorientation upon waking.
Night terrors affect 3% of children (ages 4–12) and 4–5% of adults, being more common in men.
Nightmares, on the other hand, involve frightening dreams that disrupt sleep and cause lingering anxiety upon waking.
5. Snoring
Snoring is a common breathing disorder during sleep caused by relaxed throat muscles obstructing airflow. It occurs in all sleep phases and is more prevalent in men (40%) than women (24%).
Symptoms of snoring:
- Loud, frequent snoring sounds.
- Morning headaches and dry throat.
- Daytime sleepiness due to poor sleep quality.
Treatment for Sleep Disorders
Depending on the type of sleep disorder, treatments include:
- Medications (sleep aids, antidepressants, or other prescriptions).
- Therapies, such as cognitive-behavioral therapy (CBT).
- Lifestyle changes, including proper sleep hygiene.
- Chronotherapy, adjusting sleep-wake cycles based on the body’s natural rhythms.
Preventing Sleep Disorders
To prevent sleep disorders, consider:
- Managing stress and anxiety effectively.
- Maintaining a balanced lifestyle with regular exercise.
- Prioritizing rest and relaxation.
- Establishing a consistent bedtime routine.
- Practicing good sleep hygiene.
