(Also Known As: Dysomnia, Sleep Disorder, Anxiety, Sleep Problems, Sleeping Insomnia, Sleep Difficulty)

(Reviewed by: Paul Peterson, Licensed Therapist)

What is Dyssomnia?

Dyssomnia is a collective term given to a group of heterogeneous sleeping disorders that are characterized by disturbances in the body’s natural resting and waking patterns, disrupting the quantity, quality, or timing of sleep. Dyssomnia patients usually manifest difficulty in initiating or maintaining sleep or experience episodes of excessive daytime sleepiness known as somnolence. Along with Parasomnia, it is classified as one of the two main primary sleep disorders. Dyssmonia includes primary insomnia, Hypersomnia, Narcolepsy, Breathing Related Sleep Disorder, circadian rhythm sleep disorder (sleep-wake schedule disorder) and Dyssomnia NOS, or not otherwise specified. According to the International Classification of Sleep Disorders (ICSD), Dyssomnia is further divided into three broad categories based on pathology.

Three Sub-classifications of Dyssomnia:

  • Intrinsic Sleep Disorders – caused by physiological or pathological factors from within the body.
    • Psychophysiological Insomia or Conditional Insomnia - This condition demonstrates an inured arousal linked with attempts to sleep. Patients with psychophysiological insomnia incongruently induce wakefulness through items that are usually associated with sleep such as bed or bedroom. This often occurs together with other causes of insomnia, as well as periods of stress and anxiety conditions, delayed sleep phase syndrome, and hypnotic drug use withdrawal.
    • Sleep state misperception – This disorder is identified when a complaint of difficulty in initiating or maintaining sleep occurs with no actual indication of sleep disruption is established.
    • Idiopathic insomnia – As the name suggests, idiopathic insomnia has an unidentified cause; assumed causes comprise a neurochemical imbalance within the brainstem’s reticular formation and impaired control of brainstem sleep generators which arise from basal forebrain dysfunction. This pattern commonly initiates at birth and persists throughout life.
    • Narcolepsy – Narcolepsy originated from “narcolepsie”, a word which was created in 1880 by the French physician Jean-Baptiste-Édouard Gélineau. He combined the Greek word “narke”, meaning numbness or stupor and “lepsis”, meaning an attack or seizure. This chronic condition is most characterized by Excessive Daytime Sleepiness (EDS) and irregular Rapid Eye Movements (REM) sleep taking place daily for a period of 3 months. Narcoleptic patients suffer from extreme daytime drowsiness and sudden sleep attacks which takes place two to six times daily lasting from 10 to 20 minutes. These sleep attacks may occur unexpectedly while one is going about his daily activities. Another symptom that most narcoleptics feel is muscular weakness, or medically referred to as cataplexy, which range from scarcely discernible loosening of the facial muscles, to dropping of the jaw or head, shabbiness at the knees, or a total collapse. Frequently, speech is inaudible; vision is impaired; with occurrences of double vision and inability to focus the eyes onto an object and conversely, hearing abilities and awareness remain normal. In some atypical instances, an individual's body becomes paralyzed and muscles will become stiff and such may bring about total collapse.
    • Hypersomnia – This neurological condition refers to a set of related disorders that manifests somnolence or excessive daytime sleepiness. Most conditions of hypersomnia are hard to classify and idiopathic.
    • Primary hypersomnia – Primary hypersomnia, also referred to as idiopathic hypersomnia, is established when no other cause for excessive somnolence transpiring for at least 1 month can be found. When the condition manifest periods of excessive sleepiness that last for at least 3 days and occur several times a year within a period of 2 years, it would then be referred to as a recurrent hypersomnia.
    • Recurrent hypersomnia – Recurrent hypersomnia involves periods of excessive somnolence lasting for one or more days, recurring within a year or more. One of the most famous forms of recurrent hypersomnia is Kleine-Levin syndrome, which is a relatively rare condition comprising of recurrent periods of prolonged sleep, with intervening periods of normal sleep and alert awakening. Hypersomnia in most cases last for one week or more and are experienced by patients for over a year.
    • Sleep Apnea – The cessation of air flow at the nose or at the mouth during sleep is referred to as sleep apnea. By and large, an apneic period lasts 10 seconds or more. The condition is considered pathological if at least 5 apneic episodes occur within an hour or 30 apneic episodes during the night.
    • Obstructive sleep apnea syndrome – In pure obstructive sleep apnea, the air flow ceases but the respiratory effort amplifies. This pattern points toward an impediment in the airway and escalating efforts by the abdominal and thoracic muscles to compel clear of the obstruction.
    • Central alveolar hypoventilation syndrome – This state collectively refers to several conditions distinguished by impaired ventilation, all of which seriously worsens only during sleep and all through out, no significant apneic episodes are present.
    • Restless legs syndrome – In restless legs syndrome, persons feel deep sensations of creeping inside their calves whenever they are in a sitting or lying down position. These sensations are known as dyesthesias. Dyesthesias are seldom painful but are excruciatingly persistent causing a virtually tempting impulse to move the legs; consequently, this syndrome impedes with sleep and falling asleep.
  • Extrinsic Sleep Disorders – caused by environmental factors
    • Inadequate sleep hygiene – Sleep hygiene refers to nonspecific measures to induce sleep. In this syndrome, the sleeping habits are not able to provide the body a good sleep.
    • Altitude insomnia – A change in altitude causing a stress to the body leading to an inability to sleep or fall asleep.
    • Environmental sleep disorder – A change in environment causing a stress to the body leading to the inability to sleep or fall asleep.
    • Insufficient sleep syndrome – An intense complaint of daytime sleepiness and associated waking symptoms by a person who unrelentingly fail to acquire ample daily sleep to support alert wakefulness, is referred to as insufficient sleep syndrome. The person is usually sleep-deprived out of his own will, which may be due to various reasons like work or study.
    • Food allergy insomnia – Intake of certain foods causing allergic reactions in the form of insomnia
    • Adjustment sleep disorder
    • Limit-setting sleep disorder
    • Sleep-onset association disorder
    • Nocturnal eating/drinking syndrome
    • Hypnotic-dependent sleep disorder
    • Stimulant-dependent sleep disorder
    • Alcohol-dependent sleep disorder
    • Toxin-induced sleep disorder
    • Extrinsic sleep disorder NOS
    • Circadian Rhythm Sleep Disorders – This is mainly caused by a change in a person’s biological rhythm or internal clock known as the Circadian rhythm. Plants, animals and humans all possess a biological rhythm or bio-rhythm. This mainly controls body temperature, alertness or wakefulness, appetite, hormone secretion as well as sleep timing. Due to the circadian clock, sleepiness does not incessantly increase as time passes. A person's desire and ability to fall asleep is influenced by both the length of time since the person woke from an adequate sleep (homeostasis), and by internal circadian rhythms. Thus, the body is ready for sleep and for wakefulness at different times of the day. 1

Circadian rhythm sleep disorders are a group of disorders affecting the normal timing of sleep. People with these conditions are unable to sleep and wake at the times required for normal work, school, and social needs. They are generally able to get enough sleep only if allowed to sleep and wake at the times imposed by their body clocks. Unless there is another underlying sleep disorder, the quality of their sleep is considered normal.

Types of Circadian Rhythm Syndromes

  • Time zone change (jet lag) syndrome
  • Shift work sleep disorder
  • Irregular sleep-wake pattern
  • Delayed sleep phase syndrome
  • Advanced sleep phase syndrome
  • Non-24 hour sleep-wake disorder
  • Circadian rhythm sleep disorder NOS

Could You Have Dyssomnia?

Dyssomnia Topics

Related Conditions

Hypersomnia – Recurrent Episodes of Daytime Sleepiness, Insomnia, Sleep Disorder, Excessive Sleepiness
Narcolepsy – Chronic Sleep Disorder, Excessive Daytime Sleepiness, Insomnia, Inability to Sleep
Parasomnia NOS – Arousal Disorders, Sleep-Wake Transition Disorders, Parasomnias Usually Associated with REM Sleep
Primary Sleep Disorder – Impaired Sleep Wake Cycles, Hypersomnia, Excessive Daytime Sleepiness, Inability to Sleep