Dyssomnien

Dyssomnien is a collective term used in sleep medicine to refer to disorders that involve problems with the amount, quality, or timing of sleep. They are categorized separately from parasomnias, which involve abnormal events during sleep, such as sleepwalking or nightmares. Dyssomnien can be primary (not explained by another condition) or secondary to medical, psychiatric, or substance-related factors.

The main subtypes are insomnia disorders, hypersomnia disorders, and circadian rhythm sleep-wake disorders. Insomnia disorders involve difficulty initiating sleep, maintaining sleep, or experiencing non-restorative sleep, lasting long enough to cause daytime impairment. Hypersomnia disorders are characterized by excessive daytime sleepiness or prolonged nighttime sleep that is not restorative. Circadian rhythm sleep-wake disorders arise from a misalignment between the internal circadian clock and environmental demands, leading to shifted sleep times, jet lag, or irregular sleep schedules.

Causes are multifactorial and may include primary sleep susceptibility, medical or mental health conditions, medications, substance use, and environmental factors such as stress or irregular work hours. Risk factors include older age, female sex in some conditions, shift work, and high stress.

Diagnosis relies on clinical history, sleep diaries, and, when appropriate, actigraphy or polysomnography. Classification follows standardized criteria in manuals such as the ICSD-3. Treatment emphasizes non-pharmacologic approaches first, notably cognitive behavioral therapy for insomnia (CBT-I) and sleep-hygiene education. Pharmacologic options may be considered short-term for some patients. For circadian disorders, light therapy and melatonin are commonly used. Addressing comorbid conditions and optimizing sleep schedules are essential for improving outcomes.