Insomnia: what it is and how it differs from insomnia disorder

The night passes and sleep still does not come: a person tosses and turns, looks at the clock, and by morning feels drained. In such a situation people usually say "insomnia," although doctors also use another word — insomnia disorder. Let us clarify what this term means and when poor sleep stops being merely an annoyance.

What insomnia and insomnia disorder are

Insomnia, also known as insomnia disorder (from the Latin in- — "not" and somnus — "sleep"), is a sleep disorder in which its duration or quality does not satisfy the person over a noticeable period of time. The term also has rarer names — asomnia and agrypnia. Insomnia and insomnia disorder are the same sleep disorder. Insomnia belongs to the dyssomnias — a group of sleep disorders. The absolute number of hours of sleep is not decisive here: the norm varies greatly between people. On average, adults need 7–9 hours, children 9–13, and young children and infants 12–17. Constant fatigue during the day is a better indicator of insufficient sleep.

How insomnia manifests

The manifestations are familiar to almost everyone: a person cannot fall asleep for a long time or wakes up at night, and in the morning gets up without strength. Doctors describe this as presomnic, intrasomnic, and postsomnic disturbances — difficulties before sleep, during sleep, and after waking.

• taking a long time to fall asleep
• frequent awakenings at night, after which it is hard to fall asleep again
• early awakening and inability to fall asleep again
• a feeling of light, non-restorative sleep
• fatigue, irritability, and difficulty concentrating during the day

One bad night is not enough for a diagnosis. The complaints recur at least three times a week for a month, the person is worried about sleep and its consequences, and this noticeably interferes with daytime life.

Acute and chronic insomnia

Short-term, or acute, insomnia lasts days or weeks, or by another scale — less than three months. If the disturbances persist for three months or longer, it is called chronic, or long-term, insomnia; in some formulations the count starts from one month. The acute form is often triggered by stress at work, family difficulties, or a severe event. The chronic form is more often secondary — a symptom or side effect of another disease, medications, substances, or other sleep disorders. Less often it acts as an independent problem, and its causes are less well studied. Anxiety about sleep itself contributes to chronification: the person fears not falling asleep, and the bedroom setting begins to trigger excessive brain activation. Such insomnia is called psychophysiological.

Sudden insomnia: what may be behind it

When sleep is disturbed unexpectedly, the causes are most often the same as those of acute insomnia. Among the causes of insomnia are stress, anxiety or depression, noise, a room that is too hot or too cold, an uncomfortable bed, alcohol, caffeine and nicotine, some drugs, jet lag, and shift work. Sometimes the cause is another condition or medication: insomnia can be caused by mental disorders, Alzheimer's and Parkinson's disease, restless legs syndrome, an overactive thyroid, menopause, chronic pain, snoring and sleep apnea, narcolepsy, and nightmares. There is also a rare hereditary disease — fatal familial insomnia. A doctor helps determine what exactly triggered it.

What health risks insomnia poses

The consequences affect primarily daytime life: drowsiness, lack of energy, anxiety, low mood and irritability, difficulties with attention, learning, and memory. A separate risk is drowsiness while driving, which increases the likelihood of an accident. The link between insomnia and depression and anxiety disorders is complex and bidirectional: poor sleep can be their symptom, and it can also be a factor that pushes toward the development of a depressive episode.

When insomnia requires a doctor's consultation

The reason to see a doctor is if changes in sleep habits have not helped, if sleep difficulties persist for months, and if insomnia affects daytime life so much that coping becomes difficult. The doctor asks about sleep history and health, performs an examination, and if necessary orders laboratory tests, a sleep diary, and polysomnography. If there are signs of another sleep disorder, such as apnea, the person is referred to a sleep laboratory. Cognitive behavioral therapy is also discussed: it helps change the thoughts and behaviors that interfere with sleep.

Insomnia by itself is not a reason to call an ambulance. The numbers 103 and 112 are for life-threatening conditions, for example signs of stroke or heart attack.

This material is for reference and does not replace a doctor's consultation.

This content is for reference and does not replace a doctor's consultation. Medical disclaimer