Nightmares and Bad Dreams

Nightmares can be defined as vivid and terrifying dreams which awaken the dreamer from sleep. Typically, the dreamer wakes from the REM stage of sleep and can remember a detailed, perhaps bizarre dream plot.^1,2

Although scary dreams are part of the normal human experience, for some they can be a recurrent and extremely troubling problem. This is particularly so for some young children. The DSM-IV diagnostic criteria for nightmare disorder are listed below:

Nightmares are common, particularly in children.

• Children:
  • 10–50% of those aged 3–6 yrs old are estimated to suffer from nightmares that disturb their sleep, or that of their parents.
  • This is the normal age for the experience of nightmares to begin.
  • The peak incidence of nightmare disorder occurs in this age group. Some studies found that up to 80% of young children experience 'scary dreams'.⁴
• Adults:
  • Estimates of adult prevalence of nightmares and troubling dreams are difficult to come by due to variable definitions and recall bias.
  • It is thought that the adult incidence of this disorder is low.

• Usually there is no underlying pathology.
• It is thought that recent traumatic events and psychological stress may contribute.
• Many medications are reported to increase nightmares:

• Nightmares tend to start in the latter half of the sleep cycle, during REM sleep.
• The nightmare usually involves a threat of danger. This may be a physical threat such as being pursued, or a psychological one such as being teased. Frequent threatening characters for children are monsters, ferocious animals, ghosts. bullies or 'bad' people.
• It is unusual for the person to shout out, move or have autonomic disturbance during the experience, though these things may occur to a minor degree.
• When awoken it is usual for the person to be oriented, alert and responsive and to be receptive to calming by their parents/others. The details of the dream are usually remembered. This contrasts with night terrors where the person may be difficult to rouse and may not recall what has been troubling them.
• There may be a family history of similar problems.

• Take a careful history, preferably also from parents, carers or relatives who have witnessed the event.
• Assess whether mental impairment, mental illness, depression, other CNS disease or a febrile illness could be contributing.
• Medication history and alcohol/benzodiazepine withdrawal.
• Any recent traumatic event or conflict/stress?

See related article Night Terrors and Parasomnias.

• Night terrors - the difference from nightmares are that: they tend to occur earlier rather than later during the night; the person may initially be unresponsive or disoriented; unlike nightmares, they usually cannot recall the event; signs of autonomic arousal such as dilated pupils, tachypnoea and tachycardia are more likely.
• Underlying organic brain disorder, e.g. delirium or mental impairment.
• Post-traumatic stress disorder (PTSD): nightmares are a feature of PTSD. However, in PTSD the dream content often involves reliving the trauma, and there are other symptoms such as poor sleep and daytime anxiety.
• Medication or withdrawal from medication
• Recurrent febrile illness causing delirium or predisposing to nightmares (this may also cause night terrors)
• Seizures
• Depressive illness with melancholic features may be associated in adults.⁷

Investigations are not usually necessary if the diagnosis is clear from the history. However, bear in mind that:

• Night terrors (sleep terrors) and sleepwalking (which differ from nightmares, as explained above) have been linked to physical sleep disorders such as obstructive sleep apnoea and other types of sleep disordered breathing.⁸ If these problems are suspected, or the diagnosis is unclear, assessment at a sleep clinic may help.⁹
• If there is reason to suspect an underlying cause then EEG, blood tests and CNS imaging may be considered.

• Reassurance of the patient or child and parents is all that is usually required.
• Helpful tips for children:
  • It may help to develop a relaxing bedtime routine that does not vary. Attention to causes of stress and upheaval within the home may help reduce the propensity to nightmares.
  • Use of night lights and other strategies that may reduce a child's anxiety levels at night, can help.
  • If the nightmare is recurrent then it may help for the parents to talk through the nightmare and imagine a less scary ending.
• If the problem is occurring, say, on a more than twice-weekly basis persistently, then it may be worth referring for psychological or child-psychiatric input. There is evidence that psychological techniques such as imagery rehearsal treatment may help.¹⁰
• Drug treatment is not usually helpful and is more likely to cause nightmares. (This contrasts with some other types of sleep disorder, where medication may help.)

Very good. The symptoms should resolve as time passes, and after reassurance of child and parents that this is a relatively normal experience for some young children.