Everyone experiences bad dreams or nightmares. But for some people nightmares are a part of sleep they cannot escape. When nightmares become a consistent part of sleep, it escalates to a disorder. Nightmares are not the only frightening sleep disturbances; fright in the night can also include sleep terrors. Understanding nightmare disorders and sleep terrors may help those struggling to sleep.
What are Nightmare Disorders
Nightmare disorder is the repeated occurrence of nightmares that are well-remembered, realistic, vivid, and highly disturbing. They often leave a person feeling uneasy and distressed. Nightmares can be so frightening that they cause awakenings with significant distress. This can lead to mood disturbances or a fear of sleep. People may avoid sleep because they fear a recurrence or continuation of the nightmare. Furthermore, these nightmares are clearly recalled which contribute to distress and fear of sleep.
Who is at Risk for Nightmare Disorders?
Nightmares are particularly frequent in children, but they typically resolve on their own and do not cause persistent distress or lasting effects. However, children exposed to psychosocial stressors are more likely to experience nightmare disorders. Psychosocial stressors are major life events that require dramatic adjustments such as moving or divorce.
People with high levels of anxiety or Post Traumatic Stress Disorder (PTSD) are at risk for nightmare disorders. PTSD may cause realistic dreams where the person re-lives traumatic events and becomes emotionally engaged.
Nightmare disorders may also be related to sleep apnea. Often these dreams relate to respiratory difficulties such as suffocating or drowning. Some antidepressants, antihypertensives, and melatonin have also been associated with an increased risk of nightmare disorders.
Associated Disturbances
Nightmares as part of a nightmare disorder disturb sleep and can lead to awakenings causing sleep fragmentation. The results may include daytime sleepiness, low energy, and daytime anxiety. The fear of nightmares can cause anxiety over falling asleep which may lead to the development of insomnia.
Sleep Terrors
Nightmare disorders are different from sleep terrors. With sleep terrors dreams often are not fully remembered, only pieces. Also, sleep terrors are associated with increased heartrate, respiratory rate, skin flushing, excessive sweating, pupil dilation, and increased muscle tone. None of these physical effects are present in nightmare disorders. Nightmares occur during rapid eye movement (REM) sleep, during the second half of sleep. Sleep terrors occur during non-REM (NREM) sleep, usually during the first half of sleep. Sleep terrors are part of the arousal disorders spectrum. Even though the person’s eyes may be open during the sleep terror, they will have little memory of the event. Because the dream is not remembered it doesn’t cause anxiety around future sleep.
Treatments
Usually, nightmares do not require treatment. If you are experiencing a nightmare disorder, a useful approach may be imagery rehearsal therapy, which can be practiced with specialists. This includes consciously changing the end of the nightmare and rehearsing a more favorable ending while awake. The result should be a dream that is no longer threatening or fearful.
Though medications may help treat nightmare disorders, their effects are not consistent. Sleep doctors have found that individual responses to medications vary.
Professional treatment for nightmare disorders is recommended when it interferes with daytime activities or if there is a known cause such as PTSD. In these instances, consult a sleep professional. If nightmares produce repetitive behaviors, or pose a risk of injury, asleep study is recommended. This can help to rule out other parasomnias or seizures.
It is possible that what seems like a nightmare disorder may reflect the onset of REM-behavior disorder. So, it is important to determine if parts of the nightmare are acted out.
Conclusion
Nightmare disorders and night terrors can have a significant impact on your sleep. If you struggle with nightmare disorder or sleep terrors, seek out a sleep specialist to improve your sleep.
Ambra Stefani, MD, PhD, is a Neurologist at the Medical University of Innsbruck, Austria, specializing in sleep medicine. Her research career has focused on sleep related movement disorders, parasomnias, and sleep and neurodegeneration.