Nightmares : Assessment, theory, and treatment

Abstract

Nightmares tend to occur less often in a sleep laboratory. To test this, twelve PTSD-inpatients suffering from posttraumatic nightmares kept a diary and filled out a questionnaire considering their sleep and nightmares. Polysomnographic sleep-data were recorded in the clinic for two consecutive 24-hour periods. Significantly fewer than expected nightmares were recorded with polysomnography. The short duration questionnaire correlated very highly with the diary and seems to be the method of choice for assessing nightmare frequency.

Therefore the SLEEP-50 questionnaire, designed to detect sleep disorders as listed in the DSM-IV-TR, was evaluated in a sample of 377 college students, 246 sleep patients, 32 nightmare sufferers, and 44 healthy volunteers. The internal consistency was high; test-retest correlations were good, and the factor-structure closely matched the designed structure. Sensitivity/specificity scores were promising for all sleep disorders; the agreement between all clinical diagnoses and SLEEP-50-classifications was substantial (kappa = .77), indicating the SLEEP-50 can detect a variety of sleep disorders.

The SLEEP-50 was then used to investigate the prevalence of sleep disorders and its relations with affective complaints in a non-clinical population. Eight-hundred randomly selected adult persons received the SLEEP-50 and two psychiatric questionnaires. Four-hundred-and-two filled out these questionnaires completely. Forty-one percent reported sleep complaints, 23.5% had a sleep disorder, and 2.7% had two sleep disorders. Prevalences were: insomnia: 8.5%, restless legs: 5.2%, sleep apnea: 4.0%, nightmares: 2.2%, circadian rhythm sleep disorder: 1.7%, hypersomnia: 1.2%, and narcolepsy: 0.7%. Results showed a high interrelatedness between sleep and mental complaints.

In addition, the current debate focuses on the DSM-IV-TR definition of nightmares, of which direct awakening from a disturbing dream is a criterion. Forthy-eight nightmare sufferers filled out questionnaires regarding their nightmares, sleep, and mental complaints. Direct awakening was not related to any mental complaint or general psychopathology with the exception of agoraphobia. Only 22.9 percent reported to always wake up from a nightmare. The DSM-IV definition of nightmares needs to be refined.

Two pilots were conducted to evaluate the effects of the cognitive-restructuring technique lucid dreaming treatment (LDT) on chronic nightmares. Becoming lucid (realizing that one is dreaming) in a nightmare allows persons to alter the nightmare-storyline in the nightmare itself. LDT consists of exposure, mastery, and lucidity exercises.

First, eight participants received a one-hour individual session after filling out the SLEEP-50 and the Spielberger State and Trait Anxiety Inventory. Two months later the nightmare frequency had decreased, while the sleep quality had increased slightly. There were no changes on state and trait anxiety.

Second, twenty-three nightmare sufferers were randomized (after having filled out the SLEEP-50 and a PTSD-questionnaire) into; one individual session (8), one group session (8), and a waiting-list (7). The same questionnaires were filled out twelve weeks later; the nightmare frequency of both treatment groups had decreased. Lucidity was not necessary for a reduction in nightmare frequency. Addressing that a change in the nightmare-storyline is possible may be the key-component of this technique; recurrent nightmares seem to be represented in a script. A cognitive model of nightmares is described in this dissertation.