Night-time rumination in PTSD: development and validation of a brief measure.

Background

Pre-sleep cognitive activity and arousal have long been implicated in the maintenance of insomnia. However, despite high comorbidity between insomnia and posttraumatic stress disorder (PTSD), pre-sleep thoughts in PTSD and their associations with disturbed sleep, have not yet been investigated.

Objective

This study presents the development and preliminary validation of a brief self-report measure of the content of trauma-related pre-sleep thoughts: the Trauma Thoughts before Sleep Inventory (TTSI).

Methods

Participants (N = 285) were recruited online into five groups: three groups with clinical symptoms, 1) PTSD; 2) depression without PTSD; 3) insomnia without depression or PTSD; and two healthy control groups 4) nontrauma-exposed controls; 5) trauma-exposed controls. The questionnaire was administered at baseline, and for a subsample (n = 157) again one week later to assess test-retest reliability. At baseline, participants also completed questionnaires of sleep quality, PTSD and depression symptoms, and insomnia-related thoughts.

Results

The TTSI had good reliability and validity; it discriminated participants with PTSD from those with depression and insomnia, those with depression from insomnia, and correlated with existing measures of pre-sleep thoughts, self-reported pre-sleep arousal and poor sleep.

Conclusions

The results support the utility of the TTSI for measuring thoughts that keep people with PTSD awake, although replication in an independent clinical sample is required.