Investigating racing thoughts in insomnia: A neglected piece of the mood-sleep puzzle?

• Main Authors: Luisa Weiner, Emilie Martz, Ülker Kilic-Huck, Nathalie Siegel, Gilles Bertschy, Pierre A. Geoffroy, Sébastien Weibel, Patrice Bourgin
• Format: Article
• Language: English
• Published: Elsevier 2021-11-01
• Series: Comprehensive Psychiatry
• Subjects: insomnia disorder; racing thoughts; rumination; worry; arousal; emotion dysregulation
• Online Access: http://www.sciencedirect.com/science/article/pii/S0010440X21000493

Background: Cognitive arousal is thought to play a key role in insomnia disorder. However, although patients frequently complain about racing thoughts appearing at bedtime, studies have considered ‘cognitive arousal’ as a synonym of rumination and worry, but not as racing thoughts per se. The latter have been mainly linked to hypomanic/manic episodes of bipolar disorder (BD). Here we aimed at investigating self-reported racing thoughts in insomnia disorder, and their specific contribution to insomnia severity, as compared to worry and rumination. Methods: 72 adults with insomnia disorder, 49 patients with BD in a hypomanic episode and 99 healthy individuals completed the Racing and Crowded Thoughts Questionnaire (RCTQ). Mood symptoms were assessed in patients with insomnia disorder. Results: RCTQ scores were overall higher in insomnia disorder, especially in sleep-onset insomnia, compared to the hypomanic and healthy groups. Moreover, racing thoughts showed an increase in the evening and at bedtime in sleep-onset insomnia. Importantly, racing thoughts at bedtime, but not rumination and worry, were associated with insomnia severity. Discussion: Our results are the first to show that racing thoughts is a transdiagnostic symptom in mood and sleep disorders. Racing thoughts, not only rumination and worry, might contribute to the maintenance of sleep difficulties in insomnia.Clinical trials' registration number: NCT04752254