Mechanisms of Cognitive Behavioral Therapy and Light Therapy for Cancer-Related Insomnia: A Randomized Clinical Trial during Chemotherapy for Breast Cancer

Abstract

Study Objectives: This study aimed to investigate the mechanisms of a combined brief cognitive behavioral plus bright light therapy (CBT-I+Light) in women receiving chemotherapy. Methods: Women (N = 101) were randomly assigned to CBT-I+Light or treatment as usual plus relaxation audios (TAU+). Participants completed sleep diaries and wore an actigraph during the 6-week intervention period. Patient-reported outcomes were assessed at baseline, mid-point (week 3), and later (week 6). Cognitive (i.e., dysfunctional sleep beliefs, pre-sleep cognitions, and arousal) and behavioral (i.e., time in bed awake and day-to-day out-of-bedtime variability) mechanisms were examined. Results: Cognitively, bo..