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

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, both groups declined significantly in overall dysfunctional sleep beliefs from pre- to post-intervention (both p< .04); however, they did not differ on sleep-related beliefs nor pre-sleep cognitions and arousal at post-intervention (both p> .50). Dysfunctional beliefs sleep expectations subscale was lower in CBT-I+Light versus TAU+ (p= .01). Behaviorally, CBT-I+Light reported less overall time in bed awake after the start of the intervention (p< .05) and significantly less time in bed during the morning until the final week of the intervention period. Out-of-bedtime day-to-day variability was lower in the CBT-+Light vs TAU+ at the final intervention day. CONCLUSION: Mechanisms of CBT-I+Light during chemotherapy remain to be shown. Our results suggest that changes in behavioral mechanisms may be associated with sleep improvements within this cohort. Future studies should assess the role of additional mechanisms (e.g., sleep effort) within larger samples. Whilst intervention brevity is important, more potent interventions may be required to achieve robust changes in target mechanisms.

The Sleep, Cancer and Rest (SleepCaRe) Trial: Rationale and design of a randomized, controlled trial of cognitive behavioral and bright light therapy for insomnia and fatigue in women with breast cancer receiving chemotherapy.

BACKGROUND: Insomnia and fatigue symptoms are common in breast cancer. Active cancer treatment, such as chemotherapy, appears to be particularly disruptive to sleep. Yet, sleep complaints often go unrecognised and under treated within routine cancer care. The abbreviated delivery of cognitive behavioral therapy for Insomnia (CBTI) and bright light therapy (BLT) may offer accessible and cost-effective sleep treatments in women receiving chemotherapy for breast cancer. METHODS: The Sleep, Cancer and Rest (SleepCaRe) Trial is a 6-month multicentre, randomized, controlled, 2 × 2 factorial, superiority, parallel group trial. Women receiving cytotoxic chemotherapy for breast cancer at tertiary Australian hospitals will be randomly assigned 1:1:1:1 to one of four, non-pharmacological sleep interventions: (a) Sleep Hygiene and Education (SHE); (b) CBTI; (c) BLT; (d) CBT-I + BLT combined and simultaneously delivered. Each sleep intervention is delivered over 6 weeks, and will comprise an introductory session, a mid-point phone call, and regular emails. The primary (insomnia, fatigue) and secondary (health-related quality of life, rest activity rhythms, sleep-related impairment) outcomes will be assessed via online questionnaires at five time-points: baseline (t0, prior to intervention), mid-point intervention (t2, Week 4), post-intervention (t3, Week 7), 3-months (t4, Week 18), and 6-months follow-up (t5, Week 30). CONCLUSIONS: This study will report novel data concerning the comparative and combined efficacy of CBT-I and BLT during chemotherapy. Findings will contribute to the development of evidence-based early sleep and fatigue intervention during chemotherapy for breast cancer. Clinical trial information Registered with the Australian New Zealand Clinical Trials Registry (http://anzctr.org.au/), Registration Number: ACTRN12620001133921.