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 validity of the pupillographic sleepiness test at shorter task durations.

The pupillographic sleepiness test (PST) is an accurate predictor of alertness failure and performance impairment across sleep deprivation. At 11 min in duration, the task is considered too long to be used in occupational or roadside settings. We therefore investigated the predictive capacity of the PST at seven shortened test durations. Eighteen healthy young adults (aged 21.4 ± 3.2 years, 10 men) underwent 40 h of continuous wakefulness, completing an 11-min PST and a 10-min psychomotor vigilance task (PVT) every 2 h. Waking electroencephalography was recorded and scored for microsleeps during PVTs. The PST was divided into eight equal 82-s blocks and the predictive capacity of the pupillary unrest index (PUI) calculated at descending PST durations by systematically removing blocks. PUI increased significantly with time awake for all test durations (p < .0001), with a similar amplitude of PUI observed for test durations of 5.5 min and longer. While all test durations accurately predicted PVT impairment (AUC: 0.72-0.86, p < .001) and microsleep (AUC: 0.74-0.84, p < .0001), 5.5 min was the shortest duration where accuracy remained high across level and type of impairment (AUC: 0.79-0.86). For the 5.5-min duration, the positive predictive value (PPV) and negative predictive value (NPV) were on average 50.1% and 89.4%, respectively, and were comparable to the full 11-min task (PPV: 49.2%; NPV: 91%). The PST can be shortened to 5.5 min without compromising accuracy in detecting performance impairment or physiological drowsiness. The PST is an ideal candidate for fitness-for-duty or fitness-to-drive testing, and future studies should examine its predictive capacity, at shorter durations, against operationally relevant outcomes.

Pupillary instability as an accurate, objective marker of alertness failure and performance impairment.

Pupillary instability reflects alterations in autonomic nervous system activity and has been shown to reflect change in alertness. However, the extent to which it can predict subsequent performance impairment and alertness failure is not clear. Eighteen healthy young adults (group age = 21.44 ± 3.24 years, 10 men) underwent 40 hr of continuous wakefulness, completing an 11-min Pupillographic Sleepiness Test (PST), the Karolinska Sleepiness Scale and a 10-min Psychomotor Vigilance Task (PVT) every 2 hr. Waking electroencephalography was recorded continuously and scored for microsleeps and slow eye movements (SEMs) during PVTs. Pupillary instability was sensitive to time awake, significantly increasing after 18 hr of wakefulness. The time course of impairment was almost identical to PVT lapses, microsleeps and SEMs. Receiver operating characteristic curve analysis demonstrated reasonable sensitivity and specificity of pupillary instability in correctly classifying PVT lapses, microsleeps and SEMs above individual baseline thresholds (all AUC values >0.78, p < 0.0001). Preliminary cut-off scores ranging from 10 to 11.5 mm/min for varying impairment thresholds are proposed for young adults. If reproducible in field settings, the PST may be a strong candidate as a fitness for duty/fitness to drive tool for detecting drowsiness-related impairment.

Feasibility and efficacy of 'Can-Sleep': effects of a stepped-care approach to cognitive-behavioral therapy for insomnia in cancer.

PURPOSE: This study aimed to evaluate the feasibility and clinical efficacy of the Can-Sleep stepped-care intervention for people with cancer-related sleep disturbance. METHODS: A total of 147 individuals with cancer were screened. Participants who reported sleep disturbances and were at low-moderate risk for intrinsic sleep abnormalities were given self-managed cognitive behavioral therapy for insomnia (SMCBT-I). Those reporting sleep disturbance and scoring at high risk of intrinsic sleep abnormalities (i.e., restless leg syndrome and obstructive sleep apnoea) were referred to a specialist sleep clinic. In both groups, participants received a stepped-up group CBT-I intervention (GCBT-I) if they continued to report sleep disturbance following SMCBT-I or the specialist sleep clinic. RESULTS: Overall, 87 participants reported sleep disturbance or screened at risk for intrinsic sleep abnormality. Thirty-four were referred to a specialist sleep clinic, and of the 17 who declined this referral, 14 were rereferred to SMCBT-I. In total, 62 participants were referred to SMCBT-I, and 56 commenced SMCBT-I. At post-intervention, the SMCBT-I group showed a significant decline in insomnia symptoms (p < .001, d = 1.01). Five participants who reported sleep disturbance after SMCBT-I and/or the specialist sleep clinic, accepted GCBT-I. Those who received the GCBT-I showed a significant reduction in insomnia symptoms (p < .01, d = 3.13). CONCLUSIONS: This study demonstrates the feasibility and efficacy of a stepped-care intervention for sleep disturbances in people with cancer. IMPLICATIONS FOR CANCER SURVIVORS: A stepped-care intervention for sleep disturbance is a feasible and potentially effective method of addressing a significant and unmet patient need.

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.