Mediators of cognitive-behavioral therapy for insomnia: A review of randomized controlled trials and secondary analysis studies

An exploration into the relationship between insomnia and repetitive negative thinking among cancer survivors

OBJECTIVE

Insomnia and repetitive negative thinking (RNT) are both prevalent among cancer survivors, yet little work has investigated their interrelationship. To explore the hypothesis that RNT and insomnia are related, we conducted secondary analyses on data from a pilot clinical trial of cognitive behavioral therapy for insomnia (CBT-I) for cancer survivors.

METHODS

This study analyzed survey data from 40 cancer survivors with insomnia who participated in a pilot randomized trial of CBT-I. Correlations and linear regression models were used to determine associations between aspects of RNT and related constructs (fear of cancer recurrence [FCR], cancer-specific rumination, worry, and intolerance of uncertainty) and sleep (insomnia and sleep quality), while accounting for psychiatric symptoms such as anxiety and depression. Treatment-related change in RNT was examined using a series of linear mixed models.

RESULTS

Evidence for an association between RNT and insomnia among cancer survivors emerged. Higher levels of FCR and cancer-related rumination were correlated with more severe insomnia symptoms and worse sleep quality. Notably, FCR levels predicted insomnia, even after controlling for anxiety and depression. Results identified potential benefits and limitations of CBT-I in addressing RNT that should be examined more thoroughly in future research.

CONCLUSIONS

RNT is a potential target to consider in insomnia treatment for cancer survivors.

Do changes in beliefs and behaviours moderate improvement in insomnia after acquired brain injury?

Key mechanisms of change in cognitive behavioural therapy for insomnia in the general population encompass changing sleep-related beliefs and behaviours. In a population with acquired brain injury, cognitive behavioural therapy for insomnia is effective as well, but little is known about the mechanisms of change. The aim of this study was to evaluate how changing sleep-related beliefs and behaviours were associated with improvement in insomnia following blended cognitive behavioural therapy for insomnia in a population with acquired brain injury. A secondary analysis was performed on data of a randomized-controlled trial, including 24 participants that received blended cognitive behavioural therapy for insomnia, and 24 participants that received treatment as usual. Results showed that following blended cognitive behavioural therapy for insomnia, significantly more participants improved on dysfunctional beliefs and sleep-related behaviours and this was associated to improvement in insomnia severity. For sleep-related behaviours, the association between improvement on behaviour and improvement on insomnia was significantly moderated by blended cognitive behavioural therapy for insomnia. However, the relation between dysfunctional beliefs and insomnia was not moderated by type of treatment. Similar results were found for acquired brain injury-adapted versions of the questionnaires in which up to half of the items were excluded as they could be regarded as not dysfunctional for people with acquired brain injury. These results show that improvement on insomnia severity is related to improvement in dysfunctional beliefs and behaviours, and cognitive behavioural therapy for insomnia efficacy may be moderated by the improvement in behaviours in particular. A focus on these behaviours can enhance treatment efficacy, but caution is needed regarding the behaviours that may reflect adequate coping with the consequences of the acquired brain injury.

Changes in sleep effort mediate insomnia severity in older adults following online cognitive behavioural therapy

BACKGROUND

To examine treatment mechanisms of digitally delivered cognitive behavioural therapy for insomnia (CBT-I), this study assessed the mediating effects of dysfunctional beliefs, hyperarousal, locus of control, self-efficacy, sleep effort, and safety behaviours on self-reported insomnia severity in older adults before and following the completion of a self-guided, online CBT-I program.

METHODS

The baseline and follow-up measurements were completed by 62 older adults (55 female, 89%). This was a two-condition within-participant design. Mediation analysis using a parallel mediation model was conducted using the MEMORE macro for repeated measure designs.

RESULTS

Out of all the included mediator variables, only a reduction in sleep effort scores (0.88; SE 0.51; 95% CI 0.001-2.00) significantly mediated changes in insomnia severity scores following the intervention. Insomnia severity scores significantly reduced following the intervention (Mpre  = 9.84, SD = 5.89, Mpost  = 6.87, SD = 4.90); t(61) = 5.19, P = <0.001; d = 0.55 95% CI 0.38-0.93.

CONCLUSIONS

Sleep in older adults improved following digitally delivered CBT-I, and these changes were influenced by a reduction in sleep control efforts exerted by participants. These findings highlight possible treatment pathways of CBT-I. Further investigation of CBT-I as a strategy to prevent sleep problems is warranted.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry (ANZCTR), ACTRN 12619001509156; http://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=378451.

Psychosocial factors of insomnia in depression: a network approach

BACKGROUND

Insomnia symptoms in patients with major depressive disorder (MDD) are common and deleterious. Childhood trauma, personality traits, interpersonal distress, and social support contribute to insomnia, but how they interact to affect insomnia remains uncertain.

METHODS

A total of 791 patients with MDD completed the Insomnia Severity Index, Eysenck Personality Questionnaire, Interpersonal Relationship Comprehensive Diagnostic Scale, Childhood Trauma Questionnaire, Social Support Rating Scale and Hamilton Depression Scale-17. This study utilized network analyses to identify the central symptoms of insomnia and their associations with psychosocial factors.

RESULTS

Worrying about sleep was identified as the central symptom in the insomnia network, insomnia and associated personality network, insomnia and associated interpersonal disturbance network, insomnia and associated childhood trauma network, insomnia and associated social support network, and the integrated network of insomnia symptoms and associated psychosocial factors. In the networks of insomnia symptoms and individual psychosocial factors, most psychosocial factors (other than childhood trauma) were directly or indirectly related to insomnia symptoms; however, neuroticism was the only factor directly associated with insomnia symptoms before and after controlling for covariates. In the final integrated network of insomnia symptoms and psychosocial factors, neuroticism was a bridge node and mediated the relationships of social support and interpersonal disturbances with insomnia symptoms, which is clearly presented in the shortest pathways.

CONCLUSIONS

Worrying about sleep and neuroticism were prominent in the integrated network of insomnia symptoms and associated psychosocial factors, and the edge between them connected psychosocial factors and insomnia symptoms in MDD patients.

Mechanisms of cognitive behavioural therapy for insomnia

Although much is known now about behavioural, cognitive and physiological consequences of insomnia, little is known about changes after cognitive behavioural therapy for insomnia on these particular factors. We here report baseline findings on each of these factors in insomnia, after which we address findings on their changes after cognitive behavioural therapy. Sleep restriction remains the strongest determinant of insomnia treatment success. Cognitive interventions addressing dysfunctional beliefs and attitudes about sleep, sleep-related selective attention, worry and rumination further drive effectiveness of cognitive behavioural therapy for insomnia. Future studies should focus on physiological changes after cognitive behavioural therapy for insomnia, such as changes in hyperarousal and brain activity, as literature on these changes is sparse. We introduce a detailed clinical research agenda on how to address this topic.

Challenging beliefs for quality sleep: A systematic review of maladaptive sleep beliefs and treatment outcomes following cognitive behavioral therapy for insomnia

Cognitive behavioral therapy for insomnia (CBT-I) is an empirically supported intervention for insomnia. Given the strong, consistent support of its efficacy, scholars have become increasingly interested in the behavioral and cognitive mechanisms targeted during CBT-I. The purpose of the systematic review was to synthesize findings from the literature regarding the associations among maladaptive sleep beliefs, a cognitive mechanism implicated in maintaining insomnia, and treatment outcomes following CBT-I. The systematic review was completed using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Seventeen studies were included in the final sample of reviewed articles and a study quality assessment was performed for all studies included in the review. The results suggested that reductions in maladaptive sleep beliefs were associated with improved insomnia severity; however, reductions in maladaptive beliefs were not associated with changes in sleep efficiency or other sleep parameters. Moreover, in some cases, improved sleep parameters preceded reductions in maladaptive beliefs. Maladaptive sleep beliefs may be an important target for improving insomnia. Targeting maladaptive sleep beliefs may initiate a trickle-down process that limits the influence of other cognitive and behavioral processes maintaining insomnia. Additional investigation is needed to evaluate the directional relationship between improved insomnia symptoms and reduced maladaptive beliefs.

Insomnia severity and its correlates among English as a second language (ESL) college students

OBJECTIVE

Little is known about insomnia characteristics among the English as a second language (ESL) student population. This study compared insomnia severity between ESL students and English native-speaking students and identified correlates of insomnia in the ESL population.

PARTICIPANTS

College students (N = 352) from a private university in the Northeastern United States, including 22.4% (N = 79) ESL students.

METHODS

For this cross-sectional study, participants completed the Insomnia Severity Index and indices of common risk factors of insomnia along with acculturation and language anxiety.

RESULTS

ESL students reported higher insomnia severity than their US counterparts after controlling for depression, anxiety, and demographics. General anxiety, language anxiety, and cognitive pre-sleep arousal were selected as the strongest predictors of insomnia among the ESL population.

CONCLUSIONS

Findings suggest that ESL college group is vulnerable to greater insomnia, and language anxiety is unique and important correlate of insomnia in this population.

Reducing cognitive arousal and sleep effort alleviates insomnia and depression in pregnant women with DSM-5 insomnia disorder treated with a mindfulness sleep program

Objectives

Combining mindfulness with behavioral sleep strategies has been found to alleviate symptoms of insomnia and depression during pregnancy, but mechanisms for this treatment approach remain unclear. The present study examined nocturnal cognitive arousal and sleep effort as potential treatment mechanisms for alleviating insomnia and depression via a mindfulness sleep program for pregnant women.

Methods

Secondary analysis from a proof-of-concept trial of 12 pregnant women with DSM-5 insomnia disorder who were treated with Perinatal Understanding of Mindful Awareness for Sleep (PUMAS), which places behavioral sleep strategies within a mindfulness framework. Data were collected across eight weekly assessments: pretreatment, six sessions, and posttreatment. Measures included the insomnia severity index (ISI), Edinburgh postnatal depression scale (EPDS), pre-sleep arousal scale's cognitive factor (PSASC), and the Glasgow sleep effort scale (GSES). We used linear mixed modeling to test cognitive arousal and sleep effort as concurrent and prospective predictors of insomnia and depression.

Results

Most patients reported high cognitive arousal before PUMAS (75.0%), which decreased to 8.3% after treatment. All insomnia remitters reported low cognitive arousal after treatment, whereas half of nonremitters continued reporting high cognitive arousal. Both nocturnal cognitive arousal and sleep effort were associated with same-week changes in insomnia throughout treatment, and sleep effort yielded a prospective effect on insomnia. Lower levels of nocturnal cognitive arousal and sleep effort prospectively predicted reductions in depression.

Conclusions

The present study offers preliminary evidence that reducing sleep effort and nocturnal cognitive arousal may serve as key mechanisms for alleviating insomnia and depression via mindfulness-based insomnia therapy. ClinicalTrials.gov ID: NCT04443959.

The Role of Dysfunctional Sleep Beliefs in Mediating the Outcomes of Web-Based Cognitive Behavioral Therapy for Insomnia in Community-Dwelling Older Adults: Protocol for a Single-Group, Nonrandomized Trial

BACKGROUND

Sleeping well is an essential part of good health. Older adult populations report a high rate of sleep problems, with recent studies suggesting that cognitive processes as well as behavioral and hyperarousal-related mechanisms could be important factors in the development and maintenance of insomnia. Individuals who have an asynchronous or uncoupled sleep pattern and sleep appraisal-those who complain about their sleep but do not have poor sleep quality, and vice versa-might show differences in subjective sleep and sleep perceptions and other characteristics that could impact their treatment outcomes following cognitive behavioral therapy for insomnia (CBT-I).

OBJECTIVE

The purpose of this protocol is to describe the rationale and methods for a nonrandomized, single-arm trial assessing objective and subjective sleep quality in community-dwelling older adults aged 60-80 years with synchronous sleep patterns and sleep appraisal compared to those in older adults with asynchronous sleep patterns and sleep appraisal. The trial will further examine the role of cognitive, behavioral, and hyperarousal processes in mediating the treatment outcomes of web-based CBT-I.

METHODS

This trial aims to recruit a sample of 60 participants, who will be assigned to 1 of 4 sleep groups based on their sleep pattern and sleep appraisal status: complaining good sleepers, complaining poor sleepers, noncomplaining good sleepers, and noncomplaining poor sleepers, respectively. The trial will be completed in 2 phases: phase 1 will assess objective sleep (measured via wrist actigraphy) and subjective (self-reported) sleep. Phase 2 will investigate the impact of a web-based CBT-I program on the sleep outcomes of individuals with uncoupled sleep compared to that of individuals without uncoupled sleep, as well as the mediators of CBT-I.

RESULTS

Recruitment began in March 2020, and the last participants were recruited by March 2021. A total of 65 participants completed phases 1 and 2. Data analysis for phase 1 was finished in December 2021, and data analysis for phase 2 was finalized in July 2022. The results for phase 1 were submitted for publication in March 2022, and those for phase 2 will be submitted by the end of December 2022.

CONCLUSIONS

This trial will provide guidance on factors that contribute to the variability of sleep in older adults and their sleep outcomes following CBT-I. The outcomes of this study could be valuable for future research attempting to tailor CBT-I to individual needs.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry ACTRN12619001509156; https://tinyurl.com/69hhdu2w.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/32705.

Stressor reflections, sleep, and psychological well-being: A pre-registered experimental test of self-distanced versus self-immersed reflections

Evidence supports the effectiveness of cuing people to analyse negative autobiographical experiences from self-distanced rather than self-immersed perspectives. However, the evidence on which this expectation resides is limited largely to static snapshots of mean levels of cognitive and emotional factors. Via a pre-registered, randomised controlled trial (N = 257), we examined the differential effectiveness of self-distanced relative to self-immersed reflections on mean levels and within-person variability of sleep duration and quality as well as psychological well-being over a 5-day working week. Except for sleep quality, we found that reflecting from a psychologically distanced perspective, overall, was no more effective for mean levels and within-person variability of sleep duration, well-being, and stress-related factors than when the current self is fully immersed in the experiential reality of the event. We consider several substantive and methodological considerations (e.g., dosage, salience of stressor event) that require interrogation in future research via experimental and longitudinal observational methods.

Examining whether Changes in Sleep Habits Predict Long-Term Sustainment of Treatment Gains in Individual Remitted from Insomnia after CBT-I

OBJECTIVES

Providers of Cognitive-Behavioral Therapy for Insomnia (CBT-I) are often asked whether the behavioral recommendations (e.g., stimulus control, sleep restriction) must be adhered to ad infinitum. We examined whether changes in sleep habits/behaviors are a life sentence, or whether patients who remit can relax their adherence while maintaining their treatment gains at 1-year follow-up (FU).

METHODS

Participants (N = 179) completed 2 weeks of sleep diaries and measures of insomnia severity and safety behaviors at baseline and following four sessions of CBT-I. Of the 137 patients that achieved remission, 77 completed these measures at 1-year FU.

RESULTS

Improvements in insomnia severity and total wake time (TWT) at post-treatment were maintained at FU (ps ≥ .52). Similarly, reductions in safety behaviors were maintained at FU (p - 1.00), whereas lingering in bed reduced during treatment (p < .001) but increased at FU (p < .001). Changes in sleep habits after treatment did not predict insomnia severity at FU. However, increases in time in bed positively predicted TWT at FU (p = .001).

CONCLUSIONS

Those who remit after CBT-I may generally relax their adherence to behavioral recommendations without significantly impacting their perceived insomnia symptoms 1 year after treatment despite some increases in TWT. Results increase our confidence in CBT-I as a brief and durable intervention.

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.

Using network intervention analysis to explore associations between participant expectations of and difficulties with cognitive behavioural therapy for insomnia and clinical outcome: A proof of principle study

BACKGROUND

Research about predictors of response to cognitive behaviour therapy for insomnia (CBT-I) is ongoing. We examined any whether pre-intervention expectations or post-intervention appraisals of difficulties in utilizing face to face (FtF) or digital (dCBT-I) versions of the therapy were associated with outcome.

METHODS

Self-rating data were extracted on 101 adult participants in a recent randomized controlled trial of FtF versus dCBT-I. Network intervention analyses were used to explore any associations between expectations of CBT-I at response at 9 weeks and between post-intervention ratings of difficulties, modality of therapy and response at 9-weeks and at 6-months.

RESULTS

Anticipated and actual difficulties in employing sleep restriction techniques predicted response in all network models. Modality of therapy played a more overt role in the 9-week outcome network, with FtF therapy more robustly associated with response. However, the direct association between FtF therapy and response was not found in the 6-month outcome network. Notable predictors of poor outcome at 9-weeks and 6-month follow-up were difficulties in accommodating CBT-I into work and daily routines and applying the rules of CBT-I.

CONCLUSIONS

This network intervention analysis highlights that self-confidence and ability in undertaking sleep restriction is a key active ingredient of CBT-I. Also, benefits and gains from access to the FtF version of this multi-component therapy were more apparent in the short than the longer term. However, it is important that findings from this proof of principle study are confirmed in further studies.

TIMELAPSE study-efficacy of low-dose amitriptyline versus cognitive behavioral therapy for chronic insomnia in patients with medical comorbidity: study protocol of a randomized controlled multicenter non-inferiority trial

Background

Insomnia is common in people with long-term medical conditions and is related to increased mortality and morbidity. Cognitive behavioral therapy for insomnia (CBT-I) is first choice treatment and effective for people with insomnia and comorbid long-term medical conditions. However, CBT-I has some limitations as it might not always be available or appeal to patients with medical conditions. Furthermore, a small proportion of patients do not respond to CBT-I. Preliminary evidence and clinical experience suggest that low-dose amitriptyline (AM) might be an effective alternative to treat insomnia in patients with medical comorbidity. In this randomized controlled trial, we will determine whether AM is non-inferior to the first choice treatment for insomnia, CBT-I.

Methods/design

This study will test if treatment with low-dose amitriptyline for insomnia in patients with medical comorbidity is non-inferior to CBT-I in a multicenter randomized controlled non-inferiority trial. Participants will be 190 adults with a long-term medical condition and insomnia. Participants will be randomly allocated to one of two intervention arms: 12 weeks AM (starting with 10 mg per day, and if ineffective at 3 weeks, doubling this dose) or 12 weeks of CBT-I consisting of 6 weekly sessions and a follow-up session 6 weeks later. The primary outcome is subjective insomnia severity, measured with the Insomnia Severity Index (ISI). The primary endpoint is at 12 weeks. Secondary outcomes include sleep quality (e.g., sleep efficiency), questionnaires on daytime functioning (physical functioning and impairment of functioning), and symptoms (e.g., fatigue, pain, anxiety) at 12 weeks and 12 months post treatment and relapse of insomnia until 12 months after treatment.

Discussion

Irrespective of the outcome, this study will be a much-needed contribution to evidence based clinical guidelines on the treatment of insomnia in patients with medical comorbidity.

Trial registration

Dutch Trial Register NTR NL7971. Registered on 18 August 2019

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-021-05868-4.

The Experiences and Determinants of Sleep Problems of Immigrant and Canadian-Born Older Adults-Analysis of Canadian Longitudinal Study on Aging Baseline Data

BACKGROUND

Although prevalent, limited knowledge is available on the experience of sleep problems (i.e., disturbance in sleep latency and in sleep maintenance) and their determinants in immigrant older adults.

PURPOSE

To compare immigrant and Canadian-born older adults' experiences of: 1) sleep problems, 2) determinants of sleep problems, categorized into precipitating and perpetuating factors, and 3) determinants most significantly contributing to each sleep problem.

METHODS

Baseline data obtained by the comprehensive cohort of the Canadian Longitudinal Study on Aging were analyzed. Participants 55+ years of age and with complete data on their country of birth comprised the sample, with 18,245 Canadian-born and 4,257 immigrant older adults. Single or multiple items were used to assess the precipitating (chronic condition, sleep disorders, pain, depressive symptoms, psychological distress, education, marital and socio-economic status) and perpetuating (smoking, alcohol consumption, physical activity) factors. Chi-square test and independent sample t-test were used in the comparison and multiple regression was applied to determine the most significant determinant of each sleep problem in each group of older adults.

RESULTS

Despite differences in a few determinants of sleep problems, the set of factors contributing to disturbance in sleep latency and maintenance was comparable for Canadian-born and immigrant older adults, and included: having a sleep disorder and high level of depressive symptoms and psychological distress.

CONCLUSION

The findings highlight the importance of public health campaigns to increase older adults' awareness of sleep problems, the factors that may contribute to disturbance in sleep, and strategies to prevent and/or manage sleep problems.

The effect of sleep restriction therapy for insomnia on sleep pressure and arousal: a randomised controlled mechanistic trial

STUDY OBJECTIVES

Sleep restriction therapy (SRT) effectively treats insomnia but mechanisms are poorly understood. Theoretical models suggest that potentiation of sleep pressure and reduction of arousal are key mechanisms of action. To our knowledge this has never been directly tested. We designed a randomised controlled trial with embedded mechanistic measurement to investigate if SRT causally modifies multidimensional assessments of sleep pressure and arousal.

METHODS

Participants aged 25-55 who met DSM-5 diagnostic criteria for insomnia disorder were randomised to four weeks of SRT or time in bed regularisation (TBR), a control intervention that involves prescription of a regular but not reduced time in bed. Sleep pressure was assessed through daily diary appraisal of morning and evening sleepiness, weekly Epworth sleepiness scale (ESS) scores, psychomotor vigilance, and NREM delta power (0.75-4.5Hz) from ambulatory polysomnographic recordings. Arousal was assessed through daily diary appraisal of cognitive arousal, the pre-sleep arousal scale (PSAS), and NREM beta power (15-32Hz). Outcomes were assessed at baseline (2-week period prior to randomisation), during the intervention phase (1-4 weeks post-randomisation), and at 12-week follow-up. We performed intention-to-treat analyses using linear mixed models. For continuous daily measures, the treatment period was split into early (weeks 1-2) and late (weeks 3-4) treatment.

RESULTS

Fifty-six participants (39 females, mean age=40.78±9.08) were assigned to SRT (n=27) or TBR (n=29). The SRT group showed enhanced sleep pressure relative to TBR, reflected in (1) enhanced sleepiness in the evening during early (d=1.17) and late treatment (d=0.92), and in the morning during early treatment (d=0.47); (2) higher daytime sleepiness on the ESS at weeks-1 and -2 (d=0.54, d=0.45); and (3) reduced psychomotor vigilance at week-1 (d=0.34). The SRT group also showed reduced arousal relative to TBR, reflected in lower levels of daily-monitored cognitive arousal during early treatment (d=0.53) and decreased PSAS total score at week-4 and week-12 (ds≥0.39). Power spectral analysis of all night NREM sleep revealed an increase in relative, but not absolute, EEG delta power at week-1 and week-4 (ds≥0.52) and a decrease of relative EEG beta power at week-4 (d=0.11).

CONCLUSION

For the first time we show that SRT increases sleep pressure and decreases arousal during acute implementation, providing support for mechanism-of-action.

Sleep-Related Cognitive Processes and the Incidence of Insomnia Over Time: Does Anxiety and Depression Impact the Relationship?

Aim: According to the Cognitive Model of Insomnia, engaging in sleep-related cognitive processes may lead to sleep problems over time. The aim was to examine associations between five sleep-related cognitive processes and the incidence of insomnia, and to investigate if baseline anxiety and depression influence the associations. Methods: Two thousand three hundred and thirty-three participants completed surveys on nighttime and daytime symptoms, depression, anxiety, and cognitive processes at baseline and 6 months after the first assessment. Only those without insomnia at baseline were studied. Participants were categorized as having or not having incident insomnia at the next time point. Baseline anxiety and depression were tested as moderators. Results: Three cognitive processes predicted incident insomnia later on. Specifically, more safety behaviors and somatic arousal at Time 1 increased the risk of developing insomnia. When investigating changes in the cognitive processes over time, reporting an increase of worry and safety behaviors also predicted incident insomnia. Depressive symptoms moderated the association between changes in worry and incident insomnia. Conclusion: These findings provide partial support for the hypothesis that cognitive processes are associated with incident insomnia. In particular, safety behaviors, somatic arousal, and worry increase the risk for incident insomnia. Preventative interventions and future research are discussed.

Disentangling the Relationship between Food Insecurity and Poor Sleep Health

The COVID-19 pandemic has created disruptions in global and national food supply chains. Along with an increase in the unemployment rate, this resulted in a rise in food insecurity at the community-level, threatening individual and family well-being. Food insecurity is associated with inadequate nutrient intakes, weight gain, and psychological distress, including anxiety and depressive symptoms, all of which are known to affect sleep. Yet, little is known about whether and how food insecurity is associated with sleep health, a critical but underrecognized health outcome. This paper reviews literature describing associations between food insecurity and sleep, summarizes key findings based on proposed mechanisms, and discusses directions for future research.

The effect of sleep-wake intraindividial variability in digital cognitive behaviour therapy for insomnia: A mediation analysis of a large-scale RCT

Study Objectives

Digital cognitive behavioral therapy for insomnia (dCBT-I) is an effective treatment for insomnia. However, less is known about mediators of its benefits. The aim of the present study was to test if intraindividual variability in sleep (IIV) was reduced with dCBT-I, and whether any identified reduction was a mediator of dCBT-I on insomnia severity and psychological distress.

Methods

In a two-arm randomized controlled trial (RCT), 1720 adults with insomnia (dCBT-I = 867; patient education about sleep = 853) completed the Insomnia Severity Index (ISI), the Hospital Anxiety and Depression Scale (HADS) and sleep diaries, at baseline and 9-week follow-up. Changes in IIV were analyzed using linear mixed modeling followed by mediation analyses of ISI, HADS, and IIV in singular sleep metrics and composite measures (behavioral indices (BI-Z) and sleep disturbance indices (SI-Z)).

Results

dCBT-I was associated with reduced IIV across all singular sleep metrics, with the largest between-group effect sizes observed for sleep onset latency (SOL). Reduced IIV for SOL and wake after sleep onset had the overall greatest singular mediating effect. For composite measures, SI-Z mediated change in ISI (b = −0.74; 95% confidence interval (CI) −1.04 to −0.52; 13.3%) and HADS (b = −0.40; 95% CI −0.73 to −0.18; 29.2%), while BI-Z mediated minor changes.

Conclusion

Reductions in IIV in key sleep metrics mediate significant changes in insomnia severity and especially psychological distress when using dCBT-I. These findings offer important evidence regarding the therapeutic action of dCBT-I and may guide the future development of this intervention.

Clinical trials

Name: Overcoming Insomnia: Impact on Sleep, Health and Work of Online CBT-I

Registration number: NCT02558647

URL: https://clinicaltrials.gov/ct2/show/NCT02558647?cond=NCT02558647&draw=2&rank=1

Change in Dysfunctional Sleep-Related Beliefs is Associated with Changes in Sleep and Other Health Outcomes Among Older Veterans With Insomnia: Findings From a Randomized Controlled Trial

BACKGROUND

Cognitive behavioral therapy for insomnia (CBTI) targets changing dysfunctional sleep-related beliefs. The impact of these changes on daytime functioning in older adults is unknown.

PURPOSE

We examined whether changes in sleep-related beliefs from pre- to post-CBTI predicted changes in sleep and other outcomes in older adults.

METHOD

Data included 144 older veterans with insomnia from a randomized controlled trial testing CBTI. Sleep-related beliefs were assessed with the Dysfunctional Beliefs and Attitudes about Sleep-16 (DBAS-16, subscales: Consequences, Worry/Helplessness, Sleep Expectations, Medication). Outcomes included sleep diary variables, actigraphy-measured sleep efficiency, Pittsburgh Sleep Quality Index (PSQI), Insomnia Severity Index (ISI), Epworth Sleepiness Scale (ESS), Flinders Fatigue Scale (FFS), Patient Health Questionnaire-9, and health-related quality of life. Analyses compared slope of change in DBAS subscales from baseline to posttreatment between CBTI and control, and assessed the relationship between DBAS change and the slope of change in outcomes from baseline to 6 months.

RESULTS

Compared to controls, the CBTI group demonstrated stronger associations between improvement in DBAS-Consequences and subsequent improvement in PSQI, ISI, ESS, and FFS. The CBTI group also demonstrated stronger associations between improvement in DBAS-Worry/Helplessness and subsequent improvements in PSQI, ISI, and FFS; improvements in DBAS-Medication and PSQI; and improvements in DBAS-Sleep Expectations and wake after sleep onset (sleep diary) and FFS (all p < .05).

CONCLUSIONS

Significant reduction in dysfunctional sleep-related beliefs following CBTI in older adults predicted improvement in several outcomes of sleep and daytime functioning. This suggests the importance of addressing sleep-related beliefs for sustained improvement with CBTI in older veterans.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT00781963.

Yoga nidra practice shows improvement in sleep in patients with chronic insomnia: A randomized controlled trial

Background Yoga nidra is practised by sages for sleep. The practice is simple to use and has been clearly laid out, but its role in the treatment of chronic insomnia has not been well studied. Methods In this randomized parallel-design study conducted during 2012-16, we enrolled 41 patients with chronic insomnia to receive conventional intervention of cognitive behavioural therapy for insomnia (n=20) or yoga nidra (n=21). Outcome measures were both subjective using a sleep diary and objective using polysomnography (PSG). Salivary cortisol levels were also measured. PSG was done before the intervention in all patients and repeated only in those who volunteered for the same. Results Both interventions showed an improvement in subjective total sleep time (TST), sleep efficiency, wake after sleep onset, reduction in total wake duration and enhancement in subjective sleep quality. Objectively, both the interventions improved TST and total wake duration and increased N1% of TST. Yoga nidra showed marked improvement in N2% and N3% in TST. Salivary cortisol reduced statistically significantly after yoga nidra (p=0.041). Conclusion Improvement of N3 sleep, total wake duration and subjective sleep quality occurred following yoga nidra practice. Yoga nidra practice can be used for treatment of chronic insomnia after supervised practice sessions.

Does the guided online cognitive behavioral therapy for insomnia "i-Sleep youth" improve sleep of adolescents and young adults with insomnia after childhood cancer? (MICADO-study): study protocol of a randomized controlled trial

BACKGROUND

Adolescents and young adults who had childhood cancer are at increased risk for insomnia, due to being critically ill during an important phase of their life for the development of good sleep habits. Insomnia is disabling and prevalent after childhood cancer (26-29%) and negatively impacts quality of life, fatigue, pain, and general functioning and is often associated with other (mental) health problems. Insomnia and a history of childhood cancer both increase the risk of adverse health outcomes, posing a double burden for adolescents who had childhood cancer. The first-line treatment for insomnia is cognitive behavioral therapy for insomnia (CBT-I). However, access to this type of care is often limited. The guided online CBT-I treatment "i-Sleep" has been developed to facilitate access via online care. i-Sleep is shown effective in adult (breast cancer) patients, but it is unknown if iCBT-I is effective in pediatric oncology.

METHODS/DESIGN

We developed a youth version of i-Sleep. Our aim is to evaluate its effectiveness in a national randomized-controlled clinical trial comparing iCBT-I to a waiting-list control condition at 3 and 6 months (n = 70). The intervention group will be also assessed at 12 months to see whether the post-test effects are maintained. Adolescents and young adults aged 12-30 years with insomnia, diagnosed with (childhood) cancer, currently at least 6 months since their last cancer treatment will be eligible. Outcomes include sleep efficiency (actigraphic), insomnia severity (self-report), sleep and circadian activity rhythm parameters, fatigue, health-related quality of life, perceived cognitive functioning, chronic distress, depressive and anxiety symptoms, and intervention acceptability.

DISCUSSION

Insomnia is prevalent in the pediatric oncology population posing a double health burden for adolescents and young adults who had childhood cancer. If guided iCBT-I is effective, guidelines for insomnia can be installed to treat insomnia and potentially improve quality of life and the health of adolescents and young adults who had childhood cancer.

TRIAL REGISTRATION

NL7220 (NTR7419; Netherlands Trial register). Registered on 2 August 2018.

How does cognitive behavioural therapy for insomnia work? A systematic review and meta-analysis of mediators of change

Insomnia is prevalent and debilitating, comprising sustained difficulties initiating or maintaining sleep. Cognitive-behavioural therapy for insomnia (CBT-I) is a multicomponent intervention recommended as the first-line treatment, but the mediators of change remain unclear. This systematic review and meta-analysis aimed to synthesise and evaluate the evidence for potential mediators of CBT-I. Searches were performed for studies published until February 2021, reporting on mediation analyses with CBT-I. Seventeen unique samples of adults with insomnia (20 studies, N = 3125) were included. Two-stage structural equation modelling was applied to the available data, where 7 studies examined the cognitive mediator, 'dysfunctional beliefs about sleep', 5 studies examined a hyperarousal mediator, and 3 studies examined the behavioural mediator, 'time in bed'. There was evidence in support of changes in dysfunctional beliefs as a cognitive mediator of insomnia symptom improvement following CBT-I. There was more limited evidence in support of changes in hyperarousal-related mediators, and no significant effect of time in bed as a mediator. Numerous studies recorded diary-based measures of potential behavioural mediators, but analyses of these variables were not typically conducted. The most serious limitation of the evidence base is that the temporal precedence of mediator changes cannot be established. Future studies should consider: i) using mid-treatment measurements of mediator changes; ii) reporting on mediator psychometric properties; and iii) explicitly stating analyses as pre-specified or exploratory.

Sleep Disorders in Stroke: An Update on Management

Stroke is a leading cause of disability and mortality all over the world. Due to an aging population, the incidence of stroke is rising significantly, which has led to devastating consequences for patients. In addition to traditional risk factors such as age, hypertension, hyperlipidemia, diabetes and atrial fibrillation, sleep disorders, as independent modifiable risk factors for stroke, have been highlighted increasingly. In this review, we provide an overview of common types of current sleep disturbances in cerebrovascular diseases, including insomnia, hypersomnia, breathing-related sleep disorders, and parasomnias. Moreover, evidence-based clinical therapeutic strategies and pitfalls of specific sleep disorders after stroke are discussed. We also review the neurobiological mechanisms of these treatments as well as their effects on stroke. Since depression after stroke is so prevalent and closely related to sleep disorders, treatments of post-stroke depression are also briefly mentioned in this review article.

A Cognitive Behavioral Model Proposing That Clinical Burnout May Maintain Itself

Burnout is common in many countries and is associated with several other problems such as depression, anxiety, insomnia, and memory deficits, and prospectively it predicts long-term sick-leave, cardiovascular disease, and death. Clinical burnout or its residual symptoms often last several years and a common assumption is that recovery takes a long time by nature, despite full time sick-leave and the absence of work stress. The literature suggests models that hypothetically explain the development, but not maintenance, of the syndrome. Based on cognitive and behavioral principles, stress research, and stress theories, this paper describes a theoretical model explaining how clinical burnout can develop and be maintained. While the development of clinical burnout is mainly explained by prolonged stress reactions and disturbed recovery processes due to work related stressors, maintenance of the syndrome is particularly explained by prolonged stress reactions and disturbed recovery processes due to the new context of experiencing burnout and being on sick-leave. Worry about acquired memory deficits, passivity and excessive sleep, shame, fear of stress reactions, and the perception of not being safe are examples of responses that can contribute to the maintenance. The model has important implications for research and how to intervene in clinical burnout. For example, it can offer support to professional care providers and patients in terms of focusing on, identifying, and changing current contextual factors and behaviors that maintain the individual’s clinical burnout symptoms and by that facilitate burnout recovery. Regarding research, the model provides a highly important reason for researchers to study contextual factors and behaviors that contribute to the maintenance of clinical burnout, which has been neglected in research.

Cognitive behavioural therapy for insomnia for patients with co-morbid generalized anxiety disorder: an open trial on clinical outcomes and putative mechanisms

BACKGROUND

Very little is known concerning the efficacy of psychosocial treatments for patients with insomnia disorder co-morbid with generalized anxiety disorder (GAD).

AIM

The aim was to examine the efficacy of cognitive behavioral therapy for insomnia (CBT-I) for patients with insomnia disorder co-morbid with GAD.

METHOD

Given the limited, previous research on therapies for patients with insomnia disorder co-morbid with GAD, an open trial design was used. Twenty-four patients with insomnia disorder and GAD were administered CBT-I across 10 weeks. Across the study period to 6 months follow-up, the participants completed measures indexing insomnia, anxiety, worry, depression, functional impairment, quality of life, treatment perception (credibility, expectancy and satisfaction), adverse events and putative mechanisms.

RESULTS

Moderate to large effect sizes for CBT-I were observed for insomnia symptoms. In terms of insomnia severity, approximately 61% of the patients responded to CBT-I and 26-48% remitted. Moderate to large effect sizes were also demonstrated for GAD symptoms, depression, functional impairment and quality of life. Roughly one-third of the participants reported an adverse event during CBT-I. Five of the seven putative mechanisms were significantly reversed in the expected direction, i.e. all four cognitive process measures and time in bed.

CONCLUSIONS

This open trial indicates that CBT-I is an efficacious intervention for patients with insomnia disorder co-morbid with GAD. The results highlight the need for further research using a randomized controlled trial design with analyses of mechanisms of change.

The acute effects of sleep restriction therapy for insomnia on circadian timing and vigilance

Sleep-restriction therapy (SRT) has been shown to improve insomnia symptoms by restricting sleep opportunity. Curtailment of time in bed affects the duration and consolidation of sleep, but also its timing. While recent work suggests that people with insomnia are characterised by misalignment between circadian and behavioural timing of sleep, no study has investigated if SRT modifies this relationship. The primary aim of the present study was to examine change in phase angle after 2 weeks of SRT. As a secondary aim, we also sought to assess the effect of SRT on psychomotor vigilance. Following a 1-week baseline phase, participants implemented SRT for 2 consecutive weeks. Phase angle was derived from the difference between the decimal clock time of dim light melatonin onset (DLMO) and attempted sleep time. Secondary outcomes included vigilance (assessed via hourly measurement during the DLMO laboratory protocol), sleep continuity (assessed via sleep diary and actigraphy), and insomnia severity. Eighteen participants meeting insomnia criteria (mean [SD] age 37.06 [8.99] years) took part in the study. Consistent with previous research, participants showed robust improvements in subjective and objective sleep continuity, as well as reductions in insomnia severity. The primary outcome (phase angle) was measurable in 15 participants and revealed an increase of 34.8 min (~0.58 hr; 95% confidence interval [CI] 0.01-1.15) from baseline to post-treatment (mean [SD] 2.27 [0.94] versus 2.85 [1.25] hr). DLMO remained relatively stable (20:49 versus 21:01 hours), while attempted sleep was 46.8 min later (~0.78 hr; 95%CI 0.41-1.15; 23:05 versus 23:52 hours). For psychomotor vigilance, reaction time was delayed (by 52.71 ms, 95% CI 34.44-70.97) and number of lapses increased (by 5.84, 95% CI 3.93-7.75) after SRT. We show that SRT increases phase angle during treatment, principally by delaying the timing of sleep attempt. Future studies are needed to test if an increase in phase angle is linked to clinical improvement. Finally, reduction in vigilance after SRT appears to be of similar magnitude to normal sleepers undergoing experimental sleep restriction, reinforcing the importance of appropriate safety advice during implementation.

Isolating the role of time in bed restriction in the treatment of insomnia: a randomized, controlled, dismantling trial comparing sleep restriction therapy with time in bed regularization

Study Objectives

Sleep restriction therapy (SRT) is one of the most effective treatments for insomnia. Restriction of time in bed (TIB) is assumed to be the central mechanism through which SRT improves sleep consolidation and reduces insomnia symptoms. This hypothesis has never been directly tested. We designed a randomized, controlled, dismantling trial in order to isolate the role of TIB restriction in driving both clinical and polysomnographic sleep outcomes.

Methods

Participants aged 25–55 who met diagnostic criteria for insomnia disorder were block-randomized (1:1) to 4 weeks of SRT or time in bed regularization (TBR), a treatment that involves the prescription of a regular but not reduced TIB. The primary outcome was assessed with the insomnia severity index (ISI) at baseline, 4-, and 12-weeks post-randomization. Secondary outcomes included sleep continuity (assessed via polysomnography, actigraphy, and diary) and quality of life. We performed intention-to-treat analyses using linear mixed models.

Results

Fifty-six participants (39 females, mean age = 40.78 ± 9.08) were assigned to SRT (n = 27) or TBR (n = 29). Daily monitoring of sleep via diaries and actigraphy confirmed large group differences in TIB (d range = 1.63–1.98). At 4-weeks post-randomization, the adjusted mean difference for the ISI was −4.49 (d = −1.40) and −4.35 at 12 weeks (d = −1.36), indicating that the SRT group reported reduced insomnia severity relative to TBR. Robust treatment effects in favor of SRT were also found for objective and self-reported sleep continuity variables (d range = 0.40–0.92) and sleep-related quality of life (d = 1.29).

Conclusions

For the first time, we demonstrate that TIB restriction is superior to the regularization of TIB on its own. Our results underscore the centrality of the restriction component in reducing insomnia symptoms and consolidating sleep.

Light-enhanced cognitive behavioural therapy for sleep and fatigue: study protocol for a randomised controlled trial during chemotherapy for breast cancer

BACKGROUND

Women with breast cancer experience a significantly higher prevalence of sleep disturbance and insomnia than the general population. The experience of persistent sleep disturbance places these women at a higher risk of psychological and physical morbidity and a reduced quality of life. Treatment for sleep in this population is not part of routine care and is often managed inadequately. This randomised controlled trial will examine the combined effects of cognitive behavioural therapy (CBT) and bright light therapy (BLT) on the symptoms of insomnia, fatigue and mental health.

METHOD/DESIGN

Women diagnosed with breast cancer who receive intravenous chemotherapy treatment at a quaternary referral metropolitan cancer centre in Melbourne, Australia, will be recruited. Recruitment will occur after diagnosis and prior to completion of chemotherapy. Eligible women will be randomised to the combined CBT and BLT intervention (CBT+) or relaxation audio-enhanced treatment as usual (TAU+). The CBT+ group will receive one face-to-face session on sleep strategies, one subsequent telephone call, and seven email packages containing CBT-based information and strategies. CBT+ participants will also wear Luminette® light glasses for 20 min each morning for the 6-week duration of the intervention. Women in TAU+ will receive two relaxation audio tracks via email. Outcomes will be measured at multiple points throughout the 6 weeks. Primary outcomes will be symptoms of insomnia and sleep efficiency, measured using the Insomnia Severity Index and a self-reported sleep diary. Secondary outcomes include objective measures of sleep assessed using the ActiGraph wGT3X-BT, and sleep-related complaints, fatigue and mental health, all assessed using the Patient-Reported Outcomes Measurement Information System (PROMIS). Data will also be collected on potential treatment moderators and mechanisms and adherence to treatment. There will be 3-month follow-up measurements of insomnia symptoms, fatigue, sleep-related impairment, sleep disturbance, depression and anxiety.

DISCUSSION

This is the first randomised controlled trial to combine CBT and BLT for the treatment of sleep disturbance in women with breast cancer. This novel design addresses the multiple causal factors for sleep complaints in this population. Results from this trial will advance knowledge in this field and may have important clinical implications for how best to treat sleep disturbance and insomnia in this population. If effective, the largely email-based format of the intervention would allow for relatively easy translation.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry (ANZCTR), ACTRN12618001255279. Retrospectively registered on 25 July 2018.

Changes in dysfunctional beliefs about sleep after cognitive behavioral therapy for insomnia: A systematic literature review and meta-analysis

Cognitive behavioral therapy for insomnia (CBT-I) is the preferred treatment for chronic insomnia and sleep-related cognitions are one target of treatment. There has been little systematic investigation of how sleep-related cognitions are being assessed in CBT-I trials and no meta-analysis of the impact of CBT-I on dysfunctional beliefs about sleep, a core cognitive component of treatment. Academic Search Complete, Medline, CINAHL and PsychInfo from 1990 to 2018 were searched to identify randomized controlled trials of CBT-I in adults (≥18 years) reporting some measure of sleep-related cognitions. Sixteen randomized controlled trials were identified comparing 1134 CBT-I and 830 control subjects. The Dysfunctional Beliefs and Attitudes about Sleep Scale was utilized almost exclusively to assess sleep-related cognitions in these trials. Hedge's g at 95% confidence interval (CI) was calculated to assess CBT-I effect size at post-treatment compared to controls. CBT-I significantly reduced dysfunctional beliefs about sleep (g = -0.90, 95% CI -1.19, -0.62) at post-treatment. Three trials contributed data to estimate effect size for long-term effects (g = -1.04, 95% CI -2.07, -0.02) with follow up time ranging from 3 to 18 mo. We concluded that cognitive behavioral therapy for insomnia has moderate to large effects on dysfunctional beliefs about sleep.

Efficacy of a Self-Help Web-Based Recovery Training in Improving Sleep in Workers: Randomized Controlled Trial in the General Working Population

BACKGROUND

Sleep complaints are among the most prevalent health concerns, especially among workers, which may lead to adverse effects on health and work. Internet-delivered cognitive behavioral therapy for insomnia (iCBT-I) offers the opportunity to deliver effective solutions on a large scale. The efficacy of iCBT-I for clinical samples has been demonstrated in recent meta-analyses, and there is evidence that iCBT-I is effective in the working population with severe sleep complaints. However, to date, there is limited evidence from randomized controlled trials that iCBT-I could also be an effective tool for universal prevention among the general working population regardless of symptom severity. Although increasing evidence suggests that negatively toned cognitive activity may be a key factor for the development and maintenance of insomnia, little is known about how iCBT-I improves sleep by reducing presleep cognitive activity.

OBJECTIVE

This study aimed to examine the efficacy of a self-help internet-delivered recovery training, based on principles of iCBT-I tailored to the work-life domain, among the general working population. General and work-related cognitive activities were investigated as potential mediators of the intervention's effect.

METHODS

A sample of 177 workers were randomized to receive either the iCBT-I (n=88) or controls (n=89). The intervention is a Web-based training consisting of six 1-week modules. As the training was self-help, participants received nothing but technical support via email. Web-based self-report assessments were scheduled at baseline, at 8 weeks, and at 6 months following randomization. The primary outcome was insomnia severity. Secondary outcomes included measures of mental health and work-related health and cognitive activity. In an exploratory analysis, general and work-related cognitive activities, measured as worry and work-related rumination, were investigated as mediators.

RESULTS

Analysis of the linear mixed effects model showed that, relative to controls, participants who received iCBT-I reported significantly lower insomnia severity scores at postintervention (between-group mean difference -4.36; 95% CI -5.59 to - 3.03; Cohen d=0.97) and at 6-month follow-up (between-group difference: -3.64; 95% CI -4.89 to -2.39; Cohen d=0.86). The overall test of group-by-time interaction was significant (P<.001). Significant differences, with small-to-large effect sizes, were also detected for cognitive activity and for mental and work-related health, but not for absenteeism. Mediation analysis demonstrated that work-related rumination (indirect effect: a₁b₁=-0.80; SE=0.34; 95% boot CI -1.59 to -0.25) and worry (indirect effect: a₂b₂=-0.37; SE=0.19; 95% boot CI -0.85 to -0.09) mediate the intervention's effect on sleep.

CONCLUSIONS

A self-help Web-based recovery training, grounded in the principles of iCBT-I, can be effective in the general working population, both short and long term. Work-related rumination may be a particularly crucial mediator of the intervention's effect, suggesting that tailoring interventions to the workplace, including components to reduce the work-related cognitive activity, might be important when designing recovery interventions for workers.

TRIAL REGISTRATION

German Clinical Trials Register DRKS00007142; https://www.drks.de/DRKS00007142.

Cognitive behavioral therapy for insomnia: A meta-analysis of long-term effects in controlled studies

Cognitive behavioral therapy for insomnia (CBT-I) is a treatment with moderate to large effects. These effects are believed to be sustained long-term, but no systematic meta-analyses of recent evidence exist. In this present meta-analysis, we investigate long-term effects in 30 randomized controlled trials (RCTs) comparing CBT-I to non-active control groups. The primary analyses (n = 29 after excluding one study which was an outlier) showed that CBT-I is effective at 3-, 6- and 12-mo compared to non-active controls: Hedges g for Insomnia severity index: 0.64 (3 m), 0.40 (6 m) and 0.25 (12 m); sleep onset latency: 0.38 (3 m), 0.29 (6 m) and 0.40 (12 m); sleep efficiency: 0.51 (3 m), 0.32 (6 m) and 0.35 (12 m). We demonstrate that although effects decline over time, CBT-I produces clinically significant effects that last up to a year after therapy.

Internet-Delivered Cognitive Behavioral Therapy for Insomnia: Tailoring Cognitive Behavioral Therapy for Insomnia for Patients with Chronic Insomnia

Chronic insomnia is preferably treated with cognitive behavioral therapy for insomnia (CBTI), but many insomnia sufferers receive medication instead, likely because of high costs, lack of knowledge about optimal insomnia treatment among physicians, and lack of CBTI-trained professionals in mental health care. A possible solution is to offer CBTI through the Internet: I-CBTI. I-CBTI is generally acceptable to patients and greatly improves insomnia symptoms. We review the state of knowledge around I-CBTI and its effects. CBTI's effectiveness is influenced by treatment characteristics and patient-specific factors. We review potential factors that help identify which patients may benefit from I-CBTI.

Gender Differences in Perpetuating Factors, Experience and Management of Chronic Insomnia

The higher prevalence of insomnia in women has been attributed to biological factors, which are less likely than cognitive and behavioral factors to play a role in perpetuating insomnia. Gender differences in perpetuating factors have not been extensively examined. This study compared men's and women's self-reports of factors that perpetuate insomnia; experience of symptoms, perceived severity and impact on daytime functioning; and use of strategies to manage insomnia. Data were collected at baseline, using reliable and valid measures, in a project that evaluated behavioral therapies for insomnia. The sample (N = 739) consisted of women (62.4%) and men (37.6%). Gender differences were found in: 1) perpetuating factors: men took more naps and held more unhelpful beliefs about insomnia, whereas women experienced higher pre-sleep arousal; 2) perception of insomnia severity: higher among women; 3) perceived impact of insomnia: higher fatigue among women; and 4) use of strategies (higher in women) to manage insomnia. Gender differences were of a small size but could be associated with women's stress, expression of somatic symptoms, and interest in maintaining their own health to meet multiple role demands.

Comparing the Experience of and Factors Perpetuating Chronic Insomnia Severity Among Young, Middle-Aged, and Older Adults

The prevalence of chronic insomnia is on the rise among young, middle-aged, and older adults. This secondary data analysis examined age-group differences in the experience of and factors perpetuating insomnia severity. Pretest data, obtained from a trial of behavioral interventions, were collected from 742 participants, using psychometrically sound measures of perpetuating factors (sleep habits, unhelpful beliefs, presleep arousal), insomnia experience (symptoms, perceived severity), and consequences or impact on daytime functioning. The age groups reported different insomnia symptoms (difficulty maintaining sleep in older adults) and impact on daytime functioning (poorer in older adults), but the same level of perceived insomnia severity. Unhelpful beliefs about sleep predicted insomnia severity in all age groups, and presleep arousal contributed to insomnia in young adults. The results highlight the importance of adequately managing chronic insomnia to minimize its impact on daytime functioning in all age groups, and of tailoring therapy to their experiences.

Who benefits from adolescent sleep interventions? Moderators of treatment efficacy in a randomized controlled trial of a cognitive-behavioral and mindfulness-based group sleep intervention for at-risk adolescents

BACKGROUND

The aim of this study was to test moderators of therapeutic improvement in an adolescent cognitive-behavioral and mindfulness-based group sleep intervention. Specifically, we examined whether the effects of the program on postintervention sleep outcomes were dependent on participant gender and/or measures of sleep duration, anxiety, depression, and self-efficacy prior to the interventions.

METHOD

Secondary analysis of a randomized controlled trial conducted with 123 adolescent participants (female = 59.34%; mean age = 14.48 years, range 12.04-16.31 years) who had elevated levels of sleep problems and anxiety symptoms. Participants were randomized into either a group sleep improvement intervention (n = 63) or group active control 'study skills' intervention (n = 60). The sleep intervention ('Sleep SENSE') was cognitive behavioral in approach, incorporating sleep education, sleep hygiene, stimulus control, and cognitive restructuring, but also had added anxiety-reducing, mindfulness, and motivational interviewing elements. Components of the active control intervention ('Study SENSE') included personal organization, persuasive writing, critical reading, referencing, memorization, and note taking. Participants completed the Pittsburgh Sleep Quality Index (PSQI), Spence Children's Anxiety Scale (SCAS), Center for Epidemiologic Studies Depression Scale (CES-D), and General Self-Efficacy Scale (GSE) and wore an actigraph and completed a sleep diary for five school nights prior to the interventions. Sleep assessments were repeated at postintervention. The trial is registered with the Australian New Zealand Clinical Trials Registry (ACTRN12612001177842; http://www.anzctr.org.au/TrialSearch.aspx?searchTxt=ACTRN12612001177842&isBasic=True).

RESULTS

The results showed that compared with the active control intervention, the effect of the sleep intervention on self-reported sleep quality (PSQI global score) at postintervention was statistically significant among adolescents with relatively moderate to high SCAS, CES-D, and GSE prior to the intervention, but not among adolescents with relatively low SCAS, CES-D, and GSE prior to the intervention. The results were consistent across genders. However, the effects of the sleep intervention on actigraphy-measured sleep onset latency and sleep diary-measured sleep efficiency at postintervention were not dependent on actigraphy-measured total sleep time, SCAS, CES-D, or GSE prior to the intervention.

CONCLUSIONS

This study provides evidence that some sleep benefits of adolescent cognitive-behavioral sleep interventions are greatest among those with higher levels of anxiety and depressive symptoms, suggesting that this may be an especially propitious group to whom intervention efforts could be targeted. Furthermore, adolescents with lower levels of self-efficacy may need further targeted support (e.g. additional motivational interviewing) to help them reach treatment goals.

Mechanisms underlying the association between insomnia, anxiety, and depression in adolescence: Implications for behavioral sleep interventions

There is robust evidence of an association between insomnia, anxiety, and depression in adolescence. The aim of this review is to describe and synthesize potential mechanisms underlying this association and explore implications for the design of adolescent behavioral sleep interventions. Specifically, we examine whether insomnia symptoms are a mechanism for the development of internalizing symptoms in adolescence and whether sleep interventions are an effective treatment for both insomnia and internalizing symptoms in adolescence because they target the shared mechanisms underlying these disorders. Research using different methodologies points to the role of sequential, parallel, and interacting mechanisms. In this paper, we review a wide range of relevant biological (i.e., polymorphisms and dysregulation in serotonin, dopamine, and circadian clock genes; alterations in corticolimbic and mesolimbic brain circuits; cortisol reactivity to stress; inflammatory cytokine dysregulation; biased memory consolidation; changes in sleep architecture), psychological (i.e., cognitive inflexibility, interpretational biases, judgment biases, negative attribution styles, worry, rumination, biased attention to threat, dysfunctional beliefs and attitudes about sleep, misperception of sleep deficit), and social mechanisms (i.e., reduced and impaired social interactions, unhelpful parenting behaviors, family stress) and propose an integrative multilevel model of how these phenomena may interact to increase vulnerability to both insomnia and internalizing disorders. Several 'biopsychosocial' mechanisms hold promise as viable treatment targets for adolescent behavioral sleep interventions, which may reduce both insomnia and internalizing symptoms.

CBT-I and HT-I group therapy for adults with insomnia in comparison to those with insomnia and comorbid depression - a pilot study

PURPOSE

The aim of this study was to examine the effectiveness of a combined cognitive-behavioral therapy for insomnia (CBT-I) and hypnotherapy for insomnia (HT-I) program for insomnia patients with or without additional depression regarding depressive symptoms and various sleep parameters.

PATIENTS AND METHODS

A sample of 63 patients suffering from insomnia received a six-session sleep intervention, which combined cognitive-behavioral and hypnotherapeutical elements. Due to violating exclusion criteria, data of 37 patients were analyzed. Ten patients had insomnia comorbid with depression, whereas 27 patients had insomnia only. Sleep diaries were implemented to measure various sleep parameters, whereas depressive symptomatology was assessed with the anxiety and depression scale and Symptom-Checklist-90-R at baseline, before and after the intervention, as well as at 3-months follow-up.

RESULTS

Depressive symptoms decreased from pre to post measurement and follow-up for patients with insomnia comorbid with depression, whereas scores of patients with only insomnia remained relatively on a low level. Both groups showed a significant increase of sleep efficiency and a significant decrease of the duration of wake after sleep onset. However, only patients with insomnia and depression revealed a significant reduction of sleep-onset latency and a higher level of regeneration. Nondepressive insomniacs, on the other hand, showed a significant increase of performance from post measurement to follow-up. For both groups, no change over time was found for number of wake after sleep onset, total sleep time, mood in the morning and evening.

CONCLUSION

Combining CBT-I and HT-I is effective in reducing depressive symptoms and improving sleep. Therefore, nonresponders to other forms of therapy, eg, pharmacological, interpersonal, or cognitive-behavioral therapy, might benefit from the combined CBT-I/HT-I intervention.