Objective sleep disturbance is associated with poor response to cognitive and behavioral treatments for insomnia in postmenopausal women

Insomnia nosology: a systematic review and critical appraisal of historical diagnostic categories and current phenotypes

Insomnia nosology has significantly evolved since the Diagnostic and Statistical Manual (DSM)-III-R first distinguished between 'primary' and 'secondary' insomnia. Prior International Classification of Sleep Disorders (ICSD) nosology 'split' diagnostic phenotypes to address insomnia's heterogeneity and the DSM nosology 'lumped' them into primary insomnia, while both systems assumed causality for insomnia secondary to health conditions. In this systematic review, we discuss the historical phenotypes in prior insomnia nosology, present findings for currently proposed insomnia phenotypes based on more robust approaches, and critically appraise the most relevant ones. Electronic databases PsychINFO, PubMED, Web of Science, and references of eligible articles, were accessed to find diagnostic manuals, literature on insomnia phenotypes, including systematic reviews or meta-analysis, and assessments of the reliability or validity of insomnia diagnoses, identifying 184 articles. The data show that previous insomnia diagnoses lacked reliability and validity, leading current DSM-5-TR and ICSD-3 nosology to 'lump' phenotypes into a single diagnosis comorbid with health conditions. However, at least two new, robust insomnia phenotyping approaches were identified. One approach is multidimensional-multimethod and provides evidence for self-reported insomnia with objective short versus normal sleep duration linked to clinically relevant outcomes, while the other is multidimensional and provides evidence for two to five clusters (phenotypes) based on self-reported trait, state, and/or life-history data. Some approaches still need replication to better support whether their findings identify true phenotypes or simply different patterns of symptomatology. Regardless, these phenotyping efforts aim at improving insomnia nosology both as a classification system and as a mechanism to guide treatment.

Objective sleep duration and response to combined pharmacotherapy and cognitive behavioral insomnia therapy among patients with comorbid depression and insomnia: a report from the TRIAD study

STUDY OBJECTIVES

Several studies have shown that patients with short sleep duration show a poor response to cognitive behavioral therapy for insomnia (CBT-I), but such studies have not included patients with comorbid conditions. The current study was conducted to determine whether pretreatment sleep duration moderates the response of patients with major depression and insomnia disorders to a combined CBT-I and antidepressant medication treatment.

METHODS

This study comprised a secondary analysis of a larger randomized trial that tested combined CBT-I/antidepressant medication treatment of patients with major depression and insomnia. Participants (n = 99; 70 women; Mage = 47.712.4 years) completed pretreatment polysomnography and then were randomly assigned to a 12-week treatment with antidepressant medication combined with CBT-I or a sham therapy. Short and longer sleepers were defined using total sleep time cutoffs of < 5, < 6, and < 7 hours for short sleep. Insomnia and depression remission ascertained respectively from the Insomnia Severity Index and Hamilton Rating Scale for Depression were used to compare treatment responses of short and longer sleepers defined by the cutoffs mentioned.

RESULTS

Logistic regression analyses showed that statistically significant results were obtained only when the cutoff of < 5 hours of sleep was used to define "short sleep." Both the CBT-I recipients with < 5 hours of sleep (odds ratio = 0.053; 95% confidence interval = 0.006-0.499) and the sham-therapy group with ≥ 5 hours of sleep (odds ratio = 0.149; 95% confidence interval = 0.045-0.493) were significantly less likely to achieve insomnia remission than were CBT-I recipients with ≥ 5 hours of sleep. The shorter sleeping CBT-I group (odds ratio = 0.118; 95% confidence interval = 0.020-0.714) and longer sleeping sham-therapy group (odds ratio = 0.321; 95% confidence interval = 0.105-0.983) were also less likely to achieve insomnia and/or depression remission than was the longer sleeping CBT-I group with ≥ 5 hours of sleep.

CONCLUSIONS

Sleeping < 5 hours may dispose comorbid major depression/insomnia patients to a poor response to combined CBT-I/medication treatments for their insomnia and depression. Future studies to replicate these findings and explore mechanisms of treatment response seem warranted.

CLINICAL TRIAL REGISTRATION

Registry: ClinicalTrials.gov; Name: Treatment of Insomnia and Depression (TRIAD); URL: https://clinicaltrials.gov/ct2/show/results/NCT00767624; Identifier: NCT00767624.

CITATION

Edinger JD, Smith ED, Buysse DJ, et al. Objective sleep duration and response to combined pharmacotherapy and cognitive behavioral insomnia therapy among patients with comorbid depression and insomnia: a report from the TRIAD study. J Clin Sleep Med. 2023;19(6):1111-1120.

Racial disparities in treatment engagement and outcomes in digital cognitive behavioral therapy for insomnia among pregnant women

OBJECTIVES

In the United States, Black women are disproportionately afflicted with prenatal insomnia. Although cognitive-behavioral therapy for insomnia (CBTI) may represent a strategy to reduce disparities in insomnia, racial minorities attend fewer healthcare appointments and have poorer outcomes from prenatal care and mental health treatment relative to white patients. The present study examined differences in treatment engagement and patient-reported outcomes in non-Hispanic Black and white pregnant women receiving digital CBTI.

METHODS

Secondary analysis of 39 pregnant women with clinical insomnia who received digital CBTI. Treatment engagement was operationalized as the number of sessions completed (≥4 considered an adequate dose). Treatment outcomes were assessed using the Insomnia Severity Index (ISI; insomnia) and Pittsburgh Sleep Quality Index (PSQI; global sleep disturbance).

RESULTS

Black women were 4 times more likely than white women to discontinue CBTI before receiving an adequate dose (8.3% vs. 33.3%). Regarding treatment outcomes, white women reported a mean reduction of 5.75 points on the ISI and a reduction of 3.33 points on the PSQI (Cohen's dz = 1.10-1.19). By comparison, Black women reported reductions of 2.13 points on the ISI and 1.53 points on the PSQI, which were statistically non-significant. Differences in treatment engagement did not account for the disparities in patient-reported outcomes.

CONCLUSIONS

During pregnancy, Black women completed fewer CBTI sessions and experienced poorer treatment outcomes in response to digital CBTI relative to white women. Enhancements to insomnia therapy and its digital delivery may improve adherence and outcomes in Black pregnant women.

Cognitive-behavioral therapy for insomnia with objective short sleep duration phenotype: A systematic review with meta-analysis

Cognitive-behavioral therapy for insomnia (CBT-I) has been recommended as the first-line therapy for this condition. However, insomnia disorder with objective short sleep duration (ISS) phenotype is a distinct subtype from insomnia with normal sleep duration (INS) phenotype, and it may have a differential therapeutic response. We searched PubMed, EMBASE, Cochrane Library, and ClinicalTrials.gov using the PICOS principle for studies that examined the efficacy of cognitive-behavioral therapy for those with the ISS phenotype versus the INS phenotype, and identified nine studies with 612 patients with insomnia disorder. This included 270 patients with the ISS phenotype and 342 patients with the INS phenotype. The main outcome was that CBT-I had a better efficacy for the INS phenotype compared with the ISS phenotype, with about 30% higher response and about 20% higher remission. Similar results were indicated in the secondary outcomes. The therapeutic response of the ISS phenotype was significantly different from that of the INS phenotype. In the future, research is needed to clarify how to optimally treat insomnia disorder with the ISS phenotype in prospective randomized clinical trials, and to understand whether decreasing physiologic arousal will be necessary to improve results.

The underestimation of sleep duration phenotype is associated with better treatment response to cognitive behavior therapy for insomnia in patients with chronic insomnia: a preliminary study

STUDY OBJECTIVES

To examine treatment response to cognitive behavior therapy for insomnia (CBT-I) in patients with chronic insomnia with and without underestimation of sleep duration.

METHODS

We studied 41 patients with chronic insomnia who had received 5-week CBT-I. Self-reported and objective sleep were assessed with sleep diary and actigraphy, respectively. Sleep perception was calculated as self-reported total sleep time/objective total sleep time. The underestimation of sleep duration group was defined based on sleep perception less than the median of the overall sample (85%). Insomnia Severity Index was used to assess the severity of insomnia.

RESULTS

The total scores of Insomnia Severity Index decreased significantly after CBT-I in both groups with and without underestimation of sleep duration. Compared to pretreatment, self-reported sleep efficiency increased and total wake time decreased after CBT-I, while the magnitude of changes in sleep efficiency (d = 1.40 vs d=0.81, interaction P = .016) and total wake time (d = -1.82 vs d = -0.85, interaction P < .001) were larger in the underestimation of sleep duration group . Furthermore, self-reported sleep onset latency (interaction P = .520) and wake after sleep onset (interaction P = .052) decreased in the underestimation of sleep duration group (all P < .05), but not in patients without underestimation of sleep duration. Linear regressions showed that lower sleep perception at baseline predicted greater increase in self-reported sleep efficiency (β = -0.99, P < .001) and total sleep time (β = -0.51, P = .006) and greater decrease in self-reported total wake time (β=1.22, P = .023) after CBT-I after adjusting for confounders.

CONCLUSIONS

The current preliminary study suggests that sleep perception moderates the self-reported CBT-I effects on chronic insomnia: the phenotype of underestimation of sleep duration is associated with a better response to CBT-I, especially in self-reported sleep parameters.

CITATION

Sun Q, Dai Y, Chen B, et al. The underestimation of sleep duration phenotype is associated with better treatment response to cognitive behavior therapy for insomnia in patients with chronic insomnia: a preliminary study. J Clin Sleep Med. 2022;18(10):2443-2450.

Behavioral interventions for improving sleep outcomes in menopausal women: a systematic review and meta-analysis

IMPORTANCE

Perimenopausal and postmenopausal women commonly report sleep disruption and insomnia. Behavioral interventions may be safe alternatives for patients who are unwilling to begin pharmacological treatments because of adverse effects, contraindications, or personal preference.

OBJECTIVE

The primary objective is to assess the efficacy of behavioral interventions on sleep outcomes among perimenopausal and postmenopausal women, as measured using standardized scales and objective methods (polysomnography, actigraphy). The secondary objective is to evaluate the safety of these methods through occurrence of adverse events.

EVIDENCE REVIEW

Searches were performed within MEDLINE (OVID interface, 1946 onward), Embase (OVID interface, 1974 onward), Cochrane Central Register of Controlled Trials (CENTRAL), PubMed, and Web of Science (Core collection) using a search strategy developed in consultation with a health sciences librarian. Title/abstract and full-text screenings were performed in duplicate, and relevant studies were selected based on inclusion and exclusion criteria set to identify randomized controlled trials evaluating the effects of behavioral interventions on sleep quality. Risk of bias assessments were done using the Cochrane Risk of Bias 2 tool, and the Grading of Recommendations Assessment, Development and Evaluation approach was used to assess the certainty of the body of evidence. Data were pooled in a meta-analysis using a random-effects model.

FINDINGS

Nineteen articles reporting results from 16 randomized controlled trials were included, representing a total of 2,108 perimenopausal and postmenopausal women. Overall, behavioral interventions showed a statistically significant effect on sleep outcomes (standardized mean difference [SMD], -0.62; 95% confidence interval [CI], -0.88 to -0.35; I2 = 93.4%). Subgroup analyses revealed that cognitive behavioral therapy (SMD, -0.40; 95% CI, -0.70 to -0.11; I2 = 72.7%), physical exercise (SMD, -0.57; 95% CI, -0.94 to -0.21; I2 = 94.0%), and mindfulness/relaxation (SMD, -1.28; 95% CI, -2.20 to -0.37; I2 = 96.0%) improved sleep, as measured using both subjective (eg, Pittsburg Sleep Quality Index) and objective measures. Low-intensity (SMD, -0.91; 95% CI, -1.59 to -0.24; I2 = 96.8) and moderate-intensity exercise (SMD, -0.21; 95% CI, -0.34 to -0.08; I2 = 0.0%) also improved sleep outcomes. No serious adverse events were reported. Overall risk of bias ranged from some concern to serious, and the certainty of the body of evidence was assessed to be of very low quality.

CONCLUSIONS AND RELEVANCE

This meta-analysis provides evidence that behavioral interventions, specifically, cognitive behavioral therapy, physical exercise, and mindfulness/relaxation, are effective treatments for improving sleep outcomes among perimenopausal and postmenopausal women.

Connectomic disturbances underlying insomnia disorder and predictors of treatment response

Objective

Despite its prevalence, insomnia disorder (ID) remains poorly understood. In this study, we used machine learning to analyze the functional connectivity (FC) disturbances underlying ID, and identify potential predictors of treatment response through recurrent transcranial magnetic stimulation (rTMS) and pharmacotherapy.

Materials and methods

51 adult patients with chronic insomnia and 42 healthy age and education matched controls underwent baseline anatomical T1 magnetic resonance imaging (MRI), resting-stage functional MRI (rsfMRI), and diffusion weighted imaging (DWI). Imaging was repeated for 24 ID patients following four weeks of treatment with pharmacotherapy, with or without rTMS. A recently developed machine learning technique, Hollow Tree Super (HoTS) was used to classify subjects into ID and control groups based on their FC, and derive network and parcel-based FC features contributing to each model. The number of FC anomalies within each network was also compared between responders and non-responders using median absolute deviation at baseline and follow-up.

Results

Subjects were classified into ID and control with an area under the receiver operating characteristic curve (AUC-ROC) of 0.828. Baseline FC anomaly counts were higher in responders than non-responders. Response as measured by the Insomnia Severity Index (ISI) was associated with a decrease in anomaly counts across all networks, while all networks showed an increase in anomaly counts when response was measured using the Pittsburgh Sleep Quality Index. Overall, responders also showed greater change in all networks, with the Default Mode Network demonstrating the greatest change.

Conclusion

Machine learning analysis into the functional connectome in ID may provide useful insight into diagnostic and therapeutic targets.

Cognitive-behavioral, behavioural and mindfulness-based therapies for insomnia in menopause

OBJECTIVES

Insomnia is frequently reported by women during menopause due to physiological changes and environmental factors and is associated with negative daytime sequelae. Due to medication side effects and patient preferences, there is increased interest in the use of psychological treatments for menopausal insomnia. The primary objective of this review is to review the efficacy of cognitive-behavioral, behavioral, and mindfulness-based (CBBMB) therapies in treating insomnia in peri- and post-menopausal women. The secondary objective is to review the effect of CBBMB therapies on relevant secondary outcomes to gain a comprehensive understanding of their impacts.

METHODS

We conducted a narrative review of the literature. A search of PubMed and Google Scholar was conducted between January 2020 and March 2021.

RESULTS

Cognitive-behavioral therapy (CBT) for insomnia is efficacious, with corollary improvements in mood, functional outcomes and potential mechanistic factors (e.g., unhelpful beliefs). Sleep restriction therapy is also efficacious, with somewhat poorer effects on secondary outcomes relative to CBT. Mindfulness meditation and relaxation for insomnia demonstrated promise, but its long-term effects remain unknown.

CONCLUSIONS

Research with more diverse samples and head-to-head comparisons is needed. Dissemination of CBBMBs for insomnia in clinics where menopausal women seek care is an important next step.

Tailored individual Yoga practice improves sleep quality, fatigue, anxiety, and depression in chronic insomnia disorder

BACKGROUND

Chronic insomnia disorder (CI) is a prevalent sleep disorder that can lead to disturbed daytime functioning and is closely associated with anxiety and depression. First-choice treatment is cognitive behavioral therapy (CBT-I). Other mind-body interventions, such as Tai-chi and Yoga, have demonstrated subjective improvements in sleep quality. The purpose of this study was to assess the efficacy of Yoga for improvement of subjective and objective sleep quality as well as measures of anxiety, depression, sleepiness, and fatigue in patients with CI.

METHODS

Adults with CI were prospectively included in this single group pre-post study. Baseline assessments included home polysomnography (PSG), 7-day actigraphy, and questionnaires (Pittsburgh Sleep Quality Index questionnaire (PSQI), Hospital Anxiety Depression scale (HADS), Epworth Sleepiness Scale (ESS), Pichot fatigue scale (PS)). Patients practiced Viniyoga, an individualised Yoga practice with daily self-administered exercises, for 14 weeks. Assessments were repeated at the end of Yoga practice.

RESULTS

Twenty-one patients completed the study. Objective sleep measurements revealed no change in PSG parameters after Yoga practice, but a decrease in arousals on actigraphy (p < 0.001). Subjective symptoms improved for all questionnaires (PSQI, p < 0.001; HAD-A, p = 0.020, HAD-D, p = 0.001, ESS, p = 0.041, PS, p = 0.010). In univariate correlations, decrease in PSQI was associated with increase in sleep stage N3 (p < 0.001) on PSG.

CONCLUSIONS

We have demonstrated a positive impact of individualized Yoga practice on subjective parameters related to sleep and daytime symptoms in CI, resulting in fewer arousals on actigraphy. Yoga could be proposed as a potentially useful alternative to CBT-I in CI, as it is easy to practice autonomously over the long-term. However, given the design of the present study, future prospective controlled studies should first confirm our results.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT03314441 , date of registration: 19/10/2017.

Insomnia with objective short sleep duration in women with temporomandibular joint disorder: quantitative sensory testing, inflammation and clinical pain profiles

OBJECTIVES/BACKGROUND

Temporomandibular joint disorder (TMD) is a disabling facial pain syndrome with a high prevalence of insomnia that primarily affects women. Insomnia with objective short sleep duration (ISSD) is an emerging phenotype linked to cardiometabolic morbidity and increased mortality. The present report examines the association of ISSD on clinical and laboratory pain and systemic inflammation in TMD.

METHODS

We collected baseline data from 128 women with TMD and insomnia as part of a clinical trial evaluating psychological interventions for sleep and pain. Participants completed self-report questionnaires, one-night polysomnography, a two-week actigraphy assessment, quantitative sensory testing (QST) to assess cold pain tolerance, pain sensitivity and central sensitization and circulating Interleukin-6 levels were measured to assess systemic inflammation.

RESULTS

24.2% (n = 31) of the sample met criteria for ISSD [polysomnography (sleep duration <6 h)]. Compared to those with insomnia and normal sleep duration, ISSD were older (40.4 vs. 34.9,p < 0.05) and a greater proportion self-identified as Black (48.4% vs 11.3%,p < 0.001). Multivariate regressions revealed that ISSD endorsed higher self-report pain severity and functional limitation of the jaw. ISSD also demonstrated increased generalized pain sensitivity, enhanced central sensitization, cold pressor tolerance and higher resting interleukin-6 levels.

CONCLUSIONS

This is the first study to characterize the ISSD phenotype in a chronic pain sample and expand the scope of its negative health outcomes to chronic pain. ISSD may be an important chronic pain phenotype associated with a more severe clinical and laboratory pain profile, and future studies should focus on implications for treatment response and disease trajectory.

CLINICAL TRIAL

ClinicalTrials.gov Identifier: NCT01794624.

Association between insomnia patients' pre-treatment characteristics and their responses to distinctive treatment sequences

STUDY OBJECTIVES

It is common to provide insomnia patients a second treatment when the initial treatment fails, but little is known about optimal treatment sequences for different patient types. This study examined whether pre-treatment characteristics/traits predict optimal treatment sequences for insomnia patients.

METHODS

A community sample of 211 adults (132 women; Mage = 45.6 ± 14.9 years) with insomnia were recruited. Patients were first treated with behavioral therapy (BT) or zolpidem (Zol). Non-remitting BT recipients were randomized to a second treatment with either Zol or cognitive therapy; non-remitting Zol recipients underwent BT or Trazodone as a second treatment. Remission rates were assessed at the end of the first and second 6-week treatments. We then compared the remission rates of dichotomous groups formed on the basis of gender, age, pretreatment scores on SF36 and Multidimensional Fatigue Scale, the presence/absence of psychiatric/medical comorbidities or pain disorders, and mean subjective sleep duration and efficiency within and across treatment sequences.

RESULTS

Lower remission rates were noted for those: with a pain disorder, poor mental health perceptions, high MFI fatigue scores, and lower sleep times and efficiencies. Patients with a pain disorder responded best to the BT-to-Zol sequence, whereas patients with more mental impairment, severe fatigue, short sleep, and low sleep efficiency responded poorly to treatment starting with BT.

CONCLUSIONS

Pain, fatigue, poor mental health status, and subjective sleep duration and efficiency all affect response to different insomnia treatment sequences. Findings may guide clinicians in matching insomnia treatments to their patients.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT01651442, Protocol version 4, April 20, 2011, registered June 26, 2012, https://clinicaltrials.gov/ct2/show/NCT01651442?rslt=With&type=Intr&cond=Insomnia&cntry=US&state=US%3ACO&city=Denver&age=12&draw=2&rank=1.

Randomized controlled trial of digital cognitive behavior therapy for prenatal insomnia symptoms: Effects on postpartum insomnia and mental health

STUDY OBJECTIVES

To evaluate the effects of digital cognitive behavior therapy for insomnia (dCBT-I) delivered during pregnancy on subjective sleep outcomes, depressive symptoms, and anxiety symptoms through six months postpartum.

METHODS

People up to 28 weeks gestation (N=208) with insomnia were randomized to six weekly sessions of dCBT-I or standard care. We report follow-up data at three and six months postpartum. The primary outcome was insomnia symptom severity. Secondary sleep outcomes included global sleep quality and insomnia caseness. Mental health outcomes included depressive and anxiety symptom severity. We evaluated between-condition differences in change from baseline for each postpartum timepoint and categorical outcomes.

RESULTS

dCBT-I participants did not experience significantly greater improvements in insomnia symptom severity relative to standard care participants, but they did experience higher rates of insomnia remission and lower rates of insomnia caseness at six months postpartum. dCBT-I participants experienced greater improvements in depressive symptom severity from baseline to both postpartum timepoints, and in anxiety symptom severity from baseline to three months postpartum. The proportion of participants with probable major depression at three months postpartum was significantly higher among standard care (18%) than dCBT-I (4%, p=.006) participants; this between-condition difference was pronounced among the subset (n=143) with minimal depressive symptoms at baseline (18% vs 0%).

CONCLUSION

dCBT-I use during pregnancy leads to enduring benefits for postpartum insomnia remission. Findings provide strong preliminary evidence that dCBT-I use during pregnancy may prevent postpartum depression and anxiety, which is notable when considering the high frequency and importance of these problems.

Impact of daytime sleepiness and insomnia on simple and complex cognitive task performances

OBJECTIVE

To examine the individual and combined effects of daytime sleepiness and insomnia disorder (ID) on measures of cognitive functioning.

DESIGN AND SETTING

This study was conducted at a medical center using a cross-sectional research design.

PARTICIPANTS

35 persons with ID (Mage = 40.6 years; 25 women) and 54 normal sleepers (NS; Mage = 31.5 years; 38 women).

METHODS AND MEASURES

Participants underwent two nights of home-based polysomnography (PSG) followed by daytime testing with a four-trial Multiple Sleep Latency Test (MSLT). Before each MSLT nap, they completed a computer-administered battery of reaction time tasks. Measures of response latencies and response accuracy were tabulated and used as dependent measures. The ID and NS groups were each subdivided into "alert" (eg, MSLT mean latency > 8 min) and "sleepy" (eg, MSLT mean latency ≤ 8 min) subgroups to identify hyperaroused persons with ID and allow for their comparisons with the other participant subgroups.

RESULTS

Multivariate analyses of variance showed a significant main effect for level of daytime sleepiness (F [1, 84] = 8.52, p = 0.0045) on simpler performance tasks and a significant main effect for presence vs. absence of ID (F [1,84] = 6.62, p = 0.012) on complex tasks. A lack of significant participant type x MSLT alertness level interactions in study analyses suggested those ID participants with presumed hyperaousal were not relatively more impaired than the other participant subgroups.

CONCLUSIONS

Daytime performance deficits on simple tasks seem most dependent on individuals' levels of daytime sleepiness, whereas performance deficits on more complex tasks appears related to the presence of ID. Therefore, it seems best to use complex performance measures both to document cognitive deficits among those with ID and to determine if insomnia treatments reduce such impairments.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02290405.

Polysomnographic Predictors of Treatment Response to Cognitive Behavioral Therapy for Insomnia in Participants With Co-morbid Insomnia and Sleep Apnea: Secondary Analysis of a Randomized Controlled Trial

OBJECTIVE

Co-morbid insomnia and sleep apnea (COMISA) is a common and debilitating condition that is more difficult to treat compared to insomnia or sleep apnea-alone. Emerging evidence suggests that cognitive behavioral therapy for insomnia (CBTi) is effective in patients with COMISA, however, those with more severe sleep apnea and evidence of greater objective sleep disturbance may be less responsive to CBTi. Polysomnographic sleep study data has been used to predict treatment response to CBTi in patients with insomnia-alone, but not in patients with COMISA. We used randomized controlled trial data to investigate polysomnographic predictors of insomnia improvement following CBTi, versus control in participants with COMISA.

METHODS

One hundred and forty five participants with insomnia (ICSD-3) and sleep apnea [apnea-hypopnea index (AHI) ≥ 15] were randomized to CBTi (n = 72) or no-treatment control (n = 73). Mixed models were used to investigate the effect of pre-treatment AHI, sleep duration, and other traditional (AASM sleep macrostructure), and novel [quantitative electroencephalography (qEEG)] polysomnographic predictors of between-group changes in Insomnia Severity Index (ISI) scores from pre-treatment to post-treatment.

RESULTS

Compared to control, CBTi was associated with greater ISI improvement among participants with; higher AHI (interaction p = 0.011), less wake after sleep onset (interaction p = 0.045), and less N3 sleep (interaction p = 0.005). No quantitative electroencephalographic, or other traditional polysomnographic variables predicted between-group ISI change (all p > 0.09).

DISCUSSION

Among participants with COMISA, higher OSA severity predicted a greater treatment-response to CBTi, versus control. People with COMISA should be treated with CBTi, which is effective even in the presence of severe OSA and objective sleep disturbance.