Objective Sleep Parameters Research Articles

Light Therapy in Post-Traumatic Stress Disorder: A Systematic Review of Interventional Studies.

Background: Due to limitations in treatment strategies for post-traumatic stress disorders (PTSD), therapeutic options such as light therapy (LT) have garnered some interest in recent years. We aimed to review the effectiveness of LT in patients with PTSD. Methods: Using PubMed, PsycINFO, Web of Science, the Cochrane database, ClinicalTrials.gov, and PTSDpubs, we systematically searched for papers assessing the effect of LT in PTSD. We evaluated the risk of bias of included studies using the Cochrane handbook, and synthesized our findings following the Preferred Reporting Items for Systematic reviews and Meta-Analyses guidelines (PRISMA 2020). Results: From 140 initial papers, we included four randomized controlled trials (RCTs) and one single-arm study. The study sample size ranged between 15 and 82, the mean age (standard deviation) varied between 31.4 (8.8) and 44.9 (11.8) years, and LT was applied for four or six weeks. The risk of bias was low in three studies, and of some concern in the two other trials. Most studies reported no significant differences between LT and placebo regarding effects on subjective (sleep quality and insomnia severity) and objective sleep parameters. LT was associated with a significant improvement in PTSD symptom severity in the single-arm study and two RCTs, as well as a greater retention of extinction learning. Results on depression and anxiety were discrepant. Conclusions: This review revealed that relevant studies are scarce, with promising findings concerning PTSD symptoms, but inconsistencies for the other parameters. Further research projects are needed to better explore this topic.

The impact of forced awakening on morning blood pressure surge

BackgroundPoor sleep quality can cause an increase in morning blood pressure surge (MBPS), an independent risk factor of cardiovascular disease (CVD) events. Awakening induced by external factors such as alarm clocks, may also contribute to increased MBPS. ObjectivesTo (1) compare the MBPS and sleep quality parameters between natural and forced awakenings and (2) examine the potential impact of forced awakening on MBPS, independent of sleep quality. MethodsThirty-two healthy adults participated in this pilot study, which included one night of natural awakening and one night of forced awakening (i.e., sleep was interrupted by an alarm after five hours). Objective and self-reported sleep quality parameters were measured using a multisensory wristband and sleep diaries, respectively, and beat-to-beat blood pressure variability was assessed using a continuous blood pressure monitor. Analyses included a paired t-test (objective 1) and linear mixed models (objective 2). ResultsParticipants predominantly consisted of young, healthy, and highly educated Asian adults. During the night of sleep with forced awakening, significantly higher MBPS, lower objective wakefulness after sleep onset, and lower self-reported sleep latency were observed, compared to the night with natural awakening. Forced awakening was significantly associated with increased MBPS after controlling for age, sex, mean arterial pressure, and sleep quality. ConclusionsForced awakening may significantly increase MBPS, consequently heightening the risk of CVD events. Study findings should be validated in a larger sample. Further research is also warranted to examine the impact of forced awakening on MBPS in individuals with CVD.

Therapeutic sleep deprivation for major depressive disorder: A randomized controlled trial

BackgroundMajor depressive disorder (MDD) is treated primarily using antidepressant drugs, but clinical effects may be delayed for weeks to months. This study investigated the efficacy of brief therapeutic sleep deprivation (TSD) for inducing rapid improvements in MDD symptoms. MethodsFrom November 2020 to February 2023, 54 inpatients with MDD were randomly allocated to TSD and Control groups. The TSD group (23 cases) remained awake for 36 h, while the Control group (31 cases) maintained regular sleep patterns. All participants continued regular drug therapy. Mood was assessed using the 24-item Hamilton Depression Scale (HAMD-24) at baseline and post-intervention in both groups. In the TSD group, the Visual Analogue Scale (VAS) was utilized to evaluate subjective mood during and after the intervention. Cognitive function was assessed at baseline and post-intervention using the Montreal Cognitive Assessment (MoCA). Objective sleep parameters were recorded in the TSD group by polysomnography. The follow-up period spanned one week. ResultsHAMD-24 scores did not differ between groups at baseline or post-intervention. However, the clinical response rate was 34.8 % higher in the TSD group on day 3 post-intervention compared to the Control group (3.2 %), but not sustained by day 7. Moreover, responders demonstrated a faster improvement in the VAS score during TSD than non-responders (p = 0.047). There were no significant differences in MoCA scores or objective sleep parameters between the groups. LimitationsSmall sample size and notable attrition rate. ConclusionsTherapeutic sleep deprivation can rapidly improve MDD symptoms without influencing sleep parameters or cognitive functions. Assessment of longer-term effects and identification of factors predictive of TSD response are warranted.

Executive function performance in children and adolescent patients with narcolepsy type 1

ObjectiveThe executive function profile in patients with narcolepsy type 1 (NT1) has been mentioned; however, limited research exists on children and adolescent patients with NT1.This study aims to assess executive function in children and adolescent patients with NT1 in China, examine potential influencing factors and evaluate the short-term treatment effect on executive function. Methods53 NT1 patients (36 males, age 12.2 ± 3.4 years) and 37 healthy controls (23 males, age 12.2 ± 2.5 years) underwent self-reported measures assessing subjective sleepiness, depression, anxiety and sleep quality. A comprehensive neuropsychological test was administered to assess executive function domains, including processing speed, inhibitory control, cognitive flexibility and working memory. These assessments were repeated in NT1 patients after three-day regular drug treatment. ResultsNT1 patients exhibited higher levels of excessive daytime sleepiness, depression, anxiety, and poor sleep quality compared to healthy controls. Patients showed impaired processing speed, inhibitory control and cognitive flexibility (p < 0.05), whereas working memory was unaffected (p > 0.05). Regression analysis revealed that parameters from sleep monitoring, such as sleep efficiency and sleep latency, were correlated with executive function performance after controlling for age, gender, and education years. The short-term treatment led to improvements in inhibitory control, cognitive flexibility, and working memory. ConclusionThe findings showed that executive function was impaired among children and adolescent patients with NT1, which was associated with objective sleep parameters. Furthermore, this study emphasizes the necessity of neuropsychological assessments and early interventions among children and adolescent NT1 patients.

Identification of sleep phenotypes in COPD using machine learning-based cluster analysis

BackgroundDisturbed sleep in patients with COPD impact quality of life and predict adverse outcomes. Research questionTo identify distinct phenotypic clusters of patients with COPD using objective sleep parameters and evaluate the associations between clusters and all-cause mortality to inform risk stratification. Study design and methodsA longitudinal observational cohort study using nationwide Veterans Health Administration data of patients with COPD investigated for sleep disorders. Sleep parameters were extracted from polysomnography physician interpretation using a validated natural language processing algorithm. We performed cluster analysis using an unsupervised machine learning algorithm (K-means) and examined the association between clusters and mortality using Cox regression analysis, adjusted for potential confounders, and visualized with Kaplan-Meier estimates. ResultsAmong 9992 patients with COPD and a clinically indicated baseline polysomnogram, we identified five distinct clusters based on age, comorbidity burden and sleep parameters. Overall mortality increased from 9.4 % to 42 % and short-term mortality (<5.3 years) ranged from 3.4 % to 24.3 % in Cluster 1 to 5. In Cluster 1 younger age, in 5 high comorbidity burden and in the other three clusters, total sleep time and sleep efficiency had significant associations with mortality. InterpretationWe identified five distinct clinical clusters and highlighted the significant association between total sleep time and sleep efficiency on mortality. The identified clusters highlight the importance of objective sleep parameters in determining mortality risk and phenotypic characterization in this population.

Polysomnographic parameters associated with cognitive function in patients with major depression and insomnia.

To examine whether objective sleep parameters are associated with cognitive function (CF) in patients with major depressive disorder (MDD) with chronic insomnia (CI) and whether the severity of these disorders is related to CF. Thirty patients with MDD with CI attending a tertiary care institution underwent two consecutive nights of polysomnographic (PSG) recording and a battery of neuropsychological tests, which included episodic memory, sustained attention, working memory, and executive function. The severity of MDD and CI was assessed by clinical scales. We examined the relationship between PSG parameters and CF, as well as whether the severity of the disorders is related to CF. Linear regression analysis revealed that total sleep time (TST) was positively associated with higher learning and recall of episodic memory, as well as better attention. Slow-wave sleep (SWS) showed a positive association with better working memory. Furthermore, wake after sleep onset (WASO) was negatively associated with episodic memory and lower attention. No significant relationships were found between the severity of MDD or CI with CF. Both sleep duration and depth are positively associated with several aspects of CF in patients with MDD with CI. Conversely, a lack of sleep maintenance is negatively related to CF in these patients. These findings could help identify modifiable therapeutic targets to reduce CF impairment.

Subjective sleep more predictive of global cognitive function than objective sleep in older adults: A specification curve analysis

ObjectivesSleep is associated with cognitive function in older adults. In the current study, we examined this relationship from subjective and objective perspectives, and determined the robustness and dimensional specificity of the associations using a comprehensive modelling approach. MethodsMultiple dimensions of subjective (sleep quality and daytime sleepiness) and objective sleep (sleep stages, sleep parameters, sleep spindles, and slow oscillations), as well as subjectively reported and objectively measured cognitive function were collected from 55 older adults. Specification curve analysis was used to examine the robustness of correlations for the effects of sleep on cognitive function. ResultsRobust associations were found between sleep and objectively measured cognitive function, but not with subjective cognitive complaints. In addition, subjective sleep showed robust and consistent associations with global cognitive function, whereas objective sleep showed a more domain-specific association with episodic memory. Specifically, subjective sleep quality and daytime sleepiness correlated with global cognitive function, and objective sleep parameters correlated with episodic memory. ConclusionsOverall, associations between sleep and cognitive function in older adults depend on how they are measured and which specific dimensions of sleep and domains of cognitive function are considered. It highlights the importance of focusing on specific associations to ameliorate the detrimental effects of sleep disturbance on cognitive function in later life.

0889 Association of U.S. Military Burn Pit Smoke Exposure with Objective Sleep Parameters Among Smoking Veterans

0889 Association of U.S. Military Burn Pit Smoke Exposure with Objective Sleep Parameters Among Smoking Veterans

Effect of a nutraceutical combination on sleep quality among people with impaired sleep: a randomised, placebo-controlled trial

In this randomised, placebo-controlled trial, adults with impaired sleep (Pittsburgh Sleep Quality Index ≥ 5) were randomly assigned using a minimization algorithm to receive a formulation containing l-theanine plus lemon balm, valerian, and saffron extracts, or placebo, during 6 weeks. Objective sleep quality parameters were measured using an actigraphy device. We enrolled and randomised 64 individuals, 31 from the active group and 27 from the placebo group completed the 6 week follow-up. Mean sleep efficiency remained unmodified in the active group, and increased by 3% in the placebo group, the between-group difference in the change was not statistically significant (p = 0.49). Total sleep time also improved more with placebo (13.0 vs. 1.33 min, p = 0.66). Time wake after sleep onset (WASO) decreased more in the active group (4.6% vs. 2.4%), but the difference was not significant (p = 0.33). Mean PSQI decreased by 3.11 points (32.3%) in the active group, and by 3.86 points (39.5%) in the placebo group (p = 0.41). SF-36 increased more with placebo (+ 18.3 in active, + 32.1 in placebo, p = 0.68). Salivary cortisol remained unchanged in both groups. No serious adverse events were reported. Among adults with impaired sleep, a nutraceutical combination did not improve objective or subjective sleep parameters more than a placebo infusion.

346 Multimodal assessment of sleep in individuals with chronic post-concussive symptoms: A Pilot Study

OBJECTIVES/GOALS: Weaimed to compare subjective and objective sleep in individuals with chronic post-concussive symptoms. We hypothesized an association between self-reported sleep quality and objective sleep parameters, which is different for concussed and control cohorts. METHODS/STUDY POPULATION: 28 individuals with chronic post-concussive symptoms and 13 age-matched controls (no concussion history) completed the ISI, PSQI, PROMIS Depression, Anxiety, Stress and Cognitive questionnaires at enrollment. Objective sleep parameters were obtained for a minimum of 7 days and up to 30 days with a validated sleep monitoring device placed under the subject’s bed (Emfit). For each night, raw activity data per minute were analyzed to determinein-bed, sleep, wake, andout-of-bedtimes. These measures were used to calculate total sleep time (TST), sleep onset latency (SOL), and wake after sleep onset (WASO) for each night. RESULTS/ANTICIPATED RESULTS: Concussed individuals reported worse sleep with PSQI and ISI scores significantly higher than controls. They also showedsignificant associations between PSQI and Dep ression, ISI and Depression, and ISI and Anxiety scores. There was no difference between objective sleep parameters in the concussed and control cohorts (in-bed/sleep/wake/out-of-bed times, TST, SOL, and WASO). Instead, higher PSQI, ISI, Depression, Anxiety, and Stress scores (greater symptom burden) were all associated with later sleep times, where as higher Cognitive scores (greater cognitive function) were associated with earlier sleep times, regardless of group status. DISCUSSION/SIGNIFICANCE: Concussed individuals report worse subjective sleep but no differences to controls when objectively assessing sleep. Depression/anxiety, and not concussion status, determine objective sleep parameters. Psychiatric comorbidities should inform the treatment of post-concussive sleep disturbances.

Harnessing technology to improve sleep in frontline healthcare workers: A pilot study of electronic noise-masking earbuds on subjective and objective sleep measures.

Objective: This pilot study assessed the effects of electronic noise-masking earbuds on subjective sleep perception and objective sleep parameters among healthcare workers (HCWs) reporting sleep difficulties during the COVID-19 pandemic. Methods: Using a pre-post design, 77 HCWs underwent 3 nights of baseline assessment followed by a 7-night intervention period. Participants wore an at-home sleep monitoring headband to assess objective sleep measures and completed subjective self-report assessments. The difference in mean sleep measures from baseline to intervention was estimated in linear mixed models. Results: Compared to baseline assessments, HCWs reported significant improvements in sleep quality as measured by the Insomnia Severity Index (ISI) (Cohen's d = 1.74, p < 0.001) and a significant reduction in perceived sleep onset latency (SOL) during the intervention (M = 17.2 minutes, SD = 7.7) compared to baseline (M = 24.7 minutes, SD = 16.1), (Cohen's d = -0.42, p = 0.001). There were no significant changes in objective SOL (p = 0.703). However, there was a significant interaction between baseline objective SOL (<20 minutes vs >20 minutes) and condition (baseline vs intervention) (p = 0.002), such that individuals with objective SOL >20 minutes experienced a significant decrease in objective SOL during the intervention period compared to baseline (p = 0.015). Conclusions: HCWs experienced a significant improvement in perceived SOL and ISI scores after using the electronic noise-masking earbuds. Our data provide preliminary evidence for a nonpharmacological intervention to improve the sleep quality of HCWs which should be confirmed by future controlled studies.

Elevated pain sensitivity is associated with reduced rapid eye movement (REM) sleep in females with comorbid temporomandibular disorder and insomnia.

Patients with chronic pain disorders, including Temporomandibular Disorders (TMDs) endorse high levels of sleep disturbances, frequently reporting reduced sleep quality. Despite this, little is known about the effect that daytime pain has on the microstructure and macro-architecture of sleep. Therefore, we aimed to examine the extent to which daytime pain sensitivity, measured using quantitative sensory testing (QST), is associated with objective sleep parameters the following night, including sleep architecture and power spectral density, in women with TMD. 144 females with myalgia and arthralgia by examination using the Diagnostic criteria for TMD completed a comprehensive QST battery consisting of General Pain Sensitivity, Central Sensitization Index, and Masseter Pressure Pain Threshold assessments. Polysomnography was collected the same night to measure sleep architecture and calculate relative power in delta, theta, alpha, sigma, and beta power bands. Central Sensitization (B = -3.069, P = .009), General Pain Sensitivity Indices (B = -3.069, P = .007), and Masseter Pain Pressure Threshold (B = 0.030, P = .008) were significantly associated with lower REM% both before and after controlling for covariates. Pain sensitivity measures were not significantly associated with relative power in any of the spectral bands nor with any other sleep architectural stages. Our findings demonstrate that higher generalized pain sensitivity, masseter pain pressure threshold, as well as central sensitization were associated with a lower percentage of REM in participants with myofascial pain and arthralgia of the masticatory system. These findings provide an important step toward understanding the mechanistic underpinnings of how chronic pain interacts with sleep physiology.

Sleep behavior after reverse shoulder replacement in comparison to a healthy control group : An exploratory cross-sectional study

Individuals with shoulder pathologies frequently report sleep problems. Improving sleep quality is atreatment focus of shoulder arthroplasty. So far, it is unclear whether altered anatomy and biomechanics in reversed total shoulder arthroplasty affect sleep quality in the long term. In addition to asubjective evaluation, areliable assessment can be obtained by recording objective sleep parameters. With the help of actigraphy, body movements are registered and divided into active and inactive phases by means of threshold values. Thanks to the valid correspondence with waking and sleeping phases, the calculation of objective sleep parameters is successful. The aims of the study were to investigate whether objective sleep parameters differ in persons with reversed total shoulder arthroplasty (RTSA) 1 year postoperatively compared to ahealthy control group and to explore what the reasons are. The present work is an exploratory cross-sectional study with one measurement time point. 29study participants (15 in the RTSA-group, 14in the control group) collected objective sleep parameters and body position data during seven nights using actigraphy. The Mann-Whitney-U test was used for the mean comparison of sleep parameters. In addition, reasons for wakefulness were explored. The groups showed no significant differences in all objective sleep parameters with nearly identical sleep efficiency (p = 0.978). In the RTSA-group, 11% lay on the operated side and 65% on the back. This is just above the significance level compared to the control group with 45% in the supine position (p = 0.056). The increased use of the supine position could promote sleep-related medical conditions such as sleep apnoea and requires further research.

Physical activity in the treatment of primary insomnia

Insomnia is commonplace in the general population. Poor sleep quality leads to various health dysfunctions and compromises the well-being of the affected individuals. Non-pharmacologic approaches should be considered the first-line treatment as suggested by various guidelines. Among others (e.g., sleep hygiene, cognitive-behavioral therapy, light therapy), appropriate physical activity seems to be promising in treating and preventing sleep disturbance development. We found that improvement in a particular objective and subjective sleep quality parameters may be attributed to appropriate physical activity. When further analyzing the activity, lightintensity aerobic exercises and resistance training reduced insomnia symptoms. High-intensity interval training also showed a positive effect on the improvement in depressive symptoms. Regarding mind-body practices, current evidence is insufficient to conclude. However, it was documented that stress, depression, and anxiety reduction, can improve well-being.

The Relationship between Sleep Parameters Measured by Polysomnography and Selected Neurotrophic Factors.

The molecular underpinnings of insufficient sleep remain underexplored, with disruptions in the neurotrophic signaling pathway emerging as a potential explanation. Neurotrophins (NTs), including brain-derived neurotrophic factor (BDNF), neurotrophin-3 (NT3), neurotrophin 4 (NT4), and glial-cell-line-derived growth factor (GDNF), play crucial roles in nerve cell growth and repair. However, their associations with sleep patterns are poorly understood. This study aimed to investigate the relationship between the chosen neurotrophins and objective sleep parameters. The study involved 81 participants subjected to polysomnography (PSG). Blood samples were collected after PSG. The mRNA expression and serum protein concentrations of BDNF, GDNF, NT3, and NT4 were measured using real-time quantitative reverse-transcription PCR (qRT-PCR) or enzyme-linked immunosorbent assay (ELISA) methods, respectively. BDNF and NT3 proteins were negatively correlated with NREM events, while NT4 protein positively correlated with REM events. Electroencephalography power analysis revealed BDNF protein's negative correlation with delta waves during rapid eye movement and non-rapid eye movement sleep. The study highlights associations between neurotrophins and sleep, emphasizing BDNF's role in regulating NREM and REM sleep. The EEG power analysis implicated BDNF in delta wave modulation, shedding light on potential neurotrophic mechanisms underlying sleep effects on cognitive and mood processes.

Association of self-reported and objective sleep disturbance with the spectrum of gastroesophageal reflux disease.

The relationship between obstructive sleep apnea (OSA) and gastroesophageal reflux disease (GERD) is complex. We aimed to determine the association of self-reported and objective sleep parameters with diverse manifestations of the GERD spectrum. We prospectively recruited 561 individuals who underwent an electrocardiogram-based cardiopulmonary coupling for OSA screening during a health check-up. All participants received the Reflux Disease Questionnaire and an upper endoscopy to determine the presence of troublesome reflux symptoms and erosive esophagitis (EE). Sleep quality was evaluated by the Pittsburgh Sleep Quality Index and sleep dysfunction was defined as a Pittsburgh Sleep Quality Index score > 5. OSA was defined as a cardiopulmonary coupling-derived apnea-hypopnea index exceeding 15 events/h. Comparisons were made between participants on the GERD spectrum with respect to their various self-reported and objective sleep parameters. Among the 277 patients with GERD (49.4%), 198 (35.3%) had EE. Patients with GERD had higher PSQI scores (6.99 ± 3.97 vs 6.07 ± 3.73, P = .005) and a higher prevalence of sleep dysfunction (60.6% vs 49.6%, P = .009). Patients with EE had a higher prevalence of OSA (42.9% vs 33.9%, P = .034). Along the GERD spectrum, symptomatic patients with EE had the highest PSQI scores and prevalence of sleep dysfunction (70.7%), while asymptomatic patients with EE had the highest prevalence of OSA (44%). Our findings indicate a high prevalence of sleep dysfunction among individuals with GERD. Furthermore, patients on the GERD spectrum are prone to experiencing a range of self-reported and objective sleep disturbances. Hu K-Y, Tseng P-H, Hsu W-C, etal. Association of self-reported and objective sleep disturbance with the spectrum of gastroesophageal reflux disease. J Clin Sleep Med. 2024;20(6):911-920.

Associations between objective sleep parameters and brain amyloid-β burden in non-demented populations: a meta-analysis

Associations between objective sleep parameters and brain amyloid-β burden in non-demented populations: a meta-analysis

Sleep and Caregiver Burden Among Caregivers of Persons Living With Dementia: A Scoping Review.

Caregivers of persons with dementia report worse sleep when compared to the general population. The objective of this review was to synthesize evidence regarding the link between caregiver burden and dementia caregivers' sleep. We conducted a scoping review using a systematic search for pertinent literature in PubMed, CINAHL, and Web of Science through March 2022. Keywords included content areas of dementia, caregiver burden, and sleep. Inclusion criteria were informal caregivers of persons living with dementia, a measured relationship between informal dementia caregiver sleep and subjective caregiver burden variables, and original research. Non-English studies were excluded. Extracted data were organized in tables, compared, and synthesized. The search yielded 540 nonduplicate articles screened by title and abstract; 118 full-text articles were reviewed; 24 were included. Most studies were cross-sectional, with variable sample sizes. Dementia caregivers had significantly poorer overall perceived sleep than noncaregivers across 4 studies that examined self-reported sleep measures. Eighteen studies investigated the association between caregiver burden and self-reported sleep quality, with 14 reporting a significant positive association between caregiver burden and self-reported sleep quality, and 4 finding null results. Only 2 of the 4 studies reporting the association between caregiver burden and objective sleep parameters (ie, actigraphy and polysomnography) reported a significant positive association for at least one sleep subdomain. Although subjective sleep quality is commonly affected by dementia caregiving burden, there is a lack of corresponding evidence on the relationship between burden and objective sleep metrics. Healthcare providers should consider the dementia caregiver burden's impact on sleep and regularly assess caregivers' sleep difficulties. Future studies should focus on consistently measuring caregiver burden and sleep to promote dementia caregiver health and well-being.

Subjective sleep onset latency is influenced by sleep structure and body heat loss in human subjects.

The present study examined the relationship between subjective sleep onset latency (SOL), sleep structure, changes in skin and body temperature, and subjective evaluation of sleep in healthy young adults to elucidate the pathophysiological mechanisms of insomnia. A total of 28 participants (age 21.54 [0.50] years) with no sleep problems participated in a 1-h polysomnographic recording that obtained objective sleep parameters during the daytime while skin and body temperatures were recorded. The distal-proximal skin temperature gradient (DPG) was calculated. Subjective parameters, such as subjective SOL, sleep time, and restorative sleepiness, were evaluated before and after sleep. Most participants estimated their sleep latency as being longer than their actual SOL (13.7 versus 7.6 min). Objective SOL was significantly correlated with each sleep stage parameter whereas subjective SOL was negatively correlated with Stage N2 sleep duration (Rho = -0.454, p = 0.020), slow-wave activity and delta power (Rho = -0.500, p = 0.011 and Rho = -0.432, p = 0.031, respectively), and ΔDPG (the degree of reduction of heat loss before and after lights-off). Stepwise regression analysis showed that ΔDPG was the strongest predictive factor in explaining the length of subjective SOL. The degree of heat dissipation before and after lights-off contributed most to the sensation of falling asleep in healthy young adults. This finding may be helpful for elucidating the physiological mechanisms of insomnia and its treatment.

Cognitive Behavioural Therapy for insomnia decreases the discrepancy between objective and subjective measures of sleep.

Individuals with insomnia disorder often exhibit differences between reported experiences of sleep and objectively measured sleep parameters; however, the implications of this subjective-objective sleep discrepancy during treatment remains unclear. The aim of this study was to investigate the impact of cognitive behavioural therapy for insomnia (CBT-I) on the discrepancy between objective and subjective measures of sleep, and to assess whether changes in clinical variables such as depression, anxiety, fatigue, and beliefs about sleep, were related to changes in discrepancy. Twenty-five participants with insomnia disorder were enrolled in group CBT-I. Sleep measures were continually sampled from baseline until 2 weeks post-treatment with both objective (i.e., actigraphy) and subjective (i.e., sleep diary) methods. The subjective-objective discrepancy significantly decreased from baseline early on in treatment (following the second session) and were maintained at post-treatment for sleep onset latency, wake after sleep onset (WASO) and sleep efficiency (SE). Total sleep time (TST) discrepancy and misperception decreased from baseline to post-treatment. Improvement in depression symptoms, fatigue symptoms, and negative beliefs about sleep were significantly correlated with the decrease in the discrepancy for WASO and SE. These findings suggest that CBT-I resolves the mismatch between objective and subjective sleep parameters early in treatment for adults with insomnia. Sleep misperception improved from underestimating to accurately estimating TST. Improvement of psychological symptoms were related to decrease in sleep discrepancies across treatment. Future research is needed to explore how feedback on objective and subjective sleep discrepancy may impact sleep perception across treatment with CBT-I.