Prevalence and risk factors of sleep disturbances in breast cancersurvivors: systematic review and meta-analyses.

BACKGROUND: Breast cancer remains the most frequently diagnosed malignancy among women worldwide, with rising incidence numbers. In Belgium, one out of eight women will be diagnosed with breast cancer. Fortunately, 80% of those breast cancer patients will still be alive 10 years after diagnosis due to improvements in screening and treatment strategies. However, an important portion of the breast cancer survivors (BCS) will face side effects, such as sleep disturbances, long after treatment ends. It has been demonstrated that untreated insomnia in BCS negatively impacts mood, physical symptoms, pain sensitivity, fatigue, and quality of life. Furthermore, insomnia is increasingly considered an independent risk factor for future depression in BCS. The importance of understanding sleep disturbances in cancer populations has been highlighted and recognized as warranting further research. Therefore, the purpose of this systematic review was to determine the prevalence and the risk factors for the development of sleep disturbances in BCS. METHODS: PubMed, Web of Science, and PEDro were systematically screened for studies encompassing data regarding the prevalence or risk factors of sleep disturbances in BCS. If possible, meta-analyses were performed. Subgroup analyses were undertaken based on the methodological quality, study design, type of sleep disturbance, and the use of a measurement tool with strong psychometric properties to investigate significant heterogeneity (I2 > 50%) across studies. RESULTS: A total of 27 studies were found eligible. The pooled estimate for sleep disturbances prevalence is 0.40 (95% confidence interval (CI) = [0.29-0.52], I2 = 100%, p < 0.00001) and ranged from 0.14 (95% CI = [0.04-0.24]) to 0.93 (95% CI = [0.91-0.95]). Subgroup analyses did not reduce the heterogeneity among studies. Meta-analyses were performed for seven risk factors. Significant differences for the odds of developing sleep disturbances were found for hot flashes (pooled OR (ORp) 2.25, 95% CI = [1.64-3.08], I2 = 0%, p = 0.90), race (ORp 2.31, 95% CI = [1.56-3.42], I2 = 0%, p = 0.47), and menopause (ORp 1.84, 95% CI = [1.11-3.06], I2 = 0%, p = 0.70). After withdrawing the studies that did not rely on the use of a measurement tool with strong psychometric properties, pain (ORp 2.31, 95% CI = [1.36-3.92], I2 = 27%, p = 0.25), depressive symptoms (ORp 3.20, 95% CI [2.32-4.42], I2 = 0%, p = 0.63), and fatigue (ORp 2.82, 95% CI = [1.98-4.02], I2 = 0%, p = 0.60) became significant as well, with a substantial decrease of heterogeneity. CONCLUSION: Prevalence for sleep disturbances ranged from 0.14 to 0.93 with the vast majority of the studies investigating insomnia and sleep-wake disturbances. High heterogeneity makes it difficult to draw firm conclusions. Pain, depressive symptoms, hot flashes, fatigue, non-Caucasian race, and menopausal status were significantly associated with increased odds for developing sleep disturbances.

The Brugmann Fatigue Scale: An Analogue to the Epworth Sleepiness Scale to Measure Behavioral Rest Propensity.

Background: While often confused, fatigue (as opposed to sleepiness) mostly requires rest, not sleep, to recover from. Clinical evaluations of fatigue mainly rely on assessments of symptom intensity, however without taking into account the need to engage in behavioral countermeasures. We therefore developed an 8-item 4-point Likert scale (the Brugmann Fatigue Scale; BFS) sharing a similar conceptual background with the Epworth Sleepiness Scale (ESS), assessing mental and physical fatigue and focusing specifically on rest propensity. Methods: Out of 496 consecutive patients addressed to the sleep unit of an academic hospital, we selected a sample of 295 hypnotic-free subjects (122 females). The present study examines (a) the psychometric properties of the BFS and (b) measurement invariance regarding perceived sleep quality, in parallel with common sleepiness and fatigue scales (ESS and Fatigue Severity Scale; FSS). In addition, (c) correlations of the BFS with clinical scales and polysomnographic variables were explored descriptively. Results: Rasch analyses revealed that the BFS possesses sound psychometric characteristics (rating scale functioning, item fit, dimensionality and measurement invariance) allowing for valid, reliable, linear and unidimensional measurement of mental and physical rest propensity, irrespective of perceived sleep quality, age, or gender. In addition, the BFS was significantly correlated to periodic limb movements during sleep and inversely to REM sleep duration. For both mental and physical subscales, scores above 6 are proposed as cutoff values. Conclusion: In analogy to the ESS, the BFS shows to be a unique and precise instrument assessing symptomatic fatigue with respect to rest propensity.

Effect of sleep bruxism duration on perceived sleep quality in middle-aged subjects.

Sleep-related bruxism may directly impact sleep quality. This study aims to evaluate potential relationships between sleep bruxism events and related daytime symptoms. We investigated 22 patients (42.1 ± 11.6 yr of age) with sleep bruxism in comparison with 12 good sleeper control subjects of similar age (41.0 ± 11.5 yr). Sleep bruxism was visually analyzed and categorized according to sleep stage, bruxism type (tonic/phasic) and duration. Clinical instruments comprised the Epworth Sleepiness, the Brugmann Fatigue Scale, and the Hospital Anxiety and Depression Rating Scale. Sleep quality was measured using the Pittsburgh Sleep Quality Index. Controls and patients with sleep bruxism presented similar sleep architecture. However, patients with sleep bruxism displayed significantly decreased sleep efficiency and higher sleep fragmentation. Perceived sleep quality was significantly worse in patients with sleep bruxism than in control subjects. Additionally, patients presented with significantly greater fatigue intensity and more affective symptoms than controls. The cumulative durations of sleep bruxism events (phasic, tonic, and combined) were significantly correlated with deterioration of sleep quality, whereas neither the event index per hour of sleep nor the count of event types (phasic/tonic) were related to sleep quality. Patients with sleep bruxism present with higher levels of daytime fatigue and sleepiness than control subjects who experience good sleep and may also exhibit impairments of sleep quality which are related to the duration of bruxism occurrence rather than to its frequency.

Can positional therapy be simple, effective and well tolerated all together? A prospective study on treatment response and compliance in positional sleep apnea with a positioning pillow.

PURPOSE: Until now, there is no clear consensus on optimal care for mild sleep-related breathing disorders (SRBD) in general or for positional obstructive sleep apnea (POSA) in particular. Most proposed treatment options are either invasive and/or expensive. Positional therapy (PT) may therefore present as a valuable first-line intervention in POSA. METHODS: Twenty-eight patients presenting with POSA were enrolled in a prospective cohort study. The protocol consisted of three nights of polysomnography (PSG) in an academic sleep lab. Inclusion was based on the first PSG. During a consecutive PSG, PT was provided by means of a sleep-positioning pillow (Posiform®). The third PSG was performed after 1 month of PT. Sleepiness, fatigue, and sleep quality were assessed with the Epworth Sleepiness Scale (ESS), the fatigue severity scale (FSS), the Pittsburgh Sleep Quality Index (PSQI), and the Function Outcomes of Sleep Questionnaire (FOSQ) at baseline, and after 1 and at 6 months of PT alongside satisfaction and compliance ratings. RESULTS: Significant immediate treatment effects after one night and sustained after 1 month were observed by significant reductions of sleep in supine position (p < .001), sleep fragmentation (p < .05), apnea-hypopnea (p < .001), respiratory disturbance (p < .001), and oxygen desaturation (p < .001) indices. PSQI (p < .001), ESS (p < .005), and FOSQ (p < .001) also showed significant and persistent improvements. CONCLUSIONS: Combined effects on sleep-related respiration and clinical symptoms were observed after PT initiation as well as after 1 month using the sleep-positioning pillow. Furthermore, reported compliance and overall satisfaction appeared to be highly concordant both at 1 month and 6 months follow-up.

While Isolated Periodic Limb Movement Disorder Significantly Impacts Sleep Depth and Efficiency, Co-Morbid Restless Leg Syndrome Mainly Exacerbates Perceived Sleep Quality.

BACKGROUND: Restless leg syndrome (RLS) and periodic limb movement (PLM) disorder (PLMD) can affect sleep quality and interfere with daytime functioning. Whether the co-morbidity of RLS further worsens daytime symptoms, sleep architecture and quality in patients with PLMs, is not yet fully clarified. METHODS: Sleep (polysomnography) and daytime symptoms of 47 drug-free patients, assigned to isolated PLMD or co-morbid RLS subgroups, were compared to controls in a retrospective cohort-study (n = 501). Associations between perceived sleep quality, fatigue, sleepiness, mood and sleep variables were explored descriptively. RESULTS: Although co-morbid patients showed worsened sleep quality, both patient groups showed similar sleepiness and affective symptoms. While significantly differing from controls, patients presented similarly increased light sleep, decreased slow-wave sleep and lowered sleep efficiency. Altered sleep quality, fatigue and sleepiness were significantly correlated to decreased slow-wave sleep and sleep fragmentation. Affective symptoms, fatigue and perceived sleep quality also correlated to PLM index. CONCLUSIONS: Sleep structure and efficiency were similarly impacted in isolated PLMD and in co-morbid RLS. RLS mainly worsened perceived sleep quality. Given that systematic treatment for isolated PLMD is currently not recommended, such results may question whether no or different-from-RLS treatment strategies are compatible with optimal care.

Dimensions of pure chronic fatigue: psychophysical, cognitive and biological correlates in the chronic fatigue syndrome.

OBJECTIVES: To investigate associated dimensions of fatigue regarding cognitive impairment, psychomotor performances, muscular effort power and circulating cytokine levels and their relations to symptom intensity in a sample of pure chronic fatigue syndrome (CFS) patients without overlapping objective sleepiness or sleep disorders. METHODS: 16 CFS patients were compared to 14 matched controls. We assessed structured symptom-scales, polysomnography, multiple sleep latency tests, attention (Zazzo-Cancellation ZCT, digit-symbol-substitution DSST), psychomotor vigilance and speed (PVT, finger tapping test, FTT), dynamometer handgrip force (tonic and phasic trials) and circulating cytokines (IFN-γ, IL-1b, IL-6, IL-8, IL-10, TNF-α). RESULTS: In addition to fatigue, CFS patients presented with higher affective symptom intensity and worse perceived sleep quality. Polysomnography showed more slow-wave sleep and microarousals in CFS but similar sleep time, efficiency and light-sleep durations than controls. Patients presented with impaired attention (DSST, ZCT), slower reaction times (PVT) but not with lower hit rates (FTT). Notwithstanding lower grip strength during tonic and phasic trials, CFS also presented with higher fatigability during phasic trials. Cytokine levels were increased for IL-1b, IL-8, IL-10 and TNF-α and fatigue intensity was correlated to grip strength and IL-8. CONCLUSIONS: In contrast to sleepiness, chronic fatigue is a more complex phenomenon that cannot be reduced to one single measured dimension (i.e., sleep propensity). Showing its relations to different measurements, our study reflects this multidimensionality, in a psychosomatic disorder such as CFS. To obtain objective information, routine assessments of fatigue should rule out sleepiness, combine aspects of mental and physical fatigue and focus on fatigability.

Chronotype Differences and Symptom Network Dynamics of Post-Pandemic Sleep in Adolescents and Young Adults.

Background: Social restrictions during the COVID-19 pandemic resulted in altered sleep patterns and mental health challenges, particularly among adolescents and young adults. Our objective was to examine the potential difference in insomnia prevalence and sleep patterns in this population between the first COVID-19 lockdown and the post-lockdown period, with a focus on chronotype. Additionally, we explored the network of sleep-related differences between these two periods. Methods: A total of 946 respondents participated in our online questionnaire. We performed mixed ANOVA, Ising network and Directed Acyclic Graph (DAG) analyses. Results: Respondents reported going to bed earlier, waking up earlier, sleeping less, and feeling less mentally tired than during the lockdown. The severity of insomnia symptoms did not change. The lethargic chronotype reported more insomnia symptoms, depressive feelings, and agitation than others. Mental fatigue was the central symptom in the Ising network and served as the parent node in the DAG. Conclusions: Post-lockdown, adolescents and young adults have shifted to earlier sleep and wake times with reduced overall sleep, and they experience fewer depressive feelings and less agitation, though insomnia symptoms remain unchanged. Participants who reported increased irritability or poorer sleep quality during confinement also reported similar or diminished attentional capacities compared to their usual levels.

Sleep, Mental Health, and the Need for Physical and Real-Life Social Contact with (Non-)Family Members during the COVID-19 Pandemic: A Bayesian Network Analysis.

Background/Objectives: The forced social isolation implemented to prevent the spread of the COVID-19 virus was accompanied by a worsening of mental health, an increase in insomnia symptoms, and the emergence of 'skin hunger'-an increased longing for personal touch. This study aimed to enhance our understanding of the interconnection between sleep, mental health, and the need for physical (NPC) and real-life social contact (NRL-SC). Methods: A total of 2827 adults participated in an online survey during the second COVID-19 lockdown. A Bayesian Gaussian copula graphical model (BGCGM) and a Bayesian-directed acyclic graph (DAG) were estimated, and mixed ANOVAs were carried out. Results: NPC with non-family members (t(2091) = 12.55, p < 0.001, d = 0.27) and relational lifestyle satisfaction (t(2089) = 13.62, p < 0.001, d = 0.30) were lower during the second lockdown than before the pandemic. In our BGCGM, there were weak positive edges between the need for PC and RL-SC on one hand and sleep and mental health on the other. Conclusions: During the second lockdown, people craved less physical contact with non-family members and were less satisfied with their relational lifestyle than before the pandemic. Individuals with a greater need for PC and RL-SC reported poorer mental health (i.e., worry, depression, and mental fatigue).

Promoting mental health in esports.

There is growing recognition of the demands and health challenges experienced by esports athletes. The purpose of this perspective paper is to draw specific attention to the mental health of competitive gamers and spur on both future research and applied initiatives focussing on this important but under-addressed topic. We will briefly discuss the prevalence of mental health concerns, domain-specific stressors, and the need for comprehensive mental health support systems tailored to the esports context. It is our hope that, with this perspective paper, we can help set a new research agenda addressing mental health in esports.

Integration of Cognitive Behavioral Therapy for Insomnia in Best-Practice Care for Patients With Knee Osteoarthritis and Insomnia: A Randomized Controlled Trial Protocol.

OBJECTIVE: Knee osteoarthritis (KOA) is a common musculoskeletal problem worldwide and its key symptom is pain. Guidelines recommend incorporating comorbidity-specific therapies into patient-centered care. Patients diagnosed with KOA frequently have insomnia, which is associated with higher-pain severity. For this reason, this study protocol outlines the methodology of a randomized controlled trial (RCT) investigating the effectiveness of cognitive behavioral therapy for insomnia (CBTi) combined with best-practice KOA care (BPC) compared to best-practice KOA care and lifestyle education. METHODS: A 2-arm RCT in patients with KOA and insomnia is conducted, in which a total of 128 patients are randomly allocated to an intervention or control group. The experimental intervention consists of 12 sessions of physical therapist-led BPC with an additional 6 sessions of CBTi. The control intervention also receives BPC, which is supplemented with 6 general lifestyle information sessions. The primary outcome is the between-group difference in change in pain severity at 6 months after intervention. Secondary outcomes are pain-related outcomes, sleep-related outcomes, symptoms of anxiety and depression, level of physical activity and function, perceived global improvement, biomarkers of inflammation, and health-related quality of life. Assessments are conducted at baseline, immediately after intervention, and 3, 6, and 12 months after intervention. Furthermore, a cost-utility analysis for the proposed intervention will be performed alongside the RCT. IMPACT: This is the first RCT investigating the clinical and cost-effectiveness of a physical therapist-led intervention integrating CBTi into BPC in patients with KOA and insomnia. The results of this trial will add to the growing body of evidence on the effectiveness of individualized and comorbidity-specific KOA care, which can inform clinical decision-making and assist policymakers and other relevant stakeholders in optimizing the care pathway for patients with KOA.

The bidirectional relationship between sleep problems and chronic musculoskeletal pain: a systematic review with meta-analysis.

ABSTRACT: Chronic musculoskeletal pain and sleep problems/disorders exhibit a recognized bidirectional relationship; yet, systematic investigations of this claim, particularly in a prospective context, are lacking. This systematic review with meta-analysis aimed to synthesize the literature on the prospective associations between sleep problems/disorders and chronic musculoskeletal pain. A comprehensive search across 6 databases identified prospective longitudinal cohort studies in adults examining the relationship between sleep problems/disorders and chronic musculoskeletal pain. Random-effects meta-analyses, using the Hartung-Knapp adjustment for 95% confidence intervals (CIs), were conducted, and all results were presented as odds ratios (ORs). Certainty of evidence was evaluated using the Grading of Recommendations, Assessment, Development, and Evaluations approach. Including 16 articles from 11 study populations (116,746 participants), meta-analyses indicated that sleep problems at baseline may heighten the risk of chronic musculoskeletal pain in both short term (OR 1.64, 95% CI 1.01-2.65) and long term (OR 1.39, 95% CI 1.21-1.59). The evidence for different sleep problem categories was very uncertain. Chronic musculoskeletal pain at baseline may increase the risk of short-term sleep problems (OR 1.56, 95% CI 1.02-2.38), but long-term evidence was very uncertain. The impact of only local or only widespread pain on short-term sleep problems was very uncertain, whereas widespread pain may elevate the risk of long-term sleep problems (OR 2.0, 95% CI 1.81-2.21). In conclusion, this systematic review with meta-analysis suggests that sleep problems are associated with an increased risk of chronic musculoskeletal pain, but the bidirectional nature of this relationship requires further investigation.

The Role of Anxiety and Depression in Shaping the Sleep-Pain Connection in Patients with Nonspecific Chronic Spinal Pain and Comorbid Insomnia: A Cross-Sectional Analysis.

(1) Background: This exploratory study aims to explore the relationship between nonspecific chronic spinal pain (nCSP) and insomnia symptoms, by examining the interconnections, strengths, and directional dependence of the symptoms. In addition, we aim to identify the key symptoms of the nCSP-insomnia relationship and shed light on the bidirectional nature of this relationship. (2) Methods: This study is a secondary analysis of the baseline data (cross-sectional) from a randomized controlled trial, which examined the added value of Cognitive Behavioral Therapy for Insomnia (CBT-I) combined with cognition-targeted exercise therapy, conducted in collaboration with the Universiteit Gent and Vrije Universiteit Brussel (Belgium). One hundred and twenty-three nCSP patients with comorbid insomnia were recruited through the participating hospitals, advertisements, announcements in local newspapers, pharmacies, publications from support groups, and primary care. To explore the interconnections and directionality between symptoms and the strengths of the relationships, we estimated a regularized Gaussian graphical model and a directed acyclic graph. (3) Results: We found only one direct, but weak, link between sleep and pain, namely, between average pain and difficulties maintaining sleep. (4) Conclusions: Despite the lack of strong direct links between sleep and pain, pain and sleep seem to be indirectly linked via anxiety and depression symptoms, acting as presumable mediators in the network of nCSP and comorbid insomnia. Furthermore, feeling slowed down and fatigue emerged as terminal nodes, implying their role as consequences of the network.

Cognitive Behavioral Therapy for Insomnia in Pain Management for Nonspecific Chronic Spinal Pain: A Randomized Clinical Trial.

Importance: Insomnia is highly prevalent in patients with nonspecific chronic spinal pain (nCSP). Given the close interaction between insomnia and pain, targeting sleep problems during therapy could improve treatment outcomes. Objective: To evaluate the effectiveness of cognitive behavioral therapy for insomnia (CBTi) integrated in best-evidence pain management (BEPM) vs BEPM only in patients with nCSP and insomnia. Design, Setting, and Participants: A multicenter randomized clinical trial with 1-year follow-up was conducted between April 10, 2018, and April 30, 2022. Data and statistical analysis were performed between May 1, 2022, and April 24, 2023. Patients with nCSP and insomnia were evaluated using self-report and at-home polysomnography, to exclude underlying sleep pathologic factors. Participants were treated at the University Hospital Brussels or University Hospital Ghent, Belgium. Intention-to-treat analysis was performed. Interventions: Participants were randomized to either CBTi-BEPM or BEPM only. Both groups received 18 treatment sessions over 14 weeks. The CBTi-BEPM treatment included 6 CBTi sessions and 12 BEPM sessions. The BEPM treatment included pain neuroscience education (3 sessions) and exercise therapy (9 sessions in the CBTi-BEPM group, 15 sessions in the BEPM-only group). Main Outcomes and Measures: The primary outcome was change in mean pain intensity (assessed with Brief Pain Inventory [BPI]) at 12 months after the intervention. Exploratory secondary outcomes included several pain- and sleep-related outcomes. Blinded outcome assessment took place at baseline, posttreatment, and at 3-, 6-, and 12-month follow-up. Results: A total of 123 patients (mean [SD] age, 40.2 [11.18] years; 84 women [68.3%]) were included in the trial. In 99 participants (80.5%) with 12-month BPI data, the mean pain intensity at 12 months decreased by 1.976 points (reduction of 40%) in the CBTi-BEPM group and 1.006 points (reduction of 24%) points in the BEPM-only group. At 12 months, there was no significant difference in pain intensity change between groups (mean group difference, 0.970 points; 95% CI, -0.051 to 1.992; Cohen d, 2.665). Treatment with CBTi-BEPM resulted in a response for BPI average pain with a number needed to treat (NNT) of 4 observed during 12 months. On a preliminary basis, CBTi-BEPM was, consistently over time and analyses, more effective than BEPM only for improving insomnia severity (Cohen d, 4.319-8.961; NNT for response ranging from 2 to 4, and NNT for remission ranging from 5 to 12), sleep quality (Cohen d, 3.654-6.066), beliefs about sleep (Cohen d, 5.324-6.657), depressive symptoms (Cohen d, 2.935-3.361), and physical fatigue (Cohen d, 2.818-3.770). No serious adverse effects were reported. Conclusions and Relevance: In this randomized clinical trial, adding CBTi to BEPM did not further improve pain intensity reduction for patients with nCSP and comorbid insomnia more than BEPM alone. Yet, as CBTi-BEPM led to significant and clinically important changes in insomnia severity and sleep quality, CBTi integrated in BEPM should be considered in the treatment of patients with nCSP and comorbid insomnia. Further research can investigate the patient characteristics that moderate the response to CBTi-BEPM in terms of pain-related outcomes, as understanding of these moderators may be of utmost clinical importance. Trial Registration: Clinical Trials.gov Identifier: NCT03482856.

Intensity and Network Structure of Insomnia Symptoms and the Role of Mental Health During the First Two Waves of the COVID-19 Pandemic.

Purpose: Insomnia, being a mental disorder, is best conceived as a network of symptoms. With the important increase in insomnia prevalence during the COVID-19 pandemic, our aim was to investigate how the structure of insomnia symptoms in the general population has changed due to the pandemic. We also looked at the directional dependencies of nightmares and of covid- and lockdown-related stress/anxiety and depression in insomnia. Patients and Methods: 5986 persons replied to our online questionnaire for the first wave and 2843 persons to our second wave questionnaire. Both questionnaires included the Insomnia Severity Index (ISI). Regularized Gaussian Graphical Models (GGM) and Bayesian Directed Acyclic Graphs (DAG) were estimated. Results: The pre- and peri-lockdown networks were equally strongly connected (first wave: S = 0.13, p = 0.39; second wave: S = 0.03, p = 0.67), but differed for the first lockdown regarding only six edges (M = 0.13, p < 0.001) and for the second lockdown only five edges (M = 0.16, p < 0.001). These symptoms all worsened during the lockdowns in comparison to before the pandemic (p < 0.001). The diurnal items of the ISI had the highest predictability and centrality values in the GGMs. Lockdown-related stress/anxiety influenced indirectly nightmares through covid-related stress/anxiety, lockdown-related depressive affect and mental fatigue. These reported feelings of stress/anxiety and depression showed an indirect impact on insomnia symptoms through mental and physical fatigue. Conclusion: Though the lockdown slightly intensified insomnia symptoms, it did not alter their network structure. Despite their differences, both GGMs and DAGs agree that the diurnal symptoms of the ISI, play an essential role in the network structure. Both methods confirm the need for emphasizing the cognitive/affective component in the treatment of insomnia (ie cognitive behavioral therapy).

Relationship, differences, and agreement between objective and subjective sleep measures in chronic spinal pain patients with comorbid insomnia: a cross-sectional study.

ABSTRACT: Sleep disturbances are one of the most frequent reported problems in people with nonspecific chronic spinal pain (nCSP) and presents an additional treatment challenge. Interventions targeting sleep problems are mainly based on subjective sleep complaints and do not take objective sleep into consideration. The aim of this cross-sectional study was to evaluate the relationship and conformity between self-reported and objectively measured sleep parameters (ie, questionnaire vs polysomnography and actigraphy). The baseline data of 123 people with nCSP and comorbid insomnia who are participating in a randomized controlled trial were analyzed. Pearson correlations were used to investigate the relationship between objective and subjective sleep parameters. Differences between objective and subjective sleep parameters were analyzed using t tests. Bland-Altman analyses were performed to quantify and visualize agreement between the different measurement methods. Except for the significant moderate correlation between perceived time in bed (TIB) and actigraphic TIB ( r = 0.667, P < 0.001), all other associations between subjective and objective measures were rather weak ( r < 0.400). Participants underestimated their total sleep time (TST) (mean difference [MD] = -52.37 [-67.94, -36.81], P < 0.001) and overestimated sleep onset latency (SOL) (MD = 13.76 [8.33, 19.20], P < 0.001) in general. The results of this study suggest a discrepancy (differences and lack of agreement) between subjective and objective sleep parameters in people with nCSP and comorbid insomnia. No or weak associations were found between self-reported sleep and objectively measured sleep. Findings suggest that people with nCSP and comorbid insomnia tend to underestimate TST and overestimate SOL. Future studies are necessary to confirm our results.

The interplay between symptoms of insomnia and pain in people with osteoarthritis: A narrative review of the current evidence.

Osteoarthritis (OA) is a leading cause of disability worldwide and clinical pain is the major symptom of OA. This clinical OA-related pain is firmly associated with symptoms of insomnia, which are reported in up to 81% of people with OA. Since understanding the association between both symptoms is critical for their appropriate management, this narrative review synthesizes the existing evidence in people with OA on i) the mechanisms underlying the association between insomnia symptoms and clinical OA-related pain, and ii) the effectiveness of conservative non-pharmacological treatments on insomnia symptoms and clinical OA-related pain. The evidence available identifies depressive symptoms, pain catastrophizing and pain self-efficacy as mechanisms partially explaining the cross-sectional association between insomnia symptoms and pain in people with OA. Furthermore, in comparison to treatments without a specific insomnia intervention, the ones including an insomnia intervention appear more effective for improving insomnia symptoms, but not for reducing clinical OA-related pain. However, at a within-person level, treatment-related positive effects on insomnia symptoms are associated with a long-term pain reduction. Future longitudinal prospective studies offering fundamental insights into neurobiological and psychosocial mechanisms explaining the association between insomnia symptoms and clinical OA-related pain will enable the development of effective treatments targeting both symptoms.

Do Patients with Chronic Spinal Pain and Comorbid Insomnia Have More Features of Central Sensitization? A Case-Control Study.

BACKGROUND: Chronic spinal pain (CSP) is a major public health problem worldwide, frequently related to sleep problems. Central sensitization (CS) may worsen the clinical picture of CSP patients with insomnia. The aim of this study was to compare self-reported and objectively measured clinical outcomes between insomniac CSP patients with comorbid insomnia with and without symptoms of CS. METHODS: A case-control study on baseline self-reported sleep, functioning, and psychological distress through online questionnaires. Objective sleep and physical activity parameters and pressure pain thresholds (PPTs) were assessed through polysomnography, actigraphy, and digital algometry, respectively. Independent sample t-test and Mann-Whitney U tests were used to examine possible differences in the outcome measures between the groups. RESULTS: Data from 123 participants were included and revealed no statistically significant group for objective sleep and physical activity parameters. The CS group, however, presented with worse self-reported sleep (quality sleep, insomnia severity, and dysfunctional beliefs about sleep), increased mental and physical fatigue, and higher psychological distress (anxiety and depressive symptoms), and reported lower PPTs. CONCLUSIONS: symptoms of CS may influence perceived sleep and affect functional health and well-being perception but do not seem to affect objective sleep and physical activity.

Prevalence of Insomnia and Sleep Habits during the First and Second Wave of COVID-19 in Belgium.

Belgium has one of the highest numbers of COVID-19 cases per 1 million inhabitants. The pandemic has led to significant societal changes with repercussions on sleep and on mental health. We aimed to investigate the effect of the first and the second wave of COVID-19 on the sleep of the Belgian populationWe launched two online questionnaires, one during the first lockdown (7240 respondents) and one during the second (3240 respondents), to test differences in self-reported clinical insomnia (as measured by the Insomnia Severity Index) and sleep habits during the two lockdowns in comparison with the pre-COVID period. The number of persons with clinical insomnia rose during the first lockdown (19.22%) and further during the second (28.91%) in comparison with pre-lockdown (7.04-7.66%). Bed and rise times were delayed and there was an increased time in bed and sleep onset latency. There was further a decrease in total sleep time and in sleep efficiency during both confinements. The prevalence of clinical insomnia quadrupled during the second wave in comparison with the pre-lockdown situation. Sleep habits were most altered in the younger population, indicating a greater risk for this group to develop a sleep-wake rhythm disorder.

Impact of Sleep Fragmentation on Cognition and Fatigue.

Sleep continuity and efficacy are essential for optimal cognitive functions. How sleep fragmentation (SF) impairs cognitive functioning, and especially cognitive fatigue (CF), remains elusive. We investigated the impact of induced SF on CF through the TloadDback task, measuring interindividual variability in working memory capacity. Sixteen participants underwent an adaptation polysomnography night and three consecutive nights, once in a SF condition induced by non-awakening auditory stimulations, once under restorative sleep (RS) condition, counterbalanced within-subject. In both conditions, participants were administered memory, vigilance, inhibition and verbal fluency testing, and for CF the TloadDback, as well as sleep questionnaires and fatigue and sleepiness visual analog scales were administered. Subjective fatigue increased and sleep architecture was altered after SF (reduced sleep efficiency, percentage of N3 and REM, number of NREM and REM phases) despite similar total sleep time. At the behavioral level, only inhibition deteriorated after SF, and CF similarly evolved in RS and SF conditions. In line with prior research, we show that SF disrupts sleep architecture and exerts a deleterious impact on subjective fatigue and inhibition. However, young healthy participants appear able to compensate for CF induced by three consecutive SF nights. Further studies should investigate SF effects in extended and/or pathological disruption settings.