Brain mechanisms of insomnia: new perspectives on causes and consequences.

While insomnia is the second most common mental disorder, progress in our understanding of underlying neurobiological mechanisms has been limited. The present review addresses the definition and prevalence of insomnia and explores its subjective and objective characteristics across the 24-hour day. Subsequently, the review extensively addresses how the vulnerability to develop insomnia is affected by genetic variants, early life stress, major life events, and brain structure and function. Further supported by the clear mental health risks conveyed by insomnia, the integrated findings suggest that the vulnerability to develop insomnia could rather be found in brain circuits regulating emotion and arousal than in circuits involved in circadian and homeostatic sleep regulation. Finally, a testable model is presented. The model proposes that in people with a vulnerability to develop insomnia, the locus coeruleus is more sensitive to-or receives more input from-the salience network and related circuits, even during rapid eye movement sleep, when it should normally be sound asleep. This vulnerability may ignite a downward spiral of insufficient overnight adaptation to distress, resulting in accumulating hyperarousal, which, in turn, impedes restful sleep and moreover increases the risk of other mental health adversity. Sensitized brain circuits are likely to be subjectively experienced as "sleeping with one eye open". The proposed model opens up the possibility for novel intervention studies and animal studies, thus accelerating the ignition of a neuroscience of insomnia, which is direly needed for better treatment.

Orexin Receptor Antagonism: Normalizing Sleep Architecture in Old Age and Disease.

Sleep is essential for human well-being, yet the quality and quantity of sleep reduce as age advances. Older persons (>65 years old) are more at risk of disorders accompanied and/or exacerbated by poor sleep. Furthermore, evidence supports a bidirectional relationship between disrupted sleep and Alzheimer's disease (AD) or related dementias. Orexin/hypocretin neuropeptides stabilize wakefulness, and several orexin receptor antagonists (ORAs) are approved for the treatment of insomnia in adults. Dysregulation of the orexin system occurs in aging and AD, positioning ORAs as advantageous for these populations. Indeed, several clinical studies indicate that ORAs are efficacious hypnotics in older persons and dementia patients and, as in adults, are generally well tolerated. ORAs are likely to be more effective when administered early in sleep/wake dysregulation to reestablish good sleep/wake-related behaviors and reduce the accumulation of dementia-associated proteinopathic substrates. Improving sleep in aging and dementia represents a tremendous opportunity to benefit patients, caregivers, and health systems.

Temporal relations between peripheral and central arousals in good and poor sleepers.

Good sleepers and patients with insomnia symptoms (poor sleepers) were tracked with two measures of arousal; conventional polysomnography (PSG) for electroencephalogram (EEG) assessed cortical arousals, and a peripheral arterial tonometry device was used for the detection of peripheral nervous system (PNS) arousals associated with vasoconstrictions. The relationship between central (cortical) and peripheral (autonomic) arousals was examined by evaluating their close temporal dynamics. Cortical arousals almost invariably were preceded and followed by peripheral activations, while large peripheral autonomic arousals were followed by cortical arousals only half of the time. The temporal contiguity of these two types of arousals was altered in poor sleepers, and poor sleepers displayed a higher number of cortical and peripheral arousals compared with good sleepers. Given the difference in the number of peripheral autonomic arousals between good and poor sleepers, an evaluation of such arousals could become a means of physiologically distinguishing poor sleepers.

The 103,200-arm acceleration dataset in the UK Biobank revealed a landscape of human sleep phenotypes.

SignificanceHuman sleep phenotypes are diversified by genetic and environmental factors, and a quantitative classification of sleep phenotypes would lead to the advancement of biomedical mechanisms underlying human sleep diversity. To achieve that, a pipeline of data analysis, including a state-of-the-art sleep/wake classification algorithm, the uniform manifold approximation and projection (UMAP) dimension reduction method, and the density-based spatial clustering of applications with noise (DBSCAN) clustering method, was applied to the 100,000-arm acceleration dataset. This revealed 16 clusters, including seven different insomnia-like phenotypes. This kind of quantitative pipeline of sleep analysis is expected to promote data-based diagnosis of sleep disorders and psychiatric disorders that tend to be complicated by sleep disorders.

Decreased Delta/Beta ratio index as the sleep state-independent electrophysiological signature of sleep state misperception in Insomnia disorder: A focus on the sleep onset and the whole night.

PURPOSE: Sleep State Misperception (SSM) is described as the tendency of Insomnia Disorder (ID) patients to overestimate Sleep Latency (SL) and underestimate Total Sleep Time (TST). Literature exploring topographical components in ID with SSM is scarce and does not allow us to fully understand the potential mechanisms underlying this phenomenon. This study aims to evaluate the existence of sleep EEG topography alterations in ID patients associated with SSM compared to Healthy Controls (HC), focusing on two distinct periods: the Sleep Onset (SO) and the whole night. METHODS: Twenty ID patients (mean age: 43.5 ± 12.7; 7 M/13F) and 18 HCs (mean age: 41.6 ± 11.9; 8 M/10F) underwent a night of Polysomnography (PSG) and completed sleep diaries the following morning upon awakening. Two SSM indices, referring to the misperception of SL (SLm) and TST (TSTm), were calculated by comparing objective and subjective sleep indices extracted by PSG and sleep diary. According to these indices, the entire sample was split into 4 sub-groups: ID +SLm vs HC -SLm; ID +TSTm vs HC -TSTm. RESULTS: Considering the SO, the two-way mixed-design ANOVA showed a significant main effect of Groups pointing to a decreased delta/beta ratio in the whole scalp topography. Moreover, we found a significant interaction effect for the sigma and beta bands. Post Hoc tests showed higher sigma and beta power in anterior and temporo-parietal sites during the SO period in IDs +SLm compared to HC -SLm. Considering the whole night, the unpaired t-test revealed in IDs +TSTm significantly lower delta power during NREM, and lower delta/beta ratio index during NREM and REM sleep compared to HCs -TSTm. Finally, we found diffuse significant negative correlations between SSM indices and the delta/beta ratio during SO, NREM, and REM sleep. CONCLUSION: The main finding of the present study suggests that higher SL overestimation and TST underestimation are both phenomena related to diffuse cortical hyperarousal interpreted as a sleep state-independent electrophysiological correlate of the SSM, both during the SO and the whole night.

Analysis of the correlation between immune cell characteristics and insomnia: a Mendelian randomization study.

Insomnia, recognized as a prevalent sleep disorder, has garnered extensive attention within the realm of public health. Recent studies indicate a close interaction between the immune system and sleep; however, the specific mechanism remains not yet fully understood. Based on the publicly available Genome-Wide Association Study (GWAS) data, we used two-sample Mendelian randomization (MR) analyses to investigate the associations between 731 immune cell traits and insomnia risk. Five MR analysis methods and a comprehensive sensitivity analysis were used to evaluate the reliability of the results. In this study, we identified that 14 immune characteristics among four immune profiles [median fluorescence intensity (MFI), relative cell count (RC), absolute cell count (AC), and morphological parameters (MP)] demonstrated a significant causal association with insomnia. Specifically, eight immune cell characteristics were associated with an increased risk of insomnia, including CD11c+ monocyte% (P < 0.001), CD11c+ HLA DR++ monocyte% (P = 0.004), CD86+ plasmoid dendritic cell (DC) AC (P < 0.001), CD33br HLA DR+ CD14dim AC (P < 0.001), CD8dim AC (P = 0.002), CCR2 on CD14+ CD16- monocyte (P < 0.001), CD39 on monocyte (P < 0.001), and SSC-A on myeloid DC (P < 0.001). Six immune cell characteristics demonstrated protective effects against insomnia, including PB/PC %B cell (P < 0.001), CM CD4+% CD4+ (P < 0.001), T-cell AC (P < 0.001), BAFF-R on IgD- CD38br (P < 0.001), CD16-CD56 on HLA DR+ NK cells (P < 0.001), and CD14 on CD33br HLA DR+ CD14dim (P < 0.001). Our study established the correlation between immune cell characteristics and insomnia, offering a novel theoretical foundation for the concept of sleep-immune cross talk.NEW & NOTEWORTHY This study investigated the association between 731 immune cell characteristics and insomnia using Mendelian randomization, revealing that 14 immune cell characteristics across four groups of immune traits (MFI, RC, AC, and MP) have a significant and causal association with insomnia risk. Our results contribute to the understanding of the sleep-immune cross talk doctrine and offer a new theoretical basis for immune modulation in treating insomnia.

Fecal Microbiota Transplantation for Sleep Disturbance in Post-acute COVID-19 Syndrome.

BACKGROUND & AIMS: Post-acute COVID-19 syndrome (PACS) is associated with sleep disturbance, but treatment options are limited. The etiology of PACS may be secondary to alterations in the gut microbiome. Here, we report the efficacy of fecal microbiota transplantation (FMT) in alleviating post-COVID insomnia symptoms in a nonrandomized, open-label prospective interventional study. METHODS: Between September 22, 2022, and May 22, 2023, we recruited 60 PACS patients with insomnia defined as Insomnia Severity Index (ISI) ≥8 and assigned them to the FMT group (FMT at weeks 0, 2, 4, and 8; n = 30) or the control group (n = 30). The primary outcome was clinical remission defined by an ISI of <8 at 12 weeks. Secondary outcomes included changes in the Pittsburgh Sleep Quality Index, Generalized Anxiety Disorder-7 scale, Epworth Sleepiness Scale, Multidimensional Fatigue Inventory, blood cortisol and melatonin, and gut microbiome analysis on metagenomic sequencing. RESULTS: At week 12, more patients in the FMT than the control group had insomnia remission (37.9% vs 10.0%; P = .018). The FMT group showed a decrease in ISI score (P < .0001), Pittsburgh Sleep Quality Index (P < .0001), Generalized Anxiety Disorder-7 scale (P = .0019), Epworth Sleepiness Scale (P = .0057), and blood cortisol concentration (P = .035) from baseline to week 12, but there was no significant change in the control group. There was enrichment of bacteria such as Gemmiger formicilis and depletion of microbial pathways producing menaquinol derivatives after FMT. The gut microbiome profile resembled that of the donor in FMT responders but not in nonresponders at week 12. There was no serious adverse event. CONCLUSIONS: This pilot study showed that FMT could be effective and safe in alleviating post-COVID insomnia, and further clinical trials are warranted. CLINICALTRIALS: gov, Number: NCT05556733.

Association between modifiable lifestyle factors and telomere length: a univariable and multivariable Mendelian randomization study.

BACKGROUND: Telomere length has long been recognized as a valuable biomarker of aging and is inversely correlated with chronological age. Various lifestyle factors have been implicated in telomere shortening or preservation; however, the association between lifestyle factors and telomere length remains controversial. To address this issue, we conducted a Mendelian randomization (MR) analysis to investigate the potential causal associations between multiple lifestyle factors and telomere length. METHODS: Independent genetic variants strongly associated with lifestyle factors (tobacco smoking, sleep duration, insomnia, and physical activity) were selected as instrumental variables from corresponding genome-wide association studies (GWASs). Summary-level data for telomere length was obtained from a GWAS comprising 472,174 European ancestries. Univariable and multivariable MR analyses were performed to assess the relationships. RESULTS: The genetic liability to lifetime smoking was robustly associated with shorter telomere length (odd ratio [OR]: 0.882; 95% confidence interval [CI]: 0.847-0.918). Genetically predicted insomnia was also linked to shorter telomere length (OR: 0.972; 95% CI: 0.959-0.985), while no significant association was observed between sleep duration and telomere length. Furthermore, a suggestive association was found between moderate-to-vigorous physical activity and longer telomere length (OR: 1.680; 95% CI: 1.115-2.531). In multivariable MR analyses, adjusting for potential mediators such as body mass index, type 2 diabetes, alcohol consumption, and alcohol use disorder, the associations of lifetime smoking and insomnia with telomere length remained robust. CONCLUSION: Our findings suggest that smoking and insomnia may contribute to telomere shortening, while physical activity may play a role in telomere length maintenance. These findings underscore the importance of managing positive risk factors and adopting a healthy lifestyle to promote telomere health.

Clinically recognized sleep disorders in people living with HIV.

OBJECTIVE: Despite recognition that people with HIV (PWH) are more vulnerable to sleep issues, there is limited understanding of clinically recognized sleep disorders in this population. Our objective was to evaluate the full spectrum of sleep disorder types diagnosed among PWH in care. METHODS: We conducted a retrospective cohort study of PWH, and a comparator group of people without HIV (PWoH), in a large healthcare system. The incidence of clinically diagnosed sleep disorders was calculated using Poisson regression for three outcomes: any type of sleep disorder, insomnia, and sleep apnea. Incidence was compared between PWH and PWoH by computing the adjusted incidence rate ratio (aIRR), accounting for sleep disorder risk factors. Comparisons to PWoH were made for all PWH combined, then with PWH stratified by HIV management status (well-managed HIV defined as being on antiretroviral therapy, HIV RNA <200 copies/mL, and CD4 count ≥500 cells/µL). RESULTS: The study included 9076 PWH and 205 178 PWoH (mean age 46 years, 90% men). Compared with PWoH, sleep disorder incidence was greater among PWH overall [aIRR = 1.19, 95% confidence interval (CI): 1.12-1.26], particularly for insomnia (aIRR = 1.56, 95% CI: 1.45-1.67). Sleep apnea incidence was lower among PWH (aIRR = 0.90, 95% CI: 0.84-0.97). In HIV management subgroups, PWH without well-managed HIV had lower sleep apnea incidence (vs. PWoH: aIRR = 0.79, 95% CI: 0.70-0.89) but PWH with well-managed HIV did not (vs. PWoH: aIRR = 0.97, 95% CI: 0.89-1.06). CONCLUSIONS: PWH have high sleep disorder incidence, and insomnia is the most common clinical diagnosis. Lower sleep apnea incidence among PWH may reflect underdiagnosis in those with sub-optimally treated HIV and will be important to investigate further.

The synergistic effect of insomnia and depression on risk of herpes zoster.

Sleep problems was associated with increased risk for herpes zoster (HZ). This study examined subjects with insomnia or a combination of insomnia and depression and their risk of HZ. This retrospective cohort study included a total of 47,256 participants, with a control comprising 31,504 age- and sex-matched patients. Clinical data from 2000 to 2013 in the Taiwan National Health Insurance Research Database were used for analysis. Insomnia, depression, and HZ were defined according to the International Classification of Diseases, Ninth Revision, Clinical Modification. Subjects with insomnia had a significantly higher incidence of HZ (2.77 per 1000 person-years) than the controls (1.81 per 1000 person-years) as well as a higher risk of developing HZ (adjusted hazard ratio (AHR) = 1.62, 95% confidence interval (CI) = 1.35-1.93). Results shown subjects with insomnia durations of < 4 years, 4-6 years, and > 6 years had a significantly higher risk of HZ compared with the controls (AHR: 6.69, 95% CI 4.44-9.39; AHR: 4.42, 95% CI 3.07-6.36; AHR:1.38, 95% CI 1.14-1.87, respectively). We found a significantly higher risk of HZ in subjects with both insomnia and depression (AHR = 4.95; 95% CI = 3.99-7.02) than in those without related conditions. Patients with insomnia, and even more so those with comorbid depression, had a higher risk of developing HZ. This indicates a joint effect of insomnia and depression on HZ.

Who benefits from indirect prevention and treatment of depression using an online intervention for insomnia? Results from an individual-participant data meta-analysis.

BACKGROUND: Major depressive disorder (MDD) is highly prevalent and burdensome for individuals and society. While there are psychological interventions able to prevent and treat MDD, uptake remains low. To overcome structural and attitudinal barriers, an indirect approach of using online insomnia interventions seems promising because insomnia is less stigmatized, predicts MDD onset, is often comorbid and can outlast MDD treatment. This individual-participant-data meta-analysis evaluated the potential of the online insomnia intervention GET.ON Recovery as an indirect treatment to reduce depressive symptom severity (DSS) and potential MDD onset across a range of participant characteristics. METHODS: Efficacy on depressive symptom outcomes was evaluated using multilevel regression models controlling for baseline severity. To identify potential effect moderators, clinical, sociodemographic, and work-related variables were investigated using univariable moderation and random-forest methodology before developing a multivariable decision tree. RESULTS: IPD were obtained from four of seven eligible studies (N = 561); concentrating on workers with high work-stress. DSS was significantly lower in the intervention group both at post-assessment (d = -0.71 [95% CI-0.92 to -0.51]) and at follow-up (d = -0.84 [95% CI -1.11 to -0.57]). In the subsample (n = 121) without potential MDD at baseline, there were no significant group differences in onset of potential MDD. Moderation analyses revealed that effects on DSS differed significantly across baseline severity groups with effect sizes between d = -0.48 and -0.87 (post) and d = - 0.66 to -0.99 (follow-up), while no other sociodemographic, clinical, or work-related characteristics were significant moderators. CONCLUSIONS: An online insomnia intervention is a promising approach to effectively reduce DSS in a preventive and treatment setting.

The association between changes in clinical pain severity and IL-6 reactivity among patients undergoing total knee Arthroplasty: The moderating role of change in insomnia.

Knee osteoarthritis (KOA) is linked to an enhanced release of interleukin-6 (IL-6). Increased levels of IL-6 are associated with greater pain and insomnia. While total knee arthroplasty (TKA) typically results in the reduction of pain, for a subgroup of patients, pain does not improve. Understanding patients' propensity to upregulate IL-6 may provide insight into variation in the clinical success of TKA for improving pain, and insomnia may play an important modulatory role. We investigated the association between pre- and post-surgical changes in clinical pain and IL-6 reactivity, and whether change in insomnia moderated this association. Patients (n = 39) with KOA came in-person before and 3-months after TKA. At both visits, patients completed validated measures of clinical pain and insomnia, as well as underwent quantitative sensory testing (QST). Blood samples were collected to analyze IL-expression both before and after QST procedures to assess changes in IL-6 in response to QST (IL-6 reactivity). Patients were categorized into two groups based on change in clinical pain from pre- to post-surgery: 1) pain decreased > 2 points (pain improved) and 2) pain did not decrease > 2 points (pain did not improve). Based on this definition, 49 % of patients had improved pain at 3-months. Among patients with improved pain, IL-6 reactivity significantly decreased from pre- to post-surgery, whereas there was no significant change in IL-6 reactivity among those whose pain did not improve. There was also a significant interaction between pain status and change in insomnia, such that among patients whose insomnia decreased over time, improved pain was significantly associated with a reduction in IL-6 reactivity. However, among patients whose insomnia increased over time, pain status and change in IL-6 reactivity were not significantly associated. Our findings suggest that the resolution of clinical pain after TKA may be associated with discernible alterations in pro-inflammatory responses that can be measured under controlled laboratory conditions, and this association may be moderated by perioperative changes in insomnia. Randomized controlled trials which carefully characterize the phenotypic features of patients are needed to understand how and for whom behavioral interventions may be beneficial in modulating inflammation, pain, and insomnia.

Tai Chi compared with cognitive behavioral therapy and the reversal of systemic, cellular and genomic markers of inflammation in breast cancer survivors with insomnia: A randomized clinical trial.

BACKGROUND: Insomnia contributes to inflammation in breast cancer survivors. This study evaluates whether insomnia treatment reverses inflammation in breast cancer survivors with insomnia. METHODS: Participants (n = 90) were randomized to 3 months of Tai Chi (n = 45) or cognitive behavioral therapy for insomnia (CBT-I)(n = 45), and followed for one year post-intervention to 15 month endpoint. Our previous report found that Tai Chi as compared to CBT-I resulted in similar rates of insomnia response and remission over 15 months. Here, we analyze changes in plasma C-reactive protein and pro- and anti-inflammatory cytokines, Toll-like receptor (TLR)-4 stimulated monocyte production of interleukin (IL)-6 and tumor necrosis factor-α (TNF), and cellular pro-inflammatory and anti-viral gene expression (Conserved Transcriptional Response to Adversity RNA profile; CTRA) over 15 months. RESULTS: Insomnia treatment resulted in decreases in the TLR-4 stimulated monocyte production of IL-6, TNF, and their co-expression, as well as decreases in the CTRA profile, decreases inflammatory gene transcripts, and increases in anti-viral gene transcripts over 15 months (all P's < 0.01). In addition, as compared to CBT-I, Tai Chi resulted in greater decreases in plasma IL-6 (P < 0.05), and greater decreases in TLR-4 activated monocyte production of IL-6 and co-expression of IL-6 and TNF at 15 month endpoint. CBT-I resulted in greater increases in anti-viral gene transcripts. CONCLUSIONS: Administration of either CBT-I or Tai Chi effectively treats insomnia, and shows additional benefits of reducing cellular and genomic markers of inflammation, and increasing anti-viral genomic markers in breast cancer survivors with insomnia. Tai Chi, as compared to CBT-I, yields greater and more durable decreases in systemic- and cellular inflammation. Targeting insomnia might mitigate the risk of inflammation-related co-morbidities in breast cancer survivors.

Anti-insomnia Effect of a Polyherbal Formulation on P-chlorophenyalanine Induced Experimental Animal Model.

Sleep is a dynamic and controlled set of physiological and behavioural practices during which the stabilisation and restoration processes of the body take place properly. Therefore, sleep disorders, especially chronic insomnia, can harm an individual's physical and mental health. However, the therapeutic alternatives are limited and possess severe side effects. Thus, in this study, we aimed to investigate the anti-insomnia effect of a polyherbal formulation (Sleep) (SLP) on p-chlorophenyalanine (PCPA) induced insomnia in rats. Intraperitoneal injection of PCPA induced the experimental condition, and the therapeutic effect of SLP was evaluated by studying the sleep pattern and expression of various neurotransmitters and receptors, along with neurotrophins. Moreover, insomnia-associated oxidative stress and inflammation were also studied. From the findings, we found that the SLP-supplemented animals improved their sleeping behaviour and that the major neurotransmitters, hormones, and receptors were maintained at an equilibrium level. Furthermore, the neurotrophin level was increased and pro-inflammatory cytokines were reduced. The evaluation of oxidative stress markers shows that the antioxidants were significantly boosted, and as a result, lipid peroxidation was prevented. The overall findings suggest that SLP can be used as an effective medication for the treatment of sleep disorders like insomnia as it triggers the major neurotransmitter system.

Study of the different sleep disturbances during the prodromal phase of depression and mania in bipolar disorders.

BACKGROUND: One of the challenges in bipolar disorder (BD) lies in early detection of the illness and its recurrences, to improve prognosis. Sleep disturbances (SD) have been proposed as reliable predictive markers of conversion. While preliminary studies have explored the relationship between SD and the onset of mood episodes, the results remain heterogeneous and a few have specifically examined patients' perception of prodromal symptoms and their progression until the episode occurs. Identifying prodromes represents a crucial clinical challenge, as it enables early intervention, thereby reducing the severity of BD. Therefore, the objective of this study is to better characterize and evaluate the progressive nature of SD as prodromal symptoms of mood episodes, and patients' perception of it. METHODS: Patients diagnosed with BD, either hospitalized or seeking treatment for a (hypo)manic or depressive episode benefited from standardized questionnaires, structured interviews, and self-report questionnaires to evaluate SD prior to the current episode, as well as sociodemographic and clinical information. RESULTS: Out of the 41 patients included, 59% spontaneously reported SD prior to the episode, appearing 90 days before depression and 35 days before mania (pre-indexed/spontaneous reports: 51.22% insomnia complaints, 4.88% hypersomnolence complaints, 7.32% parasomnias, 2.44% sleep movements). After inquiry about specific SD, the percentage of patients reporting prodromal SD increased significantly to 83%, appearing 210 days before depression and 112.5 days before mania (post-indexed reports: 75.61% presented with insomnia complaints appearing 150 days before depression and 20 days before mania, 46.34% had hypersomnolence complaints appearing 60 days before depression, 43.9% had parasomnias appearing 210 days before depression and 22.5 days before mania, 36.59% had sleep movements appearing 120 days before depression and 150 days before mania). Of note, bruxism appeared in 35% of patients before mania, and restless legs syndrome in 20% of patients before depression. CONCLUSION: This study highlights the very high prevalence of SD prior to a mood episode in patients with BD with differences between depressive and manic episodes. The more systematic screening of sleep alterations of the prodromal phase improved the recognition and characterization of different symptoms onset by patients. This underscores the need for precise questioning regarding sleep patterns in patients, to better identify the moment of transition toward a mood episode, referred to as "Chronos syndrome". The study emphasizes the importance of educating patients about the disorder and its sleep prodromal symptoms to facilitate early intervention and prevent recurrences.

The interaction between polygenic risk and environmental influences: A direct test of the 3P model of insomnia in adolescents.

BACKGROUND: Stress is a universal phenomenon and one of the most common precipitants of insomnia. However, not everyone develops insomnia after experiencing a stressful life event. This study aims to test aspects of Spielman's '3P model of insomnia' (during adolescence) by exploring the extent to which: (a) insomnia symptoms are predicted by polygenic scores (PGS); (b) life events predict insomnia symptoms; (c) the interaction between PGS and life events contribute to the prediction of insomnia symptoms; (d) gene-environment interaction effects remain after controlling for sex. METHODS: The sample comprised 4,629 twins aged 16 from the Twin Early Development Study who reported on their insomnia symptoms and life events. PGS for insomnia were calculated. In order to test the main hypothesis of this study (a significant interaction between PGS and negative life events), we fitted a series of mixed effect regressions. RESULTS: The best fit was provided by the model including sex, PGS for insomnia, negative life events, and their interactions (AIC = 26,158.7). Our results show that the association between insomnia symptoms and negative life events is stronger for those with a higher genetic risk for insomnia. CONCLUSIONS: This work sheds light on the complex relationship between genetic and environmental factors implicated for insomnia. This study has tested for the first time the interaction between genetic predisposition (PGS) for insomnia and environmental stressors (negative life events) in adolescents. This work represents a direct test of components of Spielman's 3P model for insomnia which is supported by our results.

Are some children genetically predisposed to poor sleep? A polygenic risk study in the general population.

BACKGROUND: Twin studies show moderate heritability of sleep traits: 40% for insomnia symptoms and 46% for sleep duration. Genome-wide association studies (GWAS) have identified genetic variants involved in insomnia and sleep duration in adults, but it is unknown whether these variants affect sleep during early development. We assessed whether polygenic risk scores for insomnia (PRS-I) and sleep duration (PRS-SD) affect sleep throughout early childhood to adolescence. METHODS: We included 2,458 children of European ancestry (51% girls). Insomnia-related items of the Child Behavior Checklist were reported by mothers at child's age 1.5, 3, and 6 years. At 10-15 years, the Sleep Disturbance Scale for Children and actigraphy were assessed in a subsample (N = 975). Standardized PRS-I and PRS-SD (higher scores indicate genetic susceptibility for insomnia and longer sleep duration, respectively) were computed at multiple p-value thresholds based on largest GWAS to date. RESULTS: Children with higher PRS-I had more insomnia-related sleep problems between 1.5 and 15 years (BPRS-I < 0.001 = .09, 95% CI: 0.05; 0.14). PRS-SD was not associated with mother-reported sleep problems. A higher PRS-SD was in turn associated with longer actigraphically estimated sleep duration (BPRS-SD < 5e08 = .05, 95% CI: 0.001; 0.09) and more wake after sleep onset (BPRS-SD < 0.005 = .25, 95% CI: 0.04; 0.47) at 10-15 years, but these associations did not survive multiple testing correction. CONCLUSIONS: Children who are genetically predisposed to insomnia have more insomnia-like sleep problems, whereas those who are genetically predisposed to longer sleep have longer sleep duration, but are also more awake during the night in adolescence. This indicates that polygenic risk for sleep traits, based on GWAS in adults, affects sleep already in children.

Pain in your day? Get sleep treatment anyway! The role of pain in insomnia treatment efficacy in women veterans.

Insomnia and pain disorders are among the most common conditions affecting United States adults and veterans, and their comorbidity can cause detrimental effects to quality of life among other factors. Cognitive behavioural therapy for insomnia and related behavioural therapies are recommended treatments for insomnia, but chronic pain may hinder treatment benefit. Prior research has not addressed how pain impacts the effects of behavioural insomnia treatment in United States women veterans. Using data from a comparative effectiveness clinical trial of two insomnia behavioural treatments (both including sleep restriction, stimulus control, and sleep hygiene education), we examined the impact of pain severity and pain interference on sleep improvements from baseline to post-treatment and 3-month follow-up. We found no significant moderation effects of pain severity or interference in the relationship between treatment phase and sleep outcomes. Findings highlight opportunities for using behavioural sleep interventions in patients, particularly women veterans, with comorbid pain and insomnia, and highlight areas for future research.

Prenatal insomnia disorder may predict concurrent and postpartum psychopathology: A longitudinal study.

While insomnia symptoms may be a risk factor for mental disturbances, few studies evaluated "Insomnia Disorder" and its relationship with perinatal psychopathology. Pregnant women were recruited during their last routine assessment before being hospitalized for delivery during the 3rd trimester at the Gynaecological Unit of the University Hospital of Ferrara and Udine, Italy, from January 2022 to January 2023. Our assessment included baseline evaluation (T0), and evaluations at 1 month (T1) and 3 months (T2) in the postpartum period, with specific questionnaires for insomnia disorder, such as Sleep Condition Indicator, mood and anxiety symptoms and psychosocial functioning, such as Edinburgh Postnatal Depression Scale, Mood Disorder Questionnaire, State-Trait Anxiety Inventory, Work and Social Adjustment Scale. At T0, 181 pregnant women were included. Insomnia disorder affected 22.3% at T0, 23.5% at T1 and 16.2% at T2. Women with insomnia disorder at baseline were significantly more affected by concurrent anxiety and depressive symptoms, had higher bipolar diathesis and poorer psychosocial functioning in the perinatal period. Prenatal insomnia disorder predicted anxiety (T0: odds ratio 4.44, p << 0.001; T1: odds ratio 4.009, p = 0.042) and depressive symptoms (T0: odds ratio 2.66, p = 0.015; T1: odds ratio 11.20, p = 0.001; T2: odds ratio 12.50 p = 0.049) in both the prenatal and postnatal period. It also predicted poor psychosocial function during the prenatal (odds ratio 3.55, p = 0.003) and postpartum periods (T1: odds ratio 2.33, p = 0.004). Insomnia disorder is emerging as an important prenatal factor that may contribute to concurrent and postpartum psychopathology.

States of consciousness and interoceptive hypersensibility: A study in patients with insomnia disorder.

This exploratory study aimed to investigate the relationship between interoceptive sensibility and quality of consciousness in individuals with insomnia disorder, in order to understand how the modulation of internal states may contribute to modifying the experience of consciousness during sleep difficulties. A total of 37 patients with insomnia disorder (mean age = 46.05 ± 18.16) and 41 healthy good sleepers (mean age = 50.2 ± 12.99) underwent a psychometric sleep and interoceptive sensibility assessment, using Insomnia Severity Index (ISI), Pittsburgh Sleep Quality Index (PSQI), and Multidimensional Assessment of Interoceptive Awareness (MAIA). Moreover, patients with insomnia disorder also completed a quality of consciousness evaluation, using the Phenomenology of Consciousness Inventory (PCI). Patients with insomnia disorder exhibited heightened interoceptive sensibility, particularly in noticing body sensations (p < 0.0001) and emotional awareness (p = 0.032), along with diminished abilities in attention regulation (p = 0.040), not-worrying (p = 0.001), and trusting (p = 0.002). Furthermore, correlations between interoceptive sensibility and multiple aspects of the consciousness state during the insomnia night were identified. Specifically, higher emotional awareness was linked to a 2.49-fold increase in the likelihood of subjectively experiencing altered consciousness states during insomnia. The study sheds light on the relationship between interoceptive sensibility and the subjective state of consciousness during insomnia, emphasising the importance of exploring and considering interoception as part of the therapeutic process for insomnia disorder. Given the exploratory nature of the study and the increased risk of type-I error from numerous correlations, the results should be interpreted with caution. Further research is needed to validate and confirm their robustness.