Sleep system sensitization: evidence for changing roles of etiological factors in insomnia

The sleep response to stress: how sleep reactivity can help us prevent insomnia and promote resilience to trauma

Sleep reactivity is a predisposition to sleep disturbance during environmental perturbations, pharmacological challenges, or stressful life events. Consequently, individuals with highly reactive sleep systems are prone to insomnia disorder after a stressor, engendering risk of psychopathology and potentially impeding recovery from traumatic stress. Thus, there is tremendous value in ameliorating sleep reactivity to foster a sleep system that is robust to stress exposure, ultimately preventing insomnia and its downstream consequences. We reviewed prospective evidence for sleep reactivity as a predisposition to insomnia since our last review on the topic in 2017. We also reviewed studies investigating pre-trauma sleep reactivity as a predictor of adverse post-traumatic sequelae, and clinical trials that reported the effect of behavioural treatments for insomnia on mitigating sleep reactivity. Most studies measured sleep reactivity via self-report using the Ford Insomnia Response to Stress Test (FIRST), demonstrating high scores on this scale reliably indicate a sleep system with a lower capacity to tolerate stress. Nascent evidence suggests elevated sleep reactivity prior to trauma increases the risk of negative posttraumatic outcomes, namely acute stress disorder, depression, and post-traumatic stress disorder. Lastly, sleep reactivity appears most responsive to behavioural insomnia interventions when delivered early during the acute phase of insomnia. Overall, the literature strongly supports sleep reactivity as a premorbid vulnerability to incident acute insomnia disorder when faced with an array of biopsychosocial stressors. The FIRST identifies individuals at risk of insomnia a priori, thereby guiding early interventions toward this vulnerable population to prevent insomnia and promote resilience to adversity.

"Life will never be the same": a qualitative analysis of the impact of COVID-19 on adults with a history of insomnia

Study Objectives

To utilize qualitative data analysis to enrich our understanding of the impact of coronavirus (COVID-19) on those with a pre-pandemic history of insomnia.

Methods

The sample included 208 participants who completed the Coronavirus Impact Scale in April and May 2020. A content analysis was used to analyze responses to a free-response item "Please tell us about any other ways the coronavirus has impacted your life" (n = 175), using a combination of inductive and deductive coding.

Results

Both negative and positive themes emerged, including altered access to health care, negative financial impacts, and various emotions surrounding COVID-19. Some shared "silver linings" such as having more time for physical activity and deepening familial connections.

Conclusions

This analysis provides novel insight into the shared concerns and lived experiences of those with a history of insomnia. Understanding these unique stressors can enable healthcare professionals to better anticipate the needs of this population, as well as learn to navigate future stressful events.

Longitudinal trajectories of sleep quality in correlation with maltreatment in early childhood: A cohort of Chinese early adolescents

BACKGROUND

Child maltreatment may lead to sleep disturbance during the critical period of child development. Our study examined the effect of maltreatment in early childhood on trajectories of sleep quality among early adolescents.

METHODS

The study included 1611 participants (mean ± standard deviation age at baseline: 12.5 ± 0.5 years) from a middle school in southeastern China. Of these participants, 60.5 % were males. Information on early childhood maltreatment during pre-seventh grade was obtained through a self-report questionnaire at baseline, and sleep quality was collected at baseline and during follow-up. We used a group-based trajectory model to characterize trajectories of sleep quality.

RESULTS

The study identified four trajectories of sleep quality, namely the low sleep score group (25.0 %), the moderate-low sleep score group (51.0 %), the moderate-increasing sleep score (17.0 %), and the high-decreasing sleep score (7.0 %) group. After adjusting for covariates, the findings revealed that emotional abuse and physical abuse were associated with an increased risk of developing new-onset sleep disturbances in early adolescents. Particularly, emotional abuse (incidence rate ratio = 1.71, 95 % confidence interval: 1.08-2.71) significantly increased the risk of belonging to the high-decreasing sleep score group. Moreover, there existed a dose-response relationship between early childhood maltreatment and sleep quality trajectories, with a higher number of maltreatment types in early childhood correlating with a greater risk of belonging to the high-decreasing sleep score group.

CONCLUSIONS

The findings of our study provide compelling evidence indicating that specific types and cumulative maltreatment during early childhood contribute to sleep disturbances among early adolescents. The study findings highlight the significance of preventing and reducing early childhood maltreatment to enhance sleep quality during early adolescence.

Sleep reactivity is associated with social anxiety and disordered-eating behaviors in college students

Objective: Investigate whether sleep reactivity was associated with social anxiety and disordered-eating behaviors in a college population. Participants: One hundred ninety-eight college-age men and women. Methods: Participants completed self-report measures of social anxiety, disordered-eating behaviors and sleep reactivity. Results: Sleep reactivity was associated with greater dietary restriction and purging, controlling for social anxiety but it was not associated with binge eating. Sleep reactivity was associated with elevated symptoms of social anxiety, controlling for disordered-eating behaviors. Conclusions: The results suggest that sleep reactivity represents a shared correlate of disordered-eating behaviors and social anxiety that may partially explain their co-occurrence. Interventions to help college students high in sleep reactivity effectively manage stress and regulate their sleep may aid in the prevention and treatment of social anxiety and disordered-eating behaviors.

Insomnia and common mental disorder among patients with pre-existing chronic non-communicable diseases in southern Ethiopia: a survey during COVID-19 pandemic

Background

COVID-19 has been causing significant mental health problems and other health-related issues. Despite the fact that COVID-19 has a significant impact on chronic disease patients, there is scant research on insomnia, common mental health disorders (CMD), and their associated factors among chronic disease patients.

Objective

The purpose of this study was to assess the prevalence of insomnia and common mental disorders (CMD) and their associated factors among patients with pre-existing chronic NCDs in Sidama, southern Ethiopia.

Methods

A multicenter cross-sectional study was undertaken between June 1 and September 1, 2021. The study included 633 participants. CMD and insomnia were assessed using a 20-item Self-Reported Questionnaire (SRQ-20) and a 7-item Insomnia Severity Index (ISI) scale, respectively. To describe the various variables, descriptive statistics were used. We performed multivariable logistic regression analysis to identify independent factors associated with CMD and insomnia. A value of p < 0.05 was considered statistically significant at a 95% confidence interval.

Results

The prevalence of insomnia and CMD was found to be 39.3% and 46.8%, respectively. Being merchant (AOR = 0.33; 95% CI = 0.13, 0.82), having a diagnosis of diabetes mellitus (AOR = 1.89; 95% CI = 1.04, 3.46), comorbid diagnosis (AOR = 3.96; 95% CI = 2.27, 6.89), low social support (poor (AOR = 3.37; 95% CI = 1.51, 7.57) and moderate (AOR = 3.13; 95% CI = 1.46, 6.69)), symptoms of insomnia (AOR = 12.08; 95% CI = 7.41, 19.72) and poor quality of life (QOL) (AOR = 1.67; 95% CI = 1.04, 2.72) were independent predictors of CMD. We also found out that, having cardiovascular disorders (CVDs) (AOR = 2.48; 95% CI = 1.18, 5.19), CMD (AOR = 12.09; 95% CI = 7.46, 19.61), and poor QOL (AOR = 2.04; 95% CI = 1.27, 3.26) were significantly associated with insomnia symptoms.

Conclusion

Our study suggests that substantially high prevalence of CMD and insomnia. Significant association between CMD and occupation, diagnosis, comorbidity, social support, insomnia, and QOL were found. We also revealed that having CVDs, CMD, and poor QOL were significantly associated with insomnia symptoms. Therefore, dealing with the mental health problems of patients with chronic NCDs is an essential component of public health intervention during the COVID-19 pandemic.

Improved resilience following digital cognitive behavioral therapy for insomnia protects against insomnia and depression one year later

BACKGROUND

While the negative consequences of insomnia are well-documented, a strengths-based understanding of how sleep can increase health promotion is still emerging and much-needed. Correlational evidence has connected sleep and insomnia to resilience; however, this relationship has not yet been experimentally tested. This study examined resilience as a mediator of treatment outcomes in a randomized clinical trial with insomnia patients.

METHODS

Participants were randomized to either digital cognitive behavioral therapy for insomnia (dCBT-I; n = 358) or sleep education control (n = 300), and assessed at pre-treatment, post-treatment, and 1-year follow-up. A structural equation modeling framework was utilized to test resilience as a mediator of insomnia and depression. Risk for insomnia and depression was also tested in the model, operationalized as a latent factor with sleep reactivity, stress, and rumination as indicators (aligned with the 3-P model). Sensitivity analyses tested the impact of change in resilience on the insomnia relapse and incident depression at 1-year follow-up.

RESULTS

dCBT-I resulted in greater improvements in resilience compared to the sleep education control. Furthermore, improved resilience following dCBT-I lowered latent risk, which was further associated with reduced insomnia and depression at 1-year follow-up. Sensitivity analyses indicated that each point improvement in resilience following treatment reduced the odds of insomnia relapse and incident depression 1 year later by 76% and 65%, respectively.

CONCLUSIONS

Improved resilience is likely a contributing mechanism to treatment gains following insomnia therapy, which may then reduce longer-term risk for insomnia relapse and depression.

Association of Sleep Reactivity and Anxiety Sensitivity with Insomnia-Related Depression and Anxiety among City Government Employees in Japan

It has recently been noted that a reduction in sleep reactivity, characterized as the trait-like degree to which exposure to stress interferes with sleep, and anxiety sensitivity are associated with reduced insomnia severity. This study aimed to examine whether sleep reactivity and anxiety sensitivity are associated with insomnia-related depression and anxiety among city government employees in Japan. This cross-sectional study included 1810 city government employees of Koka City, Japan (mean age (standard deviation): 45.33 (12.20) years) who completely answered the scales for sleep reactivity, anxiety sensitivity, anxiety, and depression. Stepwise multiple regression analysis adjusted for demographic data showed that anxiety sensitivity (β = 0.39) was significantly linked to anxiety, and sleep reactivity (β = 0.36) was significantly linked to depression in individuals with insomnia. Additionally, the results of a logistic regression analysis adjusted for demographic data showed that anxiety sensitivity and sleep reactivity were relevant factors for anxious insomnia (OR = 12.69) and depressive insomnia (OR = 8.73), respectively. Whereas both sleep reactivity (OR = 14.67) and anxiety sensitivity (OR = 6.14) were associated with combined insomnia. These findings indicate that sleep reactivity is strongly associated with depressive symptoms, and anxiety sensitivity is strongly associated with anxiety symptoms in individuals with insomnia.

Phenotypic divergence in sleep and circadian cycles linked by affective state and environmental risk related to psychosis

STUDY OBJECTIVES

Environmental cues influence circadian rhythm timing and neurochemicals involved in the regulation of affective behavior. How this interplay makes them a probable nonspecific risk factor for psychosis is unclear. We aimed to identify the relationship between environmental risk for psychosis and circadian timing phenotypes sampled from the general population.

METHODS

Using an online survey, we devised a cumulative risk exposure score for each of the 1898 survey respondents based on 23 empirically verified transdiagnostic risks for psychosis, three dimensions of affect severity, psychotic-like experiences, and help-seeking behavior. Quantitative phenotyping of sleep and circadian rhythms was undertaken using at-home polysomnography, melatonin and cortisol profiles, and 3-week rest-activity behavior in individuals with a high-risk exposure load (top 15% of survey respondents, n = 22) and low-risk exposure load (bottom 15% of respondents, n = 22).

RESULTS

Psychiatric symptoms were present in 100% of the high-load participants and 14% of the low-load participants. Compared to those with a low-load, high-load participants showed a later melatonin phase which was reflected by a greater degree of dispersion in circadian timing. Phase relationships between later circadian melatonin phase and later actigraphic sleep onsets were maintained and these were strongly correlated with self-reported sleep mid-points. No differences were identified from polysomnography during sleep between groups.

CONCLUSION

Distinguishing circadian timing from other sleep phenotypes will allow adaptation for dosage of time-directed intervention, useful in stabilizing circadian timekeeping physiology and potentially reducing the multisystemic disruption in mental health disorders.

Insomnia is a key risk factor for persistent anxiety and depressive symptoms: A 12-month longitudinal cohort study during the COVID-19 pandemic

BACKGROUND

Insomnia is a risk factor for affective disorders. This study examined whether individuals with insomnia symptoms early in the pandemic, either pre-existing or new-onset, were more vulnerable to anxiety and depressive symptoms over time than those who maintained normal sleep. Additionally, sleep-related factors such as pre-sleep arousal were assessed for their influence on clinically significant anxiety and depression risk.

METHODS

Using a global online survey with 3-, 6-, and 12-month follow-ups between April 2020 and May 2021, data from 2069 participants (M = 46.16 ± 13.42 years; 75.3 % female) with pre-existing, new-onset, or no insomnia symptoms was examined using mixed-effects and logistic regression models.

RESULTS

New-onset and pre-existing insomnia predicted persistent anxiety and depressive symptoms longitudinally (p's < 0.001), over other known risk factors, including age, sex, and previous psychiatric diagnoses. Anxiety and depressive symptoms in both insomnia groups remained above clinically significant thresholds at most time points, whereas normal sleepers remained subclinical. Pre-sleep arousal was found to increase the risk of clinically significant anxiety (OR = 1.05) and depressive symptoms (OR = 1.09) at 12-months. Sleep effort contributed to anxiety (OR = 1.06), whereas dysfunctional sleep-related beliefs and attitudes predicted clinically significant depression (OR = 1.22).

LIMITATIONS

Insomnia group categorization was based on self-report at baseline supported by a validated measure. High participant attrition was observed at 3-months (53 %; n = 971), but retention remained steady till 12-months (63 %, n = 779).

CONCLUSIONS

Insomnia is a modifiable risk factor for persistent anxiety and depressive symptoms that needs to be addressed in mental healthcare. Additionally, pre-sleep arousal may be an important transdiagnostic process linking insomnia with affective disorders.

Restraint stress induced anxiety and sleep in mice

In humans and animals, exposure to changes in internal or external environments causes acute stress, which changes sleep and enhances neurochemical, neuroendocrine, and sympathetic activities. Repeated stress responses play an essential role in the pathogenesis of psychiatric diseases and sleep disorders. However, the underlying mechanism of sleep changes and anxiety disorders in response to acute stress is not well established. In the current study, the effects of restraint stress (RS) on anxiety and sleep-wake cycles in mice were investigated. We found that after RS, the mice showed anxiety-like behavior after RS manipulation and increased the amounts of both non-rapid eye movement (NREM) and rapid eye movement (REM) sleep in the dark period. The increase in sleep time was mainly due to the increased number of episodes of NREM and REM sleep during the dark period. In addition, the mice showed an elevation of the EEG power spectrum of both NREM and REM sleep 2 h after RS manipulation. There was a significant reduction in the EEG power spectrum of both NREM and REM sleep during the darkperiod in the RS condition. The expression of the c-Fos protein was significantly increased in the parabrachial nucleus, bed nucleus of the stria terminalis, central amygdala, and paraventricular hypothalamus by RS manipulation. Altogether, the findings from the present study indicated that neural circuits from the parabrachial nucleus might regulate anxiety and sleep responses to acute stress, and suggest a potential therapeutic target for RS induced anxiety and sleep alterations.

Pre-pandemic sleep reactivity prospectively predicts distress during the COVID-19 pandemic: The protective effect of insomnia treatment

The COVID-19 pandemic is a rare stressor that has precipitated an accompanying mental health crisis. Prospective studies traversing the pandemic's onset can elucidate how pre-existing disease vulnerabilities augured risk for later stress-related morbidity. We examined how pre-pandemic sleep reactivity predicted maladaptive stress reactions and depressive symptoms in response to, and during, the pandemic. This study is a secondary analysis of a randomised controlled trial from 2016 to 2017 comparing digital cognitive behavioural therapy for insomnia (dCBT-I) against sleep education (N = 208). Thus, we also assessed whether dCBT-I moderated the association between pre-pandemic sleep reactivity and pandemic-related distress. Pre-pandemic sleep reactivity was measured at baseline using the Ford Insomnia Response to Stress Test. In April 2020, participants were recontacted to report pandemic-related distress (stress reactions and depression). Controlling for the treatment condition and the degree of COVID-19 impact, higher pre-pandemic sleep reactivity predicted more stress reactions (β = 0.13, ± 0.07 SE, p = 0.045) and depression (β = 0.22, ± 0.07 SE, p = 0.001) during the pandemic. Further, the odds of reporting clinically significant stress reactions and depression during the pandemic were over twice as high in those with high pre-pandemic sleep reactivity. Notably, receiving dCBT-I in 2016-2017 mitigated the relationship between pre-pandemic sleep reactivity and later stress reactions (but not depression). Pre-pandemic sleep reactivity predicted psychological distress 3-4 years later during the COVID-19 pandemic, and dCBT-I attenuated its association with stress reactions, specifically. Sleep reactivity may inform prevention and treatment efforts by identifying individuals at risk of impairment following stressful events.

Sleep Disturbances During the Menopausal Transition: The Role of Sleep Reactivity and Arousal Predisposition

BACKGROUND

Sleep disturbances are common during the menopausal transition and several factors can contribute to this increased incidence. This study examined the association between sleep reactivity, arousal predisposition, sleep disturbances, and menopause.

METHODS

Data for this study were derived from a longitudinal, population-based study on the natural history of insomnia. A total of 873 women (40-60 years) were divided into two groups according to their menopausal status at baseline: reproductive (n = 408) and postmenopausal (n = 465). Participants were evaluated annually throughout the five-year follow-up period. Four questionnaires were used to examine sleep quality, insomnia severity, sleep reactivity, and arousal predisposition. The data were analyzed using two approaches: cross-sectional with a multivariate analysis and binary regression, and longitudinal with a linear mixed models using menopausal groups (3) x time (5) design.

RESULTS

Cross-sectional analyses showed that postmenopausal women reported significantly more severe insomnia and poorer sleep quality than reproductive women. Sleep reactivity and arousal predisposition were significant predictors of sleep disturbances. Longitudinal analyses revealed increased sleep disturbances in the two years before and after the menopausal transition. Sleep reactivity and arousal predisposition did not moderate the temporal relationship between menopausal transition and sleep disturbances.

CONCLUSION

More sleep disturbances were reported during the menopausal transition, but those difficulties were not explained by sleep reactivity and arousal predisposition. These results suggest the involvement of other psychophysiological factors in the development of sleep disturbances during the menopause.

Differences in Treatment Effects of Cognitive-behavioral Therapy for Insomnia Based on Sleep Reactivity: A Preliminary Study

INTRODUCTION

Sleep reactivity is the trait-like degree to which stress disrupts sleep, resulting in difficulty falling and staying asleep. Although previous studies have suggested that individuals who have high sleep reactivity may be resistant to cognitive-behavioral therapy for insomnia (CBT-I) effects, there have been no studies that have investigated this empirically. This study explored differential treatment responses in CBT-I based on sleep reactivity levels.

MATERIAL AND METHOD

Participants for this study were nineteen insomnia patients who met DSM-5 criteria for insomnia disorder. All participants received four weekly sessions of structured cognitive-behavioral therapy for insomnia (CBT-I). Individuals completed the Insomnia Severity Index (ISI), Korean version of Center for Epidemiologic Studies Depression Scale-Revised (K-CESD-R), Ford Insomnia Response to Stress Test (FIRST), Dysfunctional Beliefs and Attitudes about Sleep Scale-16 (DBAS-16), the Daily Inventory of Stressful Events (DISE) and a sleep diary. Participants were classified into two groups based on sleep reactivity level (high and low sleep reactivity).

RESULT

Following treatment, significant changes were found for ISI, K-CESD-R, DBAS-16 and FIRST scores, sleep onset latency, wake after sleep onset, sleep efficiency, number of awakenings, sleep quality and feeling refreshed upon awakening in both groups. Improvements in sleep efficiency was lower in the high sleep reactivity group compared to the low sleep reactivity group. No differences in ISI, K-CESD-R, DBAS-16 scores, and stress event frequency during the treatment duration were found between groups.

CONCLUSION

These findings suggest that sleep reactivity level may be an important factor that affects treatment outcome of CBT-I. Furthermore, the results may suggest that individual response to stress events are more important than the stressor itself.

Proteomics Reveals Molecular Changes in Insomnia Patients with More Dreams

Background

Insomnia is a sleep disorder and the cause of many healthy problems. However, there are few studies on patients with insomnia and dreaminess at present. Therefore, this study is aimed at exploring the pathological molecular mechanisms and potential diagnostic and therapeutic targets related to insomnia patients with more dreams.

Methods

Sleep characteristics of 36 primary insomnia patients with more dreams and 36 well sleeping participants were assessed using polysomnography (PSG) and Pittsburgh Sleep Quality Index (PSQI). Serum samples from 9 insomnia patients and 9 controls were randomly selected for proteomic detection. Differentially expressed proteins (DEPs) between the two groups were identified; enrichment analysis and PPI network were performed. The top 10 most connected proteins in the PPI network were subjected to targeted drug prediction and screened key proteins. Proteins with targeted drugs were recognized as key proteins and subjected to ELISA detection.

Results

Insomnia patients had a distinct REM behavior disorder signature compared with controls. Proteomic sequencing identified 76 DEPs. Enrichment analysis found that DEPs were significantly enriched in the complement and coagulation cascades. Metabolic responses were also activated in insomnia patients. Among the hub proteins screened in the PPI network, APOA1, APOB, F2, and SPARC may be targeted by many herbal medicines and considered as key proteins. ELISA assays validated their differential expression between insomnia and controls.

Conclusion

In this study, we identified the potential key proteins of insomnia patients with more dreams. The pathological process may associate with inflammation and metabolic response. These results provide molecular targets for diagnostic and therapeutic targets. The results of our analysis suggest that the expression changes of key proteins have a good predictive diagnostic role for the occurrence of insomnia with more dreams in patients.

Sleep disorders mediate the link between childhood trauma and depression severity in children and adolescents with depression

BACKGROUND

Childhood trauma is closely related to the onset of depression and more severe depressive symptoms; however, the specific mechanisms are unclear. We aimed to examine the relationship between childhood trauma and sleep disorders in children and adolescents with depression and to explore further the role of sleep disorders in the relationship between childhood trauma and depression severity.

METHODS

A total of 285 children and adolescents with depression completed all scale assessments, including the Childhood Trauma Questionnaire, Self-Reported Insomnia Severity Index and Epworth Sleepiness Scale, and the Center for Epidemiologic Studies Depression Scale. A simple mediation model was used as a theoretical model to examine whether sleep disorders could mediate the relationship between childhood trauma and depression severity.

RESULTS

Among children and adolescents with depression, childhood trauma is about 78.9%. Compared with patients without childhood trauma, patients with childhood trauma had a higher incidence of sleep disorders (Z = 17.59, P < 0.001), which were characterized by insomnia (Z = 14.45, P < 0.001), not hypersomnia (Z = 2.77, P = 0.096). Different childhood trauma subtypes significantly affected sleep disorders and insomnia (all P < 0.05). Insomnia partially mediated the relationship between childhood trauma and depression severity, and the mediating effect accounted for 35.90%.

CONCLUSION

This study found a high rate of concurrent childhood trauma and insomnia among children and adolescents with depression. Insomnia, as a mediator between childhood trauma and depression severity, partially mediates the relationship.

Internet-delivered CBT intervention (Space for Sleep) for insomnia in a routine care setting: Results from an open pilot study

Insomnia is a highly prevalent, often comorbid disorder associated with difficulties sleeping, remaining awake, and impaired quality of life. Internet-delivered Cognitive Behavioral Therapy for insomnia (ICBT-I) has the potential to help large numbers of people with sleep disorders. This study investigated the preliminary effects of an 8-week guided ICBT-I intervention within a routine stepped-care service. Fifty-six (N = 56) patients consented to participate. The primary outcome was assessed using the Insomnia Severity Index (ISI) and secondary outcome measures included the Patient Health Questionnaire 9-item (PHQ-9), Generalized Anxiety Disorder 7-item (GAD-7), and the Work and Social Adjustment Scale (WSAS), each administered at baseline and weekly thereafter. Intention-to-treat analyses indicated that ICBT-I produced statistically significant pre- to post- reductions in symptoms of insomnia, yielding within-group effects of d = 0.82 suggesting a potential for improved outcomes. Similar improvements were seen across secondary outcomes, with small-to-medium post-treatment within-group effects observed: depression (d = 0.63), anxiety (d = 0.39), and functional impairment (d = 0.31). These findings are supportive of the intervention's potential effectiveness and speak to the importance of several implementation factors that could enhance the effects of the intervention. The results contribute to the growing evidence base for digital interventions designed to help those with sleep difficulties and will inform the design of a future controlled evaluation of ICBT-I under routine clinical settings.

Digital cognitive behavioral therapy for insomnia promotes later health resilience during the coronavirus disease 19 (COVID-19) pandemic

STUDY OBJECTIVES

Stressful life events contribute to insomnia, psychosocial functioning, and illness. Though individuals with a history of insomnia may be especially vulnerable during stressful life events, risk may be mitigated by prior intervention. This study evaluated the effect of prior digital cognitive-behavioral therapy for insomnia (dCBT-I) versus sleep education on health resilience during the COVID-19 pandemic.

METHODS

COVID impact, insomnia, general- and COVID-related stress, depression, and global health were assessed in April 2020 in adults with a history of insomnia who completed a randomized controlled trial of dCBT-I (n = 102) versus sleep education control (n = 106) in 2016-2017. Regression analyses were used to evaluate the effect of intervention conditions on subsequent stress and health during the pandemic.

RESULTS

Insomnia symptoms were significantly associated with COVID-19 related disruptions, and those who previously received dCBT-I reported less insomnia symptoms, less general stress and COVID-related cognitive intrusions, less depression, and better global health than those who received sleep education. Moreover, the odds for resurgent insomnia was 51% lower in the dCBT-I versus control condition. Similarly, odds of moderate to severe depression during COVID-19 was 57% lower in the dCBT-I condition.

CONCLUSIONS

Those who received dCBT-I had increased health resilience during the COVID-19 pandemic in adults with a history of insomnia and ongoing mild to moderate mental health symptoms. These data provide evidence that dCBT-I is a powerful tool to promote mental and physical health during stressors, including the COVID-19 pandemic.

CLINICAL TRIAL REGISTRATION

NCT02988375.

Prior sleep problems and adverse post-traumatic neuropsychiatric sequelae of motor vehicle collision in the AURORA study

STUDY OBJECTIVES

Many patients in Emergency Departments (EDs) after motor vehicle collisions (MVCs) develop post-traumatic stress disorder (PTSD) or major depressive episode (MDE). This report from the AURORA study focuses on associations of pre-MVC sleep problems with these outcomes 8 weeks after MVC mediated through peritraumatic distress and dissociation and 2-week outcomes.

METHODS

A total of 666 AURORA patients completed self-report assessments in the ED and at 2 and 8 weeks after MVC. Peritraumatic distress, peritraumatic dissociation, and pre-MVC sleep characteristics (insomnia, nightmares, daytime sleepiness, and sleep duration in the 30 days before the MVC, trait sleep stress reactivity) were assessed retrospectively in the ED. The survey assessed acute stress disorder (ASD) and MDE at 2 weeks and at 8 weeks assessed PTSD and MDE (past 30 days). Control variables included demographics, MVC characteristics, and retrospective reports about PTSD and MDE in the 30 days before the MVC.

RESULTS

Prevalence estimates were 41.0% for 2-week ASD, 42.0% for 8-week PTSD, 30.5% for 2-week MDE, and 27.2% for 8-week MDE. Pre-MVC nightmares and sleep stress reactivity predicted 8-week PTSD (mediated through 2-week ASD) and MDE (mediated through the transition between 2-week and 8-week MDE). Pre-MVC insomnia predicted 8-week PTSD (mediated through 2-week ASD). Estimates of population attributable risk suggest that blocking effects of sleep disturbance might reduce prevalence of 8-week PTSD and MDE by as much as one-third.

CONCLUSIONS

Targeting disturbed sleep in the immediate aftermath of MVC might be one effective way of reducing MVC-related PTSD and MDE.

Stress-related sleep reactivity is associated with insomnia, psychopathology and suicidality in pregnant women: preliminary results

INTRODUCTION

Depression and anxiety symptoms are commonly experienced by women during pregnancy and may have negative consequences on mothers and newborns. Deterioration of sleep quality throughout pregnancy increases insomnia, which may lead to adverse outcomes including increased psychopathology in the perinatal period. Thus, identifying women at high risk of developing insomnia may have important clinical implications on maternal-fetal outcomes. Stress-related sleep reactivity is a well-established risk factor for future insomnia, depression, and anxiety in general adult samples. However, little is known of sleep reactivity and its relations to sleep and mood pathology in pregnancy. Therefore, we explored sleep reactivity in pregnant women and its relations to prenatal symptoms of insomnia, depression, anxiety, and suicidality.

METHOD

Sixty-two pregnant women (mean age 33.6 ± 3 years, 20.6 ± 0.6 weeks of pregnancy) were evaluated during their routine visit at the Gynecological Unit of the University of Pisa, Italy, using the Insomnia Severity Index (ISI) for insomnia symptoms, the Ford Insomnia Response to Stress Test for sleep reactivity (FIRST), Edinburgh Postnatal Depression Scale (EPDS) for depressive symptoms, and the Zung Self Rating Anxiety Scale (SAS) for anxiety symptoms. Item #10 of the EPDS was used to assess for suicidality. Differences in means between women with high vs low stress-related sleep reactivity were calculated using t-test or Mann-Whitney U/Wilcoxon test. Linear/multiple regression analyses have been performed to study associations between variables.

RESULTS

Pregnant women with high stress-related sleep reactivity, relative to those with low reactivity, reported greater symptoms of insomnia (t = 6.5, 0.004) as well as higher rates of depression (62.0% vs 6.1%, p < 0.001), anxiety (55.1% vs 15.1%, p = 0.030), and suicidality (17.2% vs 3.0%, p = 0.025). Multivariate models revealed sleep reactivity to correlate independently with symptoms of insomnia, depression, and anxiety, when controlling for comorbid symptoms.

CONCLUSIONS

In mid-pregnancy, women with high sleep reactivity report elevated symptoms of insomnia, depression, and anxiety, and are more likely to endorse suicidal ideation. As a prognostic marker of future insomnia and psychiatric illness, early detection of high prenatal sleep reactivity holds potential to prevent the development of sleep and mood pathology during pregnancy, thereby potentially improving maternal and child outcomes.

The impact of stress on sleep: Pathogenic sleep reactivity as a vulnerability to insomnia and circadian disorders

Sleep reactivity is the trait-like degree to which stress exposure disrupts sleep, resulting in difficulty falling and staying asleep. Individuals with highly reactive sleep systems experience drastic deterioration of sleep when stressed, whereas those with low sleep reactivity proceed largely unperturbed during stress. Research shows that genetics, familial history of insomnia, female gender and environmental stress influence how the sleep system responds to stress. Further work has identified neurobiological underpinnings for sleep reactivity involving disrupted cortical networks and dysregulation in the autonomic nervous system and hypothalamic-pituitary-adrenal axis. Sleep reactivity is most pathologically and clinically pertinent when in excess, such that high sleep reactivity predicts risk for future insomnia disorder, with early evidence suggesting high sleep reactivity corresponds to severe insomnia phenotypes (sleep onset insomnia and short sleep insomnia). High sleep reactivity is also linked to risk of shift-work disorder, depression and anxiety. Importantly, stress-related worry and rumination may exploit sensitive sleep systems, thereby augmenting the pathogenicity of sleep reactivity. With the development of cost-effective assessment of sleep reactivity, we can now identify individuals at risk of future insomnia, shift-work disorder and mental illness, thus identifying a target population for preventive intervention. Given that insomniacs with high sleep reactivity tend to present with severe insomnia phenotypes, patient sleep reactivity may inform triaging to different levels of treatment. Future research on sleep reactivity is needed to clarify its neurobiology, characterize its long-term prospective associations with insomnia and shift-work disorder phenotypes, and establish its prognostic value for mental illness and other non-sleep disorders.

Hyperarousal and sleep reactivity in insomnia: current insights

Hyperarousal is a key component in all modern etiological models of insomnia disorder. Overall patterns in the literature suggest that over-active neurobiological and psychological systems contribute to difficulty sleeping. Even so, mixed results regarding the specific mechanisms linking hyperarousal to sleep disturbance limit current etiological conceptualizations. Similar basal arousal profiles between individuals with high vs low risk for insomnia in the absence of stress exposure suggest that dysregulated stress "response" rather than general hyperarousal may be a more pertinent marker of risk. In this report, we discuss evidence for hyperarousal in insomnia and explore the role of sleep reactivity. A trait characteristic, sleep reactivity is the degree to which stress disrupts sleep, manifesting as difficulty falling and staying asleep. Premorbid sleep reactivity has been shown to identify individuals at risk for future insomnia disorder, such as highly reactive sleepers (whose sleep systems are sensitive to stress) who are at elevated disease risk. Research points to genetics, family history of insomnia, gender, and environmental stress as factors that influence sleep reactivity. Importantly, stress-related cognitive-emotional reactivity (e.g., rumination, worry) may exploit the vulnerability of a highly reactive sleep system. We propose that sleep reactivity and cognitive-emotional reactivity may share a bidirectional relationship, conferring an insalubrious environment for sleep in response to stress. Future research on sleep reactivity is needed to identify its neurobiology, characterize its relationship with cognitive-emotional reactivity, and explore the potential clinical utility of sleep reactivity in treatment planning.

Nocturnal insomnia symptoms and stress-induced cognitive intrusions in risk for depression: A 2-year prospective study

Nearly half of US adults endorse insomnia symptoms. Sleep problems increase risk for depression during stress, but the mechanisms are unclear. During high stress, individuals having difficulty falling or staying asleep may be vulnerable to cognitive intrusions after stressful events, given that the inability to sleep creates a period of unstructured and socially isolated time in bed. We investigated the unique and combined effects of insomnia symptoms and stress-induced cognitive intrusions on risk for incident depression. 1126 non-depressed US adults with no history of DSM-5 insomnia disorder completed 3 annual web-based surveys on sleep, stress, and depression. We examined whether nocturnal insomnia symptoms and stress-induced cognitive intrusions predicted depression 1y and 2y later. Finally, we compared depression-risk across four groups: non-perseverators with good sleep, non-perseverators with insomnia symptoms, perseverators with good sleep, and perseverators with insomnia symptoms. Insomnia symptoms (β = .10-.13, p < .001) and cognitive intrusions (β = .19-.20, p < .001) predicted depression severity 1y and 2y later. Depression incidence across 2 years was 6.2%. Perseverators with insomnia had the highest rates of depression (13.0%), whereas good sleeping non-perseverators had the lowest rates (3.3%, Relative Risk = 3.94). Perseverators with sleep latency >30 m reported greater depression than good sleeping perseverators (t = 2.09, p < .04). Cognitive intrusions following stress creates a depressogenic mindset, and nocturnal wakefulness may augment the effects of cognitive arousal on depression development. Poor sleepers may be especially vulnerable to cognitive intrusions when having difficulty initiating sleep. As treatable behaviors, nighttime wakefulness and cognitive arousal may be targeted to reduce risk for depression in poor sleepers.

DSM-5 Insomnia and Short Sleep: Comorbidity Landscape and Racial Disparities

STUDY OBJECTIVES

We estimated rates of cardiometabolic disease, pain conditions, and psychiatric illness associated with Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) insomnia disorder (current and in remission) and habitual short sleep (fewer than 6 h), and examined the roles of insomnia and short sleep in racial disparities in disease burden between black and non-Hispanic white Americans.

METHODS

This epidemiological survey study was cross-sectional. The community-based sample consisted of 3,911 subjects (46.0 y ± 13.3; 65.4% female; 25.0% black) across six sleep groups based on DSM-5 insomnia classification (never vs. remitted vs. current) and self-reported habitual sleep duration (normal vs. short). Vascular events, cardiometabolic disease, pain conditions, and psychiatric symptoms were self-reported.

RESULTS

Short sleeping insomniacs were at elevated risk for myocardial infarction, stroke, treated hypertension, diabetes, chronic pain, back pain, depression, and anxiety, independent of sex, age, and obesity. Morbidity profiles for insomniacs with normal sleep duration and former insomniacs, irrespective of sleep duration, were similar with elevations in treated hypertension, chronic pain, depression, and anxiety. Regarding racial disparities, cardiometabolic and psychiatric illness burden was greater for blacks, who were more likely to have short sleep and the short sleep insomnia phenotype. Evidence suggested that health disparities may be attributable in part to race-related differences in sleep.

CONCLUSIONS

Insomnia disorder with short sleep is the most severe phenotype of insomnia and comorbid with many cardiometabolic and psychiatric illnesses, whereas morbidity profiles are highly similar between insomniacs with normal sleep duration and former insomniacs. Short sleep endemic to black Americans increases risk for the short sleep insomnia phenotype and likely contributes to racial disparities in cardiometabolic disease and psychiatric illness.