Insomnia in the context of short sleep increases suicide risk

Study ObjectivesThe relationship between insomnia and suicide risk is not completely understood. We aimed to investigate the influence of insomnia on suicide risk, taking both sleep duration and depression into consideration.MethodsThe present study is based on a Swedish prospective cohort study of 38,786 participants with a mean follow-up time of 19.2 years. Cox proportional hazards models with attained age as time-scale were used to estimate hazard ratios (HRs) of death by suicide with 95% confidence intervals (CI) for participants categorized by frequency of insomnia symptoms. Causal mediation analysis was performed to assess to what extent the relationship between insomnia and suicide risk is mediated by depression.ResultsInsomnia was only associated with suicide risk among short sleepers, whereas no significant association was observed among those who slept 7 h/night or more. The total effect of insomnia in the context of short sleep on suicide risk, expressed on the HR scale, was 2.85 (95% CI 1.42–5.74). The direct effect was 2.25 (95% CI 1.12–4.54) and the indirect effect, mediated by depression, was 1.27 (95% CI 1.05–1.53). Of the total effect, 32% was mediated by depression. The association between insomnia and suicide risk became more pronounced with decreasing depressive symptoms (p value for trend <0.05).ConclusionsInsomnia in the context of short sleep increases suicide risk, both directly and indirectly by affecting the risk of depression. Abnormalities of sleep duration and insomnia symptoms should be evaluated when assessing suicide risk.     

Gender differences in the association of insomnia symptoms and coronary artery calcification in the multi-ethnic study of atherosclerosis

Study ObjectivesTo quantify the gender-specific associations between insomnia symptoms and subclinical atherosclerosis, measured by coronary artery calcium (CAC) scores, which has strong predictive value for incident cardiovascular disease.MethodsWe analyzed data from 1,429 participants in the Multi-Ethnic Study of Atherosclerosis (MESA). Participants completed standardized questionnaires and underwent polysomnography (PSG) and 7-day actigraphy. Insomnia symptoms were defined as: self-reported trouble falling, staying or returning to sleep, early-morning awakenings, or hypnotic use, for ≥5 nights/week. MESA assessed CAC using computed tomography. We employed multivariable linear regression to model the probability of CAC >0 overall and to model the linear continuous effect among those with nonzero CAC.ResultsOur sample was a mean age of 68.1 ± 9.1 years, 53.9% female, and 36.2% white, 28.0% black, 24.2% Hispanic, and 11.5% Chinese-American. Insomnia symptoms were present in 49.7% of men and 47.2% of women. In multivariable-adjusted analyses, insomnia symptoms was associated with an 18% higher prevalence of CAC (PR 1.18, 95% CI 1.04, 1.33) among females, but no association was observed among males (PR 1.00, 95% CI 0.91, 1.08). There was no evidence that the association between insomnia symptoms and prevalence of CAC >0 differed by objective sleep duration status (by single-night PSG or multi-night actigraphy) in females or males.ConclusionsWe found that among women, insomnia symptoms were associated with an 18% higher prevalence of CAC compared to no insomnia. Insomnia symptoms were not associated with CAC prevalence in men. Additionally, there was no evidence that the association between insomnia symptoms and CAC score >0 differed by objective short sleep duration status.     

Longitudinal associations of sleep problems with alcohol and cannabis use from adolescence to emerging adulthood

Study ObjectivesThis study examined longitudinal associations of sleep problems with alcohol and cannabis use across six annual waves of data from adolescence to emerging adulthood.MethodsParticipants were 3,265 youth from California (ages 16–22 across waves). At each wave, past-month alcohol use and cannabis use, mental health, and several dimensions of sleep health (i.e. social jetlag, bedtimes, time in bed, trouble sleeping) were assessed via questionnaire. Parallel process latent growth models examined the association between sleep and alcohol or cannabis use trajectories and the role of mental health in contributing to such trajectories.ResultsSmaller declines in social jetlag (r = 0.11, p = 0.04), increases in trouble sleeping (r = 0.18, p < 0.01), and later weekday (r = 0.16, p < 0.01) and weekend bedtimes (r = 0.25, p < 0.01) were associated with increases in likelihood of alcohol use over time. Declines in weekend TIB (r = −0.13, p = 0.03), as well as increases in weekday TIB (r = 0.11, p = 0.04) and later weekday (r = 0.18, p < 0.01) and weekend bedtime (r = 0.24, p < 0.01), were associated with increases in likelihood of cannabis use over time. Most associations remained significant after controlling for time-varying mental health symptoms.ConclusionsTrajectories of sleep health were associated with trajectories of alcohol and cannabis use during late adolescence to emerging adulthood. Improving sleep is an important target for intervention efforts to reduce the risk of substance use during this critical developmental transition.     

Identifying and characterizing longitudinal patterns of insomnia across the deployment cycle in active duty Army soldiers

Study ObjectivesThe present study characterized a sample of 4,667 Army soldiers based on their patterns of insomnia before, during, and after deployment, and explored pre-deployment factors predictive of these patterns.MethodsData were analyzed from the Army Study to Assess Risk and Resilience in Service members (STARRS)—Pre/Post Deployment Study (PPDS), using surveys that captured data approximately 1–2 months pre-deployment, and 3- and 9-month post-deployment from soldiers deployed to Afghanistan. Patterns of insomnia across time were examined. Theoretically derived variables linked to sleep disturbance were examined as predictors of the insomnia patterns.ResultsFive longitudinal patterns of insomnia characterized the majority of the sample: “No Insomnia” (no insomnia symptoms at any timepoint; 31%), “Deployment-related Insomnia” (no pre-deployment insomnia, developed insomnia symptoms during deployment and recovered; 40%), “Incident Insomnia” (development insomnia during or shortly after deployment that did not remit; 14%), “Chronic Insomnia” (insomnia both pre- and post-deployment; 11%), and “Other Insomnia” (reported insomnia at ≥1 timepoint, but no clear pattern across the deployment cycle; 4%). Several pre-deployment factors were predictive of insomnia trajectories, including lifetime major depressive episodes, traumatic brain injury history, posttraumatic stress disorder, and past year personal life stressors.ConclusionsDistinct longitudinal patterns of insomnia were identified, with more than half of the sample reporting insomnia at some point in the deployment cycle. Identifying mental health conditions that are associated with different insomnia patterns prior to deployment can inform targeted interventions to reduce long-term sleep difficulty.     

Prevalent,incident, and persistent insomnia in a population-based cohort tested before (2018) and during the first-wave of COVID-19 pandemic (2020)

Study ObjectivesHigh rates of sleep and mental health problems have been reported during the COVID-19 pandemic, but most of the evidence is retrospective without pre-pandemic data. This study documented rates of prevalent, incident, and persistent insomnia and psychological symptoms during the COVID-19 pandemic (2020) compared to pre-pandemic data (2018).MethodsData were derived from a longitudinal, population-based study of insomnia in Canada. When the first lockdown started in the province of Quebec, a subsample of participants who had completed the latest 2018 follow-up were surveyed (April to May 2020) about their sleep, insomnia, and psychological symptoms since the beginning of the pandemic. Prevalence, incidence, and persistence rates of insomnia, and severity of stress, anxiety, and depressive symptoms were estimated, as well as their associations with confinement, loneliness, social support, use of electronics, and other lifestyle changes occurring during the pandemic. A sleep/health survey and validated questionnaires of insomnia, sleep quality, stress, fatigue, anxiety, and depression were administered at both assessments.ResultsThe sample consisted of 594 adults (mean age: 48.3 ± 13.1 years; 64.0% women). Prevalence of insomnia increased from 25.4% to 32.2% (symptoms) and from 16.8% to 19% (syndrome) from 2018 to 2020, for an overall 26.7% increase in insomnia rates. Of those classified as good sleepers in 2018 (n = 343), 32.6% (n = 112) had developed new insomnia during the COVID-19 pandemic. Among participants who had insomnia in 2018, the persistence rate was 76.5% 2 years later. There was a significant worsening of sleep quality, fatigue, anxiety, and depression (all ps < .005) during the COVID-19 pandemic compared to 2018. Significant associations were found between sleep and psychological symptoms and with living alone and being in confinement, lower social support, increased time using electronic devices, reduced physical exercise, and higher financial stress.ConclusionsThe COVID-19 pandemic is associated with significant increases in insomnia and psychological symptoms compared to the pre-pandemic period. Large scale public sleep and mental health intervention programs should be prioritized during and after a pandemic such as the COVID-19.     

Associations of insomnia symptoms with subsequent health services use among community-dwelling U.S. older adults

Study ObjectivesDetermine the association of insomnia symptoms with subsequent health services use, in a representative sample of U.S. older adults.MethodsParticipants were 4,289 community-dwelling Medicare beneficiaries who had continuous fee-for-service Medicare coverage 30 days before, and 1 year after the National Health and Aging Trends Study (NHATS) Round 1 interview. Participants reported past-month insomnia symptoms (i.e. sleep onset latency >30 min, difficulty returning to sleep) which we categorized as 0, 1, or 2 symptoms. Outcomes were health services use within 1 year of interviews from linked Medicare claims: emergency department (ED) visits, hospitalizations, 30-day readmissions, home health care (all measured as yes/no), and number of hospitalizations and ED visits.ResultsOverall, 18.5% of participants were hospitalized, 28.7% visited the ED, 2.5% had a 30-day readmission, and 11.3% used home health care. After adjustment for demographics, depressive and anxiety symptoms, medical comorbidities, and BMI, compared to participants with no insomnia symptoms, those with two insomnia symptoms had a higher odds of ED visits (odds ratio [OR) = 1.60, 95% confidence interval [CI] = 1.24–2.07, p < 0.001), hospitalizations (OR = 1.29, 95% CI = 1.01–1.65, p < 0.05), and 30-day readmissions (OR = 1.88, 95% CI = 1.88–3.29, p < 0.05). Reporting 2 insomnia symptoms, versus no insomnia symptoms, was associated with a greater number of ED visits and hospitalizations (incidence rate ratio (IRR) = 1.52, 95% CI = 1.23–1.87, p < 0.001; IRR = 1.21, 95% CI = 1.02–1.44, p < 0.05, respectively) after adjusting for demographic and health characteristics.ConclusionsAmong older adults, insomnia symptoms are associated with greater health services use, including emergency department use, hospitalization, and 30-day readmission. Targeting insomnia may lower health services use.     

Insomnia with objective short sleep duration is associated with cognitive impairment: a first look at cardiometabolic contributors to brain health

Study ObjectivesInsomnia with objective short sleep duration has been previously associated with adverse cardiometabolic health outcomes as well as poorer cognitive performance in otherwise noncognitively impaired adults. However, studies demonstrating an increased prevalence of cognitive impairment (CI) in this insomnia phenotype are lacking.MethodsWe analyzed data from Penn State Adult Cohort (N = 1,524; 48.9 ± 13.4 years; 53.4% women). Self-reported sleep difficulty was defined as normal sleep (n = 899), poor sleep (n = 453), and chronic insomnia (n = 172). Objective short sleep duration was defined as less than 6-h of sleep, based on in-lab, 8-h polysomnography. CI (n = 155) and possible vascular cognitive impairment (pVCI, n = 122) were ascertained using a comprehensive neuropsychological battery. Analyses adjusted for age, sex, race, education, body mass index, apnea/hypopnea index, smoking, alcohol, psychoactive medication, and mental and physical health problems.ResultsParticipants who reported poor sleep or chronic insomnia and slept objectively less than 6 hours were associated with a 2-fold increased odds of CI (OR = 2.06, 95% confidence limits [CL] = 1.15–3.66 and OR = 2.18, 95% CL = 1.07–4.47, respectively) and of pVCI (OR = 1.94, 95% CL = 1.01–3.75 and OR = 2.33, 95% CL = 1.07–5.06, respectively). Participants who reported poor sleep or chronic insomnia and slept objectively more than 6 hours were not associated with increased odds of either CI (OR = 0.72, 95% CL = 0.30–1.76 and OR = 0.75, 95% CL = 0.21–2.71, respectively) or pVCI (OR = 1.08, 95% CL = 0.42–2.74 and OR = 0.76, 95% CL = 0.16–3.57, respectively).ConclusionsInsomnia with objective short sleep duration is associated with an increased prevalence of CI, particularly as it relates to cardiometabolic health (i.e. pVCI). These data further support that this insomnia phenotype may be a more biologically severe form of the disorder associated with cardiovascular, cerebrovascular, and neurocognitive morbidity.     

The Mediating Effect of Insomnia on the Relationship between Panic Symptoms and Depression in Patients with Panic Disorder

BackgroundThis study aimed to determine if sleep disturbances may mediate the relationship between panic symptoms and depression in patients with panic disorder (PD).MethodsElectronic medical records were retrospectively reviewed for 110 consecutive patients with diagnosed PD in an outpatient clinic between October 2018 and December 2019. Measurements include the PD Severity Scale, Beck Depression Inventory-II (BDI-II) and Insomnia Severity Index (ISI). Statistical analyses were performed to assess any potential relationship between PD, insomnia and depression.ResultsOf the PD patients, 88 (80%) and 89 (80.9%) had comorbid depression (BDI-II ≥ 14) and insomnia (Korean version of the ISI ≥ 8), respectively. In a mediation model using insomnia as the mediating variable, the total effect of panic symptom severity on depression was significant (t = 7.23, P < 0.001). There were significant effects of panic symptoms on insomnia (t = 4.62, P < 0.001) and of insomnia on depression (t = 6.69, P < 0.001). The main effect of panic symptom severity on depression was also significant, after controlling for the effect of insomnia (t = 5.10, P < 0.001), suggesting partial mediation.ConclusionBoth depressive symptoms and insomnia are common in patients with PD and depression was partially mediated by insomnia in these patients. These results suggest that an intervention for insomnia in patients with PD might help prevent the development of depression.     

Treating insomnia symptoms with medicinal cannabis: a randomized,crossover trial of the efficacy of a cannabinoid medicine compared with placebo

Study ObjectivesThis randomized, double-blind, placebo-controlled, crossover study was conducted to evaluate the safety and efficacy of 2 weeks of nightly sublingual cannabinoid extract (ZTL-101) in treating chronic insomnia (symptoms ≥3 months).MethodsCo-primary study endpoints were safety of the medication based on adverse event reporting and global insomnia symptoms (Insomnia Severity Index [ISI]). Secondary endpoints included: self-reported (sleep diary), actigraphy-derived, and polysomnography measurements of sleep onset latency (SOL), wake after sleep onset (WASO), total sleep time (TST), sleep efficiency (SE); and self-reported assessments of sleep quality (sSQ) and feeling rested upon waking. Adjusted mean differences between placebo and ZTL-101 were calculated.ResultsTwenty-three of 24 randomized participants (n = 20 female, mean age 53 ± 9 years) completed the protocol. No serious adverse events were reported. Forty mild, nonserious, adverse events were reported (36 during ZTL-101) with all but one resolving overnight or soon after waking. Compared to placebo, ZTL-101 decreased ISI (−5.07 units [95% CI: −7.28 to −2.86]; p = 0.0001) and self-reported SOL (−8.45 min [95% CI: −16.33 to −0.57]; p = 0.04) and increased self-reported TST (64.6 min [95% CI: 41.70 to 87.46]; p < 0.0001), sSQ (0.74 units [95% CI: 0.51 to 0.97]; p < 0.0001), and feeling of being rested on waking (0.51 units [95% CI: 0.24 to 0.78]; p = 0.0007). ZTL-101 also decreased actigraphy-derived WASO (−10.2 min [95% CI: −16.2 to −4.2]; p = 0.002), and increased actigraphy-derived TST (33.4 min [95% CI: 23.07 to 43.76]; p < 0.001) and SE (2.9% [95% CI: 2.0 to 3.8]; p = 0.005).ConclusionsTwo weeks of nightly sublingual administration of a cannabinoid extract (ZTL-101) is well tolerated and improves insomnia symptoms and sleep quality in individuals with chronic insomnia symptoms.Clinical TrialANZCTR; anzctr.org.au; ACTRN12618000078257.     

Personality and insomnia symptoms in older adults: the Baltimore Longitudinal Study of Aging

Study ObjectiveTo examine associations of personality dimensions and facets with insomnia symptoms in a community sample of older adults.MethodsWe studied 1049 participants aged 60–97 years in the Baltimore Longitudinal Study of Aging. Personality was assessed by the Revised NEO Personality Inventory (NEO-PI-R), and insomnia symptom severity was measured by the Women’s Health Initiative Insomnia Rating Scale (WHIIRS).ResultsAdjusting for demographic characteristics, higher neuroticism, lower conscientiousness, and lower extraversion were associated with greater insomnia symptom severity. These associations remained significant for neuroticism and conscientiousness when further adjusting for depressive symptoms and comorbidities. Higher scores on neuroticism facets Anxiety, Angry Hostility, and Depression, and lower scores on conscientiousness facets Competence, Order, and Achievement Striving and on agreeableness facet Altruism were associated with greater insomnia symptom severity in fully adjusted models. Results were similar among cognitively normal older adults (N = 966), except higher scores on extraversion facets Warmth and Assertiveness associated with lower insomnia symptom severity, and agreeableness facet Altruism was unassociated.ConclusionAmong older adults, insomnia symptoms appear partially related to personality, with persons higher in neuroticism experiencing greater insomnia symptom severity, and those higher in conscientiousness experiencing lower insomnia symptom severity. Exploring facets of the Big-Five dimensions may provide additional insight regarding the etiology and resolution of sleep disturbance, and some of these associations may differ based on cognitive status. Future studies should investigate the hypothesis that sleep impairment mediates part of the association between specific personality traits and health-related outcomes.     

Insomnia with Objective Short Sleep Duration is Associated with Deficits in Neuropsychological Performance: A General Population Study

Study Objectives:

To examine the joint effect of insomnia and objective short sleep duration on neuropsychological performance.

Design:

Representative cross-sectional study.

Setting:

Sleep laboratory.

Participants:

1,741 men and women randomly selected from central Pennsylvania.

Interventions:

None.

Measurements:

Insomnia (n = 116) was defined by a complaint of insomnia with a duration ≥ 1 year and the absence of sleep disordered breathing (SDB), while normal sleep (n = 562) was defined as the absence of insomnia, excessive daytime sleepiness, and SDB. Both groups were split according to polysomnographic sleep duration into 2 categories: ≥ 6 h of sleep (“normal sleep duration”) and < 6 h of sleep (“short sleep duration”). We compared the groups'' performance on a comprehensive neuropsychological battery that measured processing speed, attention, visual memory, and verbal fluency, while controlling for age, race, gender, education, body mass index, and physical and mental health.

Results:

No significant differences were detected between insomniacs and controls. However, the insomnia with short sleep duration group compared to the control with normal or short sleep duration groups showed poorer neuropsychological performance in variables such as processing speed, set-switching attention, and number of visual memory errors and omissions. In contrast, the insomnia with normal sleep duration group showed no significant deficits.

Conclusions:

Insomnia with objective short sleep duration is associated with deficits in set-switching attentional abilities, a key component of the “executive control of attention.” These findings suggest that objective sleep duration may predict the severity of chronic insomnia, including its effect on neurocognitive function.

Citation:

Fernandez-Mendoza J; Calhoun S; Bixler EO; Pejovic S; Karataraki M; Liao D; Vela-Bueno A; Ramos-Platon MJ; Sauder KA; Vgontzas AN. Insomnia with objective short sleep duration is associated with deficits in neuropsychological performance: a general population study. SLEEP 2010;33(4):459-465.     

Patterns of concomitant prescription,over-the-counter and natural sleep aid use over a 12-month period: a population based study

Study ObjectivesConcomitant patterns of sleep aid use may provide insight for understanding the transition to chronic sleep medication use. Therefore, we sought to characterize the trajectories of concomitant natural product (NP), over-the-counter (OTC), and prescribed (Rx) sleep aid use in a population-based sample over 12-months.MethodsSelf-reported data on the use of NP, OTC, and Rx sleep aids were extracted from a Canadian longitudinal study on the natural history of insomnia (N = 3416, M age = 49.7 ± 14.7 years old; 62% women) at baseline, 6-month, and 12-month. Latent class growth modeling was used to identify latent class trajectories using MPlus Version 7. Participants completed a battery of clinical measures: Ford Insomnia Response to Stress Test, abbreviated Dysfunctional Beliefs and Attitudes about Sleep Scale, Beck Depression Inventory, Insomnia Severity Index and, the Pittsburgh Sleep Quality Index. Associations between class membership and baseline covariates were evaluated.ResultsConcurrent sleep aid use fell into six distinct latent class trajectories over a 12-month period: Minimal Use (74.5%), Rx-Dominant (11.3%), NP-Dominant (6.3%), OTC-Dominant (4.3%), Rx-NP-Dominant (2.4%), and Rx-OTC-Dominant (1.1%). The three latent classes with prominent prescribed agent use predicted greater incidence of healthcare professional consultations for their sleep (p < 0.05), poorer sleep quality (p < 0.001), elevated dysfunctional sleep beliefs (p < 0.001), and sleep reactivity (p < 0.001). Compared to the other four latent classes, clinical profiles of Rx-NP-dominant and Rx-OTC-dominant groups endorsed greater severity across measures.ConclusionsPatterns of sleep aid use may provide insight for identifying individuals who may be vulnerable to inappropriate self-medicating practices.     

Association between socioeconomic status and longitudinal sleep quality patterns mediated by depressive symptoms

Study ObjectivesWe aimed to examine whether associations between socioeconomic status (SES) and longitudinal sleep quality patterns are mediated by depressive symptoms.MethodsWe utilized data on 3347 participants in the Korean Genome and Epidemiology Study aged 40–69 years at baseline from 2001 to 2002 who were followed up for 16 years. A group-based modeling approach was used to identify sleep quality trajectories using the Pittsburgh Sleep Quality Index (years 2, 6, 8, 10, and 12). Educational attainment (college graduated or less), monthly household income (≥$2500 or less), and occupation (unemployed, manual labor, and professional labor) at baseline (year 0) were used for analyses. Depressive symptoms were assessed using Beck’s Depression Inventory at year 4. Associations between SES and sleep quality patterns were examined using a multinomial logistic regression model. The mediation effect of depressive symptoms was further examined using PROC CAUSALMED.ResultsWe identified five distinct sleep quality trajectories: “normal-stable” (n = 1697), “moderate-stable” (n = 1157), “poor-stable” (n = 320), “developing to poor” (n = 84), and “severely poor-stable” (n = 89). Overall, associations between SES levels and longitudinal sleep patterns were not apparent after full adjustment for sociodemographic and lifestyle factors measured at baseline. Depressive symptoms, however, tended to fully mediate associations between SES levels and sleep quality patterns (odds ratio range for indirect effects of depressive symptoms: for education, 1.05-1.17; for income, 1.05-1.15).ConclusionA significant mediating role for depressive symptoms between SES levels and longitudinal sleep quality warrants consideration among mental healthcare professionals.     

Associations of Sleep Duration and Screen Time with Incidence of Overweight in European Children: The IDEFICS/I.Family Cohort

IntroductionOver the past decades, children have been increasingly using screen devices, while at the same time their sleep duration has decreased. Both behaviors have been associated with excess weight, and it is possible they act as mutually reinforcing behaviors for weight gain. The aim of the study was to explore independent, prospective associations of screen time and sleep duration with incident overweight in a sample of European children.MethodsData from 4,285 children of the IDEFICS/I.Family cohort who were followed up from 2009/2010 to 2013/2014 were analyzed. Hours per day of screen time and of sleep duration were reported by parents at baseline. Logistic regression analyses were carried out in separate and mutually adjusted models controlled for sex, age, European country region, parental level of education, and baseline BMI z-scores.ResultsAmong normal weight children at baseline (N = 3,734), separate models suggest that every hour increase in screen time and every hour decrease in sleep duration were associated with higher odds of the child becoming overweight or obese at follow-up (OR = 1.16, 95% CI: 1.02–1.32 and OR = 1.23, 95% CI: 1.05–1.43, respectively). In the mutually adjusted model, both associations were attenuated slightly (screen time OR = 1.13, 95% CI: 0.99–1.28; sleep duration OR = 1.20, 95% CI: 1.03–1.40), being consistently somewhat stronger for sleep duration.Discussion/ConclusionBoth screen time and sleep duration increased the incidence of overweight or obesity by 13–20%. Interventions that include an emphasis on adequate sleep and minimal screen time are needed to establish their causal role in the prevention of overweight and obesity among European children.     

Characteristics and reproducibility of novel sleep EEG biomarkers and their variation with sleep apnea and insomnia in a large community-based cohort

Study ObjectivesNew electroencephalogram (EEG) features became available for use in polysomnography and have shown promise in early studies. They include a continuous index of sleep depth (odds-ratio-product: ORP), agreement between right and left sleep depth (R/L coefficient), dynamics of sleep recovery following arousals (ORP-9), general EEG amplification (EEG Power), alpha intrusion and arousal intensity. This study was undertaken to establish ranges and reproducibility of these features in subjects with different demographics and clinical status.MethodsWe utilized data from the two phases of the Sleep-Heart-Health-Study (SHHS1 and SHHS2). Polysomnograms of 5,804 subjects from SHHS1 were scored to determine the above features. Feature values were segregated according to clinical status of obstructive sleep apnea (OSA), insomnia, insomnia plus OSA, no clinical sleep disorder, and demographics (age, gender, and race). Results from SHHS visit2 were compared with SHHS1 results.ResultsAll features varied widely among clinical groups and demographics. Relative to participants with no sleep disorder, wake ORP was higher in participants reporting insomnia symptoms and lower in those with OSA (p < 0.0001 for both), reflecting opposite changes in sleep pressure, while NREM ORP was higher in both insomnia and OSA (p<0.0001), reflecting lighter sleep in both groups. There were significant associations with age, gender, and race. EEG Power, and REM ORP were highly reproducible across the two studies (ICC > 0.75).ConclusionsThe reported results serve as bases for interpreting studies that utilize novel sleep EEG biomarkers and identify characteristic EEG changes that vary with age, gender and may help distinguish insomnia from OSA.     

Suicidal ideation is associated with nighttime wakefulness in a community sample

Study ObjectivesNocturnal wakefulness is a risk factor for suicide and suicidal ideation in clinical populations. However, these results have not been demonstrated in general community samples or compared to sleep duration or sleep quality. The present study explored how the timing of wakefulness was associated with suicidal ideation for weekdays and weekends.MethodsData were collected from 888 adults aged 22–60 as part of the Sleep and Healthy Activity, Diet, Environment, and Socialization study. Suicidal ideation was measured by the Patient Health Questionnaire-9, while timing of wakefulness was estimated from the Sleep Timing Questionnaire. Binomial logistic regressions estimated the association between nocturnal (11 pm–5 am) and morning (5 am–11 am) wakefulness and suicidal ideation.ResultsNocturnal wakefulness was positively associated with suicidal ideation on weekdays (OR: 1.44 [1.28–1.64] per hour awake between 11:00 pm and 05:00 am, p < 0.0001) and weekends (OR: 1.22 [1.08–1.39], p = 0.0018). Morning wakefulness was negatively associated with suicidal ideation on weekdays (OR: 0.82 [0.72–0.92] per hour awake between 05:00 am and 11:00 am, p = 0.0008) and weekends (OR: 0.84 [0.75–0.94], p = 0.0035). These associations remained significant when adjusting for sociodemographic factors. Additionally, nocturnal wakefulness on weekdays was associated with suicidal ideation when accounting for insomnia, sleep duration, sleep quality, and chronotype (OR 1.25 [1.09–1.44] per hour awake, p = 0.002).ConclusionWakefulness at night was consistently associated with suicidal ideation. Additionally, morning wakefulness was negatively associated with suicidal ideation in some models. Although these findings are drawn from a non-clinical sample, larger longitudinal studies in the general population are needed to confirm these results.     

Sleep symptomatology is associated with greater subjective cognitive concerns: findings from the community-based Healthy Brain Project

Study ObjectivesTo examine if sleep symptomatology was associated with subjective cognitive concerns or objective cognitive performance in a dementia-free community-based sample.MethodsA total of 1,421 middle-aged participants (mean ± standard deviation = 57 ± 7; 77% female) from the Healthy Brain Project completed the Pittsburgh Sleep Quality Index, Insomnia Severity Index, and Epworth Sleepiness Scale to measure sleep quality, insomnia symptom severity, and daytime sleepiness, respectively. Participants were classified as having no sleep symptomatology (normal scores on each sleep measure), moderate sleep symptomatology (abnormal scores on one sleep measure), or high sleep symptomatology (abnormal scores on at least two sleep measures), using established cutoff values. Analysis of covariance was used to compare objective cognitive function (Cogstate Brief Battery) and subjective cognitive concerns (Modified Cognitive Function Instrument) across groups.ResultsFollowing adjustments for age, sex, education, mood, and vascular risk factors, persons classified as having high sleep symptomatology, versus none, displayed more subjective cognitive concerns (d = 0.24) but no differences in objective cognitive performance (d = 0.00–0.18). Subjective cognitive concerns modified the association between sleep symptomatology and psychomotor function. The strength of the relationship between high sleep symptomatology (versus none) and psychomotor function was significantly greater in persons with high as compared with low cognitive concerns (β ± SE = −0.37 ± 0.16; p = 0.02).ConclusionsMore severe sleep symptomatology was associated with greater subjective cognitive concerns. Persons reporting high levels of sleep symptomatology may be more likely to display poorer objective cognitive function in the presence of subjective cognitive concerns.     

Associations of loneliness and social isolation with actigraph and self-reported sleep quality in a national sample of older adults

Study ObjectivesTo examine associations of social isolation and loneliness with sleep in older adults and whether associations differ for survey and actigraph sleep measures.MethodsThis study used data from the National Social Life, Health, and Aging Project (NSHAP), a nationally representative study of community-dwelling older adults born 1920–1947. A random one-third of participants in 2010–2011 were invited to participate in a sleep study (N = 759) that included survey questions, 72 hours of wrist actigraphy, and a sleep log. Perceived loneliness was measured using three questions from the UCLA Loneliness Scale. An index of social isolation was constructed from nine items that queried social network characteristics and social interactions. We used ordinary least squares and ordinal logistic regression to examine whether sleep measures were associated with loneliness and social isolation adjusted for potential sociodemographic confounders.ResultsSocial isolation and loneliness had a low correlation (Spearman’s correlation = 0.20). Both loneliness and social isolation were associated with actigraphy measures of more disrupted sleep: wake after sleep onset and percent sleep. Neither was associated with actigraph total sleep time. Increased loneliness was strongly associated with more insomnia symptoms and with shorter sleep duration assessed by a single question, but social isolation was not. More isolated individuals spent a longer time in bed.ConclusionsWe found that both loneliness and social isolation were associated with worse actigraph sleep quality, but their associations with self-reported sleep differed. Only loneliness was associated with worse and shorter self-reported sleep.     

Intraindividual variability in sleep schedule: effects of an internet-based cognitive-behavioral therapy for insomnia program and its relation with symptom remission

Study ObjectivesSleep schedule consistency is fundamental to cognitive-behavioral therapy for insomnia (CBT-I), although there is limited evidence suggesting whether it predicts treatment response. This analysis tested whether: (1) an Internet-based CBT-I program affects intraindividual variability (IIV) in sleep schedule and (2) sleep schedule IIV predicts insomnia symptom remission.MethodsThis secondary analysis compares participants (N = 303) randomized to an Internet-based CBT-I program (SHUTi—Sleep Healthy Using the Internet) or Internet-based patient education (PE). Participants reported daily bedtimes and rising times on 10 online sleep diaries collected over 2 weeks at baseline and 9-week post-intervention assessment. Participants completed the Insomnia Severity Index (ISI) at post-assessment and 6-month follow-up; symptom remission was defined by ISI < 8. Mixed effects location scale modeling was used to examine the effect of SHUTi on bedtime and rising time IIV; a novel two-staged analysis examined the effect of bedtime and rising time IIV on insomnia symptom remission.ResultsAt post-assessment, SHUTi participants reported about 30% less bedtime and 32% less rising time variability compared to PE (ps < 0.03). Bedtime and rising time IIV was not independently associated with likelihood of insomnia symptom remission at the subsequent time point (ps > 0.18), nor did sleep schedule IIV moderate treatment response (ps > 0.12).ConclusionsFindings demonstrate that an Internet-delivered CBT-I program can effectively increase users’ sleep schedule consistency relative to an educational control. This consistency, however, was not related to treatment outcome when defined by insomnia symptom remission, suggesting that enforcing rigid sleep schedules for patients may not be necessary for treatment success.Clinical Trial Registration{"type":"clinical-trial","attrs":{"text":"NCT00328250","term_id":"NCT00328250"}}NCT00328250     

The effect of sleep–wake intraindividual variability in digital cognitive behavioral therapy for insomnia: a mediation analysis of a large-scale RCT

Study ObjectivesDigital cognitive behavioral therapy for insomnia (dCBT-I) is an effective treatment for insomnia. However, less is known about mediators of its benefits. The aim of the present study was to test if intraindividual variability in sleep (IIV) was reduced with dCBT-I, and whether any identified reduction was a mediator of dCBT-I on insomnia severity and psychological distress.MethodsIn a two-arm randomized controlled trial (RCT), 1720 adults with insomnia (dCBT-I = 867; patient education about sleep = 853) completed the Insomnia Severity Index (ISI), the Hospital Anxiety and Depression Scale (HADS) and sleep diaries, at baseline and 9-week follow-up. Changes in IIV were analyzed using linear mixed modeling followed by mediation analyses of ISI, HADS, and IIV in singular sleep metrics and composite measures (behavioral indices (BI-Z) and sleep disturbance indices (SI-Z)).ResultsdCBT-I was associated with reduced IIV across all singular sleep metrics, with the largest between-group effect sizes observed for sleep onset latency (SOL). Reduced IIV for SOL and wake after sleep onset had the overall greatest singular mediating effect. For composite measures, SI-Z mediated change in ISI (b = −0.74; 95% confidence interval (CI) −1.04 to −0.52; 13.3%) and HADS (b = −0.40; 95% CI −0.73 to −0.18; 29.2%), while BI-Z mediated minor changes.ConclusionReductions in IIV in key sleep metrics mediate significant changes in insomnia severity and especially psychological distress when using dCBT-I. These findings offer important evidence regarding the therapeutic action of dCBT-I and may guide the future development of this intervention.Clinical trials Name: Overcoming Insomnia: Impact on Sleep, Health and Work of Online CBT-I Registration number: NCT02558647 URL: https://clinicaltrials.gov/ct2/show/NCT02558647?cond=NCT02558647&draw=2&rank=1