Objective

Depression is often associated with disruptions in sleep and circadian rhythms. We aimed to confirm these relationships via actigraphic assessment in a large, population-based sample and test whether sex moderates these relationships.

Methods

A total of 418 participants (age = 35-85 years, mean [standard deviation] = 57.04 [11.47]) completed questionnaires and 1 week of actigraphy, used to calculate sleep and rest-activity statistics including mesor (mean activity level), amplitude (height of rhythm), and acrophase (time of day that rhythm peaks).

Results

Depressive symptoms, assessed via Center for Epidemiologic Studies Depression Scale, were associated with disrupted sleep and rest-activity rhythms. Furthermore, men demonstrated longer sleep onset latency (SOL, B = -13.28, p < .001), longer wake time after sleep onset (B = -6.26, p < .01), lower sleep efficiency (B = 5.91, p < .001), and lower total sleep time (TST, B = 33.16, p < .001) than women. Sex moderated the relationship between depression and SOL, TST, mesor, and amplitude; sex-stratified models revealed that higher depression scores were associated with greater SOL (B = 1.05, p < .001) and less TST (B = -0.87, p < .10) for women with higher depressive symptoms, but lower mesor (B = -1.75, p < .01) and amplitude (B = -1.94, p < .01) for men with higher depressive symptoms.

Conclusions

Depressive symptoms were related to disrupted sleep continuity and rest-activity rhythms in this population-based sample; however, these relationships differed by sex. Women with greater depressive symptoms exhibited difficulty with sleep continuity, whereas men with greater depressive symptoms demonstrated disruption throughout the 24-hour rhythm.

Study objectives

Depression has been identified as the most common condition comorbid to insomnia, with findings pointing to the possibility that these disorders may be causally related to each other or may share common mechanisms. Some have suggested that comorbid insomnia and depression may have a different clinical course than either condition alone, and may thus require specific treatment procedures. In this report we examined the clinical characteristics of individuals referred to an academic sleep center who report comorbid symptoms of insomnia and depression and those with symptoms of insomnia outside the context of meaningful depression, and we identified differences between these groups with regard to several cognitive-related variables.

Methods

Logistic regression analyses examined whether past week worry, dysfunctional beliefs about sleep, and insomnia symptom-focused rumination predicted group membership.

Results

Individuals with comorbid symptoms of insomnia and depression reported more past-week worry, dysfunctional beliefs about sleep, and insomnia symptom-focused rumination, than those with symptoms of insomnia without significant depression symptoms. When including all three cognitive-related variables in our model, those with comorbid symptoms reported more severe insomnia symptom-focused rumination, even when controlling for insomnia and mental health severity, among other relevant covariates.

Conclusion

The findings contribute to our understanding of the complex nature of comorbid symptoms of insomnia and depression and the specific symptom burden experienced by those with significant depression symptoms in the presence of insomnia. The findings also highlight the need for increased clinical attention to the sleep-focused rumination reported by these patients.

Study objectives

To examine nonrapid eye movement (NREM) sleep in insomnia using high-density electroencephalography (EEG).

Methods

All-night sleep recordings with 256 channel high-density EEG were analyzed for 8 insomnia subjects (5 females) and 8 sex and age-matched controls without sleep complaints. Spectral analyses were conducted using unpaired t-tests and topographical differences between groups were assessed using statistical non-parametric mapping. Five minute segments of deep NREM sleep were further analyzed using sLORETA cortical source imaging.

Results

The initial topographic analysis of all-night NREM sleep EEG revealed that insomnia subjects had more high-frequency EEG activity (> 16 Hz) compared to good sleeping controls and that the difference between groups was widespread across the scalp. In addition, the analysis also showed that there was a more circumscribed difference in theta (4-8 Hz) and alpha (8-12 Hz) power bands between groups. When deep NREM sleep (N3) was examined separately, the high-frequency difference between groups diminished, whereas the higher regional alpha activity in insomnia subjects persisted. Source imaging analysis demonstrated that sensory and sensorimotor cortical areas consistently exhibited elevated levels of alpha activity during deep NREM sleep in insomnia subjects relative to good sleeping controls.

Conclusions

These results suggest that even during the deepest stage of sleep, sensory and sensorimotor areas in insomnia subjects may still be relatively active compared to control subjects and to the rest of the sleeping brain.

Background

Epidemiological data have demonstrated seasonal and circadian patterns of suicidal deaths. Several reviews and meta-analyses have confirmed the relationship between sleep disturbance and suicidality. However, these reviews/meta-analyses have not focused on seasonal and circadian dysfunction in relation to suicidality, despite the common presence of this dysfunction in patients with mood disorders. Thus, the current literature review analyzed studies investigating person-specific chronotype, seasonality, and rhythmicity in relation to suicidal thoughts and behaviors.

Methods

Study authors reviewed articles related to individual-level chronotype, seasonality, and rhythmicity and suicidality that were written in English and not case reports or reviews.

Results

This review supports a relationship between an eveningness chronotype, greater seasonality, and decreased rhythmicity with suicidal thoughts and behaviors in those with unipolar depression, as well as in other psychiatric disorders and in children/adolescents.

Limitations

These findings need to be explored more fully in mood disordered populations and other psychiatric populations, in both adults and children, with objective measurement such as actigraphy, and with chronotype, seasonality, and rhythmicity as well as broader sleep disturbance measurement all included so the construct(s) most strongly linked to suicidality can be best identified.

Conclusions

Eveningness, greater seasonality, and less rhythmicity should be considered in individuals who may be at risk for suicidal thoughts and behaviors and may be helpful in further tailoring assessment and treatment to improve patient outcome.

Objective

To investigate (1) circadian rest-activity rhythm disturbances among endometrial cancer patients as they recover from surgery in comparison to a historical reference group of women with no cancer history and (2) health- and treatment-related predictors of dysregulated rest-activity rhythms in endometrial cancer patients.

Methods

60 endometrial cancer patients participated in a prospective, longitudinal study with actigraphic assessment at 1week, 1month, and 4months post-surgery. 60 women without cancer from an epidemiological sample completed one actigraphic assessment, acting as a reference group.

Results

On average, results revealed initial significant rest-activity dysregulation at 1week and 1month post-surgery for the endometrial cancer group and then significant recovery in rest-activity patterns at 4months post-surgery. Similarly, the cancer group had significantly more impaired rhythms than the reference group at 1week post-surgery, but demonstrated comparable rhythms by 4months post-surgery. Among the health- and treatment-related variables examined, obesity and receipt of more invasive surgery were found to predict more impaired rhythms at all time points.

Conclusion(s)

The current study highlights significant disturbances in rest-activity patterns for endometrial cancer patients initially during surgical recovery followed by improvement in these patterns by 4months post-surgery; however, obese patients and those having more invasive surgery demonstrated more impaired rest-activity patterns throughout the 4-month recovery period. Further research is warranted to understand how more impaired rest-activity patterns relate to health and quality of life outcomes.

In this paper, we report the rate of previously undiagnosed obstructive sleep apnea (OSA) in a randomized clinical trial (RCT) of suicidal patients with major depressive disorder (MDD). One hundred and twenty-five suicidal adults with MDD were recruited into a RCT. None were suspected to have OSA. Fourteen percent met diagnostic criteria for OSA. The Apnea Hypopnea Index (AHI) was predicted by increasing age, male sex, and higher Body Mass Index. However, neither the degree of daytime sleepiness nor the degree of insomnia predicted AHI severity. A high degree of suspicion is warranted for OSA in suicidal patients with MDD, and for patients with treatment-resistant depression. ClinicalTrials.gov identifier: NCT01689909.

Study objectives

Sleep disturbance is significantly associated with suicidal ideation. However, the majority of past research has examined the relationship between insomnia and suicidality. The current exploratory study examined the relationship of circadian rhythm dysregulation (eveningness, seasonality, and rhythmicity) with suicidality.

Methods

We examined the association of insomnia, eveningness, seasonality, and rhythmicity with suicidal ideation in 103 participants with depression, insomnia, and suicidality within a larger 8-week double-blinded randomized control trial primarily examining whether cautious use of zolpidem extended-release or placebo reduced suicidal ideation. All participants additionally received an open-label selective serotonin reuptake inhibitor. Methodological strengths of the current analyses included consideration of multiple sleep-wake constructs, adjustment for relevant covariates, investigation of relationships over the course of treatment, and use of both self-report measures and objective measurement with actigraphy.

Results

Over the course of treatment, self-reported eveningness and greater insomnia severity were independently correlated with greater suicidal ideation, whereas actigraphic delayed sleep timing was related to suicidal ideation at a trend level. At the end of treatment, those with greater suicidal ideation demonstrated lower actigraphic activity levels. There were no significant relationships between self-reported seasonality and actigraphic measures of sleep disturbance and suicidality.

Conclusions

Self-reported delays in sleep timing, objectively lower activity levels, and self-reported insomnia severity correlated independently with greater suicidal ideation in those with depression, insomnia, and suicidality. These exploratory findings highlight the need to consider sleep-wake constructs more broadly in those with suicidality in future research studies in order to improve more definitively both assessment and intervention efforts.

Clinical trial registration

Registry: ClinicalTrials.gov; Name: Reducing Suicidal Ideation through Insomnia Treatment; URL: https://clinicaltrials.gov/ct2/show/NCT01689909; Identifier: NCT01689909 Rumble ME, McCall MV, Dickson DA, Krystal AD, Rosenquist PB, Benca RM. An exploratory analysis of the association of circadian rhythm dysregulation and insomnia with suicidal ideation over the course of treatment in individuals with depression, insomnia, and suicidal ideation. J Clin Sleep Med. 2020;16(8):XXX-XXX.

Objective

Changes in slow waves during non-rapid eye movement (NREM) sleep in response to acute total sleep deprivation are well-established measures of sleep homeostasis. This investigation utilized high-density electroencephalography (hdEEG) to examine topographic changes in slow waves during repeated partial sleep deprivation.

Methods

Twenty-four participants underwent a 6-day sleep restriction protocol. Spectral and period-amplitude analyses of sleep hdEEG data were used to examine changes in slow wave energy, count, amplitude, and slope relative to baseline.

Results

Changes in slow wave energy were dependent on the quantity of NREM sleep utilized for analysis, with widespread increases during sleep restriction and recovery when comparing data from the first portion of the sleep period, but restricted to recovery sleep if the entire sleep episode was considered. Period-amplitude analysis was less dependent on the quantity of NREM sleep utilized, and demonstrated topographic changes in the count, amplitude, and distribution of slow waves, with frontal increases in slow wave amplitude, numbers of high-amplitude waves, and amplitude/slopes of low amplitude waves resulting from partial sleep deprivation.

Conclusions

Topographic changes in slow waves occur across the course of partial sleep restriction and recovery.

Significance

These results demonstrate a homeostatic response to partial sleep loss in humans.

Objective

The authors sought to determine whether targeted treatment of insomnia with controlled-release zolpidem (zolpidem-CR) in suicidal adults with insomnia would provide a reduction in suicidal ideation superior to placebo.

Methods

Reducing Suicidal Ideation Through Insomnia Treatment was an 8-week three-site double-blind placebo-controlled parallel-group randomized controlled trial of zolpidem-CR hypnotic therapy compared with placebo, in conjunction with an open-label selective serotonin reuptake inhibitor. Participants were medication-free 18- to 65-year-olds with major depressive disorder, insomnia, and suicidal ideation. Suicidal ideation was the main outcome, measured first by the Scale for Suicide Ideation and second by the Columbia-Suicide Severity Rating Scale (C-SSRS).

Results

A total of 103 participants were randomly assigned to receive zolpidem-CR (N=51) or placebo (N=52) (64 women and 39 men; mean age=40.5 years). Zolpidem-CR had a robust anti-insomnia effect, especially in patients with the most severe insomnia symptoms. No significant treatment effect was observed on the Scale for Suicide Ideation (least squares mean estimate=-0.56, SE=0.83, 95% CI=-2.19, 1.08), but the reduction in scores was significantly positively related to improvement in insomnia after accounting for the effect of other depression symptoms. The C-SSRS indicated that zolpidem-CR had a significant treatment effect (least squares mean estimate=-0.26, SE=0.12, 95% CI=-0.50, -0.02). The advantage for zolpidem-CR in reducing suicidal ideation on the C-SSRS was greater in patients with more severe insomnia. No deaths or suicide attempts occurred.

Conclusions

Although the results do not support the routine prescription of hypnotic medication for mitigating suicidal ideation in all depressed outpatients with insomnia, they suggest that coprescription of a hypnotic during initiation of an antidepressant may be beneficial in suicidal outpatients, especially in patients with severe insomnia.