Objectives
The discovery of the blue lightsensitive retinal photoreceptor responsible for signaling daytime to the brain suggested that light to the circadian system could be inhibited by using ...blue‐blocking orange tinted glasses. Blue‐blocking (BB) glasses are a potential treatment option for bipolar mania. We examined the effectiveness of BB glasses in hospitalized patients with bipolar disorder in a manic state.
Methods
In a single‐blinded, randomized, placebo‐controlled trial (RCT), eligible patients (with bipolar mania; age 18–70 years) were recruited from five clinics in Norway. Patients were assigned to BB glasses or placebo (clear glasses) from 6 p.m. to 8 a.m. for 7 days, in addition to treatment as usual. Symptoms were assessed daily by use of the Young Mania Rating Scale (YMRS). Motor activity was assessed by actigraphy, and compared to data from a healthy control group. Wearing glasses for one evening/night qualified for inclusion in the intention‐to‐treat analysis.
Results
From February 2012 to February 2015, 32 patients were enrolled. Eight patients dropped out and one was excluded, resulting in 12 patients in the BB group and 11 patients in the placebo group. The mean decline in YMRS score was 14.1 95% confidence interval (CI): 9.7–18.5 in the BB group, and 1.7 (95% CI: −4.0 to 7.4) in the placebo group, yielding an effect size of 1.86 (Cohen's d). In the BB group, one patient reported headache and two patients experienced easily reversible depressive symptoms.
Conclusions
This RCT shows that BB glasses are effective and feasible as add‐on treatment for bipolar mania.
Use of blue-enriched light has received increasing interest regarding its activating and performance sustaining effects. However, studies assessing effects of such light during night work are few, ...and novel strategies for lighting using light emitting diode (LED) technology need to be researched. In a counterbalanced crossover design, we investigated the effects of a standard polychromatic blue-enriched white light (7000 K; ∼200 lx) compared to a warm white light (2500 K), of similar photon density (∼1.6 × 10
photons/cm
/s), during three consecutive simulated night shifts. A total of 30 healthy participants 10 males, mean age 23.3 (
= 2.9) years were included in the study. Dependent variables comprised subjective alertness using the Karolinska Sleepiness Scale, a psychomotor vigilance task (PVT) and a digit symbol substitution test (DSST), all administered at five time points throughout each night shift. We also assessed dim-light melatonin onset (DLMO) before and after the night shifts, as well as participants' opinion of the light conditions. Subjective alertness and performance on the PVT and DSST deteriorated during the night shifts, but 7000 K light was more beneficial for performance, mainly in terms of fewer errors on the PVT, at the end of the first- and second- night shift, compared to 2500 K light. Blue-enriched light only had a minor impact on PVT response times (RTs), as only the fastest 10% of the RTs were significantly improved in 7000 K compared to 2500 K light. In both 7000 and 2500 K light, the DLMO was delayed in those participants with valid assessment of this parameter
= 20 (69.0%) in 7000 K light,
= 22 (78.6%) in 2500 K light, with a mean of 2:34 (
= 0:14) and 2:12 (
= 0:14) hours, respectively, which was not significantly different between the light conditions. Both light conditions were positively rated, although participants found 7000 K to be more suitable for work yet evaluated 2500 K light as more pleasant. The data indicate minor, but beneficial, effects of 7000 K light compared to 2500 K light on performance during night work. Circadian adaptation did not differ significantly between light conditions, though caution should be taken when interpreting these findings due to missing data. Field studies are needed to investigate similar light interventions in real-life settings, to develop recommendations regarding illumination for night workers.
www.ClinicalTrials.gov, identifier NCT03203538.
To validate automatic sleep stage classification using deep neural networks on sleep assessed by radar technology in the commercially available sleep assistant Somnofy® against polysomnography (PSG).
...Seventy-one nights of overnight sleep in healthy individuals were assessed by both PSG and Somnofy at two different institutions. The Somnofy unit was placed in two different locations per room (nightstand and wall). The sleep algorithm was validated against PSG using a 25-fold cross validation technique, and performance was compared to the inter-rater reliability between the PSG sleep scored by two independent sleep specialists.
Epoch-by-epoch analyses showed a sensitivity (accuracy to detect sleep) and specificity (accuracy to detect wake) for Somnofy of 0.97 and 0.72 respectively, compared to 0.99 and 0.85 for the PSG scorers. The sleep stage differentiation for Somnofy was 0.75 for N1/N2, 0.74 for N3 and 0.78 for R, whilst PSG scorers ranged between 0.83 and 0.96. The intraclass correlation coefficient revealed excellent and good reliability for total sleep time and sleep efficiency, while sleep onset and R latency had poor agreement. Somnofy underestimated total wake time by 5 min and N1/N2 by 3 min. N3 was overestimated by 4 min and R by 3 min. Results were independent of institution and sensor location.
Somnofy showed a high accuracy staging sleep in healthy individuals and has potential to assess sleep quality and quantity in a sample of healthy, mostly young adults. More research is needed to examine performance in children, older individuals and those with sleep disorders.
•Radar technology/machine learning (Somnofy®) were validated against polysomnography.•In healthy adults, Somnofy® detected sleep/wake correctly 0.97 and 0.72 of the time.•Sleep stage differentiation showed substantial agreement with polysomnography.•TST and SE exhibited excellent and good reliability compared to polysomnography.
Background: Childhood sexual abuse (CSA) is a well-established risk factor for non-suicidal self-injury (NSSI) and suicide attempts (SA); still few studies have examined predictors of individual ...differences in NSSI/SA amongst CSA survivors.
Objective: To examine predictors of NSSI and SA among adult CSA-survivors.
Methods: In a sample of 516, primarily female adult CSA-survivors recruited from support centres for sexual abuse survivors in Norway, we examined the role of abuse/perpetrator characteristics, and the degree/severity of exposure to other types of childhood maltreatment (cumulative childhood maltreatment; CCM), as predictors of lifetime NSSI and SA. In a subsample of 138 individuals responding to follow-up waves two- and four years later, these same distal factors, as well as previous NSSI and proximal factors in the form of symptoms of mental health disorders (posttraumatic stress, anxiety, depression, sleep disturbances, and eating disorders), relational problems, and perceived social support, were examined as predictors of persistent NSSI. Finally, those attempting new SA during the follow-up period were compared to those who did not on these variables.
Results: Higher CCM scores and having had an unknown perpetrator positively predicted lifetime NSSI scores. Higher CCM scores, violent abuse, and having had an unknown perpetrator predicted lifetime SA. Higher CCM scores, previous NSSI, having had a known perpetrator, as well as higher depression-, anxiety- and eating disorder scores, positively predicted persistent NSSI during the four-year follow-up period. Compared to those with no new SA, those reporting new SA during the follow-up period had higher CCM, lifetime NSSI, mental health symptoms and relational problem scores, lower perceived social support scores, and were more likely to have done a past SA and to have experienced abuse involving physical violence.
Conclusions: A broad range of both distal and proximal factors should be assessed as potential predictors of NSSI and SA among adult CSA-survivors.
Objectives Shift-related sleep and sleepiness problems may be due to characteristics of both shifts (ie, day, evening and night shifts) and work schedules (ie, permanent vs rotational schedules). The ...Bergen Shift Work Sleep Questionnaire (BSWSQ) was used to investigate associations between shift-related sleep problems and work schedules. Methods 1586 nurses completed the BSWSQ. Participants who, in relation to a shift, ‘often’ or ‘always’ experienced both a sleep problem and a tiredness/sleepiness problem were defined as having shift-related insomnia (separate for day, evening and night shifts and rest-days). Logistic regression analyses were conducted for day, evening, night, and rest-day insomnia with participants on both permanent and rotational schedules. Results Shift-related insomnia differed between the work schedules. The evening shift insomnia was more prevalent in the two-shift rotation schedule than the three-shift rotation schedule (29.8% and 19.8%, respectively). Night shift insomnia showed higher frequencies among three-shift rotation workers compared with permanent night workers (67.7% and 41.7%, respectively). Rest-day insomnia was more prevalent among permanent night workers compared with two- and three-shift rotations (11.4% compared with 4.2% and 3.6%, respectively). Conclusions The prevalences of shift-related insomnia differed between the work schedules with higher frequencies for three-shift rotations and night shifts. However, sleep problems were present in all shifts and schedules. This suggests that both shifts and work schedules should be considered in the study of shift work-related sleep problems.
One of the most established hypotheses of depression focuses on alteration of the serotonergic (5-HT) function. Recent evidence suggests that serotonergic involvement in depression may be modulated ...by the action of gamma-hydroxybutyric acid (GABA). Furthermore, altered GABAergic function is also evident in depressed patients and in animal models of depression. Disturbed sleep is characteristic of patients with mood disorders. The most pronounced changes of the 5-HT firing activity occur during sleep. Hence, the present paper reports a study on simultaneously measurement of hippocampal levels of serotonin and GABA during waking and sleep in the chronic mild stress (CMS) animal model of depression. The neurotransmitter findings are accompanied by depression-like symptoms (e.g. sleep alterations and reduced sucrose intake, a putative indicator of anhedonia in rodents). Our results show that animals exposed to CMS had lower hippocampal GABA levels compared to controls. In addition, after CMS there was a lack of 5-HT stage-dependency. A subgroup (five out of eight animals) showed a consistent increase in 5-HT levels in slow wave sleep and REM sleep. We also observed that this increase occurred in those animals regarded as most anhedonic (lowest intake of sucrose solution). Moreover, REM sleep was positively correlated with anhedonia. No interaction between 5-HT and GABA was found in the hippocampus. The data suggest that both GABAergic and serotonergic systems may be simultaneously but independently involved in depression. The alteration in 5-HT function may represent a link between depression-like behaviour and sleep abnormalities found in depressed patients.
In pregnancy melatonin regulates circadian rhythms, induce sleep, and has a neuroprotective positive effect on fetal development. Artificial blue light in the evening delays and suppresses melatonin ...production. Thus, we investigated the effect of blocking blue light on the melatonin profile.
A randomized controlled trial (n=30 blue-blocking glasses vs. n=30 control glasses with partial blue-blocking effect) including healthy nulliparous pregnant women in the beginning of the third trimester. Salivary melatonin and subjective sleep were measured before and after two weeks of intervention/control condition. Saliva was sampled at 30-min intervals from 3 h before normal bedtime. Melatonin onset was set at 4.0 pg/ml.
Due to missing data melatonin onset was estimated for 47 participants. At posttreatment, melatonin onset advanced by 28 min in the blue-blocking group compared with the control condition (p=.019). Melatonin levels were significantly higher, favoring the blue-blocking glass condition, at clock time 20:00, 21:00 and 22:00 h, and for sample number 3 and 4. The phase angle (time interval) between melatonin onset and sleep bedtime and sleep onset time increased within the blue blocking group (+45 min and +41 min, respectively), but did not reach statistical significance compared to control condition (+13 min and +26 min, respectively).
Blocking blue light in the evening had a positive effect on the circadian system with an earlier onset and rise of melatonin levels in healthy nulliparous pregnant women. This demonstrated the effectiveness and feasibility of a simple non-pharmacological chronobiological intervention during pregnancy.
•BB-glasses advanced melatonin onset in pregnant women in the third trimester.•Blocking blue light seems to increase evening melatonin levels in pregnancy.•BB-glasses may be a treatment to improve circadian function of the pregnant women.
Few studies have investigated hallucinations that occur at the onset/offset of sleep (called hypnagogic/hypnopompic hallucinations; HHHs), despite the fact that their prevalence in the general ...population is reported to be higher than the prevalence of daytime hallucinations. We utilized data from an epidemiological study to explore the prevalence of HHHs in various modalities. We also investigated phenomenological differences between sleep-related (HHHs) and daytime hallucinations in the auditory modality. We hypothesized that individuals with only HHHs would not differ from controls on a range of mental health and wellbeing measures, but that if they occur together with daytime hallucinations will pose a greater burden on the individual experiencing them. We also hypothesize that HHHs are qualitatively different (i.e. less severe) from daytime hallucinations.
This study utilized data from a cross-sectional epidemiological study on the prevalence of hallucinations in the Norwegian general population. The sample (n = 2533) was divided into a control group without hallucinations (n = 2303), a group only experiencing sleep-related hallucinations (n = 62), a group only experiencing daytime hallucinations (n = 57), and a group experiencing both sleep-related as well as daytime hallucinations (n = 111). Prevalence rates were calculated and groups were compared using analyses of variance and chi-square tests where applicable.
The prevalence for HHHs in the auditory domain was found to be 6.8%, whereas 12.3% reported multimodal HHHs, and 32.2% indicated out-of-body experiences at the onset/offset of sleep. Group comparisons of hallucinations in the auditory modality showed that individuals that experienced only auditory HHHs scored significantly (p < 0.05) lower than those who also experienced daytime auditory hallucinations on a range of variables including mental health, anxiety, childhood happiness, and wellbeing. In addition, individuals with only auditory HHHs reported significantly (p < 0.05) less frequent hallucinations, less disturbing hallucinations, more neutral (in terms of content) hallucinations, hallucinations with less influence over their behavior, and less hallucination-related interference with social life compared to those individuals that experience daytime hallucinations. We also found that purely auditory HHHs had a significantly higher age of first onset of hallucinations than the purely daytime and the combined daytime and auditory HHHs groups (28.2 years>20.9 > 19.1).
Sleep-related hallucinations are common experiences in the general population, with the auditory modality being the least common. They occur mostly in combination with daytime hallucinations. However, some individuals (2.4%) experience only (auditory) sleep-related hallucinations and this group can be seen as more closely related, on a range of health-related factors, to non-hallucinating individuals than individuals who experience daytime hallucinations. Finally, there is a clear need for more research in this field, and ideas for future studies are presented.
•Sleep-related hallucinations are a common phenomenon in the general population and occur in several modalities.•Isolated sleep-related hallucinations are less severe than when they co-occur with daytime hallucinations.•Isolated sleep-related hallucinations have a later (in life) first-onset than daytime hallucinations.•Isolated sleep-related hallucinations may be attributed to different underlying mechanisms than daytime hallucinations.
Highlights • Use of an iPad in bed before turning the light off decreases subjective sleepiness. • Latency to sleep onset and time in different sleep stages was similar in the two reading conditions. ...• 30 min of reading a story on an iPad before bedtime delays EEG dynamics of slow-wave activity. • Even at low illumination level (58 lux), blue-enriched light from a tablet can impact directly on sleep EEG activity. • The use of electronic devices before bedtime may affect alertness, circadian physiology and sleep.
Night-shift work is linked to a shift in food intake toward the normal sleeping period, and to metabolic disturbance. We applied a rat model of night-shift work to assess the immediate effects of ...such a shift in food intake on metabolism. Male Wistar rats were subjected to 8 h of forced activity during their rest (ZT2-10) or active (ZT14-22) phase. Food intake, body weight, and body temperature were monitored across four work days and eight recovery days. Food intake gradually shifted toward rest-work hours, stabilizing on work day three. A subgroup of animals was euthanized after the third work session for analysis of metabolic gene expression in the liver by real-time polymerase chain reaction (PCR). Results show that work in the rest phase shifted food intake to rest-work hours. Moreover, liver genes related to energy storage and insulin metabolism were upregulated, and genes related to energy breakdown were downregulated compared to non-working time-matched controls. Both working groups lost weight during the protocol and regained weight during recovery, but animals that worked in the rest phase did not fully recover, even after eight days of recovery. In conclusion, three to four days of work in the rest phase is sufficient to induce disruption of several metabolic parameters, which requires more than eight days for full recovery.
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