Depressed mood and repetitive negative thinking in Delayed Sleep-Wake Phase Disorder: Treatment effects and a comparison with good sleepers

Group bright light therapy compared to treatment as usual for delayed sleep-wake phase disorder among patients in psychiatric care (the SIP trials): a protocol for a pragmatic, randomised controlled trial

INTRODUCTION

Circadian rhythm sleep-wake disturbances appear to be prevalent in psychiatric populations and may maintain and exacerbate psychiatric symptoms. Bright light therapy (BLT) is, in addition to exogenous melatonin, the treatment of choice for circadian rhythm disorders like delayed sleep-wake phase disorder (DSWPD) and has yielded promising results in patients with comorbid psychiatric illness. However, such patients are rarely offered this treatment in outpatient clinics. The aim of this randomised controlled trial is to investigate whether group BLT for psychiatric outpatients is superior to treatment as usual (TAU).

METHODS AND ANALYSIS

60 patients with moderate-to-severe psychiatric illness who meet the criteria for DSWPD will be recruited from an outpatient psychiatric clinic in Norway. They will be randomised (1:1) to a group-based Sleep School Wake Up! For Circadian (SSWU-C) programme conjointly with TAU or to TAU while on a wait list for SSWU-C. The SSWU-C will be delivered over four biweekly sessions, each lasting 120 min; hence treatment will last 6 weeks. Assessments will be collected at baseline (T1) and after the intervention (T2). The primary outcome will be changes in sleep timing using measures such as sleep diaries, actigraphy and dim light melatonin onset (DLMO) at 6 weeks postintervention. Secondary outcomes include changes in other sleep metrics, symptoms of depression, anxiety, fatigue, problems with work and social adjustment and well-being. Mixed models will be used for data analyses.

ETHICS AND DISSEMINATION

Ethical approval was granted in 2020 by the Regional Ethics Committee in Western Norway (REK 2020/66304). Findings will be published in peer-reviewed journals and be presented at research conferences and in relevant media. The results may document the need for more specific sleep-directed treatments in psychiatric clinics as a way of treating not only circadian rhythm sleep-wake disorders but also as a treatment to alleviate psychiatric symptoms.

TRIAL REGISTRATION NUMBER

NCT05177055.

Efficacy of digital brief behavioural treatment for insomnia using a smartphone application in conjunction with light therapy in university students with insomnia symptoms with late chronotypes: A pilot randomized-controlled trial

The efficacy of digital brief behavioural treatment for insomnia using a smartphone application in conjunction with light therapy was investigated in university students who had insomnia symptoms with late chronotypes. In this two-arm parallel randomized-controlled trial, participants with insomnia symptoms and late chronotypes were recruited between October and November 2023. The duration of the intervention program was 4 weeks. The smartphone application provides digital brief behavioural treatment for insomnia, including programs for advanced phases. The intervention group used blue-light-emitting diode glasses in the morning after waking up for 2-4 weeks. The primary outcome was a change in the Insomnia Severity Index during the study period. The Insomnia Severity Index was obtained weekly using a web questionnaire. Of the 28 students, 14 each were assigned to the intervention and control groups. The mean Insomnia Severity Index scores at baseline were 12.2 and 12.5; after 4 weeks, they declined to 7.2 and 10.6 in the intervention and control groups, respectively. Primary analysis using a linear mixed model showed a significant improvement in the temporal trends of the Insomnia Severity Index in the intervention group (p < 0.001). The scores on the Morningness-Eveningness Questionnaire (p = 0.008) and RU-SATED (p = 0.005) significantly improved in the intervention group relative to the control group following the intervention. This study demonstrated the effectiveness of the digital brief behavioural treatment for insomnia with light therapy in participants with both insomnia symptoms and late chronotypes.

Depressive symptoms, sleep-wake features, and insomnia among female students: The role of rumination

Depression symptoms are prevalent among nursing students, especially those in Asia. This study assessed the association between rumination and depression symptoms among female nursing students (N = 148) and the chain mediation role of sleep-wake indexes and insomnia symptoms. The data were collected from a battery of questionnaires and consecutive 7-day actigraphy data for analyzing sleep-wake indexes. About 54.1% of the participants had either mild or moderate depression symptoms. Most students (89.2%) had a delayed circadian phase, and circadian activity rhythm (CAR) was not ideal. The path mediation model underwent analysis using the PROCESS macros. The results showed that rumination in students is directly positively correlated with depressive symptoms (b = 4.831). Moreover, the association between rumination and depressive symptoms is sequent (moderating effect = 0.12, 95% CI [0.017, 0.410]). The proposed model in this study provides a foundation for improving educational programs on sleep hygiene and promoting mental wellness.

The Association Between Delayed Sleep-Wake Phase Disorder and Depression Among Young Individuals: A Systematic Review and Meta-Analysis: Association entre le syndrome de retard de phase et la dépression parmi les jeunes : revue systématique et méta-analyse

ObjectivesDelayed sleep-wake phase disorder (DSWPD) most commonly affects young individuals (adolescents and young adults), but it is often undetected in clinical practice. Despite several reports suggesting a link between DSWPD and depression, no systematic review has investigated this association. The aim of this systematic review was to determine whether DSWPD is associated with depression among young individuals.MethodsMEDLINE, EMBASE, PsycINFO, and CINAHL Plus were searched up to 29 July 2024. Primary studies investigating DSWPD and depression among young individuals were eligible. Methodological quality and risk of bias was assessed with the National Institute of Health (NIH) Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies. Common-effect models were conducted to examine the relationship between DSWPD status (categorical variable: yes or no) and depression severity (continuous variable). PROSPERO ID: CRD42023458889.ResultsSixteen studies were included with 766 participants being evaluated against the diagnostic criteria for DSWPD from the International Classification of Sleep Disorders. Thirteen out of 15 studies demonstrated that young individuals with DSWPD had a significantly greater severity of depressive symptoms than young individuals without DSWPD. NIH quality assessment scores ranged between 5 and 9 (out of a total of 11). DSWPD status had a significantly large effect on depression severity in the common-effect model (N: 16 estimates, 693 participants, Cohen's d = 0.92, 95% confidence interval (95% CI) [0.76-1.08]). The subgroup analysis also demonstrated significant findings with the common-effect model that only utilized data from studies that controlled for psychiatric disorders (N: 12 estimates, 535 participants, Cohen's d = 0.88, 95% CI [0.70-1.06]).ConclusionsDSWPD is associated with a greater severity of depressive symptoms among young individuals. Although more research is required to understand this association, it may be useful to consider the presence of DSWPD when managing young individuals who present with persistent sleep disturbances (e.g., sleep-onset insomnia) and depressive symptoms.

General procrastination associated with the evening preference in healthy people but not with circadian rhythm sleep-wake disorders with phase delay

Procrastination behavior has been reportedly associated with the evening preference. This study aimed to evaluate its difference between patients with circadian rhythm sleep-wake disorders with phase delay (CRSWDswPD) and healthy controls in terms of evening preference and comorbid psychiatric disorders. Thirty patients with CRSWDswPD and 29 healthy participants were included. In both groups, the general procrastination scale (GPS), Beck Depression Inventory (BDI), and Morningness-Eveningness Questionnaire (MEQ) were administered. Additionally, Adult ADHD Self-Report Scale (ASRS) and autism spectrum quotient (AQ) were also assessed in the patient group. Unexpectedly, GPS was not statistically different between patients with CRSWDswPD and healthy controls. GPS was significantly higher with lower MEQ in the healthy group, whereas the opposite tendency was observed in the patient group. Higher AQ, ASRS, and BDI tended to be associated with higher GPS in the patient group, with the first two being statistically significant. The results suggest that general procrastination is not significantly associated with CRSWDswPD, although it is associated with evening preference in healthy participants. Procrastination in the patient group may be associated with developmental disorders or depression tendencies. Future studies should include simultaneous measurement of circadian markers, other behavioral assessments, a larger population, and untreated patients.

Negative interpretation bias and repetitive negative thinking as mechanisms in the association between insomnia and depression in young adults

OBJECTIVES

Despite evidence supporting sleep's role in the development and maintenance of depression, mechanisms underlying this association in young people are less established. Negative interpretation bias (the tendency to interpret ambiguous situations negatively) and repetitive negative thinking (RNT) are important candidate mechanisms. Whilst negative interpretation bias is implicated in depression development, it is a transdiagnostic process and may result from insomnia. Yet, research relating to these constructs is lacking. RNT is another transdiagnostic process implicated in association between negative interpretation bias, depression and insomnia. However, an elaborated model that includes both mechanisms is yet to be tested. It was hypothesised that negative interpretation bias and RNT would sequentially mediate the relationship between sleep/insomnia and depressive symptoms in young people.

DESIGN

The associations predicted by this hypothesis were tested via cross-sectional mediation in a sample of 214 participants (Mage = 19.19 years, SD = 1.67, Rangeage = 17-24 years, 20% male).

METHODS

Participants completed questionnaire measures of insomnia symptoms, depression symptoms and RNT, an ambiguous scenarios task and a 1-week sleep diary.

RESULTS

Results were consistent with negative interpretation bias and RNT as sequential mechanisms which partially account for the relationship between sleep (i.e., insomnia severity and sleep parameters) and depression.

CONCLUSIONS

This study supports negative interpretation bias and RNT as mechanisms linking insomnia and depression in young people, as the predicted associations between these variables were observed. Future research should investigate the causal/directional associations. However, results support theoretical models, and suggest sleep, interpretation bias and RNT may be important processes to target in preventing and treating depression.

Negative attention bias and attentional control as mechanisms in the association between insomnia and depression in young people

Evidence supports a causal role of insomnia in the development and maintenance of depression, yet mechanisms underlying this association in young people are not well established. Attention biases have been implicated separately in the sleep and depression fields and represents an important candidate mechanism. Poor sleep may lead to a negative attention bias (characteristic of depression) by impacting attentional control. This study assessed the hypothesis that attentional control and negative attention bias would sequentially mediate the relationship between insomnia and depressive symptoms in an unselected sample of young people (17-24 years). Concerns have been raised regarding the psychometric properties of tasks used to measure attention bias, and a Dual-Probe Task is emerging as a more reliable measure. Participants (N = 275, Male = 59, Mage = 19.40) completed the Dual-Probe Task, a behavioural measure of attentional control, and self-report measures of insomnia and depression. Participants completed a one-week sleep diary. Results were consistent with negative attention bias, but not attentional control, as a mechanism which partially accounts for the relationship between sleep (i.e., insomnia severity, sleep duration, sleep efficiency, sleep latency) and depression. This study highlights sleep and negative attention bias as potentially modifiable risk factors to reduce depressive symptoms in young people.

Sleep-wake behavioral characteristics associated with depression symptoms: findings from the Multi-Ethnic Study of Atherosclerosis

STUDY OBJECTIVES

To help prioritize target/groups for experimental intervention studies, we characterized cross-sectional associations between 24-hour sleep-wake measures and depression symptoms, and evaluated if similar sleep-wake-depression relationships existed in people with and without higher insomnia severity.

METHODS

Participants had ≥3 days of actigraphy data (n = 1884; mean age = 68.6/SD = 9.1; 54.1% female). We extracted 18 sleep, activity, timing, rhythmicity, and fragmentation measures from actigraphy. We used individual and multivariable regressions with the outcome of clinically significant depression symptoms (Center for Epidemiologic Studies Depression Scale ≥ 16). We conducted sensitivity analyses in people with higher insomnia severity (top quartile of the Women's Health Initiative Insomnia Rating Scale total score).

RESULTS

From separate models in the overall sample, the odds of having depression symptoms were higher with: later timing (e.g. activity onset time odds ratio [OR]/1 SD = 1.32; 95% confidence interval [CI]: 1.16 to 1.50), lower rhythmicity (e.g. pseudo-F OR/1 SD = 0.75; 95% CI: 0.66 to 0.85), less activity (e.g. amplitude OR/1 SD = 0.83; 95% CI: 0.72 to 0.95), and worse insomnia (OR/1 SD = 1.48, 95% CI: 1.31 to 1.68). In multivariable models conducted among people with lower insomnia severity, later timing, lower rhythmicity, and higher insomnia severity were independent correlates of depression. In people with higher insomnia symptom severity, measures of later timing were most strongly associated with depression symptoms.

CONCLUSIONS

These correlative observations suggest that experimental studies are warranted to test if: broadly promoting 24-hour sleep-wake functioning reduces depression even in people without severe insomnia, and if advancing timing leads to depression symptom reductions in people with insomnia.

The role of rumination in the relationship between symptoms of insomnia and depression in adolescents

There is a strong relationship between the symptoms of insomnia and depression, however, little is understood about the factors that mediate this relationship. An understanding of these underlying mechanisms may inform the advancement of existing treatments to optimise reductions in insomnia and depression when they co-occur. This study examined rumination and unhelpful beliefs about sleep as mediators between symptoms of insomnia and depression. It also evaluated the effect of cognitive behavioural therapy for insomnia (CBT-I) on rumination and unhelpful beliefs about sleep, and whether these factors mediated the effect of CBT-I on depressive symptoms. A series of mediation analyses and linear mixed modelling were conducted on data from 264 adolescents (12-16 years) who participated in a two-arm (intervention vs. control) randomised controlled trial of Sleep Ninja®, a CBT-I smartphone app for adolescents. Rumination, but not unhelpful beliefs about sleep, was a significant mediator between symptoms of insomnia and depression at baseline. CBT-I led to reductions in unhelpful beliefs about sleep, but not in rumination. At the between-group level, neither rumination, nor unhelpful beliefs about sleep emerged as mechanisms underlying improvement in depression symptoms, however, rumination mediated within-subject improvements following CBT-I. The findings suggest rumination links symptoms of insomnia and depression and provide preliminary evidence that reductions in depression following CBT-I occurs via improvements in rumination. Targeting rumination may improve current therapeutic approaches.

Photoperiod and metabolic health: evidence, mechanism, and implications

Circadian rhythms are evolutionarily programmed biological rhythms that are primarily entrained by the light cycle. Disruption of circadian rhythms is an important risk factor for several metabolic disorders. Photoperiod is defined as total duration of light exposure in a day. With the extended use of indoor/outdoor light, smartphones, television, computers, and social jetlag people are exposed to excessive artificial light at night increasing their photoperiod. Importantly long photoperiod is not limited to any geographical region, season, age, or socioeconomic group, it is pervasive. Long photoperiod is an established disrupter of the circadian rhythm and can induce a range of chronic health conditions including adiposity, altered hormonal signaling and metabolism, premature ageing, and poor psychological health. This review discusses the impact of exposure to long photoperiod on circadian rhythms, metabolic and mental health, hormonal signaling, and ageing and provides a perspective on possible preventive and therapeutic approaches for this pervasive challenge.

Bright Light Therapy for Major Depressive Disorder in Adolescent Outpatients: A Preliminary Study

BACKGROUND

Bright light therapy (BLT) has not been well-studied in adolescents with major depressive disorder, particularly in outpatient settings.

METHODS

We conducted an 8-week clinical trial of BLT in adolescents recruited from a primary care practice with moderate to severe major depression. Acceptability and feasibility were defined by daily use of the light box and integration into daily routines. To assess treatment effects, we utilized the Short Mood and Feelings Questionnaire (SMFQ) and actigraphic sleep variables.

RESULTS

Of the nine enrolled adolescents, the rate of daily use of the light therapy box was 100% at week 2, 78% at week 4 (n = 7), and 67% at weeks 6 and 8 (n = 6). Participants were better able to integrate midday BLT compared to morning BLT into their day-to-day routines. Mean depression scores improved during the 2-week placebo lead-in (dim red light-DRL) and continued to show significant improvement through 6 weeks of BLT. Sleep efficiency increased significantly (p = 0.046), and sleep onset latency showed a trend toward a significant decrease (p = 0.075) in the BLT phase compared to the DRL phase.

CONCLUSION

Bright light treatment that was self-administered at home was feasible, acceptable, and effective for adolescent outpatients with depression. Findings support the development of larger, well-powered, controlled clinical trials of BLT in coordination with primary care.

Circadian light therapy and light dose for depressed young people: a systematic review and meta-analysis

Background

Empirical evidence has shown that light therapy (LT) can reduce depression symptoms by stimulating circadian rhythms. However, there is skepticism and inconclusive results, along with confusion regarding dosing. The purpose of this study is to quantify light as a stimulus for the circadian system and create a dose-response relationship that can help reduce maladies among adolescents and young adults (AYAs). This will provide a reference for light exposure and neural response, which are crucial in the neuropsychological mechanism of light intervention. The study also aims to provide guidance for clinical application.

Methods

The latest quantitative model of CLA (circadian light) and CSt,f (circadian stimulus) was adopted to quantify light dose for circadian phototransduction in youth depression-related light therapy. Articles published up to 2023 through Web of Science, Cochrane Library, Medline (OVID), CINAHL, APA PsycINFO, Embase, and Scholars were retrieved. A meta-analysis of 31 articles (1,031 subjects) was performed using Stata17.0, CMA3.0 (comprehensive meta-analysis version 3.0) software, and Python 3.9 platform for light therapy efficacy comparison and dose-response quantification.

Results

Under various circadian stimulus conditions (0.1 < CSt,f < 0.7) of light therapy (LT), malady reductions among AYAs were observed (pooled SMD = -1.59, 95%CI = -1.86 to -1.32; z = -11.654, p = 0.000; I2 = 92.8%), with temporal pattern (p = 0.044) and co-medication (p = 0.000) suggested as main heterogeneity sources. For the efficacy advantage of LT with a higher circadian stimulus that is assumed to be influenced by visualization, co-medication, disease severity, and time pattern, sets of meta-analysis among random-controlled trials (RCTs) found evidence for significant efficacy of circadian-active bright light therapy (BLT) over circadian-inactive dim red light (SMD = -0.65, 95% CI = -0.96 to -0.34; z = -4.101, p = 0.000; I2 = 84.9%) or circadian-active dimmer white light (SMD = -0.37, 95% CI = -0.68 to -0.06; z = -2.318, p = 0.02; I2 = 33.8%), whereas green-blue, circadian-active BLT showed no significant superiority over circadian-inactive red/amber light controls (SMD = -0.21, 95% CI = -0.45 to 0.04; z = -2.318, p = 0.099; I2 = 0%). Overall, circadian-active BLT showed a greater likelihood of clinical response than dim light controls, with increased superiority observed with co-medication. For pre-to-post-treatment amelioration and corresponding dose-response relationship, cumulative duration was found more influential than other categorical (co-medication, severity, study design) or continuous (CSt,f) variables. Dose-response fitting indicated that the therapeutic effect would reach saturation among co-medicated patients at 32-42 days (900-1,000 min) and 58-59 days (1,100-1,500 min) among non-medicated AYAs. When exerting high circadian stimulus of light therapy (0.6 < CSt,f < 0.7), there was a significantly greater effect size in 1,000-1,500 min of accumulative duration than <1,000 or >1,500 min of duration, indicating a threshold for practical guidance.

Limitations

The results have been based on limited samples and influenced by a small sample effect. The placebo effect could not be ignored.

Conclusions

Although the superiority of LT with higher circadian stimulus over dimmer light controls remains unproven, greater response potentials of circadian-active BLT have been noticed among AYAs, taking co-medication, disease severity, time pattern, and visual characteristics into consideration. The dose-response relationship with quantified circadian stimulus and temporal pattern had been elaborated under various conditions to support clinical depression treatment and LT device application in the post-pandemic era.

Early time-restricted eating advances sleep in late sleepers: a pilot randomized controlled trial

STUDY OBJECTIVES

This study evaluated the effects of early time-restricted eating (eTRE) on shifting the timing of sleep among late sleepers. Primary outcomes included actigraphy- and sleep diary-derived sleep onset, midsleep phase, and wake time with total sleep time as a secondary outcome.

METHODS

Fifteen healthy adults with habitual late sleep timing were randomized to receive either eTRE or sleep and nutrition hygiene (control) via a single 30-minute synchronous video session. Participants completed an initial 1-week baseline phase followed by a 2-week intervention phase. Measures included continuous sleep monitoring and sleep and nutrition diaries.

RESULTS

Linear mixed-effects modeling demonstrated that eTRE significantly advanced sleep timing compared with controls. Self-reported sleep onset (56.1 [95% confidence interval: 20.5, 91.7] minutes), midpoint (19.5 [7.2, 31.9] minutes), and offset (42.2 [2.9, 81.5] minutes) each moved earlier in eTRE as compared with controls. Similarly, objectively determined sleep onset (66.5 [29.6, 103.4] minutes), midpoint (21.9 [9.1, 34.7] minutes), and offset (39.3 [1.3, 77.3] minutes) each moved earlier in eTRE as compared with controls. Total sleep time showed a nonsignificant increase in the eTRE group as compared with controls.

CONCLUSIONS

Late sleepers who were instructed in a single session about eTRE significantly advanced their sleep timing, especially sleep onset. eTRE shows potential as a clinical strategy for advancing sleep timing in late sleepers.

CLINICAL TRIAL REGISTRATION

Registry: Chinese Clinical Trial Registry; Name: FAST Asleep: It's All About Timing; URL: https://www.chictr.org.cn/showproj.html?proj=122504; Identifier: ChiCTR2100043691.

CITATION

Blum DJ, Hernandez B, Zeitzer JM. Early time-restricted eating advances sleep in late sleepers: a pilot randomized controlled trial. J Clin Sleep Med. 2023;19(12):2097-2106.

Using Nightly Sleep Guidelines to Address Links Between Adolescents' Self-Reported Weekly Sleep Patterns and Anxiety and Depression Symptoms

Short and long nightly sleep durations are associated with anxiety and depression symptoms among adolescents. However, studies have not used recommended hours of nightly sleep or focused on sleep patterns across weekdays and weekends in examining links with anxiety and depression symptoms. The present study included 709 adolescents in Grade 11 (402 females; 307 males) who self-reported hours of sleep on weeknights and weekends and anxiety and depression symptoms. Using the recommended 8-10 h to define average nightly sleep for adolescents, sleep patterns across weekdays and weekends were categorised into seven classes: short stable, short increasing, average decreasing, average stable, average increasing, long decreasing, and long stable. Relative to average stable sleepers, short stable, short increasing, and long stable sleepers had significantly higher anxiety and depression. Adolescents require 8-10 h of sleep on weeknights, regardless of weekends, for optimal emotional wellbeing.

Light Therapy for Adolescent Depression: A Scoping Review

PURPOSE

Depressive disorders in adolescents are a major health concern associated with developmental, social, and educational impairment. Bright Light Therapy (BLT) is a feasible and effective treatment for depressive disorders in adults, but few controlled trials have been conducted with children or adolescents. This scoping review focuses on the current state of knowledge for BLT in the treatment of adolescent depression. We reviewed the literature for novel data and methodologic approaches using BLT and pediatric and young adult populations.

RECENT FINDINGS

BLT is a tolerable treatment with few side effects. However, there is a marked lack of well-powered studies to support BLT as a treatment for depressive disorders in adolescent populations. Given evidence of tolerability and positive treatment effect on depression in the adult literature, research is needed to establish the efficacy, feasibility, and acceptability of BLT in adolescents.

Efficacy of a Combination Therapy for Difficulties Waking Up in Non-School-Attending Students

School non-attendance due to difficulties waking up is increasing in Japan, and affected students are commonly diagnosed with orthostatic dysregulation (OD); however, OD-associated sleep problems are overlooked. To date, no sleep-medicine-based treatment for wake-up difficulties in non-school-attending students has been established. This study aimed to assess the efficacy of a novel combination therapy for these students. We assessed the combined effect of sleep hygiene guidance, low-dose aripiprazole administration (3 mg/day), and blue-light exposure on wake-up difficulty in 21 non-school-attending teenage patients. The patients were evaluated using sleep studies and questionnaires before and after treatment. The average subjective total sleep time calculated from sleep diaries before treatment in the patients was 10.3 h. The therapy improved wake-up difficulty by 85.7% and further improved school non-attendance by 66.7%. The subjective sleep time significantly decreased by 9.5 h after treatment (p = 0.0004). The self-rating Depression Scale and mental component summary of the 36-item Short-Form Health Survey significantly improved after treatment (p = 0.002 and p = 0.01, respectively). Wake-up difficulties were caused by the addition of a delayed sleep phase to the patients’ long sleep times. The novel combination therapy was effective in improving wake-up difficulty and mental quality of life in non-school-attending teenage students.

The Clinical Effect of Blue Light Therapy on Patients with Delayed Sleep-Wake Phase Disorder

OBJECTIVE

To investigate the feasibility and patient acceptance of applying blue light glasses to treat delayed sleep-wake phase disorder (DSWPD).

METHODS

Fifteen patients with DSWPD were collected as the observation group and 15 healthy people as the control group. The patients wore blue light glasses with a continuous radiation wavelength of about 470 nm for 1h to 2h during the period from 06:30 to 09:00 in the morning after waking up, respectively. Assessment of Hamilton Anxiety Scale 14 items (HAMA14), Hamilton Depression Rating Scale 24 items (HAMD24), Pittsburgh Sleep Quality Index (PSQI), Epworth Sleepiness Scale (ESS), Morningness-Eveningness Questionnaire (MEQ), and Insomnia Severity Index (ISI) scores before and after 1 week of treatment. Pearson correlation was used to analyze the correlation between the efficacy of patients with sleep-wake phase delay disorder and HAMA14, HAMD24, PSQI, ISI, ESS, MEQ, SL (sleep time), TST (total sleep time), TTiB (total time in bed), SQ (sleep quality), TOA (total arousal time), WASO (wake after sleep onset), AAT (average arousal time), and SE (sleep efficiency percent). Multi-factor logistic regression analysis of factors influencing the efficacy of patients with sleep-wake phase delay disorder.

RESULTS

After treatment, PSQI-G scores, number of nighttime awakenings and time of awakening recorded in the sleep diary decreased significantly in the observation group (P < 0.05), and subjective sleep quality and MEQ scores increased (P < 0.05). MEQ score shifted from "moderate night type" to "intermediate type", sleep-wake phase tended to shift forward. The total PSQI score and Pittsburgh Sleep Quality Index Global (PSQI-G) score were significantly lower in the control group after treatment (P < 0.05). By Pearson correlation analysis, the efficacy of patients with sleep-wake phase delay disorder was significantly correlated with HAMA14, HAMD24, PSQI, ISI, ESS, MEQ, SL, TST, TTiB, SQ, TOA, WASO, AAT, and SE. Multifactorial logistic regression analysis revealed that the factors influencing the efficacy of patients with sleep-wake phase delay disorder were PSQI, ISI, ESS, MEQ, SL, TST, TTiB, SQ, TOA, WASO, AAT, and SE.

CONCLUSION

Blue light therapy has a positive effect on improving subjective sleep quality, reducing the number of nocturnal awakenings and the duration of nocturnal awakenings, improving daytime function, and shifting the sleep phase forward in patients with DSWPD. Blue light therapy improves subjective sleep quality and daytime function the following day in normal individuals.