School-Based Sleep Education Program for Children: A Cluster Randomized Controlled Trial.

Insufficient sleep contributes negatively to child developmental processes and neurocognitive abilities, which argues the need for implementing interventions to promote sleep health in children. In this study, we evaluated the effectiveness of a multimodal and multilevel school-based sleep education program in primary school children using a cluster randomized controlled design. Twelve schools were randomly assigned to either the sleep education or nonactive control groups. The sleep education group included a town hall seminar, small class teaching, leaflets, brochures, and a painting competition for children. Parents and teachers were invited to participate in a one-off sleep health workshop. Parental/caregiver-reported questionnaires were collected at baseline and 1-month follow-up. A total of 3769 children were included in the final analysis. There were no significant improvements observed in the sleep-wake patterns, daytime functioning, and insomnia symptoms between the two groups at follow-up, whereas the intervention group had significantly improved parental sleep knowledge than the controls (paternal: adjusted mean difference: 0.95 [95% confidence interval (CI): 0.18 to 1.71]; maternal: adjusted mean difference: 0.87 [95% CI: 0.17 to 1.57]). In addition, children receiving the intervention had a lower persistence rate of excessive beverage intake (adjusted odds ratio: 0.49 [95% CI: 0.33 to 0.73]), and experienced greater reductions in conduct problems (adjusted mean difference: 0.12 [95% CI: 0.01 to 0.24]) compared with the controls at 1-month of follow-up. Moreover, a marginally significant reduction for emotional problems in the intervention group was also observed (adjusted mean difference: 0.16 [95% CI: -0.00 to 0.32]). These findings demonstrated that school-based sleep education was effective in enhancing parental sleep knowledge and improving behavioral outcomes in children, but not sufficient in altering the children's sleep-wake patterns and sleep problems.

Isolated dream-enactment behaviours as a prodromal hallmark of rapid eye movement sleep behaviour disorder.

Recurrent dream-enactment behaviours (DEB) and rapid eye movement (REM) sleep without atonia (RSWA) are two diagnostic hallmarks of REM sleep behaviour disorder (RBD), a specific prodrome of α-synucleinopathy. Whilst isolated RSWA (without DEB) was suggested as a prodrome of RBD, the implication of 'isolated' recurrent DEB remains under-investigated. In this cross-sectional study, we sought to investigate neurodegenerative markers amongst the first-degree relatives (FDRs, aged >40 years) of patients with RBD who underwent clinical assessment for DEB, neurodegenerative markers, and video-polysomnography assessment. Isolated recurrent DEB was defined as: (i) three or more episodes of DEB, (ii) had a DEB episode in the past 1 year, and (iii) subthreshold RSWA. We identified 29 FDRs (mean [SD] age 53.4 [8.3] years, 55.2% male) with isolated recurrent DEB and 98 age and sex-matched FDRs as controls. Isolated DEB was associated with nightmare (27.6% versus 11.2%, p = 0.02), and the DEB group had a higher rate of current smoking (27.6% versus 3.1%, p = 0.006), type 2 diabetes mellitus (24.1% versus 10.2%, p = 0.003), anxiety disorder (24.1% versus 11.2%, p = 0.02), and constipation (hard lump of stool, 31.0% versus 7.1%, p < 0.001) than the control group. The present findings revealed that family relatives of patients with RBD with isolated recurrent DEB have increased risk of RBD and neurodegenerative features, which adds to the emerging data that isolated DEB is a prodromal feature of RBD and α-synucleinopathy neurodegeneration.

The impact of sleep-corrected social jetlag on mental health, behavioral problems, and daytime sleepiness in adolescents.

STUDY OBJECTIVES: This study aimed to examine the effect of sleep-corrected social jetlag (SJLsc) on mental health, behavioral problems, and daytime sleepiness in adolescents. METHODS: This was a cross-sectional study which included 4787 adolescents (Mean age: 14.83±1.6y, 56.0% girls) recruited from 15 secondary schools in Hong Kong. SJLsc was defined as the absolute difference between sleep-corrected midsleep on weekdays and weekends, at which the sleep debt has been considered. It was classified into three groups: low-level ("LSJLsc", <1h), mid-level ("MSJLsc", ≥1h and <2h), and high-level of SJLsc ("HSJLsc", ≥2h). Adolescents' mental health, behavioral problems and daytime sleepiness were measured by the General Health Questionnaire (GHQ-12), the Strengths and Difficulties Questionnaire (SDQ) and the Pediatric Daytime Sleepiness Scale (PDSS). Logistic regression analysis and restricted cubic spline regression (RCS) analysis were applied with consideration of confounders including age, gender, puberty and sleep problems. RESULTS: Nearly half (46.9%) of adolescents had SJLsc for at least 1 h. Greater SJLsc was associated with more behavioral difficulties (MSJLsc: OR: 1.20, p = 0.03; HSJLsc: OR: 1.34, p = 0.02) when controlling for age, sex, puberty, chronotype, insomnia, and time in bed. There was a dose-response relationship in which higher SJLsc had an increased risk of conduct problems and hyperactivity, while only high-level SJLsc was associated with a peer relationship problem. In RCS analysis, SJLsc was associated with a higher likelihood of behavioral difficulties (p = 0.03) but not poor mental health or daytime sleepiness. CONCLUSIONS: Sleep-corrected social jetlag was a unique risk factor for behavioral problems in adolescents. Our findings highlighted the need for interventions to promote healthy sleep-wake patterns in school adolescents.

Prevalence and correlates of REM sleep behaviour disorder in patients with major depressive disorder: a two-phase study.

OBJECTIVE: To investigate the prevalence and clinical correlates of video polysomnography (vPSG)-confirmed rapid eye movement sleep behaviour disorder (RBD) in patients with major depressive disorder (MDD). METHODS: This is a clinic-based two-phase epidemiological study. In phase 1, patients with MDD were screened by a validated questionnaire, RBD Questionnaire-Hong Kong (RBDQ-HK). In phase 2, a subsample of both the screen-positive (RBDQ-HK >20) and screen-negative patients with MDD underwent further clinical and sleep assessment (vPSG) to confirm the diagnosis of RBD (MDD+RBD). Poststratification weighting method was used to estimate the prevalence of MDD+RBD. The total likelihood ratio and the probability of prodromal Parkinson's disease (PD) were calculated from prodromal markers and risk factors, as per the Movement Disorder Society research criteria. RESULTS: A total of 455 patients with MDD were screened (median age (IQR)=52.66 (15.35) years, 77.58% woman, 43.74% positive). Eighty-one patients underwent vPSG and 12 of them were confirmed MDD+RBD. The prevalence of MDD+RBD was estimated to be 8.77% (95% CI: 4.33% to 16.93%), with possibly male predominance. MDD+RBD were associated with colour vision and olfaction deficit and a higher probability for prodromal PD. CONCLUSIONS: Almost 9% of patients with MDD in the psychiatric outpatient clinic has vPSG-confirmed RBD. Comorbid MDD+RBD may represent a subtype of MDD with underlying α-synucleinopathy neurodegeneration. Systematic screening of RBD symptoms and necessity of vPSG confirmation should be highlighted for capturing this MDD subtype with a view to enhance personalised treatment and future neuroprotection to prevent neurodegeneration.

A Prevention Program for Insomnia in At-risk Adolescents: A Randomized Controlled Study.

OBJECTIVES: To prevent the future development of insomnia in at-risk adolescents. METHODS: A randomized controlled trial comparing 4 weekly insomnia prevention program with a nonactive control group. Subjects were assessed at baseline, postintervention, and 6 and 12 months after intervention. Assessors were blinded to the randomization. Analyses were conducted on the basis of the intention-to-treat principles. RESULTS: A total of 242 adolescents with family history of insomnia and subthreshold insomnia symptoms were randomly assigned to an intervention group (n = 121; mean age = 14.7 ± 1.8; female: 51.2%) or control group (n = 121; mean age = 15.0 ± 1.7; female: 62.0%). There was a lower incidence rate of insomnia disorder (both acute and chronic) in the intervention group compared with the control group (5.8% vs 20.7%; P = .002; number needed to treat = 6.7; hazard ratio = 0.29; 95% confidence interval: 0.12-0.66; P = .003) over the 12-month follow-up. The intervention group had decreased insomnia symptoms (P = .03) and reduced vulnerability to stress-related insomnia (P = .03) at postintervention and throughout the 12-month follow-up. Decreased daytime sleepiness (P = .04), better sleep hygiene practices (P = .02), and increased total sleep time (P = .05) were observed at postintervention. The intervention group also reported fewer depressive symptoms at 12-month follow-up (P = .02) compared with the control group. CONCLUSIONS: A brief cognitive behavioral program is effective in preventing the onset of insomnia and improving the vulnerability factors and functioning outcomes.

Residual Injurious Symptoms and Its Association With Neurodegenerative Outcomes in Idiopathic Rapid Eye Movement Sleep Behavior Disorder: A Retrospective, Longitudinal Follow-up Study.

BACKGROUND: The risk of neurodegenerative disorders in idiopathic rapid eye movement sleep behavior disorder (iRBD) patients with residual injurious symptoms (RIS) after symptomatic treatment with clonazepam and/or melatonin is unclear. OBJECTIVE: The objective of this study was to determine the rate and correlates of RIS and its association with the risk of neurodegenerative diseases in patients with iRBD. METHODS: This was a retrospective cohort study. RIS was defined by the RBD Questionnaire-Hong Kong (RBDQ-HK) as the presence of residual sleep-related injuries or potential injurious behaviors for at least once a month after at least 1 year of treatment. RESULTS: A total of 15 out of 133 (11.3%) patients with iRBD (age at diagnosis = 66.5 ± 7.3 years, 77.4% male) had RIS after 2.7 years of treatment. Patients with RIS were younger at both onset and polysomnography-confirmed diagnosis of iRBD (years, mean ± standard deviation, 56.3 ± 6.9 vs. 61.8 ± 7.6, P = 0.01; 61.2 ± 4.2 vs. 67.2 ± 7.4, P < 0.001, respectively), had more severe behavioral symptoms at diagnosis (both RBDQ-HK total score and behavioral subscore, P = 0.01), and used a higher maximum dose of clonazepam (mg; median [interquartile range], 1.5 [1.0] vs. 1.0 [1.0], P = 0.01). RIS was probably associated with a higher risk of developing dementia with Lewy bodies (adjusted hazard ratio [95% confidence interval], 5.47 [1.71-17.46], adjusted for onset age of RBD), but not Parkinsons's disease in the follow-up. CONCLUSION: RIS is not uncommon in patients with iRBD despite long-term medication treatment. An earlier onset and more severe clinical profile are associated with RIS. The prediction of RIS toward dementia with Lewy bodies but not PD suggests that RIS may probably help to identify the specific risk of different subtypes of α-synucleinopathy. © 2020 International Parkinson and Movement Disorder Society.

Rest-Activity Pattern Alterations in Idiopathic REM Sleep Behavior Disorder.

OBJECTIVE: The purpose of this study was to investigate the differences in actigraphy-measured rest-activity patterns (eg, sleep-wake cycle, circadian rest-activity rhythm, and physical activity) across different stages of α-synucleinopathy. METHODS: We compared alterations in 7-day actigraphy-measured rest-activity patterns among patients with clinically diagnosed α-synucleinopathies (n = 44), and their age-, sex-, and body mass index (BMI)-matched patients with idiopathic rapid eye movement (REM) sleep behavior disorder (iRBD, n = 88), and non-rapid eye movement (REM) sleep behavior disorder (RBD) controls (n = 44) in a case-control study (study 1) and between convertors (n = 22) and their age-, sex-, BMI-, iRBD-duration, and follow-up duration-matched non-convertors (n = 66) in a prospective nested case-control study (study 2). RESULTS: In study 1, there were significant increases (all p values were adjusted by false discovery rate < 0.01) in probable napping behaviors (percentage, duration, and episodes), activity fragmentation (estimated by kAR ), and physical inactivity during active periods across controls, and iRBD, to clinically diagnosed α-synucleinopathies. In study 2, higher levels (all p values were adjusted by false discovery rate < 0.05) of baseline objective probable napping, activity fragmentation, and physical inactivity during active periods were associated with the conversion of patients with iRBD into clinically diagnosed α-synucleinopathies at 2 years of follow-up with medium to large effect sizes (Cohen's d: 0.56 to 0.80). These findings were further supported by functional linear modeling analyses. INTERPRETATION: Rest-activity pattern alterations, mainly objective probable napping behaviors, activity fragmentation, and physical inactivity during active period, emerge as early as at the stage of iRBD, which serves as early and robust prodromal markers of the conversion of iRBD into clinically diagnosed α-synucleinopathies. ANN NEUROL 2020;88:817-829.

Electromyography activity level in rapid eye movement sleep predicts neurodegenerative diseases in idiopathic rapid eye movement sleep behavior disorder: a 5-year longitudinal study.

OBJECTIVES: To investigate whether baseline electromyography (EMG) activity during rapid eye movement (REM) sleep predicts the development of neurodegenerative diseases over time in patients with idiopathic REM sleep behavior disorder (iRBD). METHODS: A total of 216 patients with polysomnography-confirmed iRBD were recruited from September 1997 to December 2016 with a mean follow-up duration of 5.0 ± 3.7 years (median: 4.0, range: 0.5-19.0). Neurodegenerative diseases were ascertained according to standard diagnostic criteria during follow-up. Time-dependent receiver operating characteristic (ROC) curves were employed to evaluate the dynamic predictive performance of EMG activity over time. Both tonic and phasic EMG activity were dichotomized into 'mild' and 'severe' categories by the ROC curves estimated optimal cut-offs. RESULTS: A total of 58 patients (26.9%) developed neurodegenerative diseases. The predictive performance of tonic EMG activity was stable (area under the curve of approximately 0.68) over time, while the performance of phasic EMG activity was significantly superior to chance only after five years of follow-up. The optimal cut-off for prediction at five years was 15.4% (sensitivity, 0.69; specificity, 0.57) and 7.8% (sensitivity, 0.79; specificity, 0.47) for tonic and phasic EMG activity, respectively. Cox proportional hazards regression analyses further revealed that severe tonic (adjusted HR: 2.76, 95% CI: 1.35-5.62) and phasic EMG activity (adjusted HR: 3.10, 95% CI: 1.10-8.71) were associated with early development of Parkinson's disease (PD) and dementia with Lewy bodies (DLB), respectively. CONCLUSIONS: Tonic but not phasic EMG activity may serve as a stable biomarkers for predicting the progression of neurodegeneration in iRBD.

A case-control-family study of idiopathic rapid eye movement sleep behavior disorder.

OBJECTIVE: To determine the familial aggregation of idiopathic rapid eye movement sleep behavior disorder (iRBD), neurodegenerative diseases, and related biomarkers. METHODS: A total of 404 and 387 first-degree relatives of 102 patients with iRBD and of 89 controls were recruited, respectively. Among them, 204 and 208 relatives of patients and controls underwent face-to-face clinical assessment, whereas 97 and 75 relatives underwent further video-polysomnographic assessment, respectively. RESULTS: Compared with relatives of controls, relatives of patients demonstrated higher levels of RBD features, including chin tonic electromyography activity (mean = 1.5 ± 7.5 vs 0.3 ± 1.0, p = 0.04) and behavioral events (n [weighted %] = 12 [11.3] vs 2 [1.9], adjusted hazard ratio [aHR] = 7.69, 95% confidence interval [CI] = 1.54-33.33, p = 0.009) during rapid eye movement sleep, probable diagnosis (n [%] = 57 [14.9] vs 20 [4.9], aHR = 3.45, 95% CI = 1.96-6.25, p < 0.001), and definite diagnosis (n [weighted %] = 10 [8.4] vs 2 [1.4], aHR = 5.56, 95% CI = 1.16-25.00, p = 0.03). They also had higher risks of Parkinson disease (3.1% vs 0.5%, aHR = 5.88, 95% CI = 1.37-25.00, p = 0.02), dementia (6.9% vs 2.6%, aHR = 2.44, 95% CI = 1.15-5.26, p = 0.02), constipation (8.3% vs 2.4%, adjusted odds ratio = 4.21, 95% CI = 1.34-13.17, p = 0.01), and motor dysfunction (Movement Disorders Society Unified Parkinson's Disease Rating Scale part III motor score, mean = 1.9 ± 3.2 vs 0.9 ± 2.3, p = 0.002). The unaffected relatives of patients demonstrated a higher likelihood ratio of prodromal Parkinson disease (median [interquartile range] = 0.27 [1.19] vs 0.22 [0.51], p = 0.03). INTERPRETATION: iRBD is familially aggregated from isolated features to full-blown sleep disorder. Relatives of patients carry a higher risk of alpha-synucleinopathy in terms of neurodegenerative diseases and prodromal markers, suggesting a familial aggregation and staging pathology of alpha-synucleinopathy. Ann Neurol 2019;85:582-592.

Excessive daytime sleepiness among children and adolescents: prevalence, correlates, and pubertal effects.

OBJECTIVES: To examine the prevalence and correlates of excessive daytime sleepiness (EDS) among Hong Kong children and adolescents. We investigated the potential roles of sex and puberty in modulating the occurrence of EDS. METHODS: A total of 10,086 students (male, 48.1%) aged 6-18 (mean ± SD: 12.3 ± 3.2) years old participated in this cross-sectional survey. EDS was defined by a total score >18 on the Pediatric Daytime Sleepiness Scale. Sociodemographic characteristics, time in bed, chronotypes, sleep problems, emotional and behavioral difficulties, mental health, and pubertal stages were assessed. RESULTS: The overall prevalence of EDS was 29.2%, and increased from 19.8% at Tanner stage 1 (pre-puberty) to 47.2% at Tanner stage 5 (post-puberty). Female predominance emerged at Tanner stage 3 (mid-puberty). EDS was significantly associated with short weekday time in bed, both long and short weekend time in bed, eveningness chronotype, insomnia symptoms, and sleep-disordered breathing symptoms. Females were more likely to have short weekday time in bed and eveningness chronotype than males. Children and young adolescents at pre and mid-puberty were protected against EDS by morningness chronotype. EDS was independently associated with daytime napping, alcohol and energy beverage consumption, emotional and behavioral difficulties, as well as poor mental health even after adjusting for potential confounding factors. CONCLUSIONS: EDS is prevalent among children and adolescents with the emergence of female preponderance at mid-puberty and independent association with pervasive adverse emotional and behavioral problems. The mechanisms underlying the modulation effects of sex and puberty on EDS merit further investigation.

Impact of a modest delay in school start time in Hong Kong school adolescents.

OBJECTIVE: To examine the effects of a modest delay (15 min) in school start time (SST) on adolescent sleep patterns, mood, and behaviors. METHODS: Two secondary schools in Hong Kong with a total of 1173 students (intervention: n = 617; comparison school n = 556) completed both baseline and follow-up questionnaires. School start time was delayed by 15 min, from 7:45 a.m. to 8:00 a.m., in the intervention school. The comparison school maintained their regular SST at 7:55 a.m. Students' sleep-wake patterns, daytime sleepiness, and mental and behavioral aspects were assessed by validated questionnaires before and after the intervention. RESULTS: Students in the intervention school significantly delayed their weekday wake-up time (p < 0.001) and increased their total time in bed (p < 0.001) when compared to students in the comparison school. Both groups experienced a delay in their weekday bedtime. The students in the intervention school showed improved mental health [General Health Questionnaire (GHQ) score, p = 0.015], better prosocial behaviors (p = 0.009), better peer relationships (p < 0.001), greater attentiveness (p < 0.001), less emotional problems (p = 0.002), and less behavioral difficulties (p < 0.001) as measured by Strengths and Difficulties Questionnaire (SDQ). CONCLUSIONS: A modest delay (15 min) in school start time can increase adolescent sleep with corresponding improvement in mood and behaviors. Current findings have significant implications for education policy, suggesting that school administrators and policy makers should systematically consider delaying school start time to promote sleep and health among school-aged adolescents. CLINICAL TRIAL REGISTRATION: ChiCTR-TRC-12002798. The trial protocol can be accessed at: http://www.chictr.org/en/proj/show.aspx?proj=3955.

Help-seeking behaviors for insomnia in Hong Kong Chinese: a community-based study.

OBJECTIVES: To determine the prevalence and correlates of help-seeking behaviors for insomnia in Hong Kong Chinese middle-aged adults and their offspring. METHODS: A total of 2231 middle-aged adults (54.2% females, mean age 45.8 years) and 2186 children and adolescents (51.9% females, mean age 13.4 years) completed a questionnaire on insomnia symptoms, daytime functioning, health condition and treatments sought for insomnia. RESULTS: A total of 40% of adults and 10% of children and adolescents with insomnia reported having sought treatment for insomnia. Conventional Western medicine was the commonly preferred treatment in 33.3% of adults and 13.3% of children and adolescents who sought help for insomnia, while a higher proportion of individuals with insomnia (34.5% of adults and 26.7% of children and adolescents) sought help from complementary and alternative medicine (CAM) therapies. Female gender (odds ratio [OR] [95% confidence interval, CI] = 2.14 [1.01-4.53]), higher family income (≥15,000 HKD/month) (OR [95% CI] = 3.15 [1.27-6.34]), severity of insomnia (Insomnia Severity Index ≥14) (OR [95% CI] = 2.12 [1.10-4.12]), chronic medications (OR [95% CI] = 4.71 [2.27-9.79]), and psychiatric disorders (OR [95% CI] = 2.83 [1.01-7.96]) were associated with help-seeking behaviors in adults. Presence of morning headache was associated with help-seeking behaviors in children and adolescents (OR [95% CI] = 8.66 [1.72-43.70]). CONCLUSIONS: It is uncommon for Hong Kong Chinese to seek help for insomnia, despite the high prevalence of insomnia. The significant unmet need argues for timely intervention to promote sleep-health literacy and to enhance the awareness and accessibility of evidence-based treatment for insomnia.

A prospective, naturalistic follow-up study of treatment outcomes with clonazepam in rapid eye movement sleep behavior disorder.

BACKGROUND: Rapid eye movement sleep behavior disorder (RBD) is characterized by prominent dream-enacting behaviors, often resulting in sleep-related injuries. OBJECTIVES: This study aimed to prospectively examine the treatment response of people with RBD treated with clonazepam, by quantitatively delineating the characteristic changes in the clinical and polysomnographic features, and to explore the factors associated with this response. METHODS: Patients diagnosed with idiopathic RBD (iRBD) were consecutively recruited and invited to complete clinical and polysomnographic (PSG) assessments and self-administered questionnaires (including the modified REM Sleep Behavior Questionnaire, RBDQ-3M) before and after the initiation of treatment with clonazepam. RESULTS: Thirty-nine iRBD patients (male: 74.4%, mean age at diagnosis: 68.3 ± 7.8 years) were recruited with a follow-up duration of 28.8 ± 13.3 months. Clonazepam was offered as the first-line treatment (starting dose: 0.43 ± 0.16 mg, range: 0.125-1.00; dose at follow-up: 0.98 ± 0.63 mg, range: 0.125-3). Treatment response, as defined by a complete elimination of sleep-related injuries and potentially injurious behaviors to self and/or to bed partner, at follow-up was reported in 66.7% of the overall study subjects. Frequency of disturbing dreams with violent and frightening content and vigorous behavioral RBD symptoms was significantly reduced, while residual nocturnal symptoms and an increase in REM-related EMG activities were observed at follow-up. Less optimal treatment outcomes were found to be associated with the presence of comorbid obstructive sleep apnea and earlier onset of RBD. CONCLUSIONS: Clonazepam differentially changes dream affect and content, as well as reduces vigorous verbal and motor behaviors. Residual RBD symptoms are common, despite treatment. Other more effective alternative or adjunctive interventions are needed for better clinical management of RBD.

Sleep Disturbances and Suicide Risk in an 8-Year Longitudinal Study of Schizophrenia-Spectrum Disorders.

STUDY OBJECTIVES: Disrupted sleep is one of the prominent but often overlooked presenting symptoms in the clinical course of psychotic disorders. The aims of this study were to examine the prevalence of sleep disturbances, particularly insomnia and nightmares, and their prospective associations with the risk of suicide attempts in patients with schizophrenia-spectrum disorders. METHODS: A naturalistic longitudinal study was conducted in outpatients diagnosed with schizophrenia-spectrum disorders recruited from the psychiatric outpatient clinic of a regional university-affiliated public hospital in Hong Kong. A detailed sleep questionnaire was completed by 388 patients at baseline in May-June 2006. Relevant clinical information was extracted from clinical case notes from June 2007-October 2014. RESULTS: Prevalence of frequent insomnia and frequent nightmares was 19% and 9%, respectively. Baseline frequent insomnia was significantly associated with an increased incidence of suicide attempts during the follow-up period (adjusted hazard ratio = 4.63, 95% confidence interval 1.40-15.36, P < 0.05). Nightmare complaint alone did not predict the occurrence of suicide attempts, but the comorbidity of nightmares and insomnia was associated with the risk of suicide attempt over follow-up (adjusted HR = 11.10, 95% confidence interval: 1.68-73.43, P < 0.05). CONCLUSIONS: Sleep disturbances are common in patients with schizophrenia-spectrum disorders. The association between sleep disturbances and suicidal risk underscores the need for enhanced clinical attention and intervention on sleep disturbances in patients with schizophrenia.

Altered Sleep Stage Transitions of REM Sleep: A Novel and Stable Biomarker of Narcolepsy.

OBJECTIVES: To determine the diagnostic values, longitudinal stability, and HLA association of the sleep stage transitions in narcolepsy. METHODS: To compare the baseline differences in the sleep stage transition to REM sleep among 35 patients with type 1 narcolepsy, 39 patients with type 2 narcolepsy, 26 unaffected relatives, and 159 non-narcoleptic sleep patient controls, followed by a reassessment at a mean duration of 37.4 months. RESULTS: The highest prevalence of altered transition from stage non-N2/N3 to stage R in multiple sleep latency test (MSLT) and nocturnal polysomnography (NPSG) was found in patients with type 1 narcolepsy (92.0% and 57.1%), followed by patients with type 2 narcolepsy (69.4% and 12.8%), unaffected relatives (46.2% and 0%), and controls (39.3% and 1.3%). Individual sleep variables had varied sensitivity and specificity in diagnosing narcolepsy. By incorporating a combination of sleep variables, the decision tree analysis improved the sensitivity to 94.3% and 82.1% and enhanced specificity to 82.4% and 83% for the diagnosis of type 1 and type 2 narcolepsy, respectively. There was a significant association of DBQ1*0602 with the altered sleep stage transition (OR = 16.0, 95% CI: 1.7-149.8, p = 0.015). The persistence of the altered sleep stage transition in both MSLT and NPSG was high for both type 1 (90.5% and 64.7%) and type 2 narcolepsy (92.3% and 100%), respectively. CONCLUSION: Altered sleep stage transition is a significant and stable marker of narcolepsy, which suggests a vulnerable wake-sleep dysregulation trait in narcolepsy. Altered sleep stage transition has a significant diagnostic value in the differential diagnosis of hypersomnias, especially when combined with other diagnostic sleep variables in decision tree analysis.

Eveningness and insomnia: independent risk factors of nonremission in major depressive disorder.

BACKGROUND: It is unclear whether there is an association between chronotype and nonremission of depression, and whether the association is related to the confounding effect of insomnia. METHOD: A cohort of patients with major depressive disorder were assessed for chronotype (by Morningness-Eveningness Questinnaire [MEQ]), depressive symptoms, insomnia severity and clinical outcomes in a naturalistic follow-up study. RESULTS: Of the 253 recruited subjects (age 50.8 ± 10.2 y; female: 82.6%; response rate 90.0%), 19.4%, 56.1% and 24.5% patients were classified as eveningness, intermediate, and morningness, respectively. Evening-type subjects had higher insomnia severity, more severe depressive symptoms, and higher suicidality. Eveningness was associated with nonremission of depression with an odds ratio (OR) of 3.36 (95% confidence interval [CI] 1.35-8.34, P < 0.01), independent of insomnia severity. In addition, insomnia was an independent significant factor in contributing to nonremission of depression (OR = 1.12; 95% CI 1.05-1.19, P < 0.001). CONCLUSION: The independent association of eveningness with nonremission of depression suggested a significant underpinning of circadian involvement in major depressive disorder. Our findings support the need for a comprehensive assessment of sleep and circadian disturbances as well as integration of sleep and chronotherapeutic intervention in the management of depression.

Does rapid eye movement sleep behavior disorder exist in psychiatric populations? A clinical and polysomnographic case-control study.

OBJECTIVES: Rapid eye movement (REM) sleep behavior disorder (RBD) has been increasingly reported in patients with psychiatric disorders (pRBD). Although a close association with the usage of psychotropics has been postulated, it remains elusive whether psychotropics are the only causative factor of RBD symptoms in psychiatric populations. Moreover, there is limited literature documenting and quantifying the clinical and polysomnographic features in this population. METHODS: A case-control study comparing the clinical and polysomnographic features of 31 pRBD patients with: (1) Age-, sex-, and psychiatric diagnoses-matched controls; and (2) Typical idiopathic RBD (tRBD) patients. RESULTS: Despite being prescribed with similar psychotropics, pRBD patients had more dream-enacting behaviors (p<0.01), sleep-related injuries (p<0.01), and nightmares (p<0.01) than the psychiatric controls. pRBD patients were younger with more females, but they had comparable sleep-related injuries to tRBD. Both tRBD and pRBD had more REM-related muscle activity than controls (p<0.01) and the effect remained significant after adjusting for age, gender, and use of antidepressants. CONCLUSIONS: Our study suggests that pRBD had comparable clinical features and consequences to those of tRBD. The occurrence of RBD symptoms in these patients may be related to a constellation of factors, including individual predisposition, depressive illness, antidepressants, and other clinical factors. Given the association of RBD and neurodegeneration in tRBD, further prospective follow-up of these patients is warranted.

Amelioration of obstructive sleep apnea in REM sleep behavior disorder: implications for the neuromuscular control of OSA.

OBJECTIVES: The relationship between REM sleep behavior disorder (RBD) and obstructive sleep apnea (OSA) remains unclear. We aimed to (1) explore the association of REM-related EMG activity (REMREEA) with OSA in RBD patients; (2) compare the severity of OSA between RBD patients with OSA (RBD-OSA) and their age-, sex-, AHI-, and BMI- matched OSA controls. DESIGN: a. Correlation study in consecutive RBD subjects and b. case-control study SETTING: Sleep laboratory PARTICIPANTS: 71 RBD patients in the correlation study and 55 subjects (28 RBD-OSA cases and 27 OSA controls) in the case-control study. INTERVENTION: N/A METHODS: Polysomnographic assessment to document the sleep architecture, sleep apnea related parameters, and REMREEA. RESULTS: (1) In the correlation study, increased REMREEA was associated with lower severity of OSA in RBD patients, including total AHI (r = -0.263), NREM AHI (r = -0.242), obstructive AHI (r = -0.265), and mean apnea duration (r = -0.353) (P < 0.05). (2) In the case-control study, RBD-OSA patients had lesser severity of sleep apnea parameters than OSA controls in terms of higher nadir SpO(2) (85.7% ± 4.9% vs 80.8% ± 5.9%, P < 0.01), shorter maximum hypopnea duration (53.8 ± 16.7 vs 69.4 ± 22.4 seconds, P < 0.05), and maximum (45.8 ± 20.5 vs 60.8 ± 19.6 sec, P < 0.01) and mean apnea duration (22.3 ± 8.1 vs 26.3 ± 5.8 sec, P < 0.05). Significant interaction effects indicated that the usual REM sleep exacerbation of sleep apneas was seen only in OSA controls but not in RBD subjects. CONCLUSIONS: This study demonstrated that excessive EMG activity in RBD might protect patients against severe OSA and suggests this may be a naturalistic model for understanding neuromuscular control of OSA.

Frequent nightmares in children: familial aggregation and associations with parent-reported behavioral and mood problems.

STUDY OBJECTIVES: To conduct a systematic investigation on the prevalence, correlates, and familial aggregation of frequent nightmares in children, and to scrutinize the associations between frequent nightmares and parent-reported behavioral and mood problems in children. DESIGN: A cross-sectional study was conducted by collecting the data on sociodemographic, sleep, behavioral, and family-related information from a total of 6359 children (age: mean [SD]=9.2 [1.8] years; girls: 49.9%) and their reported biological parents. SETTING: Community. INTERVENTIONS: N/A. MEASUREMENTS AND RESULTS: Prevalence of frequent nightmares with a criterion of at least once per week was 5.2%. Multinomial regression analysis indicated that monthly family income, paternal and maternal nightmares, insomnia symptoms, parasomniac symptoms, and daytime consequences were significantly associated with nightmares in children. Frequent nightmares in children were significantly associated with hyper-activity (odds ratio [OR]=1.68, 95% CI 1.16-2.44), frequent temper outbursts/mood disturbance (OR=1.76, 95%CI 1.27-2.44), and poor academic performance (OR=1.62, 95% CI 1.11-2.36), after controlling for potential confounding factors. Approximately 20% of children with frequent nightmares experienced comorbid frequent insomnia. Comorbid nightmares and insomnia were associated with increased odds of hyperactivity (OR=4.13, 95% CI 2.13-8.00) and frequent temper outbursts/mood disturbance (OR=2.41, 95%CI 1.27-4.60). CONCLUSIONS: Frequent nightmares in children are associated with a constellation of child-, sleep-, and family-related factors, including comorbid sleep problems, such as insomnia and parasomnia, family economic status, and parental predisposition. Frequent nightmares are independently associated with emotional and behavioral problems in children.