Siu Ping Lam

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.

Prospective outcome of rapid eye movement sleep behaviour disorder: psychiatric disorders as a potential early marker of Parkinson's disease

Increasing evidence suggests that rapid eye movement sleep behaviour disorder (RBD) is a heralding feature associated with evolving α-synucleinopathy-related neurodegenerative disorders.1–4 Several neurobiological markers such as olfactory abnormality were associated with the development of neurodegenerative disorders in ‘idiopathic’ RBD (iRBD) patients.5 On the other hand, pre-morbid psychiatric disorders were suggested as an important but often neglected preclinical marker of Parkinsons disease (PD),6 and its role is unclear in iRBD patients. The current study aimed to provide a quantitative risk estimate of neurodegenerative outcome, and to investigate the role of psychiatric disorders in predicting future neurodegenerative disorders in a prospective cohort of Hong Kong Chinese iRBD patients. Ninety-one iRBD patients (82.4% men) (recruited during 1994–2009) were prospectively followed-up with routine clinical assessments in our sleep centre for a mean duration of 5.6 years (SD 3.3).1 An additional research-based follow-up protocol has been implemented since 2008, which included neuropsychiatric examinations as conducted by the research …

REM sleep behaviour disorder in Hong Kong Chinese: clinical outcome and gender comparison

REM sleep behaviour disorder (RBD) is a parasomnia characterised by a history of dream-enactment behaviours during REM sleep, resulting in shouting, punching, jerking, kicking, falling out of bed and sleep-related injuries (SRI).1–3 The estimated prevalence rate of RBD was similarly about 0.4–0.5% in both Caucasian and Hong Kong Chinese elderly populations. There were only few large clinical series of RBD of Caucasian descents.1–3 Hence, we aimed to report our RBD series for cross-cultural comparison of clinical and gender-related findings. View this table: Table 1 Comparison of demographic data, clinical features, comorbidities and treatment efficacy among reported case series From 1994 to 2006, 82 patients (male: 81.7%) were diagnosed to have RBD according to the International Classification of Sleep Disorder (1st and 2nd editions) in our sleep clinic, which was a main centre in receiving clinical referrals from different disciplines locally. The mean age of onset and diagnosis was 62.1 (SD 12.9) and 67.4 (SD 10.0) years, respectively. Sleep talking, shouting, vigorous movements of arms and legs were commonly reported nocturnal behaviours. Dream recall was available in 75.6% patients (62/82). The violent themes emerged from their dreams consisted of active defence against others (50%, 31/62), defence against animals (17.7%, 11/62) and aggression towards others (24.2%, 15/62). Two patients (3.2%) reported dreams of being chased by a ghost, …

Longitudinal course and outcome of chronic insomnia in Hong Kong Chinese children: A 5-year follow-up study of a community-based cohort

OBJECTIVES There are limited data on the long-term outcome of childhood insomnia. We explored the longitudinal course, predictors, and impact of childhood insomnia in a community-based cohort. DESIGN 5-year prospective follow-up. SETTING Community-based. PARTICIPANTS 611 children (49% boys) aged 9.0 ± 1.8 years at baseline; 13.7 ± 1.8 years at follow-up. INTERVENTION NA. MAIN EXPOSURES Chronic insomnia was defined as difficulty initiating sleep, difficulty maintaining sleep and/or early morning awakening ≥ 3 times/week in the past 12 months. OUTCOME MEASURES General health, upper airway inflammatory diseases, and behavioral problems in recent one year were assessed at both time points, while mental health and lifestyle practice were assessed at follow-up study. The questionnaires at baseline and follow-up were reported by parents/caretakers and adolescents themselves, respectively. RESULTS The prevalence of chronic insomnia was 4.2% and 6.6% for baseline and follow-up, respectively. The incidence and persistence rates of chronic insomnia were 6.2% and 14.9%, respectively. New incidence of insomnia was associated with lower paternal education level, baseline factors of frequent temper outbursts and daytime fatigue as well as alcohol use and poor mental health at follow-up. Baseline chronic medical disorders, frequent temper outbursts, and poor mental health at follow-up were associated with the persistence of insomnia in adolescents. Baseline insomnia was associated with frequent episodes of laryngopharyngitis and lifestyle practice (coffee and smoking) at follow-up. CONCLUSIONS Chronic insomnia is a common problem with moderate persistent rate in children. The associations of adverse physical and mental health consequences with maladaptive lifestyle coping (smoking and alcohol) argue for rigorous intervention of childhood insomnia.

Insomnia, sleep quality, pain, and somatic symptoms: sex differences and shared genetic components.

TOC summary A shared genetic predisposition might underlie the associations of insomnia and sleep quality with pain and somatic symptoms. Insomnia seems to modulate the sex differences in pain and somatic symptoms, especially in the adult population. Abstract This study investigated the sex differences, and the shared genetic and environmental factors underlying the associations of sleep disturbances (insomnia and sleep quality) with pain and somatic symptoms in both adolescents and middle‐aged adults. We recruited 259 adolescents (69 with current insomnia) and their parents (256 middle‐aged adults, 78 with current insomnia). Insomnia severity and sleep quality were measured by the Insomnia Severity Inventory (ISI) and Pittsburgh Sleep Quality Index (PSQI), respectively. Pain and somatic symptoms were measured by the Somatic Symptom Inventory and Visual Analogue Scale for overall pain. Subjects with insomnia scored higher on all measures of pain and somatic symptoms than non‐insomnia patients, in both adolescents and adults (P < .001). Both pain and somatic measures were associated with ISI and PSQI scores after controlling for age, sex, depressive and anxiety symptoms. There was an interaction effect between insomnia and female sex on pain and somatic symptoms (P < .05), especially in adults. Pain and somatic symptoms ran in family with moderate heritability (range h2 = 0.15–0.42). The phenotypic associations of ISI and PSQI with pain and somatic measures were both contributed by genetic (range pG = 0.41–0.96) and environmental (range pE = 0.27–0.40) factors with a major genetic contribution. In summary, insomnia and poor sleep quality are closely associated with pain and somatic symptoms. Insomnia seems to modulate the sex differences in pain and somatic symptoms, especially in the adult population. A shared genetic predisposition might underlie the associations of insomnia and sleep quality with pain and somatic symptoms.

A School-Based Sleep Education Program for Adolescents: A Cluster Randomized Trial

OBJECTIVES: To evaluate the effectiveness of a multilevel and multimodal school-based education program. METHODS: A cluster randomized controlled trial with 14 secondary schools in Hong Kong and a total of 3713 students (intervention: 1545 vs control: 2168; 40.2% boys; mean age ± SD: 14.72 ± 1.53 years) were included in the final analysis. The intervention included a town hall seminar, small class workshops, a slogan competition, a brochure, and an educational Web site. Their parents and teachers were offered sleep education seminars. The control schools did not receive any sleep program. Data were collected before and 5 weeks after the intervention. RESULTS: The students in the intervention group had significantly improved sleep knowledge compared with the control group (mean difference: 3.64 [95% confidence interval (CI): 3.21 to 4.07]; Cohen’s d = 0.51) as measured by using a sleep knowledge questionnaire. Weekday sleep duration was reduced in both groups, and the significant difference in weekday sleep duration was lost in the intention-to-treat analysis (mean difference: 0:01 [95% CI: –0:00 to 0:04]). In addition, the intervention group had a lower incidence of consuming caffeine-containing energy drinks (adjusted odds ratio: 0.46 [95% CI: 0.22 to 0.99]) and had better behavioral (mean difference: –0.56 [95% CI: –1.02 to –0.10]; Cohen’s d = 0.13) and mental health (mean difference: –0.30 [95% CI: –0.15 to –0.46]; Cohen’s d = 0.11) outcomes. CONCLUSIONS: A school-based sleep education program was effective in enhancing sleep knowledge and improving behavioral and mental health, but it had no significant impact on sleep duration or pattern among adolescents.

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.

The longitudinal course and impact of non-restorative sleep: A five-year community-based follow-up study

BACKGROUND There is a dearth of data on the longitudinal course and outcome of non-restorative sleep (NRS). METHODS A total of 2291 middle-aged adults (mean [SD]=46.3 [5.1] years old, 50.0% males at follow-up) were recruited into a 5-year follow-up study. NRS was defined as morning unfreshness after getting up ≥ 3 times/week over the past 12 months. Socio-demographics, other concurrent sleep complaints, and daytime symptoms were measured at baseline. Chronic medical problems in the past one year were additionally assessed at follow up. RESULTS Several sleep problems (including other insomnia subtypes, snoring, and nightmares) and daytime symptoms were strongly associated with NRS at baseline. NRS had considerable persistence (31.9%), partial remission (22.7%), and incidence rate (5.2%). New incidence of NRS was predicted by female gender (AOR=1.67), preferring not to get up in the morning (AOR=1.96), fatigue (AOR=2.18), and short sleep duration (AOR=1.87), whereas persistence of NRS was predicted by difficulty initiating sleep (AOR=2.36). In the fully adjusted models, baseline NRS was significantly associated with multiple medical disorders at follow-up, including frequent allergic rhinitis (AOR=1.62) and laryngopharyngitis (AOR=2.47), diabetes mellitus (AOR=2.63), gastroesophageal reflux disease (AOR=2.03), eye problems (AOR=2.45), eczema (AOR=2.18), and poor mental health (AOR=1.68). CONCLUSIONS The persistent course and independent association of NRS with adverse medical and mental outcomes argue for a distinct nosological status and the need for rigorous medical attention.

Reduced striatal dopamine transmission in REM sleep behavior disorder comorbid with depression

Objective: To investigate dopamine transmission in patients with comorbid REM sleep behavior disorder (RBD) and major depressive disorder (MDD). Methods: This is a case-control study including 11 medicated patients with comorbid RBD and MDD (mean age 47.5 ± 8.2), 8 medicated patients with MDD only (mean age 47.9 ± 8.4), and 10 healthy participants (mean age 46.5 ± 10.6 years). They underwent clinical assessment, video-polysomnography, olfactory tests, and neuroimaging studies (18F-DOPA, 11C-raclopride, and 18F-FDG PET neuroimaging). Results: Compared with the 2 control groups, patients with comorbid RBD and MDD had significantly lower 18F-DOPA uptake at 60 minutes in the putamen and caudate after controlling for age and sex effect (p < 0.05). There were no significant differences for the 11C-raclopride and 18F-FDG-PET. The 18F-DOPA uptake in putamens had significant inverse correlation with severity of RBD symptoms (p < 0.01) and REM-related tonic muscle activity (p < 0.01). The comorbid RBD and MDD group had more impairment in olfactory function. Conclusion: Patients with comorbid RBD and MDD had presynaptic dopamine dysfunction and impaired olfactory function. There is a distinct possibility that the development of RBD symptoms among patients with MDD may represent an early phase of α-synucleinopathy neurodegeneration instead of a merely antidepressant-induced condition.

A Community-Based Study on the Association Between Insomnia and Hypothalamic-Pituitary-Adrenal Axis: Sex and Pubertal Influences

CONTEXT The association between insomnia disorder and the hypothalamic-pituitary-adrenal (HPA) axis needs to be explored in both adults and adolescents. OBJECTIVES Our objective was to investigate the associations of the HPA axis (via serial salivary cortisol) with insomnia disorder and subjective and objective sleep quality in a community-based study. DESIGN AND SETTING This was a community-based case-control family study. PARTICIPANTS Participants included 205 adolescents (14.2 ± 2.8 years old, 51.7% females, and 57 with insomnia) and 244 adults (46.4 ± 4.1 years old, 52.8% females, and 69 with insomnia). MAIN OUTCOME MEASURES Outcome measures included a diagnostic interview for assessment of insomnia disorder, 3-day actigraphy and sleep diary, and serial salivary cortisol measurement. RESULTS Adults with insomnia had a significantly greater cortisol awakening response (CAR) reference to increase (CARi) but a comparable CAR reference to ground and a comparable cortisol level during afternoon and evening when compared with noninsomniac adults. The association between insomnia disorder and larger CARi was also found in adolescents at late/post puberty but not in pre/early pubertal adolescents. There was an interaction effect between sex and insomnia disorder on CARi level with adult females having larger CARi than adult males. Among subjects with insomnia disorder, those with lower subjective sleep efficiency had higher cortisol levels in the late evening (10:00 pm) in both adults and adolescents. CONCLUSIONS Our study suggests that a series of insomniac indices at both syndromal and symptomatic levels including clinical diagnosis and poor sleep quality are associated with dysfunction of the HPA axis. The association between insomnia and increased CARi emerges at late puberty, and the sex difference in this association occurs in adulthood but not in adolescence.