Shirley Xin Li

Validation of a new REM sleep behavior disorder questionnaire (RBDQ-HK)☆

OBJECTIVES There are limited screening instruments for diagnosis of REM sleep behavior disorder (RBD) and none for quantifying the severity of disease. We aimed to validate a 13-item self-reported RBD questionnaire (RBDQ-HK) for diagnostic and monitoring purposes. METHODS Based on ICSD-II and our previous clinical and empirical work, the RBDQ-HK questionnaire was designed and administered in patients attending university-affiliated sleep clinic and psychiatric out-patient clinic, and subjects from the general population. ROC curve and exploratory factor analysis were employed to evaluate the scale, which had a score ranging from 0 to 100. RESULTS One hundred and seven RBD patients [mean age 62.6 (15.5) years; male 70.1%] and 107 control subjects [mean age 55.3 (9.0) years, male 57.9%] completed the questionnaire. The diagnoses of all the study subjects were independently ascertained by clinical interview and PSG. RBD patients had a significantly higher total RBDQ-HK score [mean (s.d.): 32.1 (16.1), range 3-71] than the control group [9.5 (10.2), range 0-55] (p<0.005). The RBDQ-HK demonstrated robust psychometric properties with moderate sensitivity (82.2%), specificity (86.9%), positive predictive value (PPV; 86.3%), and negative predictive value (NPV; 83.0%), high internal consistency and test-retest reliability. Exploratory factor analysis revealed two components (dream-related and behavioral factors) that corresponded to the essential clinical features of RBD. The best cut-off for total score (range 0-100) was at 18/19 and the best cut-off for factor 2 (behavioral factors including sleep talking, shouting, limb movements and sleep-related injuries, range 0-70) was at 7/8. CONCLUSIONS The RBDQ-HK has satisfactory validity and reliability as a measure of clinical RBD symptoms and severity. It may serve as an effective tool for diagnosis and evaluation of the disease course to facilitate future clinical and research studies.

The Effect of Weekend and Holiday Sleep Compensation on Childhood Overweight and Obesity

OBJECTIVES: A growing trend in childhood sleep habits is to compensate for the weekday sleep deficit by longer weekend and holiday sleep duration. We aimed to investigate the effect of weekend/holiday sleep compensation in relation to childhood overweight and obesity. METHODS: This is a community-based cross-sectional study with 5159 children (49.6% boys), mean age of 9.25 years (SD: 1.78), from 13 primary schools in Hong Kong. Data on sleep patterns, lifestyle, body weight, and height of children were obtained from questionnaires. Sleep durations during weekdays, weekends, and holidays were predictor variables. BMI z scores and obesity/overweight status were the outcome measures. RESULTS: Children slept significantly longer during holidays (mean [SD]: 10.20 (0.92) hours) and weekends (school terms) (10.07 [0.93] hours) than during school weekdays (9.18 [0.95] hours). Children with shorter sleep duration had higher BMI z scores regardless of the sleep parameters used in the analysis. Among children who slept <8 hours during weekdays, those children who did not compensate for their sleep deficit during weekends or holidays had significantly increased risk of overweight/obesity compared with those children with sleep compensation (odds ratios: 2.59 [95% confidence interval: 1.22–5.48] and 2.32 [95% confidence interval: 1.00–5.53], respectively). CONCLUSIONS: There was a prominent difference in sleep duration between weekdays and weekends/holidays among school children. Short sleep duration was associated with higher BMI, but compensation of sleep during weekends/holidays may partly ameliorate the risk of childhood overweight/obesity. Further prospective and interventional study is needed to delineate the risk-benefit effect of these increasingly common sleep habits among children and adolescents.

Nocturnal sleep disturbances as a predictor of suicide attempts among psychiatric outpatients: a clinical, epidemiologic, prospective study

OBJECTIVE Nocturnal sleep disturbances, including insomnia and recurrent nightmares, represent common distressing sleep complaints that might have important prognostic and therapeutic implications in psychiatric patients. The present study aimed at investigating nocturnal sleep disturbances in relation to the risk of suicide attempts in a consecutive cohort of psychiatric outpatients. METHOD Participants attending a psychiatric outpatient clinic in Hong Kong were recruited into the study with a detailed sleep questionnaire assessment. The questionnaire was distributed between May and June 2006. Relevant clinical information, with a comprehensive clinical history of patients since their attendance at psychiatric services and 1 year after completion of their questionnaires, was reviewed. RESULTS The final study population consisted of 1,231 psychiatric outpatients with a mean age of 42.5 years (SD = 11.3; range, 18-65). Both frequent insomnia and recurrent nightmares were significantly and independently associated with an increased incidence of suicide attempts 1 year after questionnaire assessment (insomnia: OR = 6.96; 95% CI, 1.21-39.97; recurrent nightmares: OR = 8.17; 95% CI, 1.06-63.13) and an increase in lifetime prevalence of suicide attempts (insomnia: OR = 1.55; 95% CI, 1.06-2.25; recurrent nightmares: OR = 2.43; 95% CI, 1.51-3.91). Comorbid insomnia and nightmares had increased odds of lifetime prevalence (OR = 2.43; 95% CI, 1.53-3.85) and 1-year incidence of suicidal risk (OR = 17.08; 95% CI, 2.64-110.40). Antidepressants, particularly selective serotonin reuptake inhibitors (OR = 1.52; 95% CI, 1.02-2.25), serotonin-norepinephrine reuptake inhibitors (OR = 2.10; 95% CI, 1.15-3.83), heterocyclics (OR = 2.78; 95% CI, 1.21-6.42), and non-benzodiazepine hypnotics (OR = 1.54; 95% CI, 1.02-2.33) were independently associated with recurrent nightmares after adjustment for confounding variables. CONCLUSIONS Nocturnal sleep disturbances, particularly frequent insomnia and recurrent nightmares, were independently associated with enhanced suicidal risk among psychiatric patients. Future studies are warranted to investigate the underlying pathophysiologic mechanism and interventional responses.

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, …

Long-term outcomes and predictors of chronic insomnia: A prospective study in Hong Kong Chinese adults

OBJECTIVES We aimed to determine the longitudinal course and outcome of chronic insomnia in a five-year prospective study in Hong Kong Chinese adults. METHODS Two thousand three hundred and sixteen middle-aged adults (53.3% females, 46.3 ± 5.1 years old at follow-up) were recruited at baseline and follow-up. Participants were divided into three groups: non-insomnia, insomnia symptoms, and insomnia syndrome (insomnia symptoms plus daytime symptoms). Upper airway inflammatory diseases, mental problems, and medical problems were additionally assessed at follow up. RESULTS The incidence of insomnia (symptoms and syndrome) was 5.9%. The persistence rate of insomnia syndrome was 42.7% for insomnia syndrome and 28.2% for insomnia symptoms. New incidence of insomnia was associated with younger age, unemployment, and daytime symptoms, while persistence of insomnia was associated with female sex, lower education level, and daytime symptoms at the baseline (p<0.05). Baseline insomnia syndrome was significantly associated with upper airway inflammatory diseases (including asthma and laryngopharyngitis; adjusted OR=1.97-17.9), mental problems, and medical conditions (including arthritis, psychiatric disorders, chronic pain, and gastroesophageal reflux disease; AOR=2.29-3.77), whereas baseline insomnia symptoms were associated with poor mental health (AOR=2.43), psychiatric disorders (AOR=2.39), and chronic pain (AOR=2.95). CONCLUSIONS Chronic insomnia is a common problem with considerable persistence and incidence rates among middle-aged Chinese adults. Insomnia syndrome has a higher persistence rate with more mental and medical comorbidities when compared with insomnia symptoms without daytime consequences.

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.

Residual sleep disturbances in patients remitted from major depressive disorder: a 4-year naturalistic follow-up study.

STUDY OBJECTIVES To investigate the prevalence and clinical, psychosocial, and functional correlates of residual sleep disturbances in remitted depressed outpatients. DESIGN A 4-yr prospective observational study in a cohort of psychiatric outpatients with major depressive disorder was conducted with a standardized diagnostic psychiatric interview and a packet of questionnaires, including a sleep questionnaire, Hospital Anxiety and Depression Scale, NEO personality inventory, and Short Form-12 Health Survey. SETTINGS A university-affiliated psychiatric outpatient clinic. INTERVENTIONS N/A MEASUREMENTS AND RESULTS: Four hundred twenty-one depressed outpatients were recruited at baseline, and 371 patients (mean age 44.6 ± 10.4 yr, female 81.8%; response rate 88.1%) completed the reassessments, in which 41% were classified as remitted cases. One year prevalence of frequent insomnia at baseline and follow-up in remitted patients was 38.0% and 19.3%, respectively. One year prevalence of frequent nightmares at baseline and follow-up was 24.0% and 9.3%, respectively. Remitted patients with residual insomnia were more likely to be divorced (P < 0.05) and scored higher on the anxiety subscale (P < 0.05). Remitted patients with residual nightmares were younger (P < 0.05) and scored higher on neuroticism (P < 0.05) and anxiety subscales (P < 0.01). Residual insomnia and nightmares were associated with various aspects of impaired quality of life. Residual nightmares was associated with suicidal ideation (odds ratio = 8.40; 95% confidence interval 1.79-39.33). CONCLUSIONS Residual sleep disturbances, including insomnia and nightmares, were commonly reported in remitted depressed patients with impaired quality of life and suicidal ideation. A constellation of psychosocial and personality factors, baseline sleep disturbances, and comorbid anxiety symptoms may account for the residual sleep disturbances. Routine assessment and management of sleep symptoms are indicated in the integrated management of depression.

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.