Nocturnal agitation: From sleep state dissociation to sleep-related dissociative state.

Nocturnal agitation refers to a broad spectrum of symptoms from simple movements to aggressive behaviors with partial or complete loss of awareness. An accurate identification of its etiology is critical for appropriate therapeutic intervention. In children and young adults, distinguishing between non-rapid eye movement (NREM) sleep parasomnias and psychogenic non-parasomniac manifestations, a condition known as sleep-related dissociative disorder (SRDD), can be challenging. This review aims to summarize current clinical, neurophysiological, and epidemiological knowledge on NREM parasomnia and SRDD, and to present the pathophysiological hypotheses underlying these nocturnal manifestations. Sleepwalking, sleep terror and confusional arousals are the three main presentations of NREM parasomnias and share common clinical characteristics. Parasomniac episodes generally occur 30minutes to three hours after sleep-onset, they are usually short, lasting no more than few minutes and involve non-stereotyped, clumsy behaviors with frequent amnesia. The prevalence of NREM parasomnia decreases from 15-30% in children to 2-4% in adults. Parasomniac episodes are incomplete awakening from the deepest NREM sleep and are characterized by a dissociated brain activity, with a wake-like activation in motor and limbic structures and a preserved sleep in the fronto-parietal regions. SRDD is a less known condition characterized by dramatic, often very long episodes with frequent aggressive and potentially dangerous behaviors. SRDD episodes frequently occur in quiet wakefulness before falling asleep. These dissociative manifestations are frequently observed in the context of psychological trauma. The pathophysiology of SRDD is poorly understood but could involve transient changes in brain connectivity due to labile sleep-wake boundaries in predisposed individuals. We hypothesize that SRDD and NREM parasomnia are forms of sleep-related dissociative states favored by a sleep-wake state dissociation during sleep-onset and awakening process, respectively.

Transtornos relacionados ao sono e comportamentos sexuais anômalos / Sleep Disorders and abnormal sexual behaviors

Esse artigo se baseia nas publicações de Schenck, especialista no assunto. Parassonias são comportamentos sexuais anômalos relacionados ao sono, caracterizados por movimentos complexos, emoções, percepções, sonhos e atividade do sistema nervoso autônomo. Podem provocar lesões, interrupção do sono, efeitos adversos à saúde e psicossociais. O diagnóstico é clínico: história médica e antecedentes (relatos de parcerias ou familiares e vídeos domésticos). Polissonografia é reservada para casos atípicos. O tratamento inclui medidas protetivas, esclarecimento ao familiar/cônjuge, controle dos fatores precipitantes, medicamento (clonazepam) e psicoterapia. A sexônia é uma parassonia (subtipo não REM), melhor estudada. Masturbação e tentativas inadequadas de obter relações sexuais (seguidas de amnésia ou lembrança vaga) são frequentes. A frequência em clínicas do sono é de 7,6% (homens 11,0%; mulheres 4,0%). Esses comportamentos surgem no curso de longa história de parassonia, desencadeando despertares confusionais. Terapia nasal com pressão positiva contínua nas vias aéreas pode controlar. Em homens, ereção peniana, associada à sexônia, é referida pela parceria. Providência importante é inquirir sobre sexônia, quando houver suspeita, uma vez que o paciente e/ou sua parceria não costumam falar, a menos que sejam solicitados ou por questões legais. Revisão de 18 casos médico-legais sobre violência relacionada ao sono e comportamento sexual durante o sono encontrou 9 casos em que sexônia foi alegada pela defesa. Foram apresentadas avaliações dos réus, as quais diferiram de caso para caso, alertando para a necessidade de consenso internacional. Abuso de álcool desqualifica a "defesa baseada em parassonia [sexônia]" em casos médico-legais.

Big Data in sleep apnoea: Opportunities and challenges.

Sleep apnoea is now regarded as a highly prevalent systemic, multimorbid, chronic disease requiring a combination of long-term home-based treatments. Optimization of personalized treatment strategies requires accurate patient phenotyping. Data to describe the broad variety of phenotypes can come from electronic health records, health insurance claims, socio-economic administrative databases, environmental monitoring, social media, etc. Connected devices in and outside homes collect vast amount of data amassed in databases. All this contributes to 'Big Data' that, if used appropriately, has great potential for the benefit of health, well-being and therapeutics. Sleep apnoea is particularly well placed with regards to Big Data because the primary treatment is positive airway pressure (PAP). PAP devices, used every night over long periods by millions of patients across the world, generate an enormous amount of data. In this review, we discuss how different types of Big Data have, and could be, used to improve our understanding of sleep-disordered breathing, to identify undiagnosed sleep apnoea, to personalize treatment and to adapt health policies and better allocate resources. We discuss some of the challenges of Big Data including the need for appropriate data management, compilation and analysis techniques employing innovative statistical approaches alongside machine learning/artificial intelligence; closer collaboration between data scientists and physicians; and respect of the ethical and regulatory constraints of collecting and using Big Data. Lastly, we consider how Big Data can be used to overcome the limitations of randomized clinical trials and advance real-life evidence-based medicine for sleep apnoea.

Treating insomnia improves depression, maladaptive thinking, and hyperarousal in postmenopausal women: comparing cognitive-behavioral therapy for insomnia (CBTI), sleep restriction therapy, and sleep hygiene education.

INTRODUCTION: Depression increases during menopause, and subclinical depressive symptoms increase risk for major depression. Insomnia is common among postmenopausal women and increases depression-risk in this already-vulnerable population. Recent evidence supports the efficacy of cognitive-behavioral therapy for insomnia (CBTI) to treat menopausal insomnia, but it remains unclear whether treating insomnia also alleviates co-occurring depressive symptoms and depressogenic features. This trial tested whether CBTI improves depressive symptoms, maladaptive thinking, and somatic hyperarousal in postmenopausal women with insomnia; as well as whether sleep restriction therapy (SRT)-a single component of CBTI-is equally efficacious. MATERIALS AND METHODS: Single-site, randomized controlled trial. 117 postmenopausal women (56.34 ± 5.41 years) with peri-or-postmenopausal onset of chronic insomnia were randomized to three treatment conditions: sleep hygiene education control (SHE), SRT, and CBTI. Blinded assessments were performed at baseline, posttreatment, and six-month follow-up. RESULTS: CBTI produced moderate-to-large reductions in depressive symptoms, whereas SRT produced moderate reductions but not until six months posttreatment. Treatment effects on maladaptive thinking were mixed. CBTI and SRT both produced large improvements in dysfunctional beliefs about sleep, but weaker influences on presleep cognitive arousal, rumination, and worry. Presleep somatic arousal greatly improved in the CBTI group and moderately improved in the SRT group. Improvements in depression, maladaptive thinking, and hyperarousal were linked to improved sleep. SHE produced no durable treatment effects. CONCLUSIONS: CBTI and SRT reduce depressive symptoms, dysfunctional beliefs about sleep, and presleep somatic hyperarousal in postmenopausal women, with CBTI producing superior results. Despite its cognitive emphasis, cognitive arousal did not respond strongly or durably to CBTI. NAME: Behavioral Treatment of Menopausal Insomnia: Sleep and Daytime Outcomes. URL: clinicaltrials.gov. REGISTRATION: NCT01933295.

Neurocognitive performance in insomnia disorder: The impact of hyperarousal and short sleep duration.

Given the recent evidence on the association between hyperarousal in insomnia disorder and neurocognitive deficits, we aimed to examine the effect of short sleep duration on neurocognitive reaction time tests in insomnia disorder sufferers. We recruited subjects with insomnia disorder (n = 35, mean age = 40.6 years) who scored ≥29 on a Hyperarousal Scale, and a group of controls (n = 54, mean age = 31.5 years) who had no sleep disorders and scored <26 on the Hyperarousal Scale. Participants completed two in-home polysomnograms and four daytime trials of neurocognitive tests, including simple reaction time, choice reaction time, big circle-little circle, rapid visual information processing, attention switching task, and spatial working memory tests. Total sleep time divided study cohorts into subgroups of short (total sleep time <6 hr) and normal (total sleep time ≥6 hr) sleepers. ANCOVA showed a significant interaction between participant type (insomnia disorder versus controls) and sleep duration (short versus normal) for spatial working memory-latency (p = 0.020) and spatial working memory-errors (p = 0.025). The short-sleeping insomnia disorder group had longer spatial working memory-latencies and more spatial working memory-errors than did normal-sleeping controls. Regardless of sleep duration, those with insomnia disorder had more attentional deficits with longer attention switching task-latency (p = 0.011) and more attention switching task-incorrect trials (p = 0.015) than the control group. Normal-sleepers only had longer attention switching task-latency than short-sleepers (p = 0.004). A phenotype of insomnia disorder with hyperarousal and short sleep duration is associated with daytime cognitive deficits in complex attentional and spatial working memory tasks.

Comorbid sleep disorders and suicide risk among children and adolescents with bipolar disorder.

Children and adolescents with bipolar disorder are at increased risk for suicide. Sleep disturbances are common among youth with bipolar disorder and are also independently implicated in suicide risk; thus, comorbid sleep disorders may amplify suicide risk in this clinical population. This study examined the effects of comorbid sleep disorders on suicide risk among youth with bipolar disorder. We conducted secondary analyses of baseline data from the Treatment of Early Age Mania (TEAM) study, a randomized controlled trial of individuals aged 6-15 years (mean ± SD = 10.2 ± 2.7 years) with DSM-IV bipolar I disorder (N = 379). Sleep disorders (i.e., nightmare, sleep terror, and sleepwalking disorders) and suicide risk were assessed via the WASH-U-KSADS and the CDRS-R, respectively. We constructed uncontrolled logistic regression models as well as models controlling for trauma history, a generalized anxiety disorder (GAD) diagnosis, and depression symptoms. Participants with a current comorbid nightmare disorder versus those without were nearly twice as likely to screen positive for suicide risk in an uncontrolled model and models controlling for trauma history, a GAD diagnosis, and depression symptoms. Neither a current comorbid sleep terror disorder nor a sleepwalking disorder was significantly associated with suicide risk. This pattern of findings remained consistent for both current and lifetime sleep disorder diagnoses. Youth with bipolar I disorder and a comorbid nightmare disorder appear to be at heightened suicide risk. Implications for assessment and treatment are discussed.

Sleep biosignature of Type 2 diabetes: a case-control study.

AIM: To determine whether or not the sleep disturbances associated with Type 2 diabetes affect the structure of sleep. METHODS: We designed a case-control study in 76 patients with Type 2 diabetes and 76 control subjects without Type 2 diabetes, matched by age, gender, BMI and waist and neck circumferences. A subgroup of 32 patients with Type 2 diabetes was also matched with 64 control subjects without Type 2 diabetes according to apnoea-hypopnoea index score. Examination included an overnight full polysomnography. RESULTS: No differences in the percentage of time spent in either rapid eye movement or non-rapid eye movement sleep were observed between groups; however, patients with Type 2 diabetes had more microarousal events during sleep than control subjects [41.4 (total range 4.0-104.4) vs 20.7 (total range 1.3-94.5) events/h; P < 0.001]. These differences were mainly observed during the non-rapid eye movement sleep [7.4 (total range 0-107.2) vs 0.2 (total range 0-65.2) events/h; P < 0.001]. In addition, sleep variables related to oxygen saturation measures, such as the percentage of time spent with oxygen saturation ≤90%, were significantly greater during the rapid eye movement sleep in patients with Type 2 diabetes [20.3 (total range 0-99.2) vs. 10.5 (total range 0-94.0)%; P = 0.047]. This pattern was maintained in the subgroup of patients matched by apnoea-hypopnaea index. Finally, stepwise regression analyses showed that apnoea-hypopnoea index, the presence of Type 2 diabetes and fasting plasma glucose value were independently associated with the number of microarousals (R2 =0.667). CONCLUSIONS: Type 2 diabetes is associated with an altered sleep structure, with different effects according to rapid eye movement (increase in nocturnal hypoxia) or non-rapid eye movement (increase in sleep fragmentation) sleep.

Sexsomnia: sleep sex research and its legal implications.

"Sleep sex," also known as sexsomnia, is a sleep disorder characterized by sexual behaviors committed while asleep. There has recently been increased interest in sexsomnia due to controversies arising in legal trials that have been widely publicized in the social and public media. This article attempts to marshal the current information about sexsomnia from the forensic literature and provides an overview of sexsomnia including common features, precipitating factors, prevalence rates, diagnostic procedures, and treatment. As sexsomnia represents a condition in which sexual acts are committed without awareness or intention, this paper also reviews the development of sexsomnia as a legal defense and summarizes Canadian case law on the topic. It provides an overview of the hurdles presented to defense attorneys attempting to utilize the defense and examines popular public notions surrounding the legitimacy of sexsomnia and the possibility of malingering. We conclude that sexsomnia is a legitimate sleep disorder for which case law now exists to support its use in legal defenses based on automatism. The question of whether it is an example of "sane" or "insane" automatism remains to be determined by the courts. Regardless of whether or not sexsomnia is determined to be a mental disorder by the courts, it is now a recognized and well-described sleep disorder that can be safely treated and managed by knowledgeable clinicians.

Insomnia with physiological hyperarousal is associated with hypertension.

Previous studies have suggested that insomnia with objective short sleep duration is associated with a higher risk of hypertension, and it has been speculated that the underlying mechanism is physiological hyperarousal. In this study, we tested whether insomnia with physiological hyperarousal measured by Multiple Sleep Latency Test (MSLT), a standard test of sleepiness/alertness, is associated with increased risk of hypertension. Two hundred nineteen chronic insomniacs and 96 normal sleepers were included in this study. Chronic insomnia was defined based on standard diagnostic criteria with symptoms lasting ≥6 months. All subjects underwent 1 night in laboratory polysomnography followed by a standard MSLT. We used the median mean MSLT value (ie, >14 minutes) and the 75th percentile of mean MSLT value (ie, >17 minutes) to define hyperarousal. Hypertension was defined based either on blood pressure measures or on diagnosis treatment by a physician. After controlling for age, sex, body mass index, apnea-hypopnea index, diabetes mellitus, smoking, alcohol, and caffeine use, insomnia combined with MSLT >14 minutes increased the odds of hypertension by 300% (odds ratio=3.27; 95% confidence interval=1.20-8.96), whereas insomnia combined with MSLT >17 minutes increased even further the odds of hypertension by 400% (odds ratio=4.33; 95% confidence interval=1.48-12.68) compared with normal sleepers with MSLT ≤14 minutes. Insomnia associated with physiological hyperarousal is associated with a significant risk of hypertension. Long MSLT values may be a reliable index of the physiological hyperarousal and biological severity of chronic insomnia.

Are confusional arousals pathological?

OBJECTIVE: The objective of this study was to determine the extent that confusional arousals (CAs) are associated with mental disorders and psychotropic medications. METHODS: Cross-sectional study conducted with a representative sample of 19,136 noninstitutionalized individuals of the US general population aged 18 years or older. The study was performed using the Sleep-EVAL expert system and investigated sleeping habits; health; and sleep, mental, and medical conditions (DSM-IV-TR, ICSD-II, ICD-10). RESULTS: A total of 15.2% (95% confidence interval 14.6%-15.8%) (n=2,421) of the sample reported episodes of CAs in the previous year; 8.6% had complete or partial amnesia of the episodes and 14.8% had CAs and nocturnal wandering episodes. Eighty-four percent of CAs were associated with sleep/mental disorders or psychotropic drugs. Sleep disorders were present for 70.8% of CAs. Individuals with a circadian rhythm sleep disorder or a long sleep duration (≥9 hours) were at higher risk of CAs. Mental disorders were observed in 37.4% of CAs. The highest odds were observed in individuals with bipolar disorders or panic disorder. Use of psychotropic medication was reported by 31.3% of CAs: mainly antidepressant medications. After eliminating possible causes and associated conditions, only 0.9% of the sample had CA disorder. CONCLUSIONS: CAs are highly prevalent in the general population. They are often reported allegedly as a consequence of the treatment of sleep disorders. For the majority of subjects experiencing CAs, no medications were used, but among those who were using medications, antidepressants were most common. Sleep and/or mental disorders were important factors for CAs independent of the use of any medication.

Prevalence of urinary incontinence and lower urinary tract symptoms in school-age children.

PURPOSE: To investigate the prevalence of lower urinary tract symptoms (LUTS) and urinary incontinence (UI) in elementary school aged children in Manisa. MATERIALS AND METHODS: Dysfunctional Voiding and Incontinence Scoring System (DVIS) which was developed in Turkey is used. A total of 416 children, 216 (51.9%) male and 200 (48.1%) female were recruited in this study. RESULTS: Mean age of children was 10.35 ± 2.44 years (median10 years). Daytime UI frequency was 6.7% (28 child), nocturnal incontinence 16.6% (69 child) and combined daytime and nocturnal incontinence 4.1% (17 child). There was no statistically significant difference in the prevalence of nocturnal and or daytime UI between male and female gender. Mean DVIS score was 2.65 ± 3.95 and gender did not affect total DVIS points. The mean ages of achieving daytime bowel and bladder control were all significantly correlated with DVIS points. DVIS points were positively correlated with the history of UI of the family. Total points were increased when the father was unemployed. CONCLUSION: UI negatively influences health related quality of life of the family and child, so it is important that awareness of the UI and symptoms of lower urinary tract dysfunction.

The effect of sleep duration and quality on academical success of the elementary school children in Kayseri Turkey.

OBJECTIVE: To assess the sleeping habits of primary school children and establish link between sleeping hours and academic achievement. METHODS: The cross-sectional study was conducted between April and June 2007, involving 2422 students of 6-8th grades in 12 primary schools located in Kayseri, Turkey. A questionnaire was presented to the students on the basis of probability sampling method. Academic performance was evaluated with regard to their school grades. SPSS 20 was used for statistical analysis. RESULTS: Of the total 2422 questionnaires distributed, 1966 (81.2%) were used for further evaluation. The mean sleeping period of the students during school days was 8.86 +/- 1.10 hours. The number of students having difficulty in waking up in the morning was 940 (47.8%), while 910 (46.3%) were confused when they woke up during the night, and the 886 (45.1%) had nightmares, while 609 (31.0%) were sleepy all day long. As the sleeping period increased, the probability of a mediocre achievement in science lessons increased by 1.33 fold and poor achievement increased by 1.57 fold. Besides, the probability of a mediocre achievement in mathematics lessons increased by 1.36 fold, and poor achievement increased by 1.67 fold. For Turkish language lessons, these increases were found to be 1.40 and 1.60 respectively. Correlation analysis showed a significant negative relationship between sleeping time and successful scores in Turkish (r = -0.65, p < 0.025) and science (r = -0.061, p < 0.036) lessons. CONCLUSION: As the sleeping period increased, the academic achievement of the students was negatively affected. The academic success was low in children who felt sleepy throughout the day.

Disorders of arousal and sleep-related bruxism among Japanese adolescents: a nationwide representative survey.

OBJECTIVE: The main objective of our study was to clarify the prevalence of disorders of arousal (confusional arousals, sleepwalking, sleep terrors) and sleep-related bruxism (teeth grinding) and their associated factors among Japanese adolescents. METHODS: Our study was designed as a cross-sectional sampling survey. The targets were students attending junior and senior high schools throughout Japan. The questionnaire asked for personal data and information on lifestyle, depressive state, and sleep status including the frequency of experiencing disorders of arousal and sleep-related bruxism. RESULTS: A total of 99,416 adolescents responded. The overall response rate was 63.7%, and 98,411 questionnaires were subjected to analysis. The prevalence of disorders of arousal was 7.1% (95% confidence interval [CI], 6.9-7.3%) among boys and 7.7% (95% CI, 7.5-7.9%) among girls. The prevalence of sleep-related bruxism was 2.3% (95% CI, 2.2-2.4%) among boys and 3.0% (95% CI, 2.8-3.2%) among girls. The factors associated with disorders of arousal were the grade in school, smoking habit, alcohol consumption, naptime (min), breakfast habit, participation in club activities, sleep duration, difficulty initiating sleep, nocturnal awakening, early morning awakening, subjective sleep assessment, snoring, decrease in positive feelings, and depression (all p<.001). The factors associated with sleep-related bruxism were gender, smoking habit, nocturnal awakening, snoring, early morning awakening, decrease in positive feelings, and depressive feelings (all p<.001). CONCLUSIONS: If disorders of arousal or sleep-related bruxism are observed in an adolescent, his or her smoking habit, alcohol consumption, sleep status, and depressive state should be considered.

Arousals are frequent and associated with exacerbated blood pressure response in patients with primary hypertension.

BACKGROUND: Spontaneous arousals are relatively common during sleep, and induce hemodynamic responses. We sought to investigate the frequency and magnitude of blood pressure (BP) increases triggered by spontaneous arousals in patients with primary hypertension. METHODS: We conducted a study in which we divided 18 nonobese, sedentary adults without sleep-disordered breathing into two groups, consisting of: (i) hypertensive (HT, n = 8) patients; and (ii) normotensive (NT, n = 10) controls. The groups were matched for age and body mass index. All subjects underwent full polysomnography with simultaneous monitoring of heart rate (HR) and beat-by-beat BP. Each subject's BP and HR were analyzed immediately before BP peaks triggered by spontaneous arousals during stage 2 of nonrapid eye movement sleep. RESULTS: The total sleep time, sleep efficiency, and sleep structure in the two study groups were similar. In contrast, the number of arousals was significantly higher in the HT than in the NT group, at 25 ± 5 vs. 12 ± 3 events/h, respectively (P < 0.05). The HR of the HT and NT groups was similar before arousal (65 ± 3 bpm vs. 67 ± 3 bpm, respectively, P < 0.01) and increased significantly and similarly in the two groups upon arousal (to 79 ± 6 bpm vs. 74 ± 4 bpm, respectively, P < 0.01). Systolic and diastolic BPs were significantly higher throughout sleep in the HT than in the NT group. During spontaneous arousals, BP increased in both groups (P < 0.05). However, the magnitude of the increase in systolic BP was significantly greater in the HT than in the NT group (22 ± 3 mm Hg vs. 15 ± 3 mm Hg, P < 0.05). CONCLUSIONS: Patients with hypertension who do not have sleep-disordered breathing have an increased cardiovascular burden during sleep, which may be due to the greater number of arousals and exacerbated systolic BP response that they experience during sleep. These novel findings may have cardiovascular implications in patients with hypertension.

Disturbed dreaming and the instability of sleep: altered nonrapid eye movement sleep microstructure in individuals with frequent nightmares as revealed by the cyclic alternating pattern.

STUDY OBJECTIVES: Nightmares are disturbing mental experiences during sleep that usually result in abrupt awakenings. Frequent nightmares are associated with poor subjective sleep quality, and recent polysomnographic data suggest that nightmare sufferers exhibit impaired sleep continuity during nonrapid eye movement (NREM) sleep. Because disrupted sleep might be related to abnormal arousal processes, the goal of this study was to examine polysomnographic arousal-related activities in a group of nightmare sufferers and a healthy control group. DESIGN: Sleep microstructure analysis was carried out by scoring the cyclic alternating pattern (CAP) in NREM sleep and the arousal index in rapid eye movement (REM) sleep on the second night of the polysomnographic examination. SETTING: Hospital-based sleep research laboratory. PARTICIPANTS: There were 17 in the nightmare (NMs) group and 23 in the healthy control (CTLs) group. INTERVENTIONS: N/A. MEASUREMENTS AND RESULTS: The NMs group exhibited reduced amounts of CAP A1 subtype and increased CAP A2 and A3 subtypes, as well as longer duration of CAP A phases in comparison with CTLs. Moreover, these differences remained significant after controlling for the confounding factors of anxious and depressive symptoms. The absolute number and frequency of REM arousals did not differ significantly between the two groups. CONCLUSIONS: The results of our study indicate that NREM sleep microstructure is altered during nonsymptomatic nights of nightmares. Disrupted sleep in the NMs group seems to be related to abnormal arousal processes, specifically an imbalance in sleep-promoting and arousing mechanisms during sleep. CITATION: Simor P; Bódizs R; Horváth K; Ferri R. Disturbed dreaming and the instability of sleep: altered nonrapid eye movement sleep microstructure in individuals with frequent nightmares as revealed by the cyclic alternating pattern. SLEEP 2013;36(3):413-419.

Sleep-related groaning: prevalence and characteristics in a cohort of patients with suspected obstructive sleep apnea.

CONCLUSION: Nocturnal groaning has the same prevalence in patients referred for diagnosis of sleep-disordered breathing as among other populations referred for sleep studies. The respiratory tracings in these patients have a distinct appearance that is possible to recognize with a polygraphic recording and thereby prevent the pattern from being misdiagnosed as central apneas. OBJECTIVES: The aim of this study was first to estimate the prevalence of groaning in patients referred for diagnosis of sleep-related breathing disorders. Second, we wanted to describe the respiratory pattern in order to distinguish the patients from patients with sleep apnea. METHODS: This was a prospective study in 1004 patients, performed in the Sleep Unit in our ENT Department, during a 12 month period. RESULTS: Four patients were diagnosed with video polysomnography, and the diagnosis of nocturnal groaning was confirmed. The prevalence of groaning in our sleep laboratory was 0.4%. All the patients had a mild form of sleep-related disturbance, and all groaning episodes occurred during REM sleep. The groaning events appeared in clusters. The length of each groan varied between 4 and 38 s. The number of events in a period varied between 2 and 11, and the length of each groaning period ranged between 11 and 168 s.

Sleep disturbance in pre-school children with obstructive sleep apnoea syndrome.

STUDY OBJECTIVES: Sleep-disordered breathing in children is most prevalent in the pre-school years and has been associated with sleep fragmentation and hypoxia. We aimed to compare the sleep and spontaneous arousal characteristics of 3-5-year-old children with obstructive sleep apnoea (OSA) with that of non-snoring control children, and to further characterise the arousal responses to obstructive respiratory events. METHODS: A total of 73 children (48 male) underwent overnight polysomnography: 51 for assessment of snoring who were subsequently diagnosed with OSA (obstructive apnoea hypopnoea index (OAHI)>1 event per h) and 22 control children recruited from the community (OAHI ≤ 1 and no history of snoring). RESULTS: The OSA group had poorer sleep efficiency (p<0.05), spent a smaller proportion of their sleep period time in rapid eye movement (REM) (p<0.05), and had significantly fewer spontaneous arousals (p<0.001) compared with controls. One-quarter of the children with OSA had a sleep pressure score above the cut-off point for increased sleep pressure. In children with OSA, 62% of obstructive respiratory events terminated in a cortical arousal and 21% in a sub-cortical arousal. A significantly higher proportion of obstructive respiratory events terminated in a cortical arousal during non-REM (NREM) compared with REM (p<0.001). CONCLUSIONS: These findings suggest that in pre-school children OSA has a profound effect on sleep and arousal patterns. Given that these children are at a critical period for brain development, the impact of OSA may have more severe consequences than in older children.

Gender differences in nightmare frequency: a meta-analysis.

Many studies have reported gender differences in nightmare frequency. In order to study this difference systematically, data from 111 independent studies have been included in the meta-analysis reported here. Overall, estimated effect sizes regarding the gender difference in nightmare frequency differed significantly from zero in three age groups of healthy persons (adolescents, young adults, and middle-aged adults), whereas for children and older persons no substantial gender difference in nightmare frequency could be demonstrated. There are several candidate variables like dream recall frequency, depression, childhood trauma, and insomnia which might explain this gender difference because these variables are related to nightmare frequency and show stable gender differences themselves. Systematic research studying the effect of these variables on the gender difference in nightmare frequency, though, is still lacking. In the present study it was found that women tend to report nightmares more often than men but this gender difference was not found in children and older persons. Starting with adolescence, the gender difference narrowed with increasing age. In addition, studies with binary coded items showed a markedly smaller effect size for the gender difference in nightmare frequency compared to the studies using multiple categories in a rating scale. How nightmares were defined did not affect the gender difference. In the analyses of all studies and also in the analysis for the children alone the data source (children vs. parents) turned out to be the most influential variable on the gender difference (reporting, age). Other results are also presented. Investigating factors explaining the gender difference in nightmare frequency might be helpful in deepening the understanding regarding nightmare etiology and possibly gender differences in other mental disorders like depression or posttraumatic stress disorder.

Increased frequency of arousal parasomnias in families with nocturnal frontal lobe epilepsy: a common mechanism?

PURPOSE: Retrospective observations disclosed an overlap between parasomnias and nocturnal frontal lobe epilepsy (NFLE) not only in patients but also in their relatives, suggesting a possible common pathogenetic mechanism. This study aimed to verify whether relatives of patients with NFLE have a higher frequency of parasomnias, namely arousal disorders, and thereby shed light on the still unknown pathophysiologic mechanisms underlying NFLE. METHODS: We undertook a case-control family study in which we recruited NFLE probands and healthy controls, matched for age, sex, education, and geographic origin. At least four relatives were included for each proband and control. Each subject underwent a standardized interview, with application of the International Classification of Sleep Disorders-Revised (ICSD-R 2001) minimal criteria to diagnose the lifetime prevalence of the main parasomnias. RESULTS: Four hundred fifty-eight individuals were recruited: 33 NFLE probands, 200 relatives of probands, 31 controls, and 194 control relatives. All NFLE probands but one have sporadic NFLE. The lifetime prevalence of the following parasomnias differed in proband relatives versus control relatives: arousal disorders [odds ratio (OR) 4.7, 95% confidence interval (CI) 2.0-11.6; p < 0.001] and nightmares (OR 2.6, 95% CI 1.6-4.2; p < 0.001) were more frequent among NFLE proband relatives. In the secondary analysis comparing NFLE probands to controls, arousal disorders (OR 6.3, 95% CI 1.3-31.7; p = 0.023) and bruxism (OR 5.4, 95% CI 1.3-21.7; p = 0.017) were more frequent among NFLE probands. DISCUSSION: The higher frequency of arousal disorders in NFLE families suggests an intrinsic link between parasomnias and NFLE and an abnormal (possibly cholinergic) arousal system as a common pathophysiologic mechanism.