Journal of Sleep Research via MedWorm.com

Different sleep onset criteria at the multiple sleep latency test (MSLT): an additional marker to differentiate central nervous system (CNS) hypersomnias

Journal of Sleep Research — Tue, 09 Mar 2010 00:00:00 +0100

Excessive daytime sleepiness (EDS) has different correlates in non-rapid eye movement (NREM) [idiopathic hypersomnia (IH) without long sleep time] and REM sleep [narcolepsy without cataplexy (NwoC) and narcolepsy with cataplexy (NC)]-related hypersomnias of central origin. We analysed sleep onset characteristics at the multiple sleep latency test (MSLT) applying simultaneously two sleep onset criteria in 44 NC, seven NwoC and 16 IH consecutive patients referred for subjective EDS complaint. Sleep latency (SL) at MSLT was assessed both as the time elapsed to the occurrence of a single epoch of sleep Stage 1 NREM (SL) and of unequivocal sleep [three sleep Stage 1 NREM epochs or any other sleep stage epoch, sustained SL (SusSL)]. Idiopathic hypersomnia patients showed significantly (P < 0.000...

Sleep disturbances in asymptomatic BRCA1/2 mutation carriers: women at high risk for breast–ovarian cancer

Journal of Sleep Research — Mon, 08 Mar 2010 00:00:00 +0100

In conclusion, asymptomatic BRCA1/2 carriers experience poor sleep quality compared to non-carriers and controls. Our study design is unique in that it offers insight regarding the nature of being an asymptomatic carrier, and affords the opportunity to examine factors that may contribute to the development of insomnia in women at risk for breast[ndash]ovarian cancer. (Source: Journal of Sleep Research)

Short sleep duration and long spells of driving are associated with the occurrence of Japanese drivers' rear-end collisions and single-car accidents

Journal of Sleep Research — Mon, 08 Mar 2010 00:00:00 +0100

This study aimed to clarify that short sleep duration and long spells of driving are more associated with rear-end collisions and single-car accidents as compared with accidents of other types in cases of people who cause accidents. After removing drunken driving as a cause of accidents, 1772 parties involved in accidents were questioned. The quantities of rear-end collisions and single-car accidents were, respectively, 240 and 293. Logistic regression analysis showed that short nocturnal sleep ( (Source: Journal of Sleep Research)

Sleep-disordered breathing in children is associated with impairment of sleep stage-specific shift of cardiac autonomic modulation

Journal of Sleep Research — Mon, 08 Mar 2010 00:00:00 +0100

We examined the effects of sleep stages and sleep-disordered breathing (SDB) on autonomic modulation in 700 children. Apnea hypopnea index (AHI) during one 9 h night-time polysomnography was used to define SDB. Sleep stage-specific autonomic modulation was measured by heart rate variability (HRV) analysis of the first available 5 min RR intervals from each sleep stage. The mean [standard deviation (SD)] age was 112 (21) months (49% male and 25% non-Caucasian). The average AHI was 0.79 (SD = 1.03) h[minus]1, while 73.0%, 25.8% and 1.2% of children had AHI (Source: Journal of Sleep Research)

Validating an automated sleep spindle detection algorithm using an individualized approach.

Journal of Sleep Research — Wed, 10 Feb 2010 00:00:00 +0100

Authors: Ray LB, Fogel SM, Smith CT, Peters KR Summary The goal of the current investigation was to develop a systematic method to validate the accuracy of an automated method of sleep spindle detection that takes into consideration individual differences in spindle amplitude. The benchmarking approach used here could be employed more generally to validate automated spindle scoring from other detection algorithms. In a sample of Stage 2 sleep from 10 healthy young subjects, spindles were identified both manually and automatically. The minimum amplitude threshold used by the prana((R)) (PhiTools, Strasbourg, France) software spindle detection algorithm to identify a spindle was subject-specific and determined based upon each subject's mean peak spindle amplitude. Overall sensitivity and...

Measuring the error in sleep estimation in normal subjects and in patients with insomnia.

Journal of Sleep Research — Wed, 10 Feb 2010 00:00:00 +0100

Authors: Manconi M, Ferri R, Sagrada C, Punjabi NM, Tettamanzi E, Zucconi M, Oldani A, Castronovo V, Ferini-Strambi L Summary The aims of this study were to measure the error in sleep estimation in normal controls and subjects with primary insomnia to establish the minimum amount of sleep needed for reliable subjective estimation and to depict the distribution of the error in sleep estimation in both groups. A two-step retrospective (study 1) and prospective (study 2) validation study was carried out. Study 1 included 288 normal subjects [176 females and 112 males, mean age 58.5 years, standard deviation (SD) 7.23]. Study 2 included 159 patients (98 females and 61 males; mean age 49.1 years, SD 12.71) with primary insomnia. Participants underwent a full-night polysomnographic study, fo...

Genome-wide linkage of obstructive sleep apnoea and high-density lipoprotein cholesterol in a Filipino family: bivariate linkage analysis of obstructive sleep apnoea.

Journal of Sleep Research — Wed, 10 Feb 2010 00:00:00 +0100

Authors: Relf BL, Larkin EK, Torres CD, Baur LA, Christodoulou J, Waters KA Summary Increasing evidence supports an association between obstructive sleep apnoea (OSA) and metabolic syndrome (MeS) in both children and adults, suggesting a genetic component. However, the genetic relationship between the diseases remains unclear. We performed a bivariate linkage scan on a single Filipino family with a high prevalence of OSA and MeS to explore the genetic pathways underlying these diseases. A large rural family (n = 50, 50% adults) underwent a 10-cM genome-wide scan. Fasting blood was used to measure insulin, triglycerides, total cholesterol and high density lipoprotein (HDL) cholesterol. Attended overnight polysomnography was used to quantify the respiratory disturbance index (RDI), a mea...

Genome-wide linkage of obstructive sleep apnoea and high-density lipoprotein cholesterol in a Filipino family: bivariate linkage analysis of obstructive sleep apnoea

Journal of Sleep Research — Wed, 10 Feb 2010 00:00:00 +0100

Increasing evidence supports an association between obstructive sleep apnoea (OSA) and metabolic syndrome (MeS) in both children and adults, suggesting a genetic component. However, the genetic relationship between the diseases remains unclear. We performed a bivariate linkage scan on a single Filipino family with a high prevalence of OSA and MeS to explore the genetic pathways underlying these diseases. A large rural family (n = 50, 50% adults) underwent a 10-cM genome-wide scan. Fasting blood was used to measure insulin, triglycerides, total cholesterol and high density lipoprotein (HDL) cholesterol. Attended overnight polysomnography was used to quantify the respiratory disturbance index (RDI), a measure of sleep apnoea. Body mass index z-scores and insulin resistance scores were calcul...

Measuring the error in sleep estimation in normal subjects and in patients with insomnia

Journal of Sleep Research — Wed, 10 Feb 2010 00:00:00 +0100

The aims of this study were to measure the error in sleep estimation in normal controls and subjects with primary insomnia to establish the minimum amount of sleep needed for reliable subjective estimation and to depict the distribution of the error in sleep estimation in both groups. A two-step retrospective (study 1) and prospective (study 2) validation study was carried out. Study 1 included 288 normal subjects [176 females and 112 males, mean age 58.5 years, standard deviation (SD) 7.23]. Study 2 included 159 patients (98 females and 61 males; mean age 49.1 years, SD 12.71) with primary insomnia. Participants underwent a full-night polysomnographic study, followed by a morning assessment of subjective sleep parameters. A misperception index (MI) was computed using the following formula...

Validating an automated sleep spindle detection algorithm using an individualized approach

Journal of Sleep Research — Wed, 10 Feb 2010 00:00:00 +0100

The goal of the current investigation was to develop a systematic method to validate the accuracy of an automated method of sleep spindle detection that takes into consideration individual differences in spindle amplitude. The benchmarking approach used here could be employed more generally to validate automated spindle scoring from other detection algorithms. In a sample of Stage 2 sleep from 10 healthy young subjects, spindles were identified both manually and automatically. The minimum amplitude threshold used by the prana® (PhiTools, Strasbourg, France) software spindle detection algorithm to identify a spindle was subject-specific and determined based upon each subject's mean peak spindle amplitude. Overall sensitivity and specificity values were 98.96 and 88.49%, respectively, when ...

Sleep history affects task acquisition during subsequent sleep restriction and recovery

Journal of Sleep Research — Tue, 29 Dec 2009 00:00:00 +0100

The aim of the present study was to examine if sleep amount prior to sleep restriction mediated subsequent task acquisition on serial addition/subtraction and reaction time (RT) sub-tasks of the Automated Neuropsychological Assessment Metric. Eleven males and 13 females [mean (SD) age = 25 (6.5) years] were assigned to either an Extended [10 h time in bed (TIB)] (n = 12) or Habitual [Mean (SD) = 7.09 (0.7)] (n = 12) sleep group for 1 week followed by one baseline night, seven sleep restriction nights (3 h TIB) and five recovery nights (8 h TIB). Throughout baseline, restriction and recovery, mathematical and serial RT tasks were administered hourly each day (08:00[ndash]18:00 h). Math and serial RT throughput for each task (speed × accuracy product) was analysed using a mixed-model anova ...

Reaction of sleepiness indicators to partial sleep deprivation, time of day and time on task in a driving simulator - the DROWSI project.

Journal of Sleep Research — Mon, 28 Dec 2009 00:00:00 +0100

Authors: Akerstedt T, Ingre M, Kecklund G, Anund A, Sandberg D, Wahde M, Philip P, Kronberg P Summary Studies of driving and sleepiness indicators have mainly focused on prior sleep reduction. The present study sought to identify sleepiness indicators responsive to several potential regulators of sleepiness: sleep loss, time of day (TOD) and time on task (TOT) during simulator driving. Thirteen subjects drove a high-fidelity moving base simulator in six 1-h sessions across a 24-h period, after normal sleep duration (8 h) and after partial sleep deprivation (PSD; 4 h). The results showed clear main effects of TOD (night) and TOT but not for PSD, although the latter strongly interacted with TOD. The most sensitive variable was subjective sleepiness, the standard deviation of lateral posi...

Sleep history affects task acquisition during subsequent sleep restriction and recovery.

Journal of Sleep Research — Mon, 28 Dec 2009 00:00:00 +0100

Authors: Rupp TL, Wesensten NJ, Balkin TJ Summary The aim of the present study was to examine if sleep amount prior to sleep restriction mediated subsequent task acquisition on serial addition/subtraction and reaction time (RT) sub-tasks of the Automated Neuropsychological Assessment Metric. Eleven males and 13 females [mean (SD) age = 25 (6.5) years] were assigned to either an Extended [10 h time in bed (TIB)] (n = 12) or Habitual [Mean (SD) = 7.09 (0.7)] (n = 12) sleep group for 1 week followed by one baseline night, seven sleep restriction nights (3 h TIB) and five recovery nights (8 h TIB). Throughout baseline, restriction and recovery, mathematical and serial RT tasks were administered hourly each day (08:00-18:00 h). Math and serial RT throughput for each task (speed x accuracy p...

Sleep deprivation impairs spatial working memory and reduces hippocampal AMPA receptor phosphorylation.

Journal of Sleep Research — Mon, 28 Dec 2009 00:00:00 +0100

In conclusion, a relatively short SD during the normal resting phase may affect spatial working memory in mice by reducing hippocampal AMPA receptor function through a change in AKAP150 levels. Together, these findings provide further insight into the possible mechanism of SD-induced hippocampal dysfunction and memory impairment. PMID: 20050994 [PubMed - as supplied by publisher] (Source: Journal of Sleep Research)

The sleep of children with attention deficit hyperactivity disorder on and off methylphenidate: a matched case-control study.

Journal of Sleep Research — Mon, 28 Dec 2009 00:00:00 +0100

Authors: Galland BC, Tripp EG, Taylor BJ Summary In the present study, we assessed the effects of regular use of methylphenidate medication in children diagnosed with attention deficit hyperactivity disorder (ADHD) on sleep timing, duration and sleep architecture. Twenty-seven children aged 6-12 years meeting diagnostic criteria for Diagnostic and Statistical Manual version IV ADHD and 27 control children matched for age (+/-3 months) and gender. Two nights of standard polysomnographic (PSG) recordings were conducted. ADHD children were allocated randomly to an on- or 48 h off-methylphenidate protocol for first or second recordings. Control children's recordings were matched for night, but no medication was used. Mixed modelling was employed in the analyses so that the full data set wa...

Perception of experimental pain is reduced after provoked waking from rapid eye movement sleep.

Journal of Sleep Research — Mon, 28 Dec 2009 00:00:00 +0100

Authors: Daya VG, Bentley AJ Summary Patients with chronic pain often complain of pain when they wake at night, but the accuracy of their perception of the pain after waking at night is unknown. While cognitive functions are reduced for a short time after waking from sleep, a situation known as sleep inertia, it is unclear how sleep inertia may affect the perception of pain. We investigated the effects of sleep inertia on the perception of experimentally induced pain. Fourteen male volunteers were exposed to a randomized thermal heat stimulus of 43.1 degrees C 'hot' and 46.5 degrees C 'hurting' during provoked waking from Stage 2 sleep, slow wave sleep and rapid eye movement (REM) sleep. Subjects rated their pain on awakening on a Visual Analogue Scale at 30 s after awakening and each ...

Cardiorespiratory response to spontaneous cortical arousals during stage 2 and rapid eye movement sleep in healthy children.

Journal of Sleep Research — Mon, 28 Dec 2009 00:00:00 +0100

In conclusion, cortical arousals in children are associated with an increase in breathing rate and significant heart rate accelerations, which typically precede the cortical arousal onset. PMID: 20050997 [PubMed - as supplied by publisher] (Source: Journal of Sleep Research)

Reaction of sleepiness indicators to partial sleep deprivation, time of day and time on task in a driving simulator – the DROWSI project

Journal of Sleep Research — Mon, 28 Dec 2009 00:00:00 +0100

Studies of driving and sleepiness indicators have mainly focused on prior sleep reduction. The present study sought to identify sleepiness indicators responsive to several potential regulators of sleepiness: sleep loss, time of day (TOD) and time on task (TOT) during simulator driving. Thirteen subjects drove a high-fidelity moving base simulator in six 1-h sessions across a 24-h period, after normal sleep duration (8 h) and after partial sleep deprivation (PSD; 4 h). The results showed clear main effects of TOD (night) and TOT but not for PSD, although the latter strongly interacted with TOD. The most sensitive variable was subjective sleepiness, the standard deviation of lateral position (SDLAT) and measures of eye closure [duration, speed (slow), amplitude (low)]. Measures of electroenc...

Perception of experimental pain is reduced after provoked waking from rapid eye movement sleep

Journal of Sleep Research — Mon, 28 Dec 2009 00:00:00 +0100

Patients with chronic pain often complain of pain when they wake at night, but the accuracy of their perception of the pain after waking at night is unknown. While cognitive functions are reduced for a short time after waking from sleep, a situation known as sleep inertia, it is unclear how sleep inertia may affect the perception of pain. We investigated the effects of sleep inertia on the perception of experimentally induced pain. Fourteen male volunteers were exposed to a randomized thermal heat stimulus of 43.1 °C 'hot' and 46.5 °C 'hurting' during provoked waking from Stage 2 sleep, slow wave sleep and rapid eye movement (REM) sleep. Subjects rated their pain on awakening on a Visual Analogue Scale at 30 s after awakening and each minute thereafter for 5 min. We found no change in pa...

The sleep of children with attention deficit hyperactivity disorder on and off methylphenidate: a matched case–control study

Journal of Sleep Research — Mon, 28 Dec 2009 00:00:00 +0100

In the present study, we assessed the effects of regular use of methylphenidate medication in children diagnosed with attention deficit hyperactivity disorder (ADHD) on sleep timing, duration and sleep architecture. Twenty-seven children aged 6[ndash]12 years meeting diagnostic criteria for Diagnostic and Statistical Manual version IV ADHD and 27 control children matched for age (±3 months) and gender. Two nights of standard polysomnographic (PSG) recordings were conducted. ADHD children were allocated randomly to an on- or 48 h off-methylphenidate protocol for first or second recordings. Control children's recordings were matched for night, but no medication was used. Mixed modelling was employed in the analyses so that the full data set was used to determine the degree of medication eff...

Sleep deprivation impairs spatial working memory and reduces hippocampal AMPA receptor phosphorylation

Journal of Sleep Research — Mon, 28 Dec 2009 00:00:00 +0100

Cardiorespiratory response to spontaneous cortical arousals during stage 2 and rapid eye movement sleep in healthy children

Journal of Sleep Research — Mon, 28 Dec 2009 00:00:00 +0100

Catastrophizing and symptoms of sleep disturbances in children

Journal of Sleep Research — Thu, 17 Dec 2009 00:00:00 +0100

This study aimed to (1) examine whether children catastrophize about the consequences of not sleeping; (2) define the topics that children catastrophize about; (3) assess whether there is a link between catastrophizing and sleep disturbance in children; and (4) examine whether an association between catastrophizing and sleep in children is mediated by anxiety and depression symptoms. Children completed the sleep self-report and a catastrophizing interview. Testing took place in two inner-city schools in London, UK and participants comprised 123 children aged between 8 and 10 years (49% male). Thirty-four (28%) participants reported concerns in response to the catastrophizing questionnaire. The main topics being catastrophized were concerns about sleep, physiological issues and one's own em...

Catastrophizing and symptoms of sleep disturbances in children.

Journal of Sleep Research — Wed, 16 Dec 2009 00:00:00 +0100

Effect of sleep deprivation on multi-unit discharge activity of basal forebrain.

Journal of Sleep Research — Wed, 16 Dec 2009 00:00:00 +0100

Authors: Kostin A, Stenberg D, Porkka-Heiskanen T Summary The basal forebrain (BF) is an important wakefulness/arousal-promoting structure involved in homeostatic responses to sleep deprivation (SD). However, the effects of SD and subsequent sleep recovery on the BF discharge have not been investigated. Multi-unit BF activity was recorded on freely moving rats during 8 h of baseline (BL) and, on the following day, during 4 h of SD by gentle handling followed by 4 h of recovery. The effect of SD on the waking discharge was evaluated during the last 10 min of each hour when attentive waking was induced. The wakefulness level was defined based on the ratio between theta and delta electroencephalogram (EEG) powers, and epochs with ratios >/=1 but <2 (T/D-1) and >/=2 but <4 (T/D...

The activation of the inflammatory cytokines in overweight patients with mild obstructive sleep apnoea.

Journal of Sleep Research — Wed, 16 Dec 2009 00:00:00 +0100

Authors: Sahlman J, Miettinen K, Peuhkurinen K, Seppä J, Peltonen M, Herder C, Punnonen K, Vanninen E, Gylling H, Partinen M, Uusitupa M, Tuomilehto H, Summary It is widely accepted that obstructive sleep apnoea (OSA) is linked with cardiovascular diseases. The relationship is complex and remains still poorly understood. The presence of chronic systemic inflammation has been connected with pathogenesis of both OSA and cardiovascular diseases. While atherogenesis is believed to be a process of many years, little is known about the potential impact of the largest OSA subgroup, mild OSA, on the development of cardiovascular diseases. The aim of the present study was to assess whether untreated mild OSA is associated with an activation of inflammatory cytokine system. The adult study...

The activation of the inflammatory cytokines in overweight patients with mild obstructive sleep apnoea

Journal of Sleep Research — Wed, 16 Dec 2009 00:00:00 +0100

It is widely accepted that obstructive sleep apnoea (OSA) is linked with cardiovascular diseases. The relationship is complex and remains still poorly understood. The presence of chronic systemic inflammation has been connected with pathogenesis of both OSA and cardiovascular diseases. While atherogenesis is believed to be a process of many years, little is known about the potential impact of the largest OSA subgroup, mild OSA, on the development of cardiovascular diseases. The aim of the present study was to assess whether untreated mild OSA is associated with an activation of inflammatory cytokine system. The adult study population consisted of two groups: 84 patients with mild OSA [apnoea[ndash]hypopnoea index (AHI) 5[ndash]15 h[minus]1] and 40 controls (AHI (Source: Journal of Sleep Re...

Effect of sleep deprivation on multi-unit discharge activity of basal forebrain

Journal of Sleep Research — Wed, 16 Dec 2009 00:00:00 +0100

The basal forebrain (BF) is an important wakefulness/arousal-promoting structure involved in homeostatic responses to sleep deprivation (SD). However, the effects of SD and subsequent sleep recovery on the BF discharge have not been investigated. Multi-unit BF activity was recorded on freely moving rats during 8 h of baseline (BL) and, on the following day, during 4 h of SD by gentle handling followed by 4 h of recovery. The effect of SD on the waking discharge was evaluated during the last 10 min of each hour when attentive waking was induced. The wakefulness level was defined based on the ratio between theta and delta electroencephalogram (EEG) powers, and epochs with ratios [ge]1 but (Source: Journal of Sleep Research)

Self-reported sleep duration - what does it mean?

Journal of Sleep Research — Sun, 29 Nov 2009 17:16:05 +0100

Authors: Lavie P PMID: 19941591 [PubMed - as supplied by publisher] (Source: Journal of Sleep Research)

A cohort study of the prevalence of sleep problems in adults with intellectual disabilities

Journal of Sleep Research — Thu, 12 Nov 2009 00:00:00 +0100

This study aims to determine the prevalence and associations of sleep problems in the adult population with ID. The 4-week period prevalence of sleep problems was determined in a cross-sectional study of all adults with ID in a defined geographical area. Sleep problems were identified using the Psychiatric Assessment Scale for Adults with Developmental Disabilities (PAS-ADD) checklist and categorized as initial insomnia, early morning wakening and broken sleep. A fourth, composite, variable of significant sleep problem was also derived. Of the 1023 adults with ID who participated, 9.2% had experienced a significant sleep problem, during the 1-month period. Individuals with a significant sleep problem are more likely to have mental ill-health [odds ratio (OR) = 5.53, 95% confidence interval...

Sleep classification according to AASM and Rechtschaffen and Kales: effects on sleep scoring parameters of children and adolescents.

Journal of Sleep Research — Wed, 11 Nov 2009 00:00:00 +0100

Authors: Novelli L, Ferri R, Bruni O Summary Recently, the new American Academy of Sleep Medicine (AASM) rules and the old Rechtschaffen and Kales (R&K) criteria for sleep scoring have been shown to produce significantly different results in adults. The aim of this study was to describe in detail such differences in a group of normal children. Polysomnographic recordings from 45 healthy children (18 females and 27 males) aged between 3 and 16 years were scored following both systems and the results compared. Several significant differences between the two scoring systems were found: N1 (AASM) was significantly higher than S1 (R&K) while Stages N2 and R (AASM) were significantly smaller than S2 and rapid eye movement (R&K). The Kendall Tau correlation coefficient revealed a ...

The incidence and temporal patterning of insomnia: a pilot study.

Journal of Sleep Research — Wed, 11 Nov 2009 00:00:00 +0100

Authors: Perlis ML, Swinkels CM, Gehrman PR, Pigeon WR, Matteson-Rusby SE, Jungquist CR Summary To date very little research has been conducted on night-to-night variability in the incidence of insomnia. It is unclear from prior research whether subjects with primary insomnia (PI) exhibit good sleep (or better than average sleep) on some interval basis. In the present study, pilot data are provided on: (1) the frequency with which 'good sleep' occurs in subjects with PI; and (2) whether these events occur in a non-random manner. Ten subjects with PI participated in this 'naturalistic' study. All subjects completed daily sleep diaries for a minimum of 20 days. None of the subjects received treatment for their insomnia during the monitoring period. The night-to-night data were evaluated ...

Plasma adiponectin level and sleep structures in children with Prader-Willi syndrome.

Journal of Sleep Research — Wed, 11 Nov 2009 00:00:00 +0100

Authors: Joo EY, Hong SB, Sohn YB, Kwak MJ, Kim SJ, Choi YO, Kim SW, Paik KH, Jin DK Summary Adiponectin, an adipose tissue-derived hormone, has been negatively related to obstructive sleep apnea syndrome. Besides sleep apnea, children with Prader-Willi syndrome (PWS) may have excessive daytime sleepiness and rapid eye movement (REM) sleep abnormality. The aim of this study is to determine whether changes in sleep structures are related to plasma adiponectin levels in PWS. Correlations between adiponectin level and sleep variables were analyzed in 28 children with PWS and 18 controls. Overnight polysomnography was performed. The fasting plasma adiponectin levels were higher in the children with PWS than in the controls (P = 0.0006). In the PWS, Epworth sleepiness scale was significantl...

A cohort study of the prevalence of sleep problems in adults with intellectual disabilities.

Journal of Sleep Research — Wed, 11 Nov 2009 00:00:00 +0100

Plasma adiponectin level and sleep structures in children with Prader–Willi syndrome

Journal of Sleep Research — Wed, 11 Nov 2009 00:00:00 +0100

Adiponectin, an adipose tissue-derived hormone, has been negatively related to obstructive sleep apnea syndrome. Besides sleep apnea, children with Prader[ndash]Willi syndrome (PWS) may have excessive daytime sleepiness and rapid eye movement (REM) sleep abnormality. The aim of this study is to determine whether changes in sleep structures are related to plasma adiponectin levels in PWS. Correlations between adiponectin level and sleep variables were analyzed in 28 children with PWS and 18 controls. Overnight polysomnography was performed. The fasting plasma adiponectin levels were higher in the children with PWS than in the controls (P = 0.0006). In the PWS, Epworth sleepiness scale was significantly higher (P = 0.002); sleep latency (P = 0.003) and REM latency (P = 0.001) were significan...

The incidence and temporal patterning of insomnia: a pilot study

Journal of Sleep Research — Wed, 11 Nov 2009 00:00:00 +0100

To date very little research has been conducted on night-to-night variability in the incidence of insomnia. It is unclear from prior research whether subjects with primary insomnia (PI) exhibit good sleep (or better than average sleep) on some interval basis. In the present study, pilot data are provided on: (1) the frequency with which 'good sleep' occurs in subjects with PI; and (2) whether these events occur in a non-random manner. Ten subjects with PI participated in this 'naturalistic' study. All subjects completed daily sleep diaries for a minimum of 20 days. None of the subjects received treatment for their insomnia during the monitoring period. The night-to-night data were evaluated by typing each night's sleep as 'Good' or 'Bad', and then by determining the number of bad nights th...

Sleep classification according to AASM and Rechtschaffen and Kales: effects on sleep scoring parameters of children and adolescents

Journal of Sleep Research — Wed, 11 Nov 2009 00:00:00 +0100

Recently, the new American Academy of Sleep Medicine (AASM) rules and the old Rechtschaffen and Kales (R&K) criteria for sleep scoring have been shown to produce significantly different results in adults. The aim of this study was to describe in detail such differences in a group of normal children. Polysomnographic recordings from 45 healthy children (18 females and 27 males) aged between 3 and 16 years were scored following both systems and the results compared. Several significant differences between the two scoring systems were found: N1 (AASM) was significantly higher than S1 (R&K) while Stages N2 and R (AASM) were significantly smaller than S2 and rapid eye movement (R&K). The Kendall [Tau] correlation coefficient revealed a relatively low concordance between the two systems for the ...

Delayed blood pressure recovery after head-up tilting during sleep in preterm infants

Journal of Sleep Research — Thu, 05 Nov 2009 00:00:00 +0100

Dramatic changes in cardiovascular control occur in sleep during infancy, when sleep time is at a lifetime maximum. In infants born preterm there are significant cardiovascular complications later in life, and also an increased risk for sudden infant death syndrome (SIDS), possibly a result of inadequate compensation to a cardiorespiratory challenge in sleep. We aimed to examine the consequences of preterm birth on heart rate (HR) and blood pressure (BP) responses to head-up tilting (HUT) during sleep in infants. Preterm (n = 25) and term (n = 20) infants were studied using daytime polysomnography at 2[ndash]4 weeks', 2[ndash]3 months' and 5[ndash]6 months' term-corrected age (CA). BP was recorded using a photoplethysmographic cuff (Finometer[trade]); 15° HUTs were performed during both q...

Applying the quarter-hour rule: can people with insomnia accurately estimate 15-min periods during the sleep-onset phase?

Journal of Sleep Research — Wed, 04 Nov 2009 00:00:00 +0100

This study expands upon previous research with the aim of identifying whether people with insomnia can accurately perceive a 15-min interval during the sleep-onset period, and therefore successfully implements the QHR. A mixed models anova design was applied with between-participants factor of group (insomnia versus good sleepers) and within-participants factor of context (night versus day). Results indicated no differences between groups and contexts on time estimation tasks. This was despite an increase in arousal in the night context for both groups, and tentative support for the impact of arousal in inducing underestimations of time. These results provide promising support for the successful application of the QHR in people with insomnia. The results are discussed in terms of whether t...

Delayed blood pressure recovery after head-up tilting during sleep in preterm infants.

Journal of Sleep Research — Wed, 04 Nov 2009 00:00:00 +0100

Authors: Witcombe NB, Yiallourou SR, Walker AM, Horne RS Summary Dramatic changes in cardiovascular control occur in sleep during infancy, when sleep time is at a lifetime maximum. In infants born preterm there are significant cardiovascular complications later in life, and also an increased risk for sudden infant death syndrome (SIDS), possibly a result of inadequate compensation to a cardiorespiratory challenge in sleep. We aimed to examine the consequences of preterm birth on heart rate (HR) and blood pressure (BP) responses to head-up tilting (HUT) during sleep in infants. Preterm (n = 25) and term (n = 20) infants were studied using daytime polysomnography at 2-4 weeks', 2-3 months' and 5-6 months' term-corrected age (CA). BP was recorded using a photoplethysmographic cuff (Finome...

Priming affects poor sleepers but not normal sleepers on an Insomnia Ambiguity Task.

Journal of Sleep Research — Wed, 04 Nov 2009 00:00:00 +0100

Authors: Ellis J, Gardani M, Hogh H Summary With increasing importance being placed on the role of cognitive biases as a maintaining factor in insomnia, the influence of order effects on interpretative responses should be examined and subsequently accounted for. The aim of the present study was to examine whether asking participants about their sleep experiences, prior to testing for a perceptual bias, affects responses on a sleep-related ambiguity task. One hundred and seventeen undergraduate students, blind to the aims of the experiment, were issued either the Dysfunctional Beliefs and Attitudes to Sleep scale (DBAS-10) and Insomnia Severity Index (ISI) before, or following, completion of an Insomnia Ambiguity Task (IAT). As expected, a multivariate analysis of variance showed that t...

Heat-shock protein 70: expression in monocytes of patients with sleep apnoea and association with oxidative stress and tumour necrosis factor-alpha.

Journal of Sleep Research — Wed, 04 Nov 2009 00:00:00 +0100

In conclusion, basal HSP70 overexpression that is a protective mechanism indicative of disease-associated stress was significantly higher in patients with OSA and was correlated with oxidative stress. On the other hand, in response to a defined heat-stress treatment, the induction of HSP70 was lower in patients with OSA, indicative of a possible maladaptive response to an acute stress. Correlations with oxidative stress and TNF-alpha further support this conclusion. PMID: 19895425 [PubMed - as supplied by publisher] (Source: Journal of Sleep Research)

Applying the quarter-hour rule: can people with insomnia accurately estimate 15-min periods during the sleep-onset phase?

Journal of Sleep Research — Wed, 04 Nov 2009 00:00:00 +0100

Heat-shock protein 70: expression in monocytes of patients with sleep apnoea and association with oxidative stress and tumour necrosis factor-α

Journal of Sleep Research — Wed, 04 Nov 2009 00:00:00 +0100

In conclusion, basal HSP70 overexpression that is a protective mechanism indicative of disease-associated stress was significantly higher in patients with OSA and was correlated with oxidative stress. On the other hand, in response to a defined heat-stress treatment, the induction of HSP70 was lower in patients with OSA, indicative of a possible maladaptive response to an acute stress. Correlations with oxidative stress and TNF-[alpha] further support this conclusion. (Source: Journal of Sleep Research)

Priming affects poor sleepers but not normal sleepers on an Insomnia Ambiguity Task

Journal of Sleep Research — Wed, 04 Nov 2009 00:00:00 +0100

With increasing importance being placed on the role of cognitive biases as a maintaining factor in insomnia, the influence of order effects on interpretative responses should be examined and subsequently accounted for. The aim of the present study was to examine whether asking participants about their sleep experiences, prior to testing for a perceptual bias, affects responses on a sleep-related ambiguity task. One hundred and seventeen undergraduate students, blind to the aims of the experiment, were issued either the Dysfunctional Beliefs and Attitudes to Sleep scale (DBAS-10) and Insomnia Severity Index (ISI) before, or following, completion of an Insomnia Ambiguity Task (IAT). As expected, a multivariate analysis of variance showed that the order in which participants completed the tas...

Differential effects of waking from non-rapid eye movement versus rapid eye movement sleep on cardiovascular activity.

Journal of Sleep Research — Wed, 28 Oct 2009 00:00:00 +0100

This study tested the hypothesis that the increase in sympathetic dominance and the surge in BP were greater when waking spontaneously from Stage 2 sleep compared with waking from rapid eye movement (REM) sleep. Twenty healthy young adults had overnight polysomnography, including electrocardiogram measurements. Spectral analysis of heart rate variability (HRV) was conducted on 2-min blocks of stable data selected from the last 30 min of sleep and during 30 min of resting wakefulness (supine) immediately following sleep. Outputs included absolute low frequency (LF) and high frequency (HF) power, the LF/HF ratio, heart rate (HR) and BP. To investigate the effect of waking from Stage 2 or REM sleep on HRV and BP responses, two-way analyses of variance (anovas) (Stage 2 versus REM) with repeat...

Endogenous ouabain-like compounds in locus coeruleus modulate rapid eye movement sleep in rats.

Journal of Sleep Research — Wed, 28 Oct 2009 00:00:00 +0100

Authors: Jaiswal MK, Dvela M, Lichtstein D, Mallick BN Summary Although the detailed mechanism of spontaneous generation and regulation of rapid eye movement sleep (REMS) is yet unknown, it has been reported that noradrenergic REM-OFF neurons in the locus coeruleus (LC) cease firing during REMS and, if they are kept active, REMS is significantly reduced. On the other hand, the activity as well as expression of Na-K ATPase has been shown to increase in the LC following REMS deprivation. Ouabain is a specific inhibitor of Na-K ATPase, and endogenous ouabain-like compounds are present in the brain. These findings led us to propose that a decrease in the level of ouabain-like compounds spontaneously available in and around the LC would stimulate and increase the REM-OFF neuronal activities...

The effects of sleep and sleep deprivation on task-switching performance.

Journal of Sleep Research — Wed, 28 Oct 2009 00:00:00 +0100

In this study, we investigated whether SD selectively affects specific components of the executive control processes involved in task-switching performance. Two different tasks are performed in rapid and random succession in this procedure, so that the to-be-executed task may change from one trial to the next (switch trial), or may be repeated (repetition trial). Task-switches are usually slower than task repetitions, giving way to the 'switch cost'. One hundred and eight university students were assigned randomly to the sleep (S) or the SD group. Each of them was tested on a task-switching paradigm before and after an experimental night (S or SD), and after one recovery night. SD impaired both task-switching accuracy and speed. A higher proportion of errors and increased switch costs afte...

The effects of sleep and sleep deprivation on task-switching performance

Journal of Sleep Research — Wed, 28 Oct 2009 00:00:00 +0100

Endogenous ouabain-like compounds in locus coeruleus modulate rapid eye movement sleep in rats

Journal of Sleep Research — Wed, 28 Oct 2009 00:00:00 +0100

Although the detailed mechanism of spontaneous generation and regulation of rapid eye movement sleep (REMS) is yet unknown, it has been reported that noradrenergic REM-OFF neurons in the locus coeruleus (LC) cease firing during REMS and, if they are kept active, REMS is significantly reduced. On the other hand, the activity as well as expression of Na-K ATPase has been shown to increase in the LC following REMS deprivation. Ouabain is a specific inhibitor of Na-K ATPase, and endogenous ouabain-like compounds are present in the brain. These findings led us to propose that a decrease in the level of ouabain-like compounds spontaneously available in and around the LC would stimulate and increase the REM-OFF neuronal activities in this region and thus would reduce REMS. To test this hypothesis...

Differential effects of waking from non-rapid eye movement versus rapid eye movement sleep on cardiovascular activity

Journal of Sleep Research — Wed, 28 Oct 2009 00:00:00 +0100

The effects of sleep deprivation in humans: topographical electroencephalogram changes in non-rapid eye movement (NREM) sleep versus REM sleep

Journal of Sleep Research — Wed, 21 Oct 2009 23:00:00 +0100

Studies on homeostatic aspects of sleep regulation have been focussed upon non-rapid eye movement (NREM) sleep, and direct comparisons with regional changes in rapid eye movement (REM) sleep are sparse. To this end, evaluation of electroencephalogram (EEG) changes in recovery sleep after extended waking is the classical approach for increasing homeostatic need. Here, we studied a large sample of 40 healthy subjects, considering a full-scalp EEG topography during baseline (BSL) and recovery sleep following 40 h of wakefulness (REC). In NREM sleep, the statistical maps of REC versus BSL differences revealed significant fronto-central increases of power from 0.5 to 11 Hz and decreases from 13 to 15 Hz. In REM sleep, REC versus BSL differences pointed to significant fronto-central increases in...

Slow oscillations in human non-rapid eye movement sleep electroencephalogram: effects of increased sleep pressure.

Journal of Sleep Research — Tue, 20 Oct 2009 23:00:00 +0100

This study does not question slow-wave activity as a marker of sleep homeostasis, as the observed changes occurred within the same frequency range. PMID: 19845847 [PubMed - as supplied by publisher] (Source: Journal of Sleep Research)

Involvement of sympathetic function in the sleep-related change of gastric myoelectrical activity in rats.

Journal of Sleep Research — Tue, 20 Oct 2009 23:00:00 +0100

Authors: Huang YM, Yang CC, Lai CJ, Kuo TB Summary The gastric myoelectrical activity (GMA) fluctuates across sleep-wake states as a result of modulation by the brain-gut axis. The role of the autonomic nervous system in this phenomenon, however, was not elucidated fully. Through simultaneous recording and subsequent continuous power spectral analysis of electroencephalogram, electromyogram, electrocardiogram and electrogastromyogram (EGMG) in 16 freely moving Wistar rats, the sleep-wake states of the animals were defined and indices of cardiac autonomic regulation and GMA were calculated. We found that both cardiac autonomic regulation and GMA fluctuated through sleep-wake cycles. Correlation analysis further revealed significant correlations between EGMG power and each of the R-R int...

The effects of sleep deprivation in humans: topographical electroencephalogram changes in non-rapid eye movement (NREM) sleep versus REM sleep.

Journal of Sleep Research — Tue, 20 Oct 2009 23:00:00 +0100

In conclusion, REM sleep and NREM sleep seem to share some homeostatic mechanisms in response to sleep deprivation, as indicated mainly by the similar direction and topography of changes in low-frequency activity. PMID: 19845849 [PubMed - as supplied by publisher] (Source: Journal of Sleep Research)

Involvement of sympathetic function in the sleep-related change of gastric myoelectrical activity in rats

Journal of Sleep Research — Tue, 20 Oct 2009 23:00:00 +0100

The gastric myoelectrical activity (GMA) fluctuates across sleep[ndash]wake states as a result of modulation by the brain[ndash]gut axis. The role of the autonomic nervous system in this phenomenon, however, was not elucidated fully. Through simultaneous recording and subsequent continuous power spectral analysis of electroencephalogram, electromyogram, electrocardiogram and electrogastromyogram (EGMG) in 16 freely moving Wistar rats, the sleep[ndash]wake states of the animals were defined and indices of cardiac autonomic regulation and GMA were calculated. We found that both cardiac autonomic regulation and GMA fluctuated through sleep[ndash]wake cycles. Correlation analysis further revealed significant correlations between EGMG power and each of the R[ndash]R interval, high-frequency pow...

Slow oscillations in human non-rapid eye movement sleep electroencephalogram: effects of increased sleep pressure

Journal of Sleep Research — Tue, 20 Oct 2009 23:00:00 +0100

Slow oscillations ( (Source: Journal of Sleep Research)

Daytime sleepiness, psychomotor performance, waking EEG spectra and evoked potentials in women with severe premenstrual syndrome.

Journal of Sleep Research — Tue, 13 Oct 2009 23:00:00 +0100

Authors: Baker FC, Colrain IM Summary We assessed daytime sleepiness using objective and subjective measures in women with severe premenstrual syndrome (PMS) compared with women without significant premenstrual symptoms. Nine women with severe PMS and eight controls (aged 18-40 years) completed a laboratory-based daytime protocol including the maintenance of wakefulness test (MWT), psychomotor vigilance task (PVT), quantitative waking electroencephalogram (EEG), auditory and visual event-related potentials (ERPs), and sleepiness and mood scales during the mid-follicular and late-luteal (premenstrual) phases of the menstrual cycle. In association with increased perceived sleepiness, fatigue and other premenstrual symptoms in the late-luteal phase, women with PMS performed more poorly on...

Sleep disturbances as a predictor of occupational injuries among public sector workers.

Journal of Sleep Research — Tue, 13 Oct 2009 23:00:00 +0100

This study suggests that sleep disturbances are a significant predictor of occupational injuries even after accounting for a range of covariates. PMID: 19840241 [PubMed - as supplied by publisher] (Source: Journal of Sleep Research)

Sleep and physical growth in infants during the first 6 months.

Journal of Sleep Research — Tue, 13 Oct 2009 23:00:00 +0100

Authors: Tikotzky L, de Marcas G, Har-Toov J, Dollberg S, Bar-Haim Y, Sadeh A Summary The aim of this study was to explore the relationships between infant sleep patterns and infant physical growth (weight for length ratio) using both objective and subjective sleep measures. Ninety-six first-born, healthy 6-month-old infants and their parents participated in the study. Infant sleep was assessed by actigraphy for four consecutive nights and by the Brief Infant Sleep Questionnaire (BISQ). In addition, parents were asked to complete background and developmental questionnaires. Questions about feeding methods were included in the developmental questionnaire. Infants' weight and length were assessed during a standard checkup at the infant-care clinic when the infants were 6 months old. Sign...

Bargaining and trust: the effects of 36-h total sleep deprivation on socially interactive decisions.

Journal of Sleep Research — Tue, 13 Oct 2009 23:00:00 +0100

Authors: Anderson C, Dickinson DL Summary Although it is well known that sleep loss results in poor judgement and decisions, little is known about the influence of social context in these processes. Sixteen healthy young adults underwent three games involving bargaining ('Ultimatum' and 'Dictator') and trust, following total sleep deprivation (TSD) and during rested wakefulness (RW), in a repeated-measures, counterbalanced design. To control for repeatability, a second group (n = 16) was tested twice under RW conditions. Paired anonymously with another individual, participants made their simple social interaction decisions facing real monetary incentives. For bargaining, following TSD participants were more likely to reject unequal-split offers made by their partner, despite the reject...

Sleep disturbances as a predictor of occupational injuries among public sector workers

Journal of Sleep Research — Tue, 13 Oct 2009 23:00:00 +0100

This study suggests that sleep disturbances are a significant predictor of occupational injuries even after accounting for a range of covariates. (Source: Journal of Sleep Research)

Daytime sleepiness, psychomotor performance, waking EEG spectra and evoked potentials in women with severe premenstrual syndrome

Journal of Sleep Research — Tue, 13 Oct 2009 23:00:00 +0100

We assessed daytime sleepiness using objective and subjective measures in women with severe premenstrual syndrome (PMS) compared with women without significant premenstrual symptoms. Nine women with severe PMS and eight controls (aged 18[minus]40 years) completed a laboratory-based daytime protocol including the maintenance of wakefulness test (MWT), psychomotor vigilance task (PVT), quantitative waking electroencephalogram (EEG), auditory and visual event-related potentials (ERPs), and sleepiness and mood scales during the mid-follicular and late-luteal (premenstrual) phases of the menstrual cycle. In association with increased perceived sleepiness, fatigue and other premenstrual symptoms in the late-luteal phase, women with PMS performed more poorly on the PVT, with increased lapses and ...

Bargaining and trust: the effects of 36-h total sleep deprivation on socially interactive decisions

Journal of Sleep Research — Tue, 13 Oct 2009 23:00:00 +0100

Although it is well known that sleep loss results in poor judgement and decisions, little is known about the influence of social context in these processes. Sixteen healthy young adults underwent three games involving bargaining ('Ultimatum' and 'Dictator') and trust, following total sleep deprivation (TSD) and during rested wakefulness (RW), in a repeated-measures, counterbalanced design. To control for repeatability, a second group (n = 16) was tested twice under RW conditions. Paired anonymously with another individual, participants made their simple social interaction decisions facing real monetary incentives. For bargaining, following TSD participants were more likely to reject unequal-split offers made by their partner, despite the rejection resulting in a zero monetary payoff for bo...

Sleep and physical growth in infants during the first 6 months

Journal of Sleep Research — Tue, 13 Oct 2009 23:00:00 +0100

The aim of this study was to explore the relationships between infant sleep patterns and infant physical growth (weight for length ratio) using both objective and subjective sleep measures. Ninety-six first-born, healthy 6-month-old infants and their parents participated in the study. Infant sleep was assessed by actigraphy for four consecutive nights and by the Brief Infant Sleep Questionnaire (BISQ). In addition, parents were asked to complete background and developmental questionnaires. Questions about feeding methods were included in the developmental questionnaire. Infants' weight and length were assessed during a standard checkup at the infant-care clinic when the infants were 6 months old. Significant correlations were found between infant sleep and growth after controlling for pote...

Treatment effects on brain activity during a working memory task in obstructive sleep apnea.

Journal of Sleep Research — Wed, 16 Sep 2009 23:00:00 +0100

Authors: Aloia MS, Sweet LH, Jerskey BA, Zimmerman M, Todd Arnedt J, Millman RP Summary Positive airway pressure (PAP) is the most common form of treatment for obstructive sleep apnea (OSA). Treatment adherence is notoriously low, and holidays from treatment are common. To date, there is no literature on the effects of acute withdrawal from PAP treatment on the brain activity of individuals with OSA. Nine participants with OSA performed a 2-Back verbal working memory paradigm during repeated functional magnetic resonance imaging (FMRI). Counterbalanced FMRI sessions were under conditions of PAP treatment (at least one consecutive week) or non-treatment (for two consecutive nights). Treatment effects on 2-Back-related brain activity were significant, with greater deactivation in the rig...

Hypoxia-induced changes in recovery sleep, core body temperature, urinary 6-sulphatoxymelatonin and free cortisol after a simulated long-duration flight.

Journal of Sleep Research — Wed, 16 Sep 2009 23:00:00 +0100

This study shows clearly the impact of hypobaric hypoxia on circadian time structure during air flights leading to a phase delay of CBT, independent of jet lag and consequences on sleep during recovery. PMID: 19765206 [PubMed - as supplied by publisher] (Source: Journal of Sleep Research)

Treatment effects on brain activity during a working memory task in obstructive sleep apnea

Journal of Sleep Research — Wed, 16 Sep 2009 23:00:00 +0100

Positive airway pressure (PAP) is the most common form of treatment for obstructive sleep apnea (OSA). Treatment adherence is notoriously low, and holidays from treatment are common. To date, there is no literature on the effects of acute withdrawal from PAP treatment on the brain activity of individuals with OSA. Nine participants with OSA performed a 2-Back verbal working memory paradigm during repeated functional magnetic resonance imaging (FMRI). Counterbalanced FMRI sessions were under conditions of PAP treatment (at least one consecutive week) or non-treatment (for two consecutive nights). Treatment effects on 2-Back-related brain activity were significant, with greater deactivation in the right posterior insula and overactivation in the right inferior parietal lobule. The observed r...

Hypoxia-induced changes in recovery sleep, core body temperature, urinary 6-sulphatoxymelatonin and free cortisol after a simulated long-duration flight

Journal of Sleep Research — Wed, 16 Sep 2009 23:00:00 +0100

Sleep electroencephalogram in children with a parental history of alcohol abuse/dependence.

Journal of Sleep Research — Sun, 06 Sep 2009 23:00:00 +0100

We examined the sleep electroencephalogram (EEG) in 9- and 10-year-old children with (PH+) and without (PH-) a parental history of alcohol abuse/dependence to determine whether sleep disturbances associated with alcohol precede the onset of alcohol use. Participants slept on a fixed sleep schedule that ensured at least a 10-h time in bed for 1 week before an adaptation and baseline night. Data were collected in a four-bed sleep research laboratory. Thirty healthy boys and girls aged 9 or 10 years were classified as either PH+ or PH- based on DSM-IV criteria applied to structured parental interviews. All-night polysomnography was performed, sleep data were scored visually in 30-s epochs, and EEG power spectra were calculated for each epoch. All-night EEG spectra were calculated for rapid ey...

Sleep electroencephalogram in children with a parental history of alcohol abuse/dependence

Journal of Sleep Research — Sun, 06 Sep 2009 23:00:00 +0100

We examined the sleep electroencephalogram (EEG) in 9- and 10-year-old children with (PH+) and without (PH[minus]) a parental history of alcohol abuse/dependence to determine whether sleep disturbances associated with alcohol precede the onset of alcohol use. Participants slept on a fixed sleep schedule that ensured at least a 10-h time in bed for 1 week before an adaptation and baseline night. Data were collected in a four-bed sleep research laboratory. Thirty healthy boys and girls aged 9 or 10 years were classified as either PH+ or PH[minus] based on DSM-IV criteria applied to structured parental interviews. All-night polysomnography was performed, sleep data were scored visually in 30-s epochs, and EEG power spectra were calculated for each epoch. All-night EEG spectra were calculated ...

Medical exposures in youth and the frequency of narcolepsy with cataplexy: a population-based case–control study in genetically predisposed people

Journal of Sleep Research — Sun, 30 Aug 2009 23:00:00 +0100

Epidemiological observations suggest that exposures in youth may trigger narcolepsy in genetically predisposed individuals. In this population-based case[ndash]control study, we sought to identify all prevalent cases of narcolepsy with cataplexy aged 18[ndash]50 years as of 1 July 2001, in King County, Washington. The 45 eligible cases who were DQB1*0602-positive were compared with 95 controls with this allele, identified through random-digit dialing and buccal smears. Cases and controls were interviewed in person about physician-diagnosed infectious and non-infectious illnesses, immunizations, head trauma and parasomnias or psychiatric problems during youth. Narcolepsy with cataplexy was more frequent in African-Americans and in poorer households. Adjusting for these factors, the conditio...

Self-reported sleep duration and cognitive functioning in the general population

Journal of Sleep Research — Sun, 30 Aug 2009 23:00:00 +0100

This study investigated the relationship between self-reported sleep factors (sleep duration, insomnia, use of sleeping medicine, probable sleep apnoea and feelings of fatigue and tiredness) with cognitive functioning in 5177 people aged 30 years or older from a cross-sectional representative sample of the adult population in Finland (The Finnish Health 2000 Survey). Previous studies have indicated a U-shaped association between increased health risks and sleep duration; we hypothesized a U-shaped association between sleep duration and cognitive functioning. Objective cognitive functioning was assessed with tasks derived from the Consortium to Establish a Registry for Alzheimer's Disease test battery (verbal fluency, encoding and retaining verbal material). Subjective cognitive functioning...

Central apnoeas have significant effects on blood pressure and heart rate in children

Journal of Sleep Research — Sun, 30 Aug 2009 23:00:00 +0100

This study demonstrates that movement-induced CAs are more common in children with OSA, and are associated with significantly greater changes in HR and BP compared with spontaneous CAs. These data suggest that movement-induced CAs should be considered when assessing the cardiovascular impact of SDB. (Source: Journal of Sleep Research)

Sleep problems in general practice: a national survey of assessment and treatment routines of general practitioners in Norway

Journal of Sleep Research — Sun, 30 Aug 2009 23:00:00 +0100

This study demonstrates that sleep problems are recognized by GPs, but despite evidence that non-pharmacological treatment is superior in the long-term management of insomnia, the current study shows that hypnotics are still considered by GPs to be the most successful treatment. (Source: Journal of Sleep Research)

Heart rate increment analysis is not effective for sleep-disordered breathing screening in patients with chronic heart failure

Journal of Sleep Research — Sun, 30 Aug 2009 23:00:00 +0100

Frequency domain analysis of heart rate variation has been suggested as an effective screening tool for sleep-disordered breathing (SDB) in the general population. The aim of this study was to assess this method in patients with chronic congestive heart failure (CHF). We included prospectively 84 patients with stable CHF, left ventricular ejection fraction (LVEF) (Source: Journal of Sleep Research)

The race for the impact factor.

Journal of Sleep Research — Thu, 27 Aug 2009 11:08:09 +0100

Authors: Lavie P PMID: 19702787 [PubMed - in process] (Source: Journal of Sleep Research)

The impact of sleep duration and subject intelligence on declarative and motor memory performance: how much is enough?

Journal of Sleep Research — Thu, 27 Aug 2009 11:08:07 +0100

Authors: Tucker MA, Fishbein W Recent findings clearly demonstrate that daytime naps impart substantial memory benefits compared with equivalent periods of wakefulness. Using a declarative paired associates task and a procedural motor sequence task, this study examined the effect of two lengthier durations of nocturnal sleep [either a half night (3.5 h) or a full night (7.5 h) of sleep] on over-sleep changes in memory performance. We also assessed whether subject intelligence is associated with heightened task acquisition and, more importantly, whether greater intelligence translates to greater over-sleep declarative and procedural memory enhancement. Across both tasks, we demonstrate that postsleep performance gains are nearly equivalent, regardless of whether subjects obtain a half n...

Differential effects of lorazepam on sleep and activity in C57BL/6J and BALB/cJ strain mice.

Journal of Sleep Research — Thu, 27 Aug 2009 11:08:05 +0100

We examined the effects of two doses of lorazepam (0.5 and 1.5 mg kg(-1)) or saline alone (0.2 mL) on sleep and activity in C57BL/6 (n = 8) and BALB/c (n = 7) mice. Compared to saline, both doses of lorazepam significantly increased non-rapid eye movement (NREM) and reduced activity in both strains. In C57BL/6 mice, rapid eye movement (REM) was increased at both doses. In BALB/c mice, the 0.5 mg kg(-1) dose had no significant influence on REM, whereas REM was reduced significantly after the 1.5 mg kg(-1) dose. The results demonstrate significant differences between C57BL/6 and BALB/c mice in the effects of lorazepam on REM, whereas the effects on NREM and activity were similar. Strain differences in the number of BZ receptors in the amygdala, but not other brain regions, suggests possible ...

Daily light exposure profiles in older non-resident extreme morning and evening types

Journal of Sleep Research — Thu, 20 Aug 2009 23:00:00 +0100

This study aimed to investigate how patterns of daily light exposure in older non-resident M-types and E-types compare. Sleep diaries were kept during actigraphic measurement of activity and light using the Actiwatch-L for 14 days in 12 M-types [eight females, mean ± standard deviation (SD) Horne[ndash]Östberg Morning[ndash]Eveningness Questionnaire (HÖ MEQ) score 75.2 ± 1.6] and 11 E-types (seven females, HÖ MEQ 41.5 ± 4.8), over 60 years old, living in their own homes. Light data were log-transformed, averaged over each hour, and group × time analysis of covariance (ancova) performed with age as a covariate. M-types had significantly earlier bed and wake time than E-types, but there was no significant difference in sleep duration, sleep efficiency or time spent in bed between grou...

Usual sleep duration and cognitive function in older adults in Spain.

Journal of Sleep Research — Tue, 18 Aug 2009 23:00:00 +0100

Authors: Faubel R, López-García E, Guallar-Castillón P, Graciani A, Banegas JR, Rodríguez-Artalejo F Summary The few studies that have examined the association between usual sleep duration and cognitive function have shown conflicting results. This cross-sectional study examined the association between sleep duration and cognitive function among 3212 people, representative of the non-institutionalized population aged 60 years and over in Spain. Sleep duration was self-reported, and cognitive function was measured with the Mini-Examen Cognoscitivo (MEC), a version of the Mini-Mental State Examination that has been validated in Spain. Linear regression, with adjustment for the main confounders, was used to obtain mean differences in the MEC between the categories of s...

Stimulus type does not affect infant arousal response patterns.

Journal of Sleep Research — Tue, 18 Aug 2009 23:00:00 +0100

This study supports the nasal air-jet as an appropriate stimulus for assessing developmental patterns of infant arousal process. PMID: 19691474 [PubMed - as supplied by publisher] (Source: Journal of Sleep Research)

Daily light exposure profiles in older non-resident extreme morning and evening types.

Journal of Sleep Research — Tue, 18 Aug 2009 23:00:00 +0100

This study aimed to investigate how patterns of daily light exposure in older non-resident M-types and E-types compare. Sleep diaries were kept during actigraphic measurement of activity and light using the Actiwatch-L for 14 days in 12 M-types [eight females, mean +/- standard deviation (SD) Horne-Ostberg Morning-Eveningness Questionnaire (HO MEQ) score 75.2 +/- 1.6] and 11 E-types (seven females, HO MEQ 41.5 +/- 4.8), over 60 years old, living in their own homes. Light data were log-transformed, averaged over each hour, and group x time analysis of covariance (ancova) performed with age as a covariate. M-types had significantly earlier bed and wake time than E-types, but there was no significant difference in sleep duration, sleep efficiency or time spent in bed between groups. Daily exp...

Stimulus type does not affect infant arousal response patterns

Journal of Sleep Research — Tue, 18 Aug 2009 23:00:00 +0100

This study supports the nasal air-jet as an appropriate stimulus for assessing developmental patterns of infant arousal process. (Source: Journal of Sleep Research)

Usual sleep duration and cognitive function in older adults in Spain

Journal of Sleep Research — Tue, 18 Aug 2009 23:00:00 +0100

The few studies that have examined the association between usual sleep duration and cognitive function have shown conflicting results. This cross-sectional study examined the association between sleep duration and cognitive function among 3212 people, representative of the non-institutionalized population aged 60 years and over in Spain. Sleep duration was self-reported, and cognitive function was measured with the Mini-Examen Cognoscitivo (MEC), a version of the Mini-Mental State Examination that has been validated in Spain. Linear regression, with adjustment for the main confounders, was used to obtain mean differences in the MEC between the categories of sleep duration ([le]5, 6, 7, 8, 9, 10, [ge]11 h day[minus]1). The MEC score decreased progressively (became worse) across sleep catego...

Dysfunctional beliefs and attitudes about sleep in children

Journal of Sleep Research — Sun, 16 Aug 2009 23:00:00 +0100

The objective of the study was to determine whether associations between dysfunctional beliefs and attitudes about sleep and sleep disturbance are evident in children. Cross-sectional data were collected from 123 children aged 8[ndash]10 years (49% boys). The participants came from ethnically diverse backgrounds from two inner-city schools in London, UK. Children completed the Sleep Self-Report (SSR) and the Dysfunctional Beliefs and Attitudes about Sleep (DBAS) questionnaire (which was adapted for use with children). Parents completed the Child Sleep Habits Questionnaire (CSHQ). The total DBAS score was associated with sleep disturbances defined as total SSR score ([beta] = 0.40, P < 0.001, r2 = 0.15), the SSR insomnia items ([beta] = 0.29, P < 0.01, r2 = 0.08) and the total CSHQ score ([...

Dysfunctional beliefs and attitudes about sleep in children.

Journal of Sleep Research — Sat, 15 Aug 2009 23:00:00 +0100

The objective of the study was to determine whether associations between dysfunctional beliefs and attitudes about sleep and sleep disturbance are evident in children. Cross-sectional data were collected from 123 children aged 8-10 years (49% boys). The participants came from ethnically diverse backgrounds from two inner-city schools in London, UK. Children completed the Sleep Self-Report (SSR) and the Dysfunctional Beliefs and Attitudes about Sleep (DBAS) questionnaire (which was adapted for use with children). Parents completed the Child Sleep Habits Questionnaire (CSHQ). The total DBAS score was associated with sleep disturbances defined as total SSR score (beta = 0.40, P < 0.001, r(2) = 0.15), the SSR insomnia items (beta = 0.29, P < 0.01, r(2) = 0.08) and the total CSHQ score (b...

Retrograde effects of triazolam and zolpidem on sleep-dependent motor learning in humans

Journal of Sleep Research — Thu, 13 Aug 2009 23:00:00 +0100

Drugs that act as allosteric activators at the benzodiazepine site of the gamma-aminobutyric acid (GABAA) receptor complex are used commonly to treat insomnia but relatively little is known of how such use affects learning and memory. Although anterograde effects on memory acquisition have been shown, possible retrograde effects on consolidation are more relevant when such agents are administered at bedtime. We tested the effects of two GABAA allosteric activators on sleep-dependent motor skill memory consolidation in 12 healthy male subjects. Subjects slept in a sleep laboratory for four consecutive nights (one accommodation night followed by three experimental nights). Placebo, triazolam 0.375 mg, and zolpidem 10 mg were given to each subject in counterbalanced order on the experimental ...

Retrograde effects of triazolam and zolpidem on sleep-dependent motor learning in humans.

Journal of Sleep Research — Wed, 12 Aug 2009 23:00:00 +0100

Authors: Morgan PT, Kehne JH, Sprenger KJ, Malison RT Drugs that act as allosteric activators at the benzodiazepine site of the gamma-aminobutyric acid (GABA(A)) receptor complex are used commonly to treat insomnia but relatively little is known of how such use affects learning and memory. Although anterograde effects on memory acquisition have been shown, possible retrograde effects on consolidation are more relevant when such agents are administered at bedtime. We tested the effects of two GABA(A) allosteric activators on sleep-dependent motor skill memory consolidation in 12 healthy male subjects. Subjects slept in a sleep laboratory for four consecutive nights (one accommodation night followed by three experimental nights). Placebo, triazolam 0.375 mg, and zolpidem 10 mg were given...

Sleep state distribution of obstructive events in children: is obstructive sleep apnoea really a rapid eye movement sleep-related condition?

Journal of Sleep Research — Wed, 12 Aug 2009 23:00:00 +0100

Authors: Verginis N, Jolley D, Horne RS, Davey MJ, Nixon GM Obstructive sleep apnoea (OSA) in children is commonly considered to occur predominantly in rapid eye movement (REM) sleep, but clinical experience suggests that this is not universally the case. We hypothesized that there would be a subgroup of children with OSA who have non-REM (NREM) predominance of obstructive events and that these children share certain clinical characteristics. Thus, we aimed to compare the obstructive apnoea-hypopnoea index (OAHI) in REM versus NREM sleep and to assess factors influencing the distribution of events by sleep state. Polysomnography (PSG) recordings of 102 children aged 0-18 years with moderate to severe OSA (OAHI >/=5 h(-1)) were reviewed. OAHI was calculated separately for REM and NRE...

Factor structure of the Athens Insomnia Scale and its associations with demographic characteristics and depression in adolescents.

Journal of Sleep Research — Wed, 12 Aug 2009 23:00:00 +0100

This study aimed to examine the prevalence rates of insomnia problems on the AIS-8, the factor structure of the AIS-8 in adolescents and its associations with demographic characteristics and depression in adolescents. A total of 8319 adolescent students (4334 girls and 3985 boys, mean age = 14.7 years, standard deviation = 1.7 years) in southern Taiwan were recruited into this study and completed the AIS-8. We performed an exploratory factor analysis to examine the factor structure of the AIS-8, and used the parallel analysis for making decisions regarding factor retention. We also used multiple regression analysis models to determine the associations between insomnia and demographic characteristics and depression. The results found that a high proportion of adolescents had insomnia proble...

Factor structure of the Athens Insomnia Scale and its associations with demographic characteristics and depression in adolescents

Journal of Sleep Research — Wed, 12 Aug 2009 23:00:00 +0100

Sleep state distribution of obstructive events in children: is obstructive sleep apnoea really a rapid eye movement sleep-related condition?

Journal of Sleep Research — Wed, 12 Aug 2009 23:00:00 +0100

Obstructive sleep apnoea (OSA) in children is commonly considered to occur predominantly in rapid eye movement (REM) sleep, but clinical experience suggests that this is not universally the case. We hypothesized that there would be a subgroup of children with OSA who have non-REM (NREM) predominance of obstructive events and that these children share certain clinical characteristics. Thus, we aimed to compare the obstructive apnoea[ndash]hypopnoea index (OAHI) in REM versus NREM sleep and to assess factors influencing the distribution of events by sleep state. Polysomnography (PSG) recordings of 102 children aged 0[ndash]18 years with moderate to severe OSA (OAHI [ge]5 h[minus]1) were reviewed. OAHI was calculated separately for REM and NREM sleep. A REM predominance index (RPI) was determ...

Nitric oxide modulates the discharge rate of basal forebrain neurones: a study in freely moving rats.

Journal of Sleep Research — Tue, 04 Aug 2009 23:00:00 +0100

The objective of this study was to examine whether NO modulates the discharge rate of BF neurones in freely moving rats in a similar manner to anaesthetized rats. We measured the discharge rates of BF neurones in freely moving rats during microdialysis infusion of a NO-donor (1 mm; NOC-18) in different vigilance states. Neurones were characterized as wake (W)-on (51.8%), W-off (28.6%) and W/non-rapid eye movement (REM)-independent (21.4%) based on their discharge profiles during wakefulness (W) and non-REM sleep. The NO-donor affected the discharge rate of most BF neurones during quiet wakefulness (QW; 55%) and non-REM sleep (64%). The most prominent response in all neuronal groups was a decrease in the discharge rate during QW and non-REM sleep. A small subpopulation of neurones increased...

Nitric oxide modulates the discharge rate of basal forebrain neurones: a study in freely moving rats

Journal of Sleep Research — Tue, 04 Aug 2009 23:00:00 +0100

Sleep architecture changes during a trek from 1400 to 5000 m in the Nepal Himalaya

Journal of Sleep Research — Mon, 03 Aug 2009 23:00:00 +0100

The aim of this study was to examine sleep architecture at high altitude and its relationship to periodic breathing during incremental increases in altitude. Nineteen normal, sea level-dwelling volunteers were studied at sea level and five altitudes in the Nepal Himalaya. Morning arterial blood gases and overnight polysomnography were performed in 14 subjects at altitudes: 0, 1400, 3500, 3900, 4200 and 5000 m above sea level. Subjects became progressively more hypoxic, hypocapnic and alkalinic with increasing altitude. As expected, sleep architecture was affected by increasing altitude. While time spent in Stage 1 non-rapid eye movement sleep increased at 3500 m and higher (P < 0.001), time spent in slow-wave sleep (SWS) decreased as altitude increased. Time spent in rapid eye movement (RE...

Sleep architecture changes during a trek from 1400 to 5000 m in the Nepal Himalaya.

Journal of Sleep Research — Sun, 02 Aug 2009 23:00:00 +0100

Authors: Johnson PL, Edwards N, Burgess KR, Sullivan CE The aim of this study was to examine sleep architecture at high altitude and its relationship to periodic breathing during incremental increases in altitude. Nineteen normal, sea level-dwelling volunteers were studied at sea level and five altitudes in the Nepal Himalaya. Morning arterial blood gases and overnight polysomnography were performed in 14 subjects at altitudes: 0, 1400, 3500, 3900, 4200 and 5000 m above sea level. Subjects became progressively more hypoxic, hypocapnic and alkalinic with increasing altitude. As expected, sleep architecture was affected by increasing altitude. While time spent in Stage 1 non-rapid eye movement sleep increased at 3500 m and higher (P < 0.001), time spent in slow-wave sleep (SWS) decrea...

Unexpected survival advantage in elderly people with moderate sleep apnoea.

Journal of Sleep Research — Sun, 02 Aug 2009 23:00:00 +0100

This study investigated retrospectively the rates of all-cause mortality in elderly people (>/= 65 years) with a laboratory diagnosis of sleep apnoea, and compared their rates of mortality with that of age-, gender- and ethnicity-matched national mortality data. Survival of 611 elderly people was ascertained after a follow-up of 5.17 +/- 1.13 years. Their age was 70.4 +/- 4.8 years, body mass index 30.4 +/- 5.9 kg m(-2) and respiratory disturbance index (RDI) 28.9 +/- 20.1 events h(-1). Seventy-five (12.27%) patients died during the follow-up period. In comparison with the demographically matched cohort from the general population, the standardized mortality rate of the sleep laboratory cohort was 0.67 [95% confidence interval (CI): 0.53-0.88; chi(2) = 11.69, P < 0.0006]. When calcul...

Unexpected survival advantage in elderly people with moderate sleep apnoea

Journal of Sleep Research — Sun, 02 Aug 2009 23:00:00 +0100

This study investigated retrospectively the rates of all-cause mortality in elderly people ([ge] 65 years) with a laboratory diagnosis of sleep apnoea, and compared their rates of mortality with that of age-, gender- and ethnicity-matched national mortality data. Survival of 611 elderly people was ascertained after a follow-up of 5.17 ± 1.13 years. Their age was 70.4 ± 4.8 years, body mass index 30.4 ± 5.9 kg m[minus]2 and respiratory disturbance index (RDI) 28.9 ± 20.1 events h[minus]1. Seventy-five (12.27%) patients died during the follow-up period. In comparison with the demographically matched cohort from the general population, the standardized mortality rate of the sleep laboratory cohort was 0.67 [95% confidence interval (CI): 0.53[ndash]0.88; [chi]2 = 11.69, P < 0.0006]. When c...

Linking impulsivity to dysfunctional thought control and insomnia: a structural equation model.

Journal of Sleep Research — Tue, 28 Jul 2009 23:00:00 +0100

This study examined the relations between impulsivity, use of different thought-control strategies and insomnia severity. A sample of 391 university students completed the UPPS Impulsive Behavior Scale, the Thought Control Questionnaire Insomnia-Revised and the Insomnia Severity Index. Correlation analyses revealed that two facets of impulsivity (urgency and lack of perseverance), two strategies of thought control (aggressive suppression and worry) and insomnia severity were positively associated. Follow-up structural equation modeling analyses showed that the two mentioned thought-control strategies mediated the effects of the two facets of impulsivity on sleep problems. These findings extend existing cognitive accounts of insomnia by suggesting how predisposing and perpetuating factors m...

Linking impulsivity to dysfunctional thought control and insomnia: a structural equation model

Journal of Sleep Research — Tue, 28 Jul 2009 23:00:00 +0100

No persisting effect of partial sleep curtailment on cognitive performance and declarative memory recall in adolescents.

Journal of Sleep Research — Mon, 27 Jul 2009 23:00:00 +0100

Authors: Kopasz M, Loessl B, Valerius G, Koenig E, Matthaeas N, Hornyak M, Kloepfer C, Nissen C, Riemann D, Voderholzer U Growing evidence indicates that sleep facilitates learning and memory processing. Sleep curtailment is increasingly common in adolescents. The aim of this study was to examine the effects of short-term sleep curtailment on declarative memory consolidation in adolescents. A randomized, cross-over study design was chosen. Twenty-two healthy subjects, aged 14-16 years, spent three consecutive nights in the sleep laboratory with a bedtime of 9 h during the first night (adaptation), 4 h during the second (partial sleep curtailment) and 9 h during the third night (recovery). The control condition consisted of three consecutive nights with bedtimes of 9 h. Both experimenta...

No persisting effect of partial sleep curtailment on cognitive performance and declarative memory recall in adolescents

Journal of Sleep Research — Mon, 27 Jul 2009 23:00:00 +0100

Growing evidence indicates that sleep facilitates learning and memory processing. Sleep curtailment is increasingly common in adolescents. The aim of this study was to examine the effects of short-term sleep curtailment on declarative memory consolidation in adolescents. A randomized, cross-over study design was chosen. Twenty-two healthy subjects, aged 14[ndash]16 years, spent three consecutive nights in the sleep laboratory with a bedtime of 9 h during the first night (adaptation), 4 h during the second (partial sleep curtailment) and 9 h during the third night (recovery). The control condition consisted of three consecutive nights with bedtimes of 9 h. Both experimental conditions were separated by at least 3 weeks. The acquisition phase for the declarative tests was between 16:00 and 1...

Sleep-related sweating in obstructive sleep apnoea: association with sleep stages and blood pressure

Journal of Sleep Research — Wed, 22 Jul 2009 23:00:00 +0100

The aim of this study was to investigate sleep-related sweating as a symptom of obstructive sleep apnoea (OSA). Fifteen otherwise healthy male non-smoking patients with untreated moderate-to-severe OSA underwent polysomnography, including measurements of skin and core body temperature and electrodermal activity (EDA) as an objective indicator of sweating. Evening and morning blood pressure was measured as well as catecholamines in nocturnal urine. All measurements were repeated after 3 months on successful continuous positive airway pressure (CPAP) treatment. The untreated OSA subjects had a mean (±SD) apnoea[ndash]hypopnoea index of 45.3 ± 3.9 and a mean EDA index during sleep of 131.9 ± 22.4 events per hour. Patients with higher EDA indices had higher systolic blood pressure in the ev...

Sleep-related sweating in obstructive sleep apnoea: association with sleep stages and blood pressure.

Journal of Sleep Research — Tue, 21 Jul 2009 23:00:00 +0100

Authors: Arnardottir ES, Thorleifsdottir B, Svanborg E, Olafsson I, Gislason T The aim of this study was to investigate sleep-related sweating as a symptom of obstructive sleep apnoea (OSA). Fifteen otherwise healthy male non-smoking patients with untreated moderate-to-severe OSA underwent polysomnography, including measurements of skin and core body temperature and electrodermal activity (EDA) as an objective indicator of sweating. Evening and morning blood pressure was measured as well as catecholamines in nocturnal urine. All measurements were repeated after 3 months on successful continuous positive airway pressure (CPAP) treatment. The untreated OSA subjects had a mean (+/-SD) apnoea-hypopnoea index of 45.3 +/- 3.9 and a mean EDA index during sleep of 131.9 +/- 22.4 events per hou...

Prevalence, comorbidities and risk factors of restless legs syndrome in the Korean elderly population – results from the Korean Longitudinal Study on Health and Aging

Journal of Sleep Research — Tue, 21 Jul 2009 23:00:00 +0100

The aim of this study was to determine the prevalence, neuropsychiatric comorbidities, iron metabolism and potential risk factors of restless legs syndrome (RLS) in the elderly Korean population. As a community-based epidemiological study, a simple random sample of 1118 was drawn from a roster of 61 730 adult individuals aged 65 years and older and 714 participated. The diagnosis of RLS was established in face-to-face interviews using the four minimal diagnostic criteria for RLS recommended by National Institute of Health. Depressive symptoms, nocturnal sleep disturbances, daytime sleepiness and quality of life were evaluated. Laboratory tests of iron metabolism, markers of inflammation, renal and endocrine function, hormones and vitamins were performed. A total of 59 patients (42 women an...

Increase in serum haptoglobin and apolipoprotein M in patients with obstructive sleep apnoea.

Journal of Sleep Research — Mon, 29 Jun 2009 23:00:00 +0100

This study was undertaken to identify serum proteins associated with OSA by using a proteomics technique and to examine changes in identified protein levels after continuous positive airway pressure treatment. The study participants consisted of 40 male patients (aged 40-49 years) with severe OSA and 34 male control subjects matched for age and body mass index. All subjects underwent polysomnography. Using a proteomics approach, we identified nine proteins that were differentially expressed in patients with severe OSA and controls. Three of these nine proteins, haptoglobin, paraoxonase-1 and apolipoprotein M, were quantified by using enzyme-linked immunosorbent assays, kinetic assays and by using Western blotting. Multiple regression analysis showed that haptoglobin and apolipoprotein M le...

Increase in serum haptoglobin and apolipoprotein M in patients with obstructive sleep apnoea

Journal of Sleep Research — Mon, 29 Jun 2009 23:00:00 +0100

This study was undertaken to identify serum proteins associated with OSA by using a proteomics technique and to examine changes in identified protein levels after continuous positive airway pressure treatment. The study participants consisted of 40 male patients (aged 40[ndash]49 years) with severe OSA and 34 male control subjects matched for age and body mass index. All subjects underwent polysomnography. Using a proteomics approach, we identified nine proteins that were differentially expressed in patients with severe OSA and controls. Three of these nine proteins, haptoglobin, paraoxonase-1 and apolipoprotein M, were quantified by using enzyme-linked immunosorbent assays, kinetic assays and by using Western blotting. Multiple regression analysis showed that haptoglobin and apolipoprotei...

Information processing during sleep: the effect of olfactory stimuli on dream content and dream emotions

Journal of Sleep Research — Wed, 24 Jun 2009 23:00:00 +0100

Research has shown that external stimuli presented during sleep can affect dream content, thus reflecting information processing of the sleeping brain. Olfactory stimuli should have a stronger effect on dream emotions because their processing is linked directly to the limbic system. Because selective olfactory stimulation does not increase arousal activity, intense olfactory stimulation is therefore a prime paradigm for studying information processing during sleep. Fifteen healthy, normosmic volunteers were studied by intranasal chemosensory stimulation during rapid eye movement sleep based on air-dilution olfactometry. For olfactory stimulation, hydrogen sulphide (smell of rotten eggs) and phenyl ethyl alcohol (smell of roses) was used and compared with a control condition without stimula...

Continuous positive airway pressure treatment for obstructive sleep apnoea reduces resting heart rate but does not affect dysrhythmias: a randomised controlled trial.