Loss of REM sleep features across nighttime in REM sleep behavior disorder

ObjectivesMelatonin is a chronobiotic treatment which also alleviates rapid eye movement (REM) sleep behavior disorder (RBD). Because the mechanisms of this benefit are unclear, we evaluated the clock-dependent REM sleep characteristics in patients with RBD, whether idiopathic (iRBD) or associated with Parkinson's Disease (PD), and we compared findings with PD patients without RBD and with healthy subjects.MethodsAn overnight videopolysomnography was performed in ten iRBD patients, ten PD patients with RBD (PD + RBD+), ten PD patients without RBD (PD + RBD−), and ten controls. The rapid eye movement frequency per minute (REMs index), the tonic and phasic electromyographic (EMG) activity of the levator menti muscle, and the duration of each REM sleep episode were evaluated. A generalized linear model was applied in each group, with the REM sleep cycle (four ordinal levels) as the dependent variable, as a function of REMs index, REM sleep duration, and tonic and phasic EMG activity.ResultsFrom the first to the fourth sleep cycle, REM sleep duration progressively increased in controls only, REMs index increased in subjects without RBD but not in patients with RBD, whether idiopathic or associated with PD, whereas tonic and phasic EMG activity did not change.ConclusionsPatients with PD or iRBD lost the physiologic nocturnal increase in REM sleep duration, and patients with RBD (either with or without PD) lost the increase of REMs frequency across the night, suggesting an alteration in the circadian system in RBD. This supports the hypothesis of a direct effect of melatonin on RBD symptoms by its chronobiotic activity.     

A preliminary quantitative analysis of REM sleep chin EMG in Parkinson's disease with or without REM sleep behavior disorder

ObjectivesTo compare REM sleep chin EMG quantitative features between Parkinson’s disease (PD) patients with or without REM sleep behavior disorder (RBD).Subjects and methodsTwenty-seven consecutive PD patients (mean age 67.9 years) and 19 normal controls (mean age 67.5 years) were enrolled. Detailed clinical, laboratory, and polysomnographic studies were obtained in all participants and characteristics of chin electromyographic amplitude during rapid eye movements sleep were analyzed by means of an automatic quantitative approach (Atonia Index).ResultsSixteen of the 27 patients were affected by RBD. An Atonia Index below 0.90 showed high sensitivity (0.938) and specificity (0.909) for the diagnosis of RBD within the group of PD patients.ConclusionThis study recommends the Atonia Index as an objective measure to support and aid the diagnosis of RBD in PD.     

Comparison of severity of obstructive sleep apnea and degree of accumulation of cardiac 123I-MIBG radioactivity as a diagnostic marker for idiopathic REM sleep behavior disorder

ObjectiveWe investigated cardiac ¹²³I-metaiodobenzylguanidine (MIBG) scintigraphic assessment as a supportive diagnostic indicator for idiopathic REM sleep behavior disorder (RBD) complicated by moderate to severe obstructive sleep apnea (OSA).Methods¹²³I-MIBG was intravenously injected in 23 idiopathic RBD patients with AHI < 5/h, 9 idiopathic RBD patients with 5 ? AHI < 15/h, 15 idiopathic RBD patients complicated with moderate to severe OSA with AHI ? 15/h, and 16 moderate to severe obstructive sleep apnea syndrome (OSAS) patients without RBD by polysomnography.ResultsCardiac MIBG uptake based on H/M was significantly decreased in RBD patients with or without OSA compared with patients with moderate to severe OSAS without RBD. ROC analysis revealed that a delayed H/M cut-off value of 1.97 was useful for differentiating idiopathic RBD complicated by moderate to severe OSA from moderate to severe OSAS without RBD.Conclusions¹²³I-MIBG cardiac scintigraphy has the potential to distinguish true RBD from pseudo-RBD associated with OSA. These results are noteworthy because treatment options and follow-up protocols are determined based on evaluation of moderate to severe OSA complicated with RBD, such as overlapping primary sleep disorders.     

REM and NREM sleep enactment behaviors in Parkinson's disease, Parkinson's disease dementia, and dementia with Lewy bodies

Background/objectiveNocturnal sleep enactment behaviors (SEBs) are common in patients affected by Parkinson’s disease (PD), dementia associated with Parkinson’s disease (PDD), and dementia with Lewy bodies (DLB). We investigated the occurrence and neurobiological significance of abnormal SEBs in the context of PD without cognitive decline compared to PDD/DLB patients.MethodsWe evaluated a sample of 139 patients with PD, PDD, or DLB in a cross-sectional survey. One hundred and seventeen patients showing either no cognitive impairment (PD group) or meeting the diagnostic requirements for dementia (PDD/DLB group) underwent video-polysomnography. Seventy subjects (42 males) in whom a clear-cut diagnosis of abnormal sleep-related motor-behavioral episodes was possible were included in the final analysis.ResultsSEBs consisting of RBD or occurring on arousal from NREM or REM sleep were globally more frequent in the dementia group (PDD/DLB) than in the PD group (p = 0.001), the difference being statistically significant for arousal-related episodes (p = 0.002), while a trend emerged for RBD (p = 0.07). Male sex, daytime sleepiness, higher motor impairment, and lower mini-mental score were significantly more frequent with the occurrence of abnormal sleep-related motor-behavioral episodes.ConclusionSEBs in PD, PDD, and DLB may consist of RBD episodes or of arousal-related NREM and REM episodes. These latter are more frequent in patients with PDD/DLB and seem to be mainly related to more advanced stages of disease with a higher degree of cognitive decline.     

REM sleep behavior disorder in 703 sleep-disorder patients: The importance of eliciting a comprehensive sleep history

ObjectivesThe aim of our study was to evaluate the frequency of REM sleep behavior disorder (RBD) in a mixed sleep laboratory population and to assess potential associations. Moreover, we investigated referral diagnoses of patients subsequently diagnosed with RBD and assessed the frequency of incidental RBD.MethodsCharts and polysomnographic reports of 703 consecutive patients comprising the full spectrum of ICSD-2 sleep disorders [501 males, 202 females; mean age, 51.0 ± 14.1 years (range: 10–82 years)] were carefully reviewed. The vast majority of patients were adults (98.7%). Patients were categorized into those with and without RBD. For associations, all concomitant sleep and neurological diagnoses and medications were evaluated.ResultsThirty-four patients (4.8%) were diagnosed with RBD (27 men; 7 women, mean age, 57.7 ± 12.3 years). RBD was idiopathic in 11 patients (1.6%; 9 men) and symptomatic in 23 patients (3.3%; 18 men) secondary to Parkinsonian syndromes (n = 11), use of antidepressants (n = 7), narcolepsy with cataplexy (n = 4), and pontine infarction (n = 1). Six out of 34 patients were referred for suspected RBD, 20 reported RBD symptoms only on specific questioning, and 8 patients had no history of RBD but showed typical RBD behavioral manifestations in the video-polysomnography. Logistic regression analysis revealed significant associations between RBD and the presence of Parkinsonian syndromes (odds ratio [OR] 16.8, 95%CI: 6.4–44.1; P < 0.001), narcolepsy with cataplexy (OR 10.7, 95%CI: 2.9–40.2; P < 0.001), SSRI use (OR 3.9, 95%CI: 1.6–9.8; P = 0.003), and age (OR 1.5/10-year increase, 95%CI: 1.0–2.0; P = 0.039).ConclusionIn this population of 703 consecutive sleep-disorder patients, RBD was uncommon. Its etiology was predominantly symptomatic. The majority of RBD patients reported RBD symptoms on specific questioning only, underlining the importance of eliciting a comprehensive sleep history for the diagnosis of RBD.     

Comparison of supine-only and REM-only obstructive sleep apnoea

ObjectivesThe effect of body position and sleep state on sleep apnoea have major clinical implications in the management of patients, yet are infrequently reported in the scientific literature. The aim of this study was to compare and contrast the prevalence and severity of supine-only and rapid eye movement (REM)-only obstructive sleep apnoea (OSA) in a population.MethodsProspective cohort analysis of the influence of supine body position and REM sleep on the severity of apnoea in 100 consecutive patients with OSA (apnoea–hypopnoea index [AHI] > 5) using attended polysomnography with continuous digital monitoring in an accredited sleep laboratory. Supine-only OSA was defined as a supine:non-supine AHI ratio of >2:1 and non-supine AHI <5 events/h. REM-only OSA was defined as an REM:non-REM ratio of >2:1 and non-REM AHI <5 events/h.ResultsSupine sleep time represented a greater proportion of total sleep time than REM sleep time (40% vs 13%). The prevalence of supine-only OSA was more than twofold greater than that of REM-only OSA (23% and 10%, respectively). The supine-only group had greater overall AHI (mean 12.6 ± 6.1 vs 7.2 ± 2.2 events/h; P < 0.01) than the REM-only group. No significant differences in gender, age, or sleepiness were found between the two groups.ConclusionsSupine-only OSA is more common and is associated with a greater AHI than REM-only OSA.     

REM rebound and CPAP compliance

Objective/BackgroundThe objective of this study was establish if rapid-eye-movement (REM) rebound on first exposure to continuous positive airway pressure (CPAP) is associated with CPAP compliance. A rebound or drastic increase in REM sleep in response to initial CPAP exposure is associated with improvement in the subjective quality of sleep. We wished to determine if REM rebound was also associated with increased CPAP compliance.MethodsSplit night polysomnographic studies carried out in a one-and-a-half year period were examined for REM rebound and slow wave sleep (SWS) rebound. Compliance with CPAP according to percentage of days used and percentage of days used for more than 4 h was determined at 30, 60, and 120 days and compared between groups with and without REM rebound and then between groups with and without SWS rebound. Multivariate regression models were constructed to determine factors that were associated with increasing CPAP compliance.ResultsCPAP compliance was greater for those with REM rebound than those without REM rebound at all time periods, but significantly so only for total percentage of days used at 30 days (86.7 ± 46.7, 96.7 vs. 56.7 [median ± 1st quartile, 3rd quartile] ± 32.5, 90.0; p = 0.04) and 60 days (78.3 ± 37.5, 93.4 vs. 50.0 ± 25.0, 80.9; p = 0.03). There was no difference in CPAP compliance for SWS rebound and there were no SWS rebound groups. Only the presence of REM rebound was associated with increased compliance with CPAP with neither SWS rebound nor diagnostic AHI being significantly associated with CPAP compliance.ConclusionsThe presence of REM rebound, but not SWS rebound, on initial CPAP exposure is associated with early CPAP compliance. This increased compliance is not explained by severity of sleep apnea as measured by AHI.     

REM sleep characteristics of nightmare sufferers before and after REM sleep deprivation

ObjectivesTo examine whether disrupted regulation of REM sleep propensity is implicated in nightmare (NM) pathophysiology.BackgroundHeightened REM propensity induced by REM sleep deprivation is belied by increases in REM %, REM density and the dreamlike quality of dream mentation during post-deprivation recovery sleep. Compromised regulation of REM sleep propensity may be a contributing factor in the pathophysiology of frequent NMs.MethodsA preliminary study of 14 subjects with frequent NMs (?1 NM/week; 27.6 ± 9.9 years) and 11 healthy control subjects (<1 NM/month; 24.3 ± 5.3 years) was undertaken. Subjects completed home sleep/dream logs and underwent three nights of polysomnographic recording with REM sleep deprivation on night 2. Group differences were assessed for a battery of REM sleep and dream measures on nights 1 and 3.ResultsSeveral measures, including #skipped early-night REM periods, REM latency, REM/NREM cycle length, early/late REM density,REM rebound, late-night REM% and dream vividness, suggested that REM sleep propensity was abnormally low for the frequent NM group throughout the 3-day study.ConclusionsFindings raise the possibility that REM anomalies recorded from NM sufferers sleeping in the laboratory environment reflect a disruption of one or more endogenous regulators of REM sleep propensity.     

REM sleep behavior disorder in Parkinson disease: Association with abnormal ocular motor findings

BackgroundThe anatomical substrates associated with generalized muscle atonia during REM sleep are located on the pontine tegmentum and medial medulla oblongata. We examined whether patients with REM sleep behavior disorder (RBD) have abnormal ocular movements suggesting brainstem or cerebellar dysfunction in Parkinson's disease (PD).MethodsCross-sectional survey for the existence of RBD and abnormal ocular movements. Ocular movements were examined by video-oculography (VOG).ResultsA total of 202 patients were included in this study. One hundred and sixteen (57.4%) of the 202 patients have clinically probable RBD, and 28 (24.1%) of the 116 with clinically probable RBD patients had abnormal VOG findings suggesting brainstem or cerebellar dysfunction; whereas 86 of the 202 patients did not have clinically probable RBD, and only 7 (8.1%) of the 86 patients had abnormal VOG findings suggesting brainstem or cerebellar dysfunction (P = 0.001).ConclusionThis study suggests that the presence of RBD is associated with more severe or extensive brainstem pathology or different distribution of pathology in PD.     

Validation of the Japanese version of the REM sleep behavior disorder questionnaire (RBDQ-JP)

BackgroundThe rapid eye movement (REM) sleep behavior disorder (RBD) questionnaire (RBDQ)-Hong Kong was the first tool developed for quantifying the severity of RBD. This study was conducted to validate the Japanese version of the questionnaire and to investigate its reliability, validity, and responsiveness.MethodsPatients with idiopathic RBD and sex and age-matched healthy controls completed the Japanese version of the questionnaire (RBDQ-JP). In addition to the evaluation of its reliability and validity, the questionnaire scores were compared between those earned before and those earned after pharmaceutical treatment to assess the questionnaire’s responsiveness.ResultsThe questionnaire demonstrated high test–retest reliability and moderate internal consistency. The best cut-off score was 19/20 with a sensitivity of 97.2% and a specificity of 97.5%. Exploratory factor analysis revealed that the questionnaire consists of the following two factors: Factor 1, Dream and dream-related behaviors and Factor 2, Violent/complex behaviors. Among the patients, significant correlation was found between the rate of change of questionnaire score and the clinical global impression improvement score with pharmaceutical treatment (rs = ?0.829, p < 0.01).ConclusionsThe RBDQ-JP provides satisfactory reliability, validity, and responsiveness. The questionnaire is suitable for severity assessment and for assessing the RBD treatment outcome.     

Polysomnographic findings, video-based sleep analysis and sleep perception in progressive supranuclear palsy

Objectives: To compare subjective sleep perception, sleep architecture, rapid eye movement (REM) sleep without atonia, and REM sleep behavior disorder (RBD) in patients with progressive supranuclear palsy (PSP) to patients with Parkinson’s disease (PD).Methods: A comparative sleep study using the Parkinson’s Disease Sleep Scale (PDSS), the Mini-Mental State Examination (MMSE), and cardiorespiratory polysomnography on two consecutive nights with synchronized video recording. The study was undertaken in a sleep laboratory in a movement disorder center. Forty patients matched for age and cognition with probable PSP (n = 20, aged 71 ± 8 years, MMSE ? 24 in n = 7) and PD (n = 20, aged 69 ± 5 years, MMSE ? 24 in n = 8).Results: PDSS sum scores showed no difference between PSP and PD. PSP patients had significantly lower sleep efficiency (43.0 ± 15.0%) compared to PD patients (62.8 ± 19.1%) (p < 0.0008). Seventeen PSP patients and 19 PD patients had REM without atonia (RWA). Seven PSP patients and 13 PD patients had clinical RBD. The amount of RWA was lower in PSP (14.5 ± 17.3%) than in PD (44.6 ± 31.3%) (p < 0.0007). Eleven PSP and 11 PD patients were newly identified with sleep-disordered breathing (SDB).Conclusions: Polysomnographically recorded sleep is more severely impaired in PSP than in PD. PDSS ratings do not reflect the poorer sleep quality in PSP, possibly pointing to a specific neuropsychological profile. RWA and RBD are present in both neurodegenerative diseases. So far undetected SDB affects more than half of all patients in this study.     

Treatment outcomes in REM sleep behavior disorder

ObjectiveREM sleep behavior disorder (RBD) is usually characterized by potentially injurious dream enactment behaviors (DEB). RBD treatment aims to reduce DEBs and prevent injury, but outcomes require further elucidation. We surveyed RBD patients to describe longitudinal treatment outcomes with melatonin and clonazepam.MethodsWe surveyed and reviewed records of consecutive RBD patients seen at Mayo Clinic between 2008–2010 to describe RBD-related injury frequency–severity as well as RBD visual analog scale (VAS) ratings, medication dosage, and side effects. Statistical analyses were performed with appropriate non-parametric matched pairs tests before and after treatment, and with comparative group analyses for continuous and categorical variables between treatment groups. The primary outcome variables were RBD VAS ratings and injury frequency.ResultsForty-five (84.9%) of 53 respondent surveys were analyzed. Mean age was 65.8 years and 35 (77.8%) patients were men. Neurodegenerative disorders were seen in 24 (53%) patients and 25 (56%) received antidepressants. Twenty-five patients received melatonin, 18 received clonazepam, and two received both as initial treatment. Before treatment, 27 patients (60%) reported an RBD associated injury. Median dosages were melatonin 6 mg and clonazepam 0.5 mg. RBD VAS ratings were significantly improved following both treatments (p_m = 0.0001, p_c = 0.0005). Melatonin-treated patients reported significantly reduced injuries (p_m = 0.001, p_c = 0.06) and fewer adverse effects (p = 0.07). Mean durations of treatment were no different between groups (for clonazepam 53.9 ± 29.5 months, and for melatonin 27.4 ± 24 months, p = 0.13) and there were no differences in treatment retention, with 28% of melatonin and 22% of clonazepam-treated patients discontinuing treatment (p = 0.43).ConclusionsMelatonin and clonazepam were each reported to reduce RBD behaviors and injuries and appeared comparably effective in our naturalistic practice experience. Melatonin-treated patients reported less frequent adverse effects than those treated with clonazepam. More effective treatments that would eliminate injury potential and evidence-based treatment outcomes from prospective clinical trials for RBD are needed.     

An observational clinical and video-polysomnographic study of the effects of clonazepam in REM sleep behavior disorder

ObjectiveTo analyze the differences in sleep structure and nocturnal motor activity between drug-free REM sleep behavior disorder (RBD) patients and those under therapy with clonazepam, and to evaluate the long-term longitudinal changes under continued therapy with clonazepam.MethodsFifty-seven consecutive iRBD patients were recruited (52 men and 5 women, mean age 68.8 ± 6.03 years). Forty-two patients were not taking any medication at the time of the evaluation (iRBD − Clo) while 15 were taking clonazepam (0.5–1 mg) at bedtime (iRBD + Clo). The Clinical Global Impression-Severity (CGI-S) scale was obtained. Sleep was video-polysomnographically recorded and the RBD severity scale (RBDSS) obtained. The chin EMG amplitude was quantitatively assessed and the Atonia Index computed.ResultsDisease duration was significantly longer in iRBD + Clo patients who also showed a lower rate of stage shifts, higher sleep efficiency and lower percentage of wakefulness after sleep onset and of sleep stage 1, and an increased percentage of sleep stage 2. The longitudinal long-term follow up study in a subgroup of 13 patients showed moderately increased total sleep time, sleep efficiency, sleep stage 2, slow-wave sleep and decreased wakefulness after sleep onset and sleep stage 1, under clonazepam treatment. The CGI scale clearly tended to improve after treatment, but no common trend was evident for RBDSS or Atonia Index.ConclusionsThis study provides evidence of important objective effects of clonazepam on NREM sleep in RBD; this data might be very important for the development of new and effective treatments for this condition.     

Clinical manifestations of Parkinson disease and the onset of rapid eye movement sleep behavior disorder

ObjectiveTo identify whether the presence and/or timing of rapid eye movement (REM) sleep behavior disorder (RBD) onset were associated with differences in clinical features and sleep parameters of Parkinson disease (PD).MethodsIn all, 112 PD patients were enrolled and all underwent extensive clinical evaluations and video-polysomnography (PSG). Clinical features and PSG parameters were compared in PD patients with (PD + RBD) or without (PD − RBD) RBD, RBD preceding (RBD > PD), or not (PD ⩾ RBD) PD onset.ResultsSixty-three of the 112 PD patients were affected by RBD. Adjusted for age, gender, education, body mass index (BMI), levodopa equivalent daily dose (LED) and PD duration, PD + RBD patients had higher Hoehn & Yahr stage, higher scores for UPDRS parts I, II and III, more dyskinesia, higher ratio of axial/limb manifestations, and more hallucinations. Their cognitive and quality-of-life status was significantly lower (all P < 0.05). For PSG, PD + RBD patients exhibited higher percentages of phasic and tonic EMG activities, lower apnea hypopnea (AHI) and oxygen desaturation index (ODI), and less time in arterial oxygen saturation (SaO₂) <90% during REM sleep (all P < 0.05). PD ⩾ RBD (n = 22) patients did not significantly differ from RBD > PD (n = 41) patients in clinical manifestations, whereas the PD ⩾ RBD subgroup had significantly higher UPDRS part I score, lower PDQ score and lower AHI during REM than the PD − RBD group (all P < 0.05), but not RBD > PD subgroup. Correlation analysis showed that worse cognition was associated with shorter interval of RBD preceding PD onset (r = 0.297, P = 0.018), but not RBD duration (P = 0.202).ConclusionsClinical manifestations of PD may vary depending on the presence and timing of RBD onset. These findings are compatible with the hypothesis that RBD may be a marker of complex subtypes of PD.     

REM and NREM sleep-state distribution of respiratory events in habitually snoring school-aged community children

BackgroundStudies ascribe different functions to rapid eye movement (REM) and non-rapid eye movement (NREM) sleep, such that their disruption could result in discrepant clinical outcomes. Although sleep architecture is globally preserved in children with obstructive sleep apnoea (OSA), it is considered to be an REM sleep REMS disorder. Furthermore, body position during sleep affects the occurrence of respiratory events, while the presence of obesity has been claimed to affect sleep-state distribution of respiratory disturbance.MethodsTo explore the distribution of respiratory events during REMS and NREM sleep NREMS and its potential predictors, a cross-sectional analysis of 335 overnight sleep studies in snoring children from the community was conducted. The ratio of REMS to NREMS respiratory events was compared, and potential associations were assessed using general linear modelling (GLM).ResultsChildren were 7.3 ± 1.2 years old and had a body mass index (BMI) z-score of 1.0 ± 1.3. The obstructive apnoea–hypopnea index (OAHI) was 1.7 ± 3 and 45.8% of children had an apnoea–hypopnea index (AHI) >1 h^?1 total sleep time (TST). Obstructive respiratory events were 3.8 times more likely in REMS (2.0 h^?1) than NREMS (0.5 h^?1), and the GLM revealed distinctive predictive associations for the apnoeic and hypopneic indices separately, and for body position, the latter indicating that the REMS/NREMS distribution of respiratory events depends on body position.ConclusionObstructive respiratory events are predominantly, albeit not exclusively, present in REMS in school-aged children. NREMS respiratory events are more likely in the presence of lower oxyhaemoglobin saturations during event, side body position and in African–American children. However, REMS dominance is not affected by either BMI z-score or obesity. Our findings suggest that incorporating comprehensive respiratory event profiles of children may enhance our understanding of the pathophysiology and adverse outcomes in the context of paediatric OSA.     

Comparison between an automatic and a visual scoring method of the chin muscle tone during rapid eye movement sleep

ObjectiveTo compare two different methods, one visual and the other automatic, for the quantification of rapid eye movement (REM) sleep without atonia (RSWA) in the diagnosis of REM sleep behavior disorder (RBD).MethodsSeventy-four RBD patients (mean age, 62.14 ± 9.67 years) and 75 normal controls (mean age, 61.04 ± 12.13 years) underwent one night video-polysomnographic recording. The chin electromyogram (EMG) during REM sleep was analyzed by means of a previously published visual method quantifying the percentage of 30 s epochs scored as tonic (abnormal, ⩾30%) and that of 2 s mini-epochs containing phasic EMG events (abnormal, ⩾15%). For the computer quantitative analysis we used the automatic scoring algorithm known as the atonia index (abnormal, <0.8). The percentage correct classification, sensitivity, specificity, and Cohen kappa were calculated.ResultsThe atonia index correctly classified 82.6% of subjects, similar to the percentage of correct classifications with individual components of the visual analysis (83.2% each for tonic and phasic), and the combined visual parameters (85.9%). The sensitivity and specificity of automatic analysis (84% and 81%) was similar to the combined visual analysis (89% and 83%). The correlation coefficient between the automatic atonia index and the percentage of visual tonic EMG was high (r = −0.886, P < 0.00001), with moderately high correlation with the percentage of phasic EMG (r = −0.690, P < 0.00001). The agreement between atonia index and the visual parameters (individual or combined) was approximately 85% with Cohen’s kappa, ranging from 0.638 to 0.693.ConclusionSensitivity, specificity, and correct classifications were high with both methods. Moreover, there was general agreement between methods, with Cohen’s kappa values in the ‘good’ range. Given the considerable practical advantages of automatic quantification of REM atonia, automatic quantification may be a useful alternative to visual scoring methods in otherwise uncomplicated polysomnograms.     

The discrepancy between actigraphic and sleep diary measures of sleep in adolescents

ObjectiveTo explore the discrepancy between sleep diary and actigraphic measures of sleep in adolescents and to ascertain whether these discrepancies may vary according to characteristics of the participant.MethodsParticipants were 385 adolescents aged 13–18 years (X = 15.6, standard deviation [SD] = 0.95; 60% male) from eight high schools in South Australia. Adolescents completed the School Sleep Habits Survey and Pediatric Daytime Sleepiness Scale during class time, followed by an 8-day sleep diary and wrist actigraphy. The Flinders Fatigue Scale was completed on the final day of the study. Parents completed a sleep, medical, education, and family history survey.ResultsActigraphic estimates of wake after sleep onset (WASO) were substantially greater than sleep diary estimates (74 min actigraphy vs. 7 min sleep diary) and actigraphic estimates of total sleep time were substantially less than sleep diary and parent report (6 h 51 min actigraphy vs. 8 h 16 min sleep diary vs. 8 h 51 parent report). Actigraphy displayed no significant relationship with daytime functioning and weak relationships with concomitantly recorded sleep diary variables. Sex and puberty-related differences in actigraphic scoring were found, with more WASO and less sleep scored in boys compared to girls and more WASO scored amongst pubertally-mature boys than boys of less advanced pubertal development.ConclusionsThere may be differences in the sleep of adolescents that result in less actigraphic total sleep scored than perceived, particularly in boys, possibly because of increased sleep motor activity in adolescents that actigraphic algorithms score as wake. This is a significant concern that requires further examination with polysomnography.     

Effects of long-term use of clonazepam on nonrapid eye movement sleep patterns in rapid eye movement sleep behavior disorder

ObjectiveWe aim to analyze in detail the characteristics of nonrapid eye movement (NREM) sleep in drug-free patients with idiopathic rapid eye movement sleep behavior disorder (iRBD). We compare drug-free iRBD patients to both normal controls and drug-free patients with narcolepsy/RBD and evaluate the changes following the long-term use of bedtime clonazepam.Participants and methodsForty-six participants were recruited: 15 with iRBD (13 men, 2 women; mean age, 65.8 ± 4.39 years), 13 with narcolepsy/RBD (10 men, 3 women; mean age, 63.0 ± 6.73 years), and 18 normal controls (10 men, 8 women; mean age 69.4 ± 7.72 years). Sleep was video polysomnographically recorded and the RBD severity scale (RBDSS) was obtained. Chin electromyography (EMG) amplitude was quantitatively assessed and the atonia index was computed. Additionally, NREM sleep instability was evaluated using an automatic quantitative analysis. Participants with iRBD were re-evaluated after 2.75 ± 1.62 years of regular therapy with 0.5 to 1-mg clonazepam at bedtime.ResultsSlow transient electroencephalography (EEG) events were increased in iRBD and decreased in narcolepsy/RBD, while fast transient events decreased in iRBD and increased in narcolepsy/RBD. During rapid eye movement (REM) sleep the atonia index was reduced in both iRBD and narcolepsy/RBD groups and during NREM sleep atonia index was increased in iRBD participants, remaining low in narcolepsy/RBD participants. After long-term therapy with clonazepam, wakefulness after sleep onset was decreased together with an increase in both slow-wave sleep (SWS) and sleep stage 2, in which the latter reached statistical significance; sleep stages 1 and 2 instability significantly decreased and the duration of EEG transients also slightly but significantly decreased. Finally, chin tone was not modified by clonazepam.ConclusionsOur study confirms that clonazepam modifies some aspects of NREM sleep in iRBD participants with a decrease in its instability. Moreover, we also show that a complex modification of sleep chin atonia exists in these participants, which also involves NREM sleep; for iRBD more complex neuropathologic models encompassing REM sleep and NREM sleep mechanisms are needed.     

Rapid eye movement sleep behaviour disorder in young- and older-onset Parkinson disease: a questionnaire-based study

BackgroundRapid eye movement sleep behavior disorder (RBD) is common in Parkinson disease (PD).ObjectivesTo determine the frequency of clinically probable RBD (cpRBD) in young-onset (21 to ⩽40 years; YOPD) and older-onset PD (>40 years; OOPD) and characterize its pattern.MethodsA total of 156 patients with PD (YOPD-51, OOPD-105) were clinically examined and the presence of RBD was diagnosed using the minimal criteria for diagnosis of RBD (International Classification of Sleep Disorders, ICSD-1). RBD screening questionnaire based on the minimal criteria was used. The bed-partners were also interviewed with Mayo sleep questionnaire. Other scales included Unified Parkinson Disease Rating Scale part III (UPDRS III), Hoehn & Yahr stage, Mini Mental Status Examination, Pittsburgh Sleep Quality Index, Parkinson Disease Sleep Scale, Epworth Sleep Scale, Hamilton Anxiety Rating Scale and Hamilton Depression Rating Scale.ResultscpRBD was diagnosed in 30 (19.2%) patients, majority being OOPD rather than YOPD (86.7% vs 13.3%; P = 0.01). The frequency of RBD was significantly higher (P = 0.016) in OOPD (24.8%) compared to those with YOPD (7.8%). Most often (72.4%) RBD occurred after the onset of parkinsonian symptoms. RBD was independently associated with higher global PSQI scores, total ESS scores and total PDSS scores after adjusting for the effects of age, gender, Hoehn & Yahr stage and duration of illness.ConclusionsPatients with RBD were older with later-onset motor symptoms, a more advanced stage, poorer sleep quality, and more frequent daytime sleepiness. Older-onset PD had a higher frequency of RBD than young-onset PD.