Rapid eye movement sleep behavior disorder in treatment-naïve Parkinson disease patients

Objective

Rapid eye movement (REM) sleep behavior disorder (RBD) is a risk factor for dementia in Parkinson disease (PD) patients. The objectives of our study were to prospectively evaluate the frequency of RBD in a sample of treatment-naïve, newly diagnosed PD patients and compare sleep characteristics and cognition in RBD and non-RBD groups.

Methods

Fifty-seven newly diagnosed PD patients were consecutively recruited in a university medical center. All patients underwent two overnight polysomnography (PSG) sessions and were diagnosed with RBD according to the International Classification of Sleep Disorders, Second Revision criteria. Daytime sleepiness was measured in a multiple sleep latency test (MSLT). Cognition was assessed in a standard neuropsychologic examination.

Results

Seventeen PD patients (30%) met the criteria for RBD. The RBD patients and non-RBD patients did not significantly differ in mean age, gender ratio, disease duration, motor symptom subtype and severity, total sleep time, percentage of REM sleep, apnea–hypopnea index, mean oxygen saturation, and importantly cognitive performance. However, non-RBD patients had a significantly shorter mean daytime sleep latency than RBD patients (15 vs 18 min, respectively; P = .014).

Conclusion

A high frequency of RBD was found in our sample of 57 newly diagnosed PD patients. At this stage in the disease, RBD was not found to be associated with other sleep disorders or cognitive decline. Follow-up is needed to assess the risk for developing dementia in early-stage PD patients with RBD.     

Clinical markers of early nigrostriatal neurodegeneration in idiopathic rapid eye movement sleep behavior disorder

Background

Rapid eye movement sleep behavior disorder (RBD) is an early feature in α synucleinopathies and may precede other clinical manifestations of disease for several years. Olfactory dysfunction and mild motor abnormalities (MMAs) are highly prevalent in prodromal α synucleinopathies such as RBD and are suspected to be predictive neurodegenerative markers. Because both markers also are highly prevalent in the healthy elderly population, the discriminative value to detect an early neurodegenerative process is unclear.

Methods

We examined 28 patients with idiopathic RBD (iRBD) without manifest neurodegenerative disease to determine diagnostic accuracy of MMAs and olfactory dysfunction in identifying patients with early nigrostriatal degeneration in transcranial sonography (TCS) and ¹²³I-2β-carbomethoxy-3β-(4-iodophenyl)-N-(3-fluoropropyl)-nortropane single-photon emission computed tomography (¹²³I-FP-CIT-SPECT).

Results

Sixty-three percent of our participants showed MMAs which were strongly associated with abnormal TCS and ¹²³I-FP-CIT-SPECT findings. The discriminative value in detecting participants with early nigrostriatal degeneration was excellent (area under the receiver operating characteristic [ROC] curve, 0.84 [P ? .003] for TCS and 0.79 [P ? .066] for ¹²³I-FP-CIT-SPECT). Olfactory dysfunction was present in 78% of iRBD participants, but it was not linked with neuroimaging abnormalities or MMAs. Olfactory dysfunction did not discriminate participants with early nigrostriatal degeneration (area under the ROC curve, 0.54 [P ? .747] for TCS and 0.31 [P ? .225] for ¹²³I-FP-CIT-SPECT). Early RBD manifestation but no demographic (e.g., age, gender) or clinical characteristics of RBD (e.g., duration, severity of RBD) were associated with neuroimaging abnormalities in TCS and ¹²³I-FP-CIT-SPECT.

Conclusions

Unlike olfactory dysfunction, MMAs discriminate patients with early nigrostriatal degeneration in iRBD. Early RBD manifestation seems to be an additional risk factor which aggravates neurodegenerative risk.     

Psychosocial correlates of sleep quality and architecture in women with metastatic breast cancer

Background

Sleep disturbance is prevalent among women with metastatic breast cancer (MBC). Our study examined the relationship of depression and marital status to sleep assessed over three nights of polysomnography (PSG).

Methods

Women with MBC (N = 103) were recruited; they were predominately white (88.2%) and 57.8 ± 7.7 years of age. Linear regression analyses assessed relationships among depression, marital status, and sleep parameters.

Results

Women with MBC who reported more depressive symptoms had lighter sleep (e.g., stage 1 sleep; P < .05), less slow-wave sleep (SWS) (P < .05), and less rapid eye movement (REM) sleep (P < .05). Single women had less total sleep time (TST) (P < .01), more wake after sleep onset (WASO) (P < .05), worse sleep efficiency (SE) (P < .05), lighter sleep (e.g., stage 1; P < .05), and less REM sleep (P < .05) than married women. Significant interactions indicated that depressed and single women had worse sleep quality than partnered women or those who were not depressed.

Conclusion

Women with MBC and greater symptoms of depression had increased light sleep and reduced SWS and REM sleep, and single women had worse sleep quality and greater light sleep than married counterparts. Marriage was related to improved sleep for women with more depressive symptoms.     

Polysomnographic abnormalities in patients with vascular cognitive impairment-no dementia

Objectives

We aimed to investigate subjective sleep quality and polysomnographic sleep structure features in patients with vascular cognitive impairment-no dementia (VCIND).

Methods

Fifty-six patients with VCIND, 48 patients with simple stroke (without cognitive impairment), and 48 control subjects were included. The Pittsburgh Sleep Quality Index (PSQI) and polysomnography (PSG) were used to analyze their sleep characteristics. The Montreal Cognitive Assessment (MoCA) was conducted to assess mental state.

Results

Patients with VCIND had higher PSQI scores compared with control subjects and simple stroke patients (P < .01). PSG revealed that patients with VCIND or stroke were more likely to experience prolonged sleep latency (SL), decreased sleep efficiency (SE), increased arousal, and reduced deep sleep and rapid eye movement (REM) sleep than controls. Patients with VCIND had significantly longer SL, increased periodic leg movements in sleep (PLMS), decreased SE, and increased arousal and sleep fragmentation compared to patients with simple stroke (P < .05). In VCIND patients, a significant positive correlation was found between SE and MoCA scores (r = 0.632; P < .001), though PSQI, SL, and arousal index were significantly negatively associated with MoCA scores (r = −0.787, −0.740, −0.772, respectively; P < .001 for all).

Conclusions

VCIND patients had different abnormal sleep features, including decreased SE, increased PLMS, and prolonged SL and sleep fragmentation. Abnormal sleep in VCIND may be associated with cognitive impairment.     

Electrical stimulation of the rostral ventrolateral medulla promotes wakefulness in rats

Objectives

Previous studies suggest that central sympathetic activity might carry information on wakefulness, so we tested the hypothesis that direct activation of the rostral ventrolateral medulla (RVLM), a well-studied sympathetic vasomotor center, promotes wakefulness.

Methods

A bipolar stimulating electrode was implanted in the right RVLM of Wistar-Kyoto rats or in a brainstem control site. Bioelectrical signals were recorded using a telemetry system. The experiment comprised a baseline session and a 6-h electrical stimulation session (50 μA, 50 Hz for 3 min every 20 min). Sleep–wake stages were defined by the electroencephalogram (EEG) and electromyogram (EMG) as active waking (AW), nonrapid eye movement (NREM) sleep, and rapid eye movement (REM) sleep. Autonomic function was assessed using cardiovascular variability analysis.

Results

During the RVLM stimulation session, AW time increased from 38.48 ± 5.82 to 99.91 ± 8.23 min compared with baseline (P < .001), while REM sleep was decreased from 110.10 ± 4.91 to 50.74 ± 13.01 min (P = .004). Analysis of the RVLM stimulation bouts delivered during NREM sleep showed a significantly higher probability of awakening; it also showed that the latency to arousal was significantly shorter than the latency for 10% blood pressure (BP) increase (1.50 ± 0.30 vs 7.42 ± 1.83 s; P = .009).

Conclusions

Our findings show that direct stimulation of the RVLM promotes wakefulness, suggesting that sleep disturbance may result from central sympathetic activation.     

Interpersonal distress is associated with sleep and arousal in insomnia and good sleepers

Objective

The interpersonal environment is strongly linked to sleep. However, little is known about interpersonal distress and its association with sleep. We examined the associations among interpersonal distress, objective and subjective sleep in people with and without insomnia.

Methods

Participants in this cross-sectional observational study included men and women with insomnia (n = 28) and good sleeper controls (n = 38). Interpersonal distress was measured with the Inventory of Interpersonal Problems. Sleep parameters included insomnia severity, self-reported presleep arousal, and sleep quality; and polysomnographically-assessed sleep latency (SL), total sleep time (TST), wake after sleep onset (WASO), percent delta (stage 3 + 4 NREM), percent REM, and EEG beta power. Hierarchical linear regression was used to assess the relationship between distress from interpersonal problems and sleep and the extent to which relationships differed among insomnia patients and controls.

Results

More interpersonal distress was associated with more self-reported arousal and higher percentage of REM. More interpersonal distress was associated with greater insomnia severity and more cognitive presleep arousal for individuals with insomnia, but not for controls. Contrary to expectations, interpersonal distress was associated with shorter sleep latency in the insomnia group. Results were attenuated, but still significant, after adjusting for depression symptoms.

Conclusion

Distress from interpersonal problems is associated with greater self-reported arousal and higher percent REM. Individuals with insomnia who report more distress from interpersonal problems have greater insomnia severity and cognitive presleep arousal, perhaps due to rumination. These findings extend our knowledge of the association between interpersonal stressors and sleep. Assessment and consideration of interpersonal distress could provide a novel target for insomnia treatment.     

Electroencephalogram slowing in rapid eye movement sleep behavior disorder is associated with mild cognitive impairment

Background

Idiopathic rapid eye movement (REM) sleep behavior disorder (iRBD) is a well-documented risk factor for synucleinopathies such as Parkinson disease (PD) and dementia with Lewy bodies (DLB). Moreover, approximately 50% of iRBD patients have mild cognitive impairment (MCI). The purpose of our study was to investigate waking electroencephalogram (EEG) abnormalities specific to iRBD patients with MCI.

Methods

Forty-two polysomnographically confirmed iRBD patients, including 23 iRBD [+]MCI patients 19 patients without MCI (iRBD [−]MCI), and 37 healthy subjects participated in the study. All participants underwent a complete neuropsychologic assessment for MCI diagnosis and a waking quantitative EEG recording.

Results

iRBD [+]MCI patients had a higher slow-to-fast frequency ratio than iRBD [−]MCI patients and controls in the parietal, temporal, and occipital regions. iRBD [+]MCI patients also had higher relative θ power in the parietal, temporal, and occipital regions and lower relative α power in the occipital region compared to iRBD [−]MCI patients and controls. Moreover, iRBD [+]MCI patients had higher relative θ power in the frontal and central areas and lower relative β power in the central, parietal, and temporal regions compared to controls. The dominant occipital frequency also was slower in iRBD [+]MCI patients compared to controls. No between-group differences were observed between iRBD [−]MCI patients and controls.

Conclusion

In iRBD patients, only those with concomitant MCI showed waking EEG slowing in the posterior cortical regions, providing a potential marker for an increased risk for developing DLB or PD.     

Difference in severity of sleep apnea in patients with rapid eye movement sleep behavior disorder with or without parkinsonism

ObjectiveRapid eye movement sleep behavior disorder (RBD) is a common sleep disturbance in patients with neurodegenerative disorders. We aimed to compare sleep parameters among the different types of RBD patients.MethodsA total of 122 patients with dream enactment behavior were screened. Of these, 92 patients who were diagnosed with RBD by polysomnography were included in this study. Enrolled patients with RBD were classified into four groups based on the following diagnoses: idiopathic RBD (iRBD); RBD with Parkinson disease (PD-RBD); multiple system atrophy (MSA) with RBD (MSA-RBD); and dementia with Lewy bodies (DLB) with RBD (DLB-RBD). Various clinical and polysomnographic parameters were compared.ResultsAmong the 92 patients with RBD, 35 had iRBD, 25 had PD-RBD, 17 had MSA-RBD, and 15 had DLB-RBD. The mean apnea−hypopnea index of atypical parkinsonism with RBD (AP-RBD) group was 16.2 ± 17.7 events/h (MSA-RBD, 14.0 ± 16.6; DLB-RBD, 18.8 ± 19.1), which was significantly higher than the other groups (p < 0.05). The proportion of patients with 100% supine sleep in the AP-RBD group (44%) was higher than that in the iRBD group (14%; p = 0.030). The proportion of OSA with 100% supine sleep position was significantly higher in the MSA-RBD and DLB-RBD groups than in the iRBD group (p = 0.042 and p = 0.029, respectively).ConclusionOur study demonstrated that patients in the MSA-RBD and DLB-RBD groups had a tendency to sleeping in the supine position and a higher vulnerability to OSA compared to other RBD groups. Further cohort studies are needed to evaluate the influence of these factors on the development of parkinsonism.     

The relationship between actigraphically defined sleep disturbance and REM sleep behaviour disorder in Parkinson's Disease

Aim

In this study, we sought to evaluate the utility of actigraphy for examining symptoms of rapid eye movement sleep behaviour disorder (RSBD).

Methods

Twenty-two patients with idiopathic Parkinson's Disease (mean age = 63.4 years, SD = 7.5) underwent neurological assessment and completed sleep diaries, self-report sleep questionnaires and 2-weeks of actigraphy. They also completed the rapid eye movement sleep behavior disorder questionnaire and were classified as screening negative (RSBD−, n = 9) or positive (RSBD+, n = 13) for RSBD according to published criteria. Key outcome data were the number of wake bouts and duration of arousals during the sleep interval as determined by actigraphy.

Results

Patients classified as RSBD+ demonstrated a higher number of wake bouts than those who were RSBD− (p = 0.011).

Conclusions

These results suggest that actigraphy may be a viable tool to assist in the early identification of RSBD. In turn, this could guide early intervention approaches.     

Treatment of sleep disorders may improve fatigue in multiple sclerosis

Objective

In a previous polysomnographic cross-sectional study we found a significant relationship between sleep disorders and multiple sclerosis (MS) related fatigue. The purpose of this open follow-up observation was to compare the impact of treatment of sleep disorders on MS related fatigue measured with the Modified Fatigue Impact Scale (MFIS).

Methods

Non-randomized follow-up observation: treated versus untreated patients, subgroups according to compliance with sleep medical treatment recommendations (univariate, multivariate analysis, multiple logistic regression). 66 MS patients were followed after polysomnography, 49 patients with relevant sleep disorders and 17 without.

Results

Mean MFIS scores decreased from 41.2 to 26.2 (p = 0.025) in patients with good compliance (GC; n = 18), from 42.4 to 32.1 (p = 0.12) in patients with moderate compliance (MC; n = 12), and from 41.6 to 35.5 (p = 0.17) in non-compliant patients (NC; n = 17). Mean MFIS values increased in patients without sleep disorders from 22.9 to 25.4 (NSD; n = 12, p = 0.56). In multiple logistic regression, treatment of sleep disorders predicted decrease of MFIS-values (GC versus NSD odds ratio 13.4; p = 0.015; 95% confidence interval (CI) 1.7–107.2, MC versus NSD odds ratio 13.8; p = 0.028; 95% CI 1.3–143.3).

Conclusions

Sleep medical treatment may improve MS related fatigue when patients adhere to treatment recommendations.     

Comparison of polysomnographic data in age-, sex- and Axis I psychiatric diagnosis matched HIV-seropositive and HIV-seronegative Insomnia Patients

Objective

There is a high prevalence of insomnia in HIV-seropositive patients. Insomnia is associated with poorer disease outcomes, cognitive impairment and HIV-associated dementia. However there is limited data characterizing the type of sleep disturbances, and the cause. Previous studies report conflicting results, and observed changes in the distribution of REM and SWS were hypothesized to result from co-morbid mood disorders, although this is not established. We carried out this study to determine if there are differences in polysomnographic (PSG) sleep data in age-, sex- and Axis I diagnoses- matched HIV-seropositive and HIV-seronegative patients.

Methods

Eighteen HIV-seropositive insomniacs were matched to HIV-seronegative insomniacs based on age, sex and Axis I diagnoses. Participants spent 2 consecutive nights in a sleep lab recording of PSG data.

Results

Multivariate analysis revealed an overall significant match-by-variable interaction (p = 0.0126). Follow-up analysis show that compared to HIV-seronegative insomnia controls, HIV-seropositive insomniacs have significantly longer SOL, 8% decreased sleep efficiency, and 8–10% decreased time spent in REM sleep (p’s < 0.05).

Conclusion

This study provides preliminary evidence that even after accounting for differences in age, sex and psychiatric diagnoses, HIV-seropositive patients with insomnia have significantly worse sleep than HIV-seronegative patients with insomnia.

Significance

Unlike what previous authors have proposed, our results do not support the view that comorbid psychiatric disorders like depression are responsible for the observed differences in PSG findings and the greater incidence of insomnia, in HIV-seropositive patients when compared with other groups of insomnia patients. This suggests the presence of other etiologies including neuronal damage, psychosocial stressors, or comorbid medical conditions. Further studies are needed to determine the extent to which these play a role in insomnia in the HIV-seropositive population.     

Non-REM sleep EEG power distribution in fatigue and sleepiness

Objectives

The aim of this study is to contribute to the sleep-related differentiation between daytime fatigue and sleepiness.

Methods

135 subjects presenting with sleep apnea–hypopnea syndrome (SAHS, n = 58) or chronic fatigue syndrome (CFS, n = 52) with respective sleepiness or fatigue complaints and a control group (n = 25) underwent polysomnography and psychometric assessments for fatigue, sleepiness, affective symptoms and perceived sleep quality. Sleep EEG spectral analysis for ultra slow, delta, theta, alpha, sigma and beta power bands was performed on frontal, central and occipital derivations.

Results

Patient groups presented with impaired subjective sleep quality and higher affective symptom intensity. CFS patients presented with highest fatigue and SAHS patients with highest sleepiness levels. All groups showed similar total sleep time. Subject groups mainly differed in sleep efficiency, wake after sleep onset, duration of light sleep (N1, N2) and slow wave sleep, as well as in sleep fragmentation and respiratory disturbance. Relative non-REM sleep power spectra distributions suggest a pattern of power exchange in higher frequency bands at the expense of central ultra slow power in CFS patients during all non-REM stages. In SAHS patients, however, we found an opposite pattern at occipital sites during N1 and N2.

Conclusions

Slow wave activity presents as a crossroad of fatigue and sleepiness with, however, different spectral power band distributions during non-REM sleep. The homeostatic function of sleep might be compromised in CFS patients and could explain why, in contrast to sleepiness, fatigue does not resolve with sleep in these patients. The present findings thus contribute to the differentiation of both phenomena.     

Effects of different sleep deprivation protocols on sleep perception in healthy volunteers

Objectives

To investigate whether different protocols of sleep deprivation modify sleep perception.

Methods

The effects of total sleep deprivation (TD) and selective rapid eye movement (REM) sleep deprivation (RD) on sleep perception were analyzed in normal volunteers. Thirty-one healthy males with normal sleep were randomized to one of three conditions: (i) normal uninterrupted sleep; (ii) four nights of RD; or (iii) two nights of TD. Morning perception of total sleep time was evaluated for each condition. Sleep perception was estimated using total sleep time (in hours) as perceived by the volunteer divided by the total sleep time (in hours) measured by polysomnography (PSG). The final value of this calculation was defined as the perception index (PI).

Results

There were no significant differences among the three groups of volunteers in the total sleep time measured by PSG or in the perception of total sleep time at baseline condition. Volunteers submitted to RD exhibited lower sleep PI scores as compared with controls during the sleep deprivation period (P < 0.05). Both RD and TD groups showed PI similar to controls during the recovery period.

Conclusion

Selective REM sleep deprivation reduced the ability of healthy young volunteers to perceive their total sleep time when compared with time measured by PSG. The data reinforce the influence of sleep deprivation on sleep perception.     

Estimation of sleep disturbances using wrist actigraphy in patients with postural tachycardia syndrome

Study objectives

Patients with postural tachycardia syndrome (POTS) commonly complain of fatigue, unrefreshing sleep, daytime sleepiness and diminished quality of life. The study objective was to assess sleep quality in POTS patients using wrist actigraphy.

Design

Prospective study with control group.

Methods

Patients with POTS (n = 36) and healthy subjects (n = 36) completed a detailed sleep log and actigraphy for 7 days.

Results

Compared with healthy subjects, POTS patients have more self-reported problems including days with restless sleep (53 ± 30% vs. 21 ± 20%; P < 0.001) and tiredness (75 ± 23% vs. 39 ± 27%; P < 0.001). Using actigraphy, POTS patients have lower sleep efficiency (73 ± 13% vs. 79 ± 6%; P = 0.01). Actigraphy determined sleep onset latency (SOL) did not vary significantly in the two groups, but subjective SOL was higher in POTS patient (56 ± 66 min vs. 13 ± 9 min; P = 0.001). In POTS patients, there was a significant correlation between subjective complaints of tiredness and actigraphic sleep efficiency (Rs = − 0.36; R² = 0.15; P = 0.01), significant correlations between actigraphic SOL and upright norepinephrine levels (P = 0.040), and between wake after sleep onset and standing heart rate (P = 0.02).

Conclusions

POTS patients have more sleep-related symptoms and poor sleep efficiency. The pattern of subjective vs. objective SOL mismatch is suggestive of sleep-state misperception. High norepinephrine correlated with actigraphic SOL, and this activation of the stress system may contribute significantly to a hyperarousal state with consequent insomnia, poor mental and physical health in POTS patients.     

Poor sleep quality and resistant hypertension

Objectives

We aimed to determine the relationship between sleep quality and treatment-resistant hypertension (RH).

Methods

In our cross-sectional cohort study, 270 consecutive essential hypertensive patients were recruited at the Outpatient Hypertension Unit, University of Pisa, Italy. The Pittsburgh Sleep Quality Index (PSQI), Beck Depression Inventory (BDI), and State-Trait Anxiety Inventory (STAI-Y2) were administered to all subjects. RH was defined as office blood pressure (BP) >140/90 mmHg with three or more antihypertensive drugs or controlled BP with four or more drugs. Poor sleep quality was defined as PSQI >5, depressive symptoms as BDI >10, and trait anxiety as STAI-Y2 >40. Patients with other sleep disorders were excluded.

Results

Complete data were available for 222 patients (50.9% men; mean age, 56.6 ± 12.5 y; RH, 14.9%). Poor sleep quality had a prevalence of 38.2% in the overall population. RH was associated with poor sleep quality, increased sleep latency and reduced sleep efficiency. No significant relationship was found between RH and short sleep duration or depressive symptoms and trait anxiety. Poor sleep quality was more prevalent in resistant vs nonresistant hypertensive women (70.6% vs 40.2%; P = .02) but not in resistant vs nonresistant men (43.8% vs 29.2%; P = .24). In women poor sleep quality was an independent predictor of RH, even after adjustment for cardiovascular and psychiatric comorbidities (odds ratio [OR], 5.3 [confidence interval {CI}, 1.1–27.6), explaining 4.7% of its variance. In men age, diabetes mellitus (DM), and obesity were the only variables associated with RH.

Conclusions

Poor sleep quality is significantly associated with resistance to treatment in hypertensive women, independent of cardiovascular and psychiatric confounders.     

Familiality and clinical outcomes of sleep disturbances in major depressive and bipolar disorders

Objective

Sleep disturbances are frequently observed in major depressive (MDD) and bipolar disorder (BD). This study reported sleep profiles of patients and their relatives versus controls, and examined the familiality of sleep features in mood disorder families. We also evaluated the influences of sleep disturbance on patients' quality of life (QOL), functional impairment, and suicidality.

Methods

We recruited 363 BD and 157 MDD patients, 521 first-degree relatives, and 235 healthy controls, which completed a diagnostic interview, Pittsburgh Sleep Quality Index (PSQI), and QOL questionnaire. The magnitude of heritability of sleep features was calculated and familiality was evaluated by mixed regression models and intraclass correlation coefficient (ICC). The associations between sleep problems and clinical outcomes were examined using multiple regression models.

Results

More than three-quarters of mildly-ill patients were classified as “poor sleepers”. MDD patients had significantly worse sleep quality as compared to BD patients. Moderate but significant familial aggregation was observed in subjective sleep quality, sleep latency, disturbance, daytime dysfunction, and global score (ICC = 0.10–0.21, P < .05). Significant heritability was found in sleep quality (0.45, P < .001) and sleep disturbance (0.23, P < .001). Patients with good sleep quality had better QOL and less functional impairment (P < .05) than poor sleepers. Poor sleep quality and nightmares further increased the risk for suicidal ideation (OR_adj = 2.8) and suicide attempts (OR_adj = 1.9–2.8).

Conclusion

Subjectively measured sleep features demonstrated significant familiality. Poor sleep quality further impaired patients' daily function and QOL, in addition to increasing the risk of suicidality, and thus requires special attention in related clinical settings.     

Scoring accuracy of automated sleep staging from a bipolar electroocular recording compared to manual scoring by multiple raters

Objectives

Electroencephalography (EEG) assessment in research and clinical studies is limited by the patient burden of multiple electrodes and the time needed to manually score records. The objective of our study was to investigate the accuracy of an automated sleep-staging algorithm which is based on a single bipolar EEG signal.

Methods

Three raters each manually scored the polysomnographic (PSG) records from 44 patients referred for sleep evaluation. Twenty-one PSG records were scored by Rechtschaffen and Kales (R&K) criteria (group 1) and 23 PSGs were scored by American Academy of Sleep Medicine (AASM) 2007 criteria (group 2). Majority agreement was present in 98.4% of epochs and was used for comparison to automated scoring from a single EEG lead derived from the left and right electrooculogram.

Results

The κ coefficients for interrater manual scoring ranged from 0.46 to 0.89. The κ coefficient for the auto algorithm vs manual scoring by rater ranged from 0.42 to 0.63 and was 0.61 (group 1, κ = 0.61 and group 2, κ = 0.62) for majority agreement for all studies. The mean positive percent agreement across subjects and stages was 72.6%, approximately 80% for stages wake (78.3%), stage 2 sleep (N2) (80.9%), and stage 3 sleep (N3) (78.1%); the percentage slightly decreased to 73.2% for rapid eye movement (REM) sleep and dropped to 31.9% for stage 1 sleep (N1). Differences in agreement were observed based on raters, obstructive sleep apnea (OSA) severity, medications, and signal quality.

Conclusions

Our study demonstrated that automated scoring of sleep obtained from a single-channel of forehead EEG results in agreement to majority manual scoring are similar to results obtained from studies of manual interrater agreement. The benefit in assessing auto-staging accuracy with consensus agreement across multiple raters is most apparent in patients with OSA; additionally, assessing auto-staging accuracy limited disagreements in patients on medications and in those with compromised signal quality.     

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.     

Effect of low-intensity pure tone auditory stimulation on patients with rapid eye movement sleep behavior disorder

Objective: This study aimed to investigate the influence of low-intensity pure tone auditory stimulation on patients with rapid eye movement (REM), sleep behavior disorder (RBD), and attempt to identify a new method of RBD intervention.

Methods: Patients diagnosed with idiopathic RBD (iRBD) or symptomatic RBD (sRBD) were given auditory stimulation of low-intensity pure tones during their REM sleep. Sleep parameters including sleep process, sleep architecture as well as eye movements (EMs) frequency, and amplitude were recorded by polysomnography monitoring at pre-, intra-, and post-stimulation.

Results: Thirteen iRBD and 18 sRBD patients completed this study. Auditory stimulation significantly reduced the EMs frequency and amplitude in iRBD and sRBD patients (p < 0.05). In the iRBD group, the intra-stimulated FSL increased significantly than the pre-stimulated FSL (p < 0.05). After stimulation, patients had similar sleep latency (FSL), rapid eye movement sleep latency (RSL) and periodic limb movements in sleep (PLMS) compared with control. In the sRBD group, the intra-stimulated total sleep time, sleep efficiency was significantly increased, whereas the RSL and PLMS were significantly reduced compared with the pre-stimulated ones (all p < 0.05). The sRBD patients had similar time in bed, FSL and RBD episodes compared with control (all p < 0.05) in spite of significant difference before stimulation (all p < 0.05). However, the sleep architecture was not influenced by the stimulation despite the decrease in N3% in iRBD group (p < 0.05).

Conclusion: Low-intensity pure tone auditory stimulation may be a potentially effective intervention for RBD, especially for sRBD.     

Sociodemographic factors associated with sleep quality and sleep duration in adolescents from Santa Catarina,Brazil: what changed between 2001 and 2011?

Objective

We aimed to identify and compare the sociodemographic and economic factors associated with perceived sleep quality and sleep duration in high school students from Santa Catarina, Brazil (2001 and 2011).

Methods

Our study used a school-based, cross-sectional survey administered in 2001 and 2011 to high school students aged 15–19 years (n = 5028 in 2001; n = 6529 in 2011) enrolled in public schools in Santa Catarina, Brazil.

Results

The students responded to a questionnaire that asked about the number of hours slept on school days (insufficient, <8 h; sufficient, ?8 h), perceived sleep quality (adequate or poor), sociodemographic characteristics (gender, age, and area), economic factors (work and family income), and school-related variables (grade and shift). The prevalence of poor sleep quality and insufficient sleep increased by 31.2% and 45.9%, respectively, between 2001 and 2011. Remunerated employment, urban environment, male gender, and high family income were strongly associated with these outcomes.

Conclusions

There was a notable increase in insufficient sleep and the perception of poor sleep quality among the students in Santa Catarina in the last decade. Public policies are needed to ameliorate this situation, which has disastrous consequences for the health of adolescents.