REM sleep behavior disorder (RBD) is associated with neurodegenerative disease and particularly with the synucleinopathies. Convenience samples involving subjects with idiopathic RBD have suggested an increased risk of incident mild cognitive impairment (MCI), dementia (usually dementia with Lewy bodies) or Parkinson’s disease (PD). There is no data on such risk in a population-based sample.
Cognitively normal subjects aged 70–89 in a population-based study of aging who screened positive for probable RBD using the Mayo Sleep Questionnaire were followed at 15 month intervals. In a Cox Proportional Hazards Model, we measured the risk of developing MCI, dementia, PD among the exposed (pRBD+) and unexposed (pRBD−) cohorts.
Forty-four subjects with pRBD+ at enrollment (median duration of pRBD features was 7.5 years), and 607 pRBD− subjects, were followed prospectively for a median of 3.8 years. Fourteen of the pRBD+ subjects developed MCI and one developed PD (15/44=34% developed MCI / PD); none developed dementia. After adjustment for age, sex, education, and medical comorbidity, pRBD+ subjects were at increased risk of MCI / PD [Hazard Ratio (HR) 2.2, 95% Confidence Interval (95%CI) 1.3 – 3.9; p=0.005]. Inclusion of subjects who withdrew from the study produced similar results, as did exclusion of subjects with medication-associated RBD. Duration of pRBD symptoms did not predict the development of MCI / PD (HR 1.05 per 10 years, 95%CI 0.84 – 1.3; p=0.68).
In this population-based cohort study, we observed that pRBD confers a 2.2-fold increased risk of developing MCI / PD over four years.
sleep disorders; parasomnias; dementia; Alzheimer’s disease; dementia with Lewy bodies; parkinsonism; synuclein
REM sleep behavior disorder (RBD) is a parasomnia characterized by loss of muscle atonia during REM sleep that results in motor behaviors. Diagnosis of RBD involves a clinical interview in which history of dream enactment behaviors is elicited and a subsequent overnight polysomnography (PSG) evaluation to assess for REM sleep without atonia (RWA) and/or observe motor behaviors during REM sleep. Therefore, the nature of RBD diagnosis involves both subjective and objective measurements that attempt to qualify and quantify the different diagnostic sub-criteria.
The primary aim of the current study was to identify and summarize the available clinical measurements that have been used for RBD assessment.
Two major online databases (MEDLINE and PsycInfo) were searched for articles developing, validating, or evaluating psychometric properties of the RBD diagnostic criteria or methods used for diagnosis. Studies of adult subjects (18+) that included sufficient psychometric data for validation were included.
Fifty-eight studies were found to meet review criteria. The objective measurements for assessment of RBD reviewed included visual electromygraphic (EMG) scoring methods, computerized EMG scoring methods, cardiac 123I-MIBG scintigraphy, actigraphy, behavioral classification and video analysis. Subjective measurements of RBD included interviews and questionnaires.
Sleep history may be sufficient for diagnosis of RBD in some populations. However, PSG is necessary for a definitive diagnosis. EMG scoring methods vary in definition used and there is no single accepted approach to scoring muscle activity. Additional validation studies are required for establishing cutoff scores for the different methods. Questionnaires were shown to be appropriate screening tools, yet further validation in different population is necessary.
Idiopathic REM sleep behavior disorder (RBD) may be the initial manifestation of synucleinopathies (Parkinson disease [PD], multiple system atrophy [MSA], or dementia with Lewy bodies [DLB]).
We used the Mayo medical records linkage system to identify cases presenting from 2002 to 2006 meeting the criteria of idiopathic RBD at onset, plus at least 15 years between RBD and development of other neurodegenerative symptoms. All patients underwent evaluations by specialists in sleep medicine to confirm RBD, and behavioral neurology or movement disorders to confirm the subsequent neurodegenerative syndrome.
Clinical criteria were met by 27 patients who experienced isolated RBD for at least 15 years before evolving into PD, PD dementia (PDD), DLB, or MSA. The interval between RBD and subsequent neurologic syndrome ranged up to 50 years, with the median interval 25 years. At initial presentation, primary motor symptoms occurred in 13 patients: 9 with PD, 3 with PD and mild cognitive impairment (MCI), and 1 with PDD. Primary cognitive symptoms occurred in 13 patients: 10 with probable DLB and 3 with MCI. One patient presented with primary autonomic symptoms, diagnosed as MSA. At most recent follow-up, 63% of patients progressed to develop dementia (PDD or DLB). Concomitant autonomic dysfunction was confirmed in 74% of all patients.
These cases illustrate that the α-synuclein pathogenic process may start decades before the first symptoms of PD, DLB, or MSA. A long-duration preclinical phase has important implications for epidemiologic studies and future interventions designed to slow or halt the neurodegenerative process.
= dementia with Lewy bodies;
= mild cognitive impairment;
= multiple system atrophy;
= Parkinson disease;
= PD with associated mild cognitive impairment;
= Parkinson disease dementia;
= REM sleep behavior disorder.
Rapid eye movement (REM) sleep behavior disorder (RBD) is a parasomnia characterized by excessive muscle activity and undesirable motor events during REM sleep. RBD occurs in approximately 0.5% of the general population, with a higher prevalence in older men. RBD is a frequent feature of dementia with Lewy bodies (DLB), but is only rarely reported in Alzheimer’s disease. RBD is also a risk factor for α-synuclein-related diseases, such as DLB, Parkinson’s disease (PD), and multiple system atrophy. Therefore, RBD has major implications for the diagnosis and treatment of neurodegenerative disorders and for understanding specific neurodegeneration patterns. Several markers of neurodegeneration have been identified in RBD, including cognitive impairments such as deficits in attention, executive functions, learning capacities, and visuospatial abilities. Approximately 50% of RBD patients present mild cognitive impairment. Moreover, RBD is also associated with cognitive decline in PD.
sleep; cognition; elderly; REM sleep behavior disorder; mild cognitive impairment; Parkinson’s disease; dementia with Lewy bodies
Rapid eye movement (REM) sleep behavior disorder (RBD) is a parasomnia characterized by
repeated episodes of dream enactment behavior and REM sleep without atonia (RSWA) during
polysomnography recording. RSWA is characterized by increased phasic or tonic muscle activity seen
on polysomnographic electromyogram channels. RSWA is a requisite diagnostic feature of RBD, but may
also be seen in patients without clinical symptoms or signs of dream enactment as an incidental
finding in neurologically normal individuals, especially in patients receiving antidepressant
therapy. RBD may be idiopathic or symptomatic. Patients with idiopathic RBD often later develop
other neurological features including parkinsonism, orthostatic hypotension, anosmia, or cognitive
impairment. RSWA without clinical symptoms as well as clinically overt RBD also often occurs
concomitantly with the α-synucleinopathy family of neurodegenerative disorders, which
includes idiopathic Parkinson disease, Lewy body dementia, and multiple system atrophy. This review
article considers the epidemiology of RBD, clinical and polysomnographic diagnostic standards for
both RBD and RSWA, previously reported associations of RSWA and RBD with neurodegenerative disorders
and other potential causes, the pathophysiology of which brain structures and networks mediate
dysregulation of REM sleep muscle atonia, and considerations for the effective and safe management
REM sleep behavior disorder; REM sleep without atonia; Parasomnia; α-synucleinopathy; Parkinsonism; Neurodegeneration; Braak staging; Melatonin; Clonazepam; Treatment; Neuropsychological testing; Neurological disease
Rapid eye movement (REM) sleep behavior disorder (RBD) is a parasomnia manifested by vivid, often frightening dreams associated with simple or complex motor behavior during REM sleep. Patients appear to “act out their dreams,” in which the exhibited behaviors mirror the content of the dreams, and the dream content often involves a chasing or attacking theme. The polysomnographic features of RBD include increased electromyographic tone +/- dream enactment behavior during REM sleep. Management with counseling and pharmacologic measures is usually straight-forward and effective.
In this review, the terminology, clinical and polysomnographic features, demographic and epidemiologic features, diagnostic criteria, differential diagnosis, and management strategies are discussed. Recent data on the suspected pathophysiologic mechanisms of RBD are also reviewed. The literature and our institutional experience on RBD are next discussed, with an emphasis on the RBD-neurodegenerative disease association and particularly the RBD-synucleinopathy association. Several issues relating to evolving concepts, controversies, and future directions are then reviewed, with an emphasis on idiopathic RBD representing an early feature of a neurodegenerative disease and particularly an evolving synucleinopathy. Planning for future therapies that impact patients with idiopathic RBD is reviewed in detail.
REM sleep behavior disorder; parasomnia; synucleinopathy; neurodegenerative disease
Over 50% of persons with idiopathic REM sleep behavior disorder (RBD) will develop Parkinson disease (PD) or dementia. At present, there is no way to predict who will develop disease. Since polysomnography is performed in all patients with idiopathic RBD at diagnosis, there is an opportunity to analyze if baseline sleep variables predict eventual neurodegenerative disease.
In a longitudinally studied cohort of patients with idiopathic RBD, we identified those who had developed neurodegenerative disease. These patients were matched by age, sex, and follow-up duration to patients with RBD who remained disease-free and to controls. Polysomnographic variables at baseline (i.e., before development of neurodegenerative disease) were compared between groups.
Twenty-six patients who developed neurodegenerative disease were included (PD 12, multiple system atrophy 1, dementia 13). The interval between polysomnogram and disease onset was 6.7 years, mean age was 69.5, and 81% were male. There were no differences between groups in sleep latency, sleep time, % stages 2–4, % REM sleep, or sleep efficiency. However, patients with idiopathic RBD who developed neurodegenerative disease had increased tonic chin EMG activity during REM sleep at baseline compared to those who remained disease-free (62.7 ± 6.0% vs 41.0 ± 6.0%, p = 0.020). This effect was seen only in patients who developed PD (72.9 ± 6.0% vs 41.0 ± 6.0%, p = 0.002), and not in those who developed dementia (54.3 ± 10.3, p = 0.28). There was no difference in phasic submental REM EMG activity between groups.
In patients with REM sleep behavior disorder initially free of neurodegenerative disease, the severity of REM atonia loss on baseline polysomnogram predicts the development of Parkinson disease.
= Diagnostic and Statistical Manual of Mental Disorders, 4th edition;
= Parkinson disease;
= REM sleep behavior disorder.
Rapid eye movement (REM) sleep behavior disorder (RBD) is a sleep disorder that predominantly affects older adults, in which patients appear to be enacting their dreams while in REM sleep. The behaviors are typically violent, in association with violent dream content, so serious harm can be done to the patient or the bed-partner. The estimated prevalence in adults is 0.4–0.5%, but the frequency is much higher in certain neurodegenerative diseases, especially Parkinson's disease, Dementia with Lewy bodies, and multiple systems atrophy. RBD can occur in the absence of diagnosed neurologic diseases (the “idiopathic” form), although patients with this form of RBD may have subtle neurologic abnormalities and often ultimately develop a neurodegenerative disorder. Animal models and cases of RBD developing after brainstem lesions (pontine tegmentum, medulla) have led to the understanding that RBD is caused by a lack of normal REM muscle atonia and a lack of normal suppression of locomotor generators during REM. Clonazepam is used as first-line therapy for RBD and melatonin for second-line therapy, although evidence for both of these interventions comes from uncontrolled case series. Because the risk of injury to the patient or the bed-partner is high, interventions to improve the safety of the sleep environment are also often necessary. This review describes the epidemiology, pathophysiology, and treatment of RBD.
Background and Purpose
Sleep-related falling out of bed (SFOB), with its potential for significant injury, has not been a strong focus of investigation in Parkinson's disease (PD) to date. We describe the demographic and clinical characteristics of PD patients with and without SFOB.
We performed a retrospective analysis of 50 consecutive PD patients, who completed an REM sleep behavior disorder screening questionnaire (RBDSQ), questionnaires to assess for RBD clinical mimickers and questions about SFOB and resulting injuries. Determination of high risk for RBD was based on an RBDSQ score of 5 or greater.
Thirteen patients reported history of SFOB (26%). Visual hallucinations, sleep-related injury, quetiapine and amantadine use were more common in those patients reporting SFOB. Twenty-two patients (44%) fulfilled criteria for high risk for RBD, 12 of which (55%) reported SFOB. Five patients reported injuries related to SFOB. SFOB patients had higher RBDSQ scores than non-SFOB patients (8.2±3.0 vs. 3.3±2.0, p<0.01). For every one unit increase in RBDSQ score, the likelihood of SFOB increased two-fold (OR 2.4, 95% CI 1.3-4.2, p<0.003).
SFOB may be a clinical marker of RBD in PD and should prompt confirmatory polysomnography and pharmacologic treatment to avoid imminent injury. Larger prospective studies are needed to identify risk factors for initial and recurrent SFOB in PD.
Parkinson's disease; REM sleep behavior disorder; sleep disturbance; falls; sleep-related injury
Traumatic brain injury (TBI) is a common problem and leading causes of morbidity and mortality in the general population. Sleep disorders are a common finding after the acute and chronic phase of TBI. They result in daytime somnolence which in turn may lead to poor daytime performance, altered sleep-wake schedule, heightened anxiety, and poor individual sense of well-being, insomnia and depression. Studies underscore the importance of examining the architecture of sleep in TBI patients that can use as objective diagnostic or prognostic markers of injury. Posttraumatic hypersomnia, sleep apnea, narcolepsy, periodic limb movement disorder (PLMD), Insomnia and Parasomnia because of REM behavior disorder (RBD) are the most common sleep disorders in TBI patients.
The neuropathology associated with TBI will depend on the nature and location of the underlying injury. Sleep polysomnography (PSG) analyses may provide a somewhat crude biomarker of injury as an initial step in the diagnostic work-up. If abnormalities in the PSG are observed, more detailed electroencephalographic methods, using electrodes at multiple locations (frontal, temporal, occipital) could be further used to localize the site of the most severe lesions.
Additional research will be required to determine whether the location and severity of sleep PSG abnormalities can be used as a predictor for longer-term disability. The present study suggest that sleep measures may be a sensitive measure of brain injury after TBI and, in theory, could be used for determining the anatomy of brain injury.
Traumatic brain injuries, Polysomnography, Sleep disorders
The authors hypothesized that if locomotor drive increases along with rapid eye movement (REM) sleep without atonia in idiopathic REM sleep behavior disorder (RBD), then RBD patients would have greater corticomuscular coherence (CMC) values during REM sleep than at other sleep stages and than in healthy control subjects during REM sleep. To explore this hypothesis, we analyzed beta frequency range CMC between sensorimotor cortex electroencephalography (EEG) and chin/limb muscle EMG in idiopathic RBD patients. Eleven drug naive idiopathic RBD patients and 11 age-matched healthy control subjects were included in the present study. All participants completed subjective sleep questionnaires and underwent polysomnography for one night. The CMC value between EEGs recorded at central electrodes and EMGs acquired at leg and chin muscles were computed and compared by repeated measures analysis of variance (ANOVA). Sleep stages and muscle (i.e., chin vs. leg) served as within-subject factors, and group served as the between-subject factor. Repeated measures ANOVA revealed no significant main effect of group (F1,20 = 0.571, p = 0.458) or muscle (F1,20 = 1.283, p = 0.271). However, sleep stage was found to have a significant main effect (F2.067,41.332 = 20.912, p < 0.001). The interaction between group and sleep stage was significant (F2.067,41.332 = 3.438, p = 0.040). RBD patients had a significantly higher CMC value than controls during REM sleep (0.047 ± 0.00 vs. 0.052 ± 0.00, respectively, p = 0.007). This study reveals increased CMC during REM sleep in patients with RBD, which indicates increased cortical locomotor drive. Furthermore, this study supports the hypothesis that sufficient locomotor drive plays a role in the pathophysiology of RBD in addition to REM sleep without atonia.
REM sleep behavior disorder; pathophysiology; corticomuscular coherence; REM sleep without atonia
Rapid eye movement (REM) sleep behavior disorder (RBD) is characterized by loss of normal atonia during REM sleep, such that patients appear to act out their dreams. The most important implication of research into this area is that patients with idiopathic RBD are at very high risk of developing synuclein-mediated neurodegenerative disease (Parkinson's disease [PD], dementia with Lewy bodies [DLB], and multiple system atrophy), with risk estimates that approximate 40–65% at 10 years. Thus, RBD disorder is a very strong feature of prodromal synucleinopathy. This provides several opportunities for future research. First, patients with REM sleep behavior disorder can be studied to test other predictors of disease, which could potentially be applied to the general population. These studies have demonstrated that olfactory loss, decreased color vision, slowing on quantitative motor testing, and abnormal substantia nigra neuroimaging findings can predict clinical synucleinopathy. Second, prospectively studying patients with RBD allows a completely unprecedented opportunity to directly evaluate patients as they transition into clinical neurodegenerative disease. Studies assessing progression of markers of neurodegeneration in prodromal PD are beginning to appear. Third, RBD are very promising subjects for neuroprotective therapy trials because they have a high risk of disease conversion with a sufficiently long latency, which provides an opportunity for early intervention. As RBD research expands, collaboration between centers will become increasingly essential.
REM Sleep Behavior Disorder; Parkinson's disease; Dementia with Lewy bodies; prodromal
Background and purpose
Rapid eye movement (REM) sleep behavior disorder (RBD) is a parasomnia reflecting changes in the brain, but which specific neuronal networks are involved in human RBD pathogenesis has not yet been determined. To date, only one case of idiopathic RBD has undergone autopsy, in which “incidental Lewy body disease” was found. Due to the severe neuronal loss and gliosis in the substantia nigra (SN) and locus ceruleus (LC) in this case, degeneration of brainstem monoaminergic neurons was postulated as the underlying substrate for RBD. Additional cases of idiopathic RBD with neuropathologic examination may help clarify which key brainstem structures are involved.
Patient and methods
Case report with neuropathologic analysis.
A man with polysomnographically proven RBD (onset age 57 years), but no other neurologic signs or symptoms, underwent neuropathologic examination upon his death at age 72. Histopathologic analysis showed Lewy body disease, but no significant neuronal loss or gliosis was present in the SN or LC.
This case represents another example of Lewy body disease associated with RBD. The minimal degenerative changes in the SN and LC call into question the role of these nuclei in RBD, at least in our case. We suggest additional cases of idiopathic RBD undergo neuropathologic analyses to better delineate the neurologic substrate of this intriguing parasomnia.
REM sleep behavior disorder; parasomnia; Lewy bodies; Lewy body disease; synuclein
Increasing evidence provides a clear association between rapid eye movement sleep behavior disorders (RBD) and Parkinson’s disease (PD), but the clinical features that determine the co-morbidity of RBD and PD are not yet fully understood.
We evaluated the characteristics of nocturnal disturbances and other motor and non-motor features related to RBD in patients with PD and the impact of RBD on their quality of life. Probable RBD (pRBD) was evaluated using the Japanese version of the RBD screening questionnaire (RBDSQ-J).
A significantly higher frequency of pRBD was observed in PD patients than in the controls (RBDSQ-J ≥ 5 or ≥ 6: 29.0% vs. 8.6%; 17.2% vs. 2.2%, respectively). After excluding restless legs syndrome and snorers in the PD patients, the pRBD group (RBDSQ-J≥5) showed higher scores compared with the non-pRBD group on the Parkinson’s disease sleep scale-2 (PDSS-2) total and three-domain scores. Early morning dystonia was more frequent in the pRBD group. The Parkinson’s Disease Questionnaire (PDQ-39) domain scores for cognition and emotional well-being were higher in the patients with pRBD than in the patients without pRBD. There were no differences between these two groups with respect to the clinical subtype, disease severity or motor function. When using a cut-off of RBDSQ-J = 6, a similar trend was observed for the PDSS-2 and PDQ-39 scores. Patients with PD and pRBD had frequent sleep onset insomnia, distressing dreams and hallucinations. The stepwise linear regression analysis showed that the PDSS-2 domain “motor symptoms at night”, particularly the PDSS sub-item 6 “distressing dreams”, was the only predictor of RBDSQ-J in PD.
Our results indicate a significant impact of RBD co-morbidity on night-time disturbances and quality of life in PD, particularly on cognition and emotional well-being. RBDSQ may be a useful tool for not only screening RBD in PD patients but also predicting diffuse and complex clinical PD phenotypes associated with RBD, cognitive impairment and hallucinations.
Parkinson’s disease; Rapid eye movement sleep behavior disorder; Cognition; Quality of life; Nocturnal problems
To determine whether adding REM sleep behavior disorder (RBD) to the dementia with Lewy bodies (DLB) diagnostic criteria improves classification accuracy of autopsy-confirmed DLB.
We followed 234 consecutive patients with dementia until autopsy with a mean of 4 annual visits. Clinical diagnoses included DLB, Alzheimer disease (AD), corticobasal syndrome, and frontotemporal dementia. Pathologic diagnoses used the 2005 DLB consensus criteria and included no/low likelihood DLB (non-DLB; n = 136) and intermediate/high likelihood DLB (DLB; n = 98). Regression modeling and sensitivity/specificity analyses were used to evaluate the diagnostic role of RBD.
Each of the 3 core features increased the odds of autopsy-confirmed DLB up to 2-fold, and RBD increased the odds by 6-fold. When clinically probable DLB reflected dementia and 2 or more of the 3 core features, sensitivity was 85%, and specificity was 73%. When RBD was added and clinically probable DLB reflected 2 or more of 4 features, sensitivity improved to 88%. When dementia and RBD were also designated as probable DLB, sensitivity increased to 90% while specificity remained at 73%. The VH, parkinsonism, RBD model lowered sensitivity to 83%, but improved specificity to 85%.
Inclusion of RBD as a core clinical feature improves the diagnostic accuracy of autopsy-confirmed DLB.
Compare the frequency of REM sleep behavior disorder (RBD) and excessive daytime sleepiness (EDS) in Parkinson’s disease (PD), restless legs syndrome (RLS), essential tremor (ET), and control subjects.
Subjects enrolled in a longitudinal clinicopathologic study, and when available an informant, completed the Mayo Sleep Questionnaire, which asks “Have you ever been told that you act out your dreams?”, and the Epworth Sleepiness Scale (ESS).
Probable RBD (based on informant response to the questionnaire) was much more frequent in PD (34/49, 69%, p<0.001) than in RLS (6/30, 20%), ET (7/53, 13%), or control subjects (23/175, 13%), with an odds ratio of 11 for PD compared to controls. The mean ESS and the number of subjects with an ESS ≥ 10 was higher in PD (29/60, 48%, p<0.001) and RLS (12/39, 31%, p<0.001) compared with ET (12/93, 13%) and Controls (34/296, 11%).
Probable RBD is much more frequent in PD with no evidence to suggest an increase in either RLS or ET. Given the evidence that RBD is a synucleinopathy, the lack of an increased frequency of RBD in subjects with ET or RLS suggests the majority of ET and RLS subjects are unlikely to be at increased risk for developing PD.
Parkinson’s disease; REM sleep behavior disorder; essential tremor; restless legs syndrome; excessive daytime sleepiness
Idiopathic REM sleep behavior disorder (RBD) is a potential preclinical marker for the development of neurodegenerative diseases, particularly Parkinson disease (PD) and Lewy body dementia. However, the long-term risk of developing neurodegeneration in patients with idiopathic RBD has not been established. Obtaining an accurate picture of this risk is essential for counseling patients and for development of potential neuroprotective therapies.
We conducted a follow-up study of all patients seen at the sleep disorders laboratory at the Hôpital du Sacré Coeur with a diagnosis of idiopathic RBD. Diagnoses of parkinsonism and dementia were defined according to standard criteria. Survival curves were constructed to estimate the 5-, 10-, and 12-year risk of developing neurodegenerative disease.
Of 113 patients, 93 (82%) met inclusion criteria. The mean age of participants was 65.4 years and 75 patients (80.4%) were men. Over the follow-up period, 26/93 patients developed a neurodegenerative disorder. A total of 14 patients developed PD, 7 developed Lewy body dementia, 4 developed dementia that met clinical criteria for AD, and 1 developed multiple system atrophy. The estimated 5-year risk of neurodegenerative disease was 17.7%, the 10-year risk was 40.6%, and the 12-year risk was 52.4%.
Although we have found a slightly lower risk than other reports, the risk of developing neurodegenerative disease in idiopathic REM sleep behavior disorder is substantial, with the majority of patients developing Parkinson disease and Lewy body dementia.
= Diagnostic and Statistical Manual of Mental Disorders, 4th edition;
= Lewy body dementia;
= Mini-Mental State Examination;
= multiple system atrophy;
= Parkinson disease;
= REM sleep behavior disorder;
= Unified Parkinson's Disease Rating Scale.
The prevalence of sleep related complaints is reported by questionnaire studies to be as high as 83.3% in children with autism spectrum disorders (ASD). Questionnaire studies report the presence of various parasomnia in ASD. However, no polysomnographic study reports non-REM parasomnias and only a single study reports REM related parasomnias in ASD. We investigated the prevalence and characteristics of sleep disorders by polysomnographic study and questionnaires in a cohort of 23 children with ASD and 23 age-matched children of a non-autistic comparison group. The results showed significantly more non-REM parasomnias in 14 children with ASD on polysomnograms (PSG) and 16 ASD children by questionnaire, a finding that was not associated with medication use, other comorbid medical or psychiatric disorders, or sleep disordered breathing. Of the 14 children with ASD who had PSG evidence of parasomnia, 11 of them had a history suggestive of parasomnia by questionnaire. There was a high sensitivity but a low specificity of parasomnia in ASD by questionnaire in predicting the presence of parasomnia in the PSG. Of the parasomnias recorded in the laboratory, 13 ASD children had Disorders of Partial Arousal, consistent with sleep terrors or confusional arousals. Furthermore, multiple episodes of partial arousal occurred in 11 of the 13 ASD children who had PSG evidence of Disorders of Partial Arousal. Of the 11 ASD children with multiple episodes of partial arousal, 6 ASD children had multiple partial arousals during both nights’ PSG study. Sleep architecture was abnormal in children with ASD, characterized by increased spontaneous arousals, prolonged REM latency and reduced REM percentage. These results suggest a high prevalence of parasomnia in this cohort of children with ASD and a careful history intake of symptoms compatible with parasomnia could be prudent to diagnose parasomnia in ASD children when performing a PSG is not possible.
Autism spectrum disorders; parasomnia; sleep terror; confusional arousal; disorders of partial arousal
The absence of atonia during rapid eye movement (REM) sleep and dream-enactment behavior (REM sleep behavior disorder [RBD]) are common features of sleep in the alpha-synucleinopathies. This study examined this phenomenon quantitatively, using the phasic electromyographic metric (PEM), in relation to clinical features of idiopathic Parkinson disease (PD). Based on previous studies suggesting that RBD may be prognostic for the development of later parkinsonism, we hypothesized that clinical indicators of disease severity and more rapid progression would be related to PEM.
A cross-sectional convenience sample of 55 idiopathic PD patients from a movement disorders clinic in a tertiary care medical center underwent overnight polysomnography. PEM, the percentage of 2.5-second intervals containing phasic muscle activity, was quantified separately for REM and non-REM (NREM) sleep from 5 different electrode sites.
Higher PEM rates were seen in patients with symmetric disease, as well as in akinetic-rigid versus tremor-predominant patients. Men had higher PEM relative to women. Results occurred in all muscle groups in both REM and NREM sleep.
Although our data were cross-sectional, phasic muscle activity during sleep suggests disinhibition of descending motor projections in PD broadly reflective of more advanced and/or progressive disease. Elevated PEM during sleep may represent a functional window into brainstem modulation of spinal cord activity and is broadly consistent with the early pathologic involvement of non-nigral brainstem regions in PD, as described by Braak.
Parasomnias are abnormal behaviors emanating from or associated with sleep. Sleepwalking and related disorders result from an incomplete dissociation of wakefulness from nonrapid eye movement (NREM) sleep. Conditions that provoke repeated cortical arousals, or promote sleep inertia lead to NREM parasomnias by impairing normal arousal mechanisms. Changes in the cyclic alternating pattern, a biomarker of arousal instability in NREM sleep, are noted in sleepwalking disorders. Sleep-related eating disorder (SRED) is characterized by a disruption of the nocturnal fast with episodes of feeding after an arousal from sleep. SRED is often associated with the use of sedative-hypnotic medications; in particular, the widely prescribed benzodiazepine receptor agonists. Recently, compelling evidence suggests that nocturnal eating may in some cases be a nonmotor manifestation of Restless Legs Syndrome (RLS). rapid eye movement (REM) Sleep Behavior Disorder (RBD) is characterized by a loss of REM paralysis leading to potentially injurious dream enactment. The loss of atonia in RBD often predates the development of Parkinson’s disease and other disorders of synuclein pathology. Parasomnia behaviors are related to an activation (in NREM parasomnias) or a disinhibition (in RBD) of central pattern generators (CPGs). Initial management should focus on decreasing the potential for sleep-related injury followed by treating comorbid sleep disorders. Clonazepam and melatonin appear to be effective therapies in RBD, whereas paroxetine has been reported effective in some cases of sleep terrors. At this point, pharmacotherapy for other parasomnias is less certain, and further investigations are necessary.
Electronic supplementary material
The online version of this article (doi:10.1007/s13311-012-0143-8) contains supplementary material, which is available to authorized users.
Parasomnia; Sleepwalking; Sleep terrors; REM sleep behavior disorder; Restless legs syndrome
Ten patients with primary autonomic failure, followed up in a
prospective clinical and laboratory study, were finally diagnosed as
pure autonomic failure or multiple system atrophy with autonomic failure. Polysomnographic studies were performed in all patients. Whereas all four patients with multiple system atrophy complained of
sleep related episodes suggesting REM sleep behaviour disorder (RBD)
confirmed by polysomnography, RBD remained absent in the remaining six
patients with pure autonomic failure. The data indicate that RBD is an
important clinical feature, often heralding multiple system atrophy,
but which is absent throughout the course of pure autonomic failure;
its recognition can thus be useful in the prognostic evaluation of
early primary autonomic failure syndromes.
Blink reflexes (BR) to electric stimuli of the supraorbital nerve were recorded in 26 patients with dementia with Lewy bodies (DLB), 26 patients with multiple system atrophy, 26 patients with Parkinson's disease, with or without REM sleep behaviour disorder (RBD), and in 20 patients with Alzheimer's disease and 20 with progressive supranuclear palsy without RBD, and compared with recordings in 30 healthy controls. BR were significantly delayed (p<0.001) only in DLB patients in comparison with controls and with the other groups of patients; 14 (53.8%) patients had BR latency above 2 SD of the control mean, ranging from 36.1 to 46.3 ms. BR latency was not related to the presence of RBD, while a Spearman correlation rho of 0.68 was found for scores assessing the presence of cognitive fluctuations. R2 delay was prominently (71.5%) bilateral.
Decreased 123I-meta-iodobenzylguanidine (MIBG) uptake in MIBG myocardial scintigraphy, olfactory dysfunction, and rapid eye movement (REM) sleep behavior disorder (RBD) are considered useful early indicators of Parkinson disease. We investigated whether patients with PARK2 mutations exhibited myocardial sympathetic abnormalities using MIBG scintigraphy, olfactory dysfunction using the Sniffin' Sticks olfactory test, and RBD using polysomnography. None of the examined patients had RBD, and all except 1 patient exhibited an increase in the olfactory threshold. Moreover, one of the oldest patients exhibited impairment in identification and discrimination. Of 12 patients with PARK2 mutations, 4 patients, who were older than patients without abnormal uptake, exhibited decreased MIBG uptake. The results obtained in this study suggest that some patients with PARK2 mutations have increased thresholds of olfactory function and myocardial sympathetic dysfunction as nonmotor symptoms.
Parkinson's disease (PD) has traditionally been characterized by its cardinal motor symptoms of bradykinesia, rigidity, resting tremor, and postural instability. However, PD is increasingly being recognized as a multidimensional disease associated with myriad nonmotor symptoms including autonomic dysfunction, mood disorders, cognitive impairment, pain, gastrointestinal disturbance, impaired olfaction, psychosis, and sleep disorders. Sleep disturbances, which include sleep fragmentation, daytime somnolence, sleep-disordered breathing, restless legs syndrome (RLS), nightmares, and rapid eye movement (REM) sleep behavior disorder (RBD), are estimated to occur in 60% to 98% of patients with PD. For years nonmotor symptoms received little attention from clinicians and researchers, but now these symptoms are known to be significant predictors of morbidity in determining quality of life, costs of disease, and rates of institutionalization. A discussion of the clinical aspects, pathophysiology, evaluation techniques, and treatment options for the sleep disorders that are encountered with PD is presented.
Sleep disturbance is a common characteristic of patients with post-traumatic stress disorder (PTSD). Besides the clinical descriptions of nightmares and insomnia, periodic limb movements (PLMs) are reported to co-occur in PTSD. Although the causal relationship between sleep disturbance and PTSD is not fully understood, sleep disturbance is an independent risk factor for the development and reactivation of PTSD. In contrast, the link between PTSD and REM sleep behaviour disorder (RBD) is less clear.
A case report is presented to illustrate differential diagnosis and time course of sleep disturbance in the context of PTSD.
A 63-year-old man who had been successfully treated for PTSD but who suffered the re-occurrence of disturbed sleep due to RBD and PLM, which was misdiagnosed as reactivation of PTSD.
RBD can mimic PTSD-related nightmares. Accurate diagnosis of sleep disturbance in PTSD is relevant for treatment and prognostic evaluation.
posttraumatic stress disorder; REM sleep behaviour disorder; nightmares; periodic limb movements; sleep disturbance