Secondary RBD: Not just neurodegeneration.

Rapid eye movement sleep behavior disorder is a parasomnia characterized by excessive muscle activity during rapid eye movement sleep (rapid eye movement sleep without atonia), along with dream enactment behavior. Isolated rapid eye movement sleep behavior disorder tends to occur in older males and is of concern due to the known link to Parkinson's disease and other synucleinopathies. When rapid eye movement sleep behavior disorder occurs in association with other neurological or general medical conditions, or resulting from the use of various substances, it is called secondary rapid eye movement sleep behavior disorder; the most common cause is neurodegenerative illness, specifically the synucleinopathies. Here, the focus will be on the subset of secondary rapid eye movement sleep behavior disorder in which there is no neurodegenerative disease.

Trauma-Associated Sleep Disorder.

Trauma-associated sleep disorder (TASD) is a recently described parasomnia that develops following a traumatic event. It consists of trauma-related nightmares, disruptive nocturnal behaviors, and autonomic disturbances, and shares similarities with post-traumatic stress disorder and rapid eye movement behavior disorder. The underlying pathophysiology of TASD and how it relates to other parasomnias are still not entirely understood; proposed treatment is similarly nebulous, with prazosin at the forefront along with management of comorbid sleep disorders. The purpose of this article is to characterize and highlight the clinical features of this condition.

Headache improves with armodafinil.

This case report recounts the details of a patient diagnosed with narcolepsy and cataplexy whose headaches improved once treatment with armodafinil began. The clinical significance of this report lies in the fact that armodafinil is known to cause headaches, at least initially. But perhaps through a reduced need for caffeine and/or a regulation of sleep/wake, armodafinil may reduce headache frequency and severity. CITATION: Barone DA. Headache improves with armodafinil. J Clin Sleep Med. 2024;20(3):469-470.

Neurologic and psychiatric features of impending neurodegeneration in iRBD.

Introduction: Idiopathic rapid eye movement (REM) sleep behavior disorder (iRBD) is linked to Parkinson's disease and other alpha-synucleinopathies, but various subsets of iRBD may not carry equal risk (i.e., those with depression are at higher risk than those without). Here, we prospectively focus on neurologic and psychiatric aspects of subjects with iRBD, in an attempt to determine what factors are prominent in those who undergo phenoconversion as opposed to those who do not. Methods: We analyzed data from the "REM Sleep Behavior Disorder Associations with Parkinson's Disease Study (RAPiDS)" cohort both at baseline and then at follow-up evaluations (1 to 3 years later) utilizing several neurologic batteries, including the Movement Disorder Society's Unified Parkinson's Disease Rating Scale (MDS-UPDRS), the Montreal Cognitive Assessment (MoCA), the Questionnaire for Impulsive-Compulsive Disorders in Parkinson's Disease (QUIP), the 10-M Walk Test (10MWT), and the Epworth Sleepiness Scale. Determination of phenoconversion was ascertained from physical examination and medical chart review from the initial evaluation onward. Results: Of those who completed both evaluations, there were 33 subjects with iRBD, with an average age of 63.1 ± 12.8 years, with 9 women and 24 men. Of these, 8 (24%) iRBD subjects developed neurodegenerative illness, and demonstrated multiple areas of neurologic and psychiatric signs and symptoms, such as speech and movement problems as well as anxiety and depression. Conclusions: Our data adds to the literature regarding risk of phenoconversion in those with iRBD. Further study will be needed, but it is clear that not all subjects with iRBD present the same risk for neurodegeneration.

Obstructive Sleep Apnea and Positive Airway Pressure Usage in Populations with Neurological Disease.

Obstructive sleep apnea (OSA) is characterized by repetitive episodes of complete or partial upper airway obstruction during sleep, with a worldwide estimate of 936 million sufferers. Treatments of OSA include continuous positive airway pressure (CPAP), weight loss, positional therapy, oral appliances, positive upper airway pressure, oro-maxillofacial surgery, hypoglossal nerve stimulation, and bariatric surgery, and others, with CPAP being the most commonly prescribed treatment. In this review, the neurologic conditions of stroke, cognitive decline, epilepsy, and migraines will be discussed as they relate to OSA. Additionally, the literature regarding improvement in these conditions following treatment with CPAP will be explored.

Dream enactment behavior-a real nightmare: a review of post-traumatic stress disorder, REM sleep behavior disorder, and trauma-associated sleep disorder.

NONE: Dream enactment behavior is a phenomenon demonstrated in patients with post-traumatic stress disorder, rapid eye movement sleep behavior disorder, as well as with a more recently described condition entitled trauma-associated sleep disorder, which shares diagnostic criteria for rapid eye movement sleep behavior disorder. While these conditions share some commonalities, namely dream enactment behavior, they are quite different in pathophysiology and underlying mechanisms. This review will focus on these 3 conditions, with the purpose of increasing awareness for trauma-associated sleep disorder in particular.

Comorbid neuropsychiatric and autonomic features in REM sleep behavior disorder.

OBJECTIVE: Our aim is to define the extent of comorbidities in order to improve clinical care of patients with idiopathic rapid eye movement sleep behavior disorder (iRBD) utilizing the REM Sleep Behavior Disorder Associations with Parkinson's Disease Study (RAPiDS) cohort. METHODS: Consecutive adult study participants with iRBD confirmed on polysomnogram (PSG) were prospectively recruited from the Weill Cornell Center for Sleep Medicine. Evaluations comprised multiple facets of sleep, neurological, autonomic, and psychiatric function. RESULTS: Participants evaluated included 30 individuals with iRBD, with mean 1.5 ±â€¯2.3 years from PSG to neuropsychiatric evaluation. Mean age was 59.5 ±â€¯16.0 years at time of PSG, and 6/30 were women. Urinary difficulties were reported in 14/30 (47%): slight 7 (23%), mild 4 (13%), moderate 2 (7%), and severe 1 (3.0%). Ten out of 29 (34%) had abnormal Montreal Cognitive Assessment (MoCA) scores and the mean was 26.5 ±â€¯3.2. The distribution of MoCA scores was significantly associated with urinary problems insofar as the more severe urinary problems were, the lower the MoCA scores (p = 0.04). CONCLUSIONS: In this RAPiDS cohort, we detected an unexpectedly high occurrence of non-motor dysfunction. Our results point to the need for screening patients with iRBD for complaints that are actionable, for example those affecting mood, cognition, urinary function, and bowel function. We propose the term RBD+ to be used to identify such individuals. For the quality of life in patients diagnosed with RBD, a closer look by the clinician should be enacted, with appropriate referrals and workup.

Rapid eye movement sleep behavior disorder and the link to alpha-synucleinopathies.

Rapid eye movement (REM) sleep behavior disorder (RBD) involves REM sleep without atonia in conjunction with a recurrent nocturnal dream enactment behavior, with vocalizations such as shouting and screaming, and motor behaviors such as punching and kicking. Secondary RBD is well described in association with neurological disorders including Parkinson's disease (PD), multiple system atrophy (MSA), and other conditions involving brainstem structures such as tumors. However, RBD alone is now considered to be a potential harbinger of later development of neurodegenerative disorders, in particular PD, MSA, dementia with Lewy bodies (DLB), and pure autonomic failure. These conditions are linked by their underpinning pathology of alpha-synuclein protein aggregation. In RBD, it is therefore important to recognize the potential risk for later development of an alpha-synucleinopathy, and to investigate for other potential causes such as medications. Other signs and symptoms have been described in RBD, such as orthostatic hypotension, or depression. While it is important to recognize these features to improve patient management, they may ultimately provide clinical clues that will lead to risk stratification for phenoconversion. A critical need is to improve our ability to counsel patients, particularly with regard to prognosis. The ability to identify who, of those with RBD, is at high risk for later neurodegenerative disorders will be paramount, and would in addition advance our understanding of the prodromal stages of the alpha-synucleinopathies. Moreover, recognition of at-risk individuals for neurodegenerative disorders may ultimately provide a platform for the testing of possible neuroprotective agents for these neurodegenerative disorders.

Heart rate variability in restless legs syndrome and periodic limb movements of Sleep.

INTRODUCTION: The relationship between the autonomic nervous system and restless legs syndrome (RLS) and periodic limb movements of sleep (PLMS) consists of varied and somewhat conflicting reports. In order to further elucidate these complexities, a retrospective analysis of polysomnography (PSG) records and clinical data was performed. METHODS: Records from 233 adult subjects were randomly selected and organized into one of four groups ("non-RLS/PLMS" [n=61], "RLS" [n=60], "PLMS" [n=58], and "RLS/PLMS" [n=54]). Heart rate variability (HRV) analysis was based on 5-minute samples of 2-lead electrocardiogram data isolated from PSG recordings during wakefulness and NREM sleep, and included mean RR interval (labeled "NN") and standard deviation of the RR intervals (labeled "SDNN"), and HRV power, very low frequency (VLF), low frequency (LF), and high frequency (HF) spectral bands. RESULTS: A significant reduction in the VLF band in the PLMS group as compared to the non-RLS/PLMS group (542±674 vs. 969±1025 ms2, p=0.038) was found in wakefulness. Statistically significant differences were seen in the PLMS group as compared to the non-RLS/PLMS group with a reduction in SDNN (p=0.001) and the HF (p=0.001) band, and an increase in HRV power (p=0.001), and the VLF (p=0.005) and LF (p=0.001) bands in NREM sleep. CONCLUSIONS: The PLMS group exhibited reduced basal sympathetic activity in wakefulness, but basal sympathetic predominance during NREM sleep, distinguishing this group from the RLS and RLS/PLMS groups.

Neurologic Diseases and Sleep.

Sleep disorders and neurologic illness are common and burdensome in their own right; when combined, they can have tremendous negative impact at an individual level as well as societally. The socioeconomic burden of sleep disorders and neurologic illness can be identified, but the real cost of these conditions lies far beyond the financial realm. There is an urgent need for comprehensive care and support systems to help with the burden of disease. Further research in improving patient outcomes in those who suffer with these conditions will help patients and their families, and society in general.

A 45-Year-Old Man With Delayed Onset of OSA Events During Polysomnography.

A 45-year-old man with a medical history that included asthma and chronic nasal congestion presented for an evaluation of possible OSA. He reported loud snoring, witnessed apneas in sleep, and daytime sleepiness. The patient's score on the Epworth Sleepiness Scale was 12 of 24, indicating excessive sleepiness. His nasal congestion had been treated with frequent use of an over-the-counter nasal decongestant.

Sleep disturbances in voltage-gated potassium channel antibody syndrome.

Voltage-gated potassium channels (VGKCs) are a family of membrane proteins responsible for controlling cell membrane potential. The presence of antibodies (Ab) against neuronal VGKC complexes aids in the diagnosis of idiopathic and paraneoplastic autoimmune neurologic disorders. The diagnosis of VGKC Ab-associated encephalopathy (VCKC Ab syndrome) should be suspected in patients with subacute onset of disorientation, confusion, and memory loss in the presence of seizures or a movement disorder. VGKC Ab syndrome may present with sleep-related symptoms, and the purpose of this communication is to alert sleep and neurology clinicians of this still-under-recognized condition. In this case, we are presenting the VGKC Ab syndrome which improved after treatment with solumedrol. The prompt recognition and treatment of this condition may prevent the morbidity associated with cerebral atrophy and the mortality associated with intractable seizures and electrolyte disturbances.

Autonomic dysfunction in isolated rapid eye movement sleep without atonia.

OBJECTIVES: Autonomic dysfunction has been demonstrated in patients with rapid eye movement sleep behavior disorder utilizing heart rate variability parameters. We hypothesized that isolated rapid eye movement sleep without atonia is similarly associated with autonomic dysfunction as demonstrated by a reduction in heart rate variability. METHODS: An evaluation of 120 records demonstrating rapid eye movement sleep without atonia during polysomnography was performed. Many (n=99) were discarded owing to factors potentially affecting heart rate variability. The remaining 21 records were matched with 21 records of patients demonstrating normal REM atonia, and subjected to electrocardiogram analysis. The parameters measured included R to R interval (RR) length, RR standard deviation, heart rate variability power, and very low frequency, low frequency, and high frequency bands. RESULTS: Autonomic dysfunction was seen in patients with isolated rapid eye movement sleep without atonia as denoted by a reduction in heart rate variability compared to those with normal REM atonia. Significant differences between the groups were demonstrated in RR standard deviation (mean difference=0.1502 ± 0.317, 95% confidence interval [95% CI]=0.006, 0.295, p=0.042), heart rate variability power (mean difference=0.3005 ± 0.635, 95% CI=0.011, 0.589, p=0.042), and the low frequency band (mean difference=0.3166 ± 0.616 ms(2), 95% CI=0.036, 0.597, p=0.029), and a borderline significant reduction in the high frequency band (mean difference=0.3121 ± 0.686 ms(2), 95% CI=0.000, 0.624, p=0.050). CONCLUSIONS: Our data confirms the hypothesis that heart rate variability is reduced in patients with isolated rapid eye movement sleep without atonia. The values obtained are consistent with previous findings in rapid eye movement behavior sleep disorder patients. SIGNIFICANCE: This is the first report of autonomic dysfunction in isolated rapid eye movement sleep without atonia, revealing the need for further evaluation of the clinical significance and potential implications of this finding.

Stroke and obstructive sleep apnea: a review.

Obstructive sleep apnea (OSA) has been found to be an independent risk factor for stroke in large epidemiological studies. The mechanisms underlying this relationship have been investigated over the past 2-3 decades, with a particular focus on identifying pathophysiological pathways and risk modification strategies. Despite the advancements made, the specific understanding of the implicated mechanisms is still limited. This brief review focuses on presenting some of the epidemiological evidence of the linkage between OSA and stroke, discussing mechanistic pathways and the potential effect of OSA treatment in modulating the risk for stroke in these patients. Future directions for research in this field are also discussed.

Alternative devices for obstructive sleep apnea.

Obstructive sleep apnea (OSA) is a relatively common condition which is most often treated with continuous positive airway pressure (CPAP). Given the compliance issues associated with CPAP, it is important for neurologists (and anyone who treats OSA) to be aware of what other treatment devices exist for this disease. This article reviews mandibular advancement devices, nasal expiratory airway pressure devices, hypoglossal nerve stimulators, and oral pressure therapy devices in terms of their mechanism of action, efficacy, and practicality.