Sleep Abnormalities in MultipleSystem Atrophy

Patient-perceived progression in multiple system atrophy: natural history of quality of life

BACKGROUND

Health-related quality of life (Hr-QoL) scales provide crucial information on neurodegenerative disease progression, help improve patient care and constitute a meaningful endpoint for therapeutic research. However, Hr-QoL progression is usually poorly documented, as for multiple system atrophy (MSA), a rare and rapidly progressing alpha-synucleinopathy. This work aimed to describe Hr-QoL progression during the natural course of MSA, explore disparities between patients and identify informative items using a four-step statistical strategy.

METHODS

We leveraged the data of the French MSA cohort comprising annual assessments with the MSA-QoL questionnaire for more than 500 patients over up to 11 years. A four-step strategy (1) determined the subdimensions of Hr-QoL, (2) modelled the subdimension trajectories over time, (3) mapped item impairments with disease stages and (4) identified most informative items.

RESULTS

Four dimensions were identified. In addition to the original motor, non-motor and emotional domains, an oropharyngeal component was highlighted. While the motor and oropharyngeal domains deteriorated rapidly, the non-motor and emotional aspects were already impaired at cohort entry and deteriorated slowly over the disease course. Impairments were associated with sex, diagnosis subtype and delay since symptom onset. Except for the emotional domain, each dimension was driven by key identified items.

CONCLUSION

The multidimensional Hr-QoL deteriorates progressively over the course of MSA and brings essential knowledge for improving patient care. As exemplified with MSA, the thorough description of Hr-QoL over time using the four-step strategy can provide perspectives on neurodegenerative diseases' management to ultimately deliver better support focused on the patient's perspective.

Associations of sleep-related variables with reverse dipping patterns of blood pressure in α-synucleinopathies

INTRODUCTION

The reverse dipping blood pressure (BP) pattern is very common in α-synucleinopathies. We aimed to explore the associations of sleep-related variables with abnormal BP circadian rhythms in Parkinson's disease (PD) and multiple system atrophy (MSA).

METHODS

A total of 126 patients, 76 with PD and 50 with MSA, were included. All participants underwent ambulatory BP monitoring and full-night polysomnography (PSG). We analyzed abnormal dipping patterns and sleep-related parameters, including moderate to severe obstructive sleep apnea (OSA), rapid eye movement behavior disorder (RBD), average oxygen saturation (SaO2%), lowest SaO2%, duration of SaO2% <90%, and apnea-hypopnea index (AHI). Binary logistic regression was performed to explore the associations between paraclinical variables, sleep-related variables, and reverse dipping patterns.

RESULTS

Reverse dipping patterns were predominant in patients with PD (58.5 %) and MSA (68.0 %). Patients with MSA had higher AHI, RBD, and lower average SaO2% than those with PD. Taking both diseases together as a whole group of α-synucleinopathies, logistic regression analysis indicates the Hoehn-Yahr stage (odds ratio [OR] = 2.00 for reverse systolic and 2.34 for reverse diastolic dipping patterns), moderate to severe OSA (OR = 2.71 for reverse systolic and 2.53 for reverse diastolic dipping patterns), average SaO2% (OR = 1.35 for reverse systolic dipping patterns), and male sex (OR = 2.70 for reverse diastolic dipping patterns) were independently associated with reverse dipping patterns.

CONCLUSIONS

Reverse dipping patterns were common in patients with PD and MSA. Hoehn-Yahr stage, moderate to severe OSA, average SaO2%, and male sex were associated with reverse dipping patterns in α-synucleinopathy.

Longitudinal evolution of sleep disturbances in early multiple system atrophy: a 2-year prospective cohort study

BACKGROUND

The progression of sleep disturbances remains unclear in patients with early multiple system atrophy (MSA). We aimed to explore the frequency, severity, and coexistence of 2-year longitudinal changes of sleep disturbances including REM sleep behavior disorder (RBD), excessive daytime sleepiness (EDS), and Parkinson's disease-related sleep problems (PD-SP) in early MSA.

METHODS

MSA patients with a disease duration < 3 years were enrolled to complete a 2-year follow-up visit. Sleep disturbances including RBD, EDS, and PD-SP were assessed using the RBD Screening Questionnaire, Epworth sleepiness scale, and PD sleep scale-2, respectively.

RESULTS

A total of 220 patients with MSA enrolled in the study and 90 patients completed the 2-year follow-up visit. The score of all three sleep disturbances significantly increased over the 2-year follow-up in MSA and MSA with the predominant parkinsonism group (all p < 0.05). The frequency of PD-SP (from 14.5 to 26.7%) and EDS (from 17.7 to 37.8%) was progressively increased (all p < 0.05) except for RBD (from 51.8 to 65.6%, p = 0.152) over the 2-year follow-up in MSA. The frequency of coexistence of two or three sleep disturbances also increased over time. The most common sleep disturbance was RBD, followed by EDS and PD-SP over the 2-year follow-up.

CONCLUSIONS

The present study demonstrated that the frequency of different types of sleep disturbances progressively increased except for RBD and the coexistence of two or three sleep disturbances became more common over time in early MSA. Our study suggested that the assessment and management of sleep disturbances should begin early in MSA.

Neurologic Disorders in Women and Sleep

Sleep disorders in women remain underrecognized and underdiagnosed mainly because of gender bias in researching and characterizing sleep disorders in women. Symptoms of common sleep disorders are frequently missed in the general female population and are expected to be further overlooked because of overlapping symptoms in women with neurologic disorders. Given the bidirectional relationship with sleep and neurologic disorders, it remains critical to be aware of the presentation and impact of sleep disorders in this patient population. This article reviews available data on sleep disorders in women with neurologic disorders and discusses their distinctive features.

Continuous Positive Airway Pressure for the Treatment of Supine Hypertension and Orthostatic Hypotension in Autonomic Failure

BACKGROUND

Supine hypertension affects most patients with orthostatic hypotension (OH) due to autonomic failure, but it is often untreated for fear of worsening OH. We hypothesized that increasing intrathoracic pressure with continuous positive airway pressure (CPAP) had a Valsalva-like blood-pressure-lowering effect that could be used to treat nocturnal supine hypertension in these patients, while reducing nocturnal pressure diuresis and improving daytime OH.

METHODS

In Protocol 1, we determined the acute hemodynamic effects of increasing levels of CPAP (0, 4, 8, 12, and 16 cm H2O, 3 minutes each) in 26 patients with autonomic failure and supine hypertension studied while awake and supine. In Protocol 2 (n=11), we compared the effects of overnight therapy with CPAP (8-12 cm H2O for 8 hours) versus placebo on nocturnal supine hypertension, nocturnal diuresis and daytime OH in a 2-night crossover study.

RESULTS

In Protocol 1, acute CPAP (4-16 cm H2O) decreased systolic blood pressure in a dose-dependent manner (maximal drop 22±4 mmHg with CPAP 16) due to reductions in stroke volume (-16+3%) and cardiac output (-14±3%). Systemic vascular resistance and heart rate remained unchanged. In Protocol 2, overnight CPAP lowered nighttime systolic blood pressure (maximal change -23±5 versus placebo -1±7 mmHg; P=0.023) and was associated with lower nighttime diuresis (609±84 versus placebo 1004±160 mL; P=0.004) and improved morning orthostatic tolerance (AUC upright SBP 642±121 versus placebo 410±109 mmHg*min; P=0.014).

CONCLUSIONS

CPAP is a novel nonpharmacologic approach to treat the supine hypertension of autonomic failure while improving nocturia and daytime OH.

REGISTRATION

URL: https://www.

CLINICALTRIALS

gov; Unique identifier: NCT03312556.

Circadian disruption and sleep disorders in neurodegeneration

Disruptions of circadian rhythms and sleep cycles are common among neurodegenerative diseases and can occur at multiple levels. Accumulating evidence reveals a bidirectional relationship between disruptions of circadian rhythms and sleep cycles and neurodegenerative diseases. Circadian disruption and sleep disorders aggravate neurodegeneration and neurodegenerative diseases can in turn disrupt circadian rhythms and sleep. Importantly, circadian disruption and various sleep disorders can increase the risk of neurodegenerative diseases. Thus, harnessing the circadian biology findings from preclinical and translational research in neurodegenerative diseases is of importance for reducing risk of neurodegeneration and improving symptoms and quality of life of individuals with neurodegenerative disorders via approaches that normalize circadian in the context of precision medicine. In this review, we discuss the implications of circadian disruption and sleep disorders in neurodegenerative diseases by summarizing evidence from both human and animal studies, focusing on the bidirectional links of sleep and circadian rhythms with prevalent forms of neurodegeneration. These findings provide valuable insights into the pathogenesis of neurodegenerative diseases and suggest a promising role of circadian-based interventions.

Central sleep apnea and daytime sleepiness in Niemann-Pick type C disease: a report of 2 cases

Niemann-Pick disease type C (NPC) is an autosomal recessive hereditary disease in which sphingomyelin and cholesterol are deposited in various organs of the body. The clinical manifestations of NPC include neurologic symptoms and cataplexy; other symptoms related to sleep have seldom been reported. One previous study described various sleep disorders including chronic insomnia, obstructive sleep apnea, restless legs syndrome, and rapid eye movement sleep behavior disorder, thus suggesting that sleep disorders in patients with NPC are more prevalent than previously thought and warrant close attention. Here, we describe sleep disorders in 2 patients with NPC and discuss the clinical characteristics and, for the first time, discuss potential pathogenic mechanisms underlying sleep disorders in such patients.

CITATION

Zhang Y, Cheng Y, Li N, et al. Central sleep apnea and daytime sleepiness in Niemann-Pick type C disease: a report of 2 cases. J Clin Sleep Med. 2023;19(2):409-414.

What Is the Prognostic Significance of Rapid Eye Movement Sleep Without Atonia in a Polysomnogram?

SUMMARY

Freud said we are lucky to be paralyzed during sleep, so we cannot act out our dreams. Atonia of skeletal muscles normally present during rapid eye movement sleep prevents us from acting out our dreams. Observing rapid eye movement sleep without atonia in a polysomnogram in older adults first and foremost warrants consideration of rapid eye movement behavior disorder. Seventy-five to 90% of older adults with isolated rapid eye movement behavior disorder will develop a neurodegenerative disease within 15 years, most often a synucleinopathy. Rapid eye movement sleep without atonia in those younger than 50 years is commonly found in individuals with narcolepsy and those taking antidepressant medications.

Sighs during sleep in multiple system atrophy

Sighs are physiological phenomena and may occasionally occur during sleep in healthy young adults. Although inspiratory sighs are considered a diagnostic red flag for the parkinsonian form of multiple system atrophy (MSA), its frequency and characteristics are unclear. We aimed to define sigh frequency during sleep recordings in patients with MSA compared to Parkinson's disease (PD) patients, as well as evaluate possible associated breathing disorders or autonomic changes. We analyzed 9 polysomnography's from patients with MSA and 9 from matched PD patients. The proportion of MSA patients (both MSA-P and MSA-C) with sleep-related sighs was significantly higher than that of PD patients, and these occurred predominantly in stages N1 and N2. The median sigh index in sleep and wakefulness were also significantly higher in MSA, although with a significant inter-subject variability. Higher sigh indexes were not associated to other breathing disturbances or with longer disease duration. In MSA, 12% of sighs were associated with oxygen desaturation, while none of the events in PD patients presented with significant changes in oxygen saturation. Respiratory events followed 45% of sighs in MSA, predominantly central sleep apneas, and 29% of sighs in PD, predominantly hypopneas. Our data suggests that high sigh frequencies during sleep should also be considered a red flag for MSA, and future studies should aim to determine whether increased sighing frequency during sleep is specific for this disorder.

Sleep disorders in autoimmune encephalitis

Sleep disorders in people with autoimmune encephalitis have received little attention, probably overshadowed by the presence of other neurological and psychiatric symptoms in this group of conditions. However, sleep disorders are frequent, often severe, and usually persist beyond the acute disease stage, interfering with patients' recovery and quality of life. Because autoimmune encephalitis can affect any brain network involved in sleep initiation and regulation, all types of sleep disorders can occur, with varying distinct associations, frequency, and intensity. Anti-IgLON5 and anti-NMDA receptor encephalitis exemplify two diseases in which sleep disorders are prominent. In anti-IgLON5 disease, sleep disorders were the core symptoms that led to the description of this disease, whereas in anti-NMDA receptor encephalitis, sleep disorders vary according to the disease stage along with other neuropsychiatric symptoms. Comprehensive, systematic, multicentre studies are needed to characterise sleep disorders and their mechanisms in autoimmune encephalitis.

Current Management and Emerging Therapies in Multiple System Atrophy

Multiple system atrophy (MSA) is a progressive neurodegenerative disease variably associated with motor, nonmotor, and autonomic symptoms, resulting from putaminal and cerebellar degeneration and associated with glial cytoplasmic inclusions enriched with α-synuclein in oligodendrocytes and neurons. Although symptomatic treatment of MSA can provide significant improvements in quality of life, the benefit is often partial, limited by adverse effects, and fails to treat the underlying cause. Consistent with the multisystem nature of the disease and evidence that motor symptoms, autonomic failure, and depression drive patient assessments of quality of life, treatment is best achieved through a coordinated multidisciplinary approach driven by the patient's priorities and goals of care. Research into disease-modifying therapies is ongoing with a particular focus on synuclein-targeted therapies among others. This review focuses on both current management and emerging therapies for this devastating disease.

MicroRNA: A Key Player for the Interplay of Circadian Rhythm Abnormalities, Sleep Disorders and Neurodegenerative Diseases

Circadian rhythms are endogenous 24-h oscillators that regulate the sleep/wake cycles and the timing of biological systems to optimize physiology and behavior for the environmental day/night cycles. The systems are basically generated by transcription-translation feedback loops combined with post-transcriptional and post-translational modification. Recently, evidence is emerging that additional non-coding RNA-based mechanisms are also required to maintain proper clock function. MicroRNA is an especially important factor that plays critical roles in regulating circadian rhythm as well as many other physiological functions. Circadian misalignment not only disturbs the sleep/wake cycle and rhythmic physiological activity but also contributes to the development of various diseases, such as sleep disorders and neurodegenerative diseases. The patient with neurodegenerative diseases often experiences profound disruptions in their circadian rhythms and/or sleep/wake cycles. In addition, a growing body of recent evidence implicates sleep disorders as an early symptom of neurodegenerative diseases, and also suggests that abnormalities in the circadian system lead to the onset and expression of neurodegenerative diseases. The genetic mutations which cause the pathogenesis of familial neurodegenerative diseases have been well studied; however, with the exception of Huntington's disease, the majority of neurodegenerative diseases are sporadic. Interestingly, the dysfunction of microRNA is increasingly recognized as a cause of sporadic neurodegenerative diseases through the deregulated genes related to the pathogenesis of neurodegenerative disease, some of which are the causative genes of familial neurodegenerative diseases. Here we review the interplay of circadian rhythm disruption, sleep disorders and neurodegenerative disease, and its relation to microRNA, a key regulator of cellular processes.