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

Abstract

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.

Review: Clinical, neuropathological and genetic features of Lewy body dementias

“…RBD is recognised as a prodromal stage of PD and DLB . Greater density and greater range of α‐synuclein pathology was found in PD patients with probable RBD .…”

REM Behavior Disorder diagnostic challenges

“…apid eye movement (REM) sleep behavior disorder (RBD) is a relevant sleep disorder for neurologists, psychiatrists, and geriatricians since it is currently recognized as a condition that represents a prolonged prodromal state of neurodegenerative disorders, mainly alpha-synucleinopathies 1 . Despite the importance of its early detection for adequate long-term care planning and counseling, RBD remains underdiagnosed, particularly in its mild form, with mild symptoms, in which patients or their bed partners do not experience harm, injury, or significant sleep disruption 2 .…”

Parkinson gaixotasunaren biomarkatzaile klinikoen paperaren azterketa, ikuspegi epidemiologiko batetik

“…• REM loaren jokabide-alterazioak (TCSR/REMJA): TCSRa PGan orain arte gehien aztertu izan den biomarkatzailea da (1). TCSRa nahaste neurologikoekin lotuta dagoela ikusi da, horien artean PGarekin, atrofia multisistemarekin (7,9). Meta-analisi baten arabera TCSRa zutenen % 82,4k hamar urteko jarraipenean neuroendekapenezko gaixotasun bat garatu zuen.…”