Isolated REM Sleep Behaviour Disorder-Is Screening Possible?

Abstract

Rapid eye movement (REM) sleep behaviour disorder (RBD) is a parasomnia characterised by the loss of muscle atonia during REM sleep and dream-enacting behaviours. In its isolated form (iRBD) it is widely recognised as an early stage of alpha-synucleinopathies. Early identification of patients with iRBD allows for timely interventions, risk mitigation and potential inclusion in clinical trials aimed at disease modification. Effective screening tools, including questionnaires, automatic analyses of video-polysomnography, actigraphy, nearables and biological markers, can facilitate diagnosis and monitoring. Incorporating routine screening into clinical practice may enhance early detection and improve long-term patient outcomes. This manuscript presents the latest developments in screening tools for the identification of patients with iRBD and discusses their advantages and drawbacks, highlighting paths for future research and applications.

Keywords: RBD; iRBD; prodromal alpha‐synucleinopathy; screening tool.

FIGURE 1

Typical example of 30 s of REM sleep in a patient with iRBD. It is possible to appreciate the presence of RWA in the EMG channels (mentalis, submentalis, bilateral FDS and bilateral tibialis anterior). EMG, electromyography; FDS, flexor digitorum superficialis; iRBD, isolated REM sleep behaviour disorder; REM, rapid eye movement; RWA, REM sleep without atonia.

FIGURE 2

Overview of the screening methods for patients with iRBD described in this manuscript. Please note that the figure does not report biological markers (Section 6) and other markers (Section 7), because those markers might not be specific for iRBD, as they aim at detecting neurodegeneration independently from the presence of RBD.