Sleep‐related rhythmic movement disorder in adults – A systematic review with a case report

Summary Sleep‐related rhythmic movement disorder is characterised by stereotyped and repetitive rhythmic movements involving large muscle groups during sleep with frequencies between 0.5 and 2 Hz. Most of the published studies on sleep‐related rhythmic movement disorder have focussed on children. Therefore, we performed a systematic review on this topic focussing on the adult population. The review is followed by a case report. The review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta‐Analyses 2020 guidelines. A total of seven manuscripts ( n = 32 individuals) were included in the review. The clinical manifestation of body or head rolling predominated in the majority of included cases (53.13% and 43.75%, respectively). In n = 11 (34.37%) cases, a combination of rhythmic movements was observed. The literature review also revealed a wide spectrum of co‐morbidities: insomnia, restless leg syndrome, obstructive sleep apnea, ischaemic stroke, epilepsy, hypertension, alcohol and drug dependency, mild depression, and diabetes mellitus. The case report presented a 33‐year‐old female who was referred to the sleep laboratory due to a suspicion of sleep bruxism and obstructive sleep apnea. Although the patient was initially suspected of having obstructive sleep apnea and sleep bruxism, after conducting video‐polysomnography she met the criteria for sleep‐related rhythmic movement disorder as she presented body rolling, which were surprisingly most evident during the rapid eye movement sleep stage. In summary, the prevalence of sleep‐related rhythmic movement disorder among adults has not been determined yet. The present review and case report is a good starting point for discussion regarding rhythmic movement disorder in adults and further research on this topic.