Movement Disorders in Sleep

Hydromorphone-induced chorea as an atypical presentation of opioid neurotoxicity: A case report and review of the literature

“…14,15 While it was previously accepted that hyperkinetic movement disorders cease during sleep, persistence of chorea during sleep in a subset of patients has since been well documented. 16,17 The majority of nocturnal choreic movements have been observed during non-rapid eye movement (NREM) sleep and following arousals although patients with Sydenham’s chorea have been shown to have chorea persist into rapid eye movement (REM) sleep. 18,19 It has also been hypothesized that in certain patients the regulation of motor function at the level of the basal ganglia may vary during the sleep–wake cycle, thereby resulting in nocturnal chorea.…”