Takashi Nomura

To explore the clinical significance of restless legs syndrome (RLS) in Parkinson's disease (PD) and the causal relationship between these two disorders, we made a comparison of both the prevalence of RLS and the severity of sleep disturbance manifested on the Pittsburg Sleep Quality Index (PSQI) between patients with PD (n = 165) and age‐ and sex‐matched control subjects (n = 131). The prevalence of RLS diagnosed by clinical interview was significantly higher in PD patients than in control subjects (12% vs. 2.3%). PSQI score was significantly higher in PD patients with RLS than in both patients without RLS and controls. However, PSQI score was not statistically different between the latter two groups. Among the PD patients with RLS, only 2 had a positive family history of RLS. Only 3 PD patients had requested treatment for the disorder. Our results emphasize the etiological link between RLS and PD in a Japanese cohort, and the existence of RLS is thought to be one of the most important factors aggravating sleep disturbance in PD, despite the low RLS severity. © 2005 Movement Disorder Society

To clarify whether visual hallucinations in patients with Parkinson's disease (PD) are related to rapid eye movement (REM) sleep, nocturnal polysomnographic variables were compared between a group with hallucinations (hallucinators, n = 14) and a group without hallucinations (nonhallucinators, n = 8). A multiple sleep latency test (MSLT) was performed on 3 hallucinators, and the content of dreams during daytime REM sleep was investigated. The efficacy of clonazepam, a standard treatment choice for REM sleep behavior disorders, was investigated in 8 hallucinators. Nocturnal polysomnograms of the hallucinators showed a higher amount of stage 1–REM sleep with tonic electromyogram (stage 1–REM) than the nonhallucinators, and the reported occurrences of nocturnal hallucinations corresponded with the periods of stage REM or stage 1–REM in most hallucinators. The frequency of sleep onset REM periods (SOREMP) on the MSLT were pathologically high in the hallucinators, and the content of the dreams during the MSLT period was quite similar to their hallucinations. During clonazepam treatment, the frequency of hallucinatory symptoms decreased in 5 of 8 hallucinators. These results indicate that visual hallucinations in PD are likely to be related to a REM sleep disorder manifested as the appearance of both stage 1–REM during the night and SOREMP in the daytime. © 2003 Movement Disorder Society