Aim of the study was to compare prevalence of sleep disturbances in patients with Parkinson's disease (PD) and in subjects with ischaemic stroke of the right cerebral hemispher and to estimate an effect of daytime sleepiness on sustained attention in patients with PD.
Material and methods: Forty eight patients with PD were included. The mean age was 65.9 (44-80) years, mean disease duration and mean Hoehn and Yahr Staging Scale were 6.6 (0.8-18) years and 2.5 (1.0-4.0), respectively. Control group consists of forty seven patients (mean age 66.2 years) with ischaemic stroke of the right cerebral hemisphere, without any language problems (mean Rankin Scale: 2.0). Both, PD and control patients were evaluated with: Parkinson's Disease Sleep Scale (PDSS), Epworth Sleepiness Scale (ESS) and Beck Depression Inventory (BDI). PD patients were also assessed with Visual Continuous Attention Test (DAUF).
Results: PD patients obtained significantly lower (p < 0.05) scores on PDSS and significantly higher (p < 0.01) scores on ESS than patients with stroke. There were no significant differences within PD and control subjects on BDI. On the basis of ESS results PD patients were divided into two subgroups: PD1--patients with daytime sleepiness (ESS score > 10.0) and PD2--patients without daytime sleepiness. PD1 patients obtained significantly worse scores than PD2 ones on DAUF (significantly decreased number of correct reactions: p < 0.05 and significantly increased number of incorrect reactions: p < 0.05).
Conclusions: Nighttime sleep disturbances and daytime sleepiness are more pronounced in PD patients than in subjects with ischaemic stroke of the right cerebral hemisphere. PD subjects with daytime sleepiness show disturbances in the sustained attention.