Objective: This study aimed to systematically review the effects of currently prescribed antiparkinson medication on cognition in patients with mild-to-moderate Parkinson’s disease (PD) who were either cognitively intact or mildly impaired. Methods: English- and French-language studies published between 1969 and 2017 were accessed via MedLine, PsychNET, EMBASE and EBSCO databases. Methodological quality (MQ) was evaluated with the quality assessment instrument of the Cochrane Collaboration Depression, Anxiety and Neurosis Review (scores from 0% to 44% indicate very low quality; scores from 45% to 64% indicate low quality; scores from 65% to 84% indicate medium quality; and scores from 85% to 100% indicate high quality). Hedges’ g and Student’s t-test were performed on all cognitive outcome measures reported. Results: In total, 14 studies assessed the cognitive effects of levodopa (L-D), pramipexole (PRX), selegiline (SEL) and rasagiline (RAS) in mild-to-moderate non-demented PD patients. The MQ was overall low, with an average score of 49.1%. Results for L-D showed deleterious effects on a test of cognitive inhibition, as well as benefits on tests of attention/processing speed/working memory, executive functions and episodic memory. Pramipexole was associated with a worsening of episodic memory and impulse control. Results on SEL indicated a deterioration of global cognition over time and of concept formation. Rasagiline had some benefits on working memory and verbal fluency. Conclusion: Antiparkinson medications can have deleterious (L-D; PRX; SEL) and beneficial (L-D; RAS) effects on cognition. However, randomized double-blind placebo-controlled trials with larger sample sizes are required to better elucidate this issue.

Background: The prevalence of sleep disturbances among patients with Parkinson’s disease (PD) is estimated to occur in 37% to 98% of patients. Sleep disturbances have been associated with a reduced quality of life for patients with PD. The objective of this study was to assess the impact of rasagiline treatment on the severity of sleep disturbances among patients with idiopathic PD. Methods: In this open-label, multicentre study, 110 adult patients with idiopathic PD were treated with rasagiline either as monotherapy or as adjunct therapy. The primary endpoint was the change in severity of sleep disturbances, assessed with the PD Sleep Scale from baseline to month 2. Exploratory endpoints included change in daytime sleepiness, assessed with the Epworth Sleep Scale, treatment satisfaction measured with the Treatment Satisfaction Questionnaire for Medication, patient’s overall improvement or deterioration over time measured with the Clinical Global Impression of Improvement, tolerability, and safety. Findings: Patients treated with rasagiline as mono- or adjunct therapy showed a statistically significant improvement in sleep quality after 2 months. There was no change in daytime sleepiness. Overall, patients were satisfied with rasagiline treatment with a mean Treatment Satisfaction Questionnaire for Medication [standard deviation] total score at month 2 of 68% [16.1]. At the end of study, 64 patients (65.9%) were judged, by the investigator, as being at least minimally improved from baseline on the Clinical Global Impression of Improvement. Rasagiline was safe and well-tolerated. Interpretation: Rasagiline as mono- or adjunct-therapy may improve sleep experience in patients with PD in the short term.