Improvements in nocturnal symptoms with ropinirole prolonged release in patients with advanced Parkinson's disease

Background: The 24-week, double-blind Efficacy and Safety Evaluation in PD-Adjunct (EASE-PD Adjunct) study randomized patients with advanced Parkinson's disease (PD) suboptimally controlled with levodopa to once-daily placebo or adjunctive ropinirole prolonged release (2-24mg/day). We investigated the effect of ropinirole prolonged release on nocturnal symptoms in these patients. Methods: Total and grouped item PD Sleep Scale (PDSS) scores were analyzed post hoc in patients with baseline PDSS total scores ≤100 (troublesome nocturnal symptoms) and >100. Results: Baseline PDSS total score was ≤100 in 93 of 198 (47%) and 89 of 189 (47%) patients receiving ropinirole prolonged release and placebo, respectively; this subgroup displayed evidence at baseline of greater daily awake 'off' time, reduced night-time sleep and worse quality of life, than the PDSS>100 subgroup. Significant improvements with ropinirole prolonged release versus placebo in PDSS score from baseline to Week 24 last observation carried forward were observed for those with baseline PDSS≤100 [adjusted mean treatment difference 9.0 (95% CI: 2.76, 15.33; P=0.0051)], but not >100. The PDSS≤100 subgroup demonstrated treatment benefits for PDSS groupings of motor symptoms on waking and global quality of sleep. Changes in daytime sleepiness were similar between treatment groups. The PDSS>100 subgroup demonstrated significant treatment benefit for global quality of sleep. The unadjusted odds ratio for a positive response with ropinirole prolonged release relative to placebo, for the PDSS≤100 subgroup, was 2.90 (95% CI: 1.42, 5.95, P=0.004). Conclusions: Once-daily ropinirole prolonged release improves nocturnal symptoms in patients with advanced PD not optimally controlled with levodopa who suffer troublesome nocturnal disturbance.