Objectives: To study the efficacy of cholinesterase inhibitors in the treatment of dementia in patients with Parkinson's disease (PD).
Methods: We treated twenty-eight demented patients with PD openly for 26 weeks with rivastigmine (mean daily dose 7.2 +/- 3.3 mg/day). Baseline scores were compared with those at weeks 12, 26 and after 8 weeks of washout.
Results: Twenty patients completed 26 weeks of treatment and eight dropped out because of side effects. The Unified Parkinson's Disease Rating Scale mental subscore improved significantly at week 26 (P < 0.01) while the motor score (part III) did not change. The mean ADAScog total score improved by 7.3 points at week 26 (P < 0.002). The subscores for recognition, word finding, remembering instructions and concentration items of the ADAScog improved significantly as well (P < 0.02, P < 0.05, P < 0.005 and P < 0.003, respectively).
Conclusions: Rivastigmine may improve the cognitive functions in PD patients with dementia with no worsening of motor function.