Memantine improves goal attainment and reduces caregiver burden in Parkinson's disease with dementia

OBJECTIVE: Memantine, an uncompetitive antagonist of N-methyl-d-aspartate receptors, may have a role in managing symptoms associated with dementia in Parkinson's disease (PDD), although its role in improving patient-reported outcomes (PROs) has not been extensively investigated. PROs may be more sensitive than standard psychometric measures for detecting change in complex conditions such as PDD. The aim of this study was to examine the effect of memantine on PROs: individually determined goals and health-related quality of life. We also examined memantine's effect on caregiver burden. METHODS: This 22-week double-blind randomised controlled trial evaluated participants with PDD on 20?mg of memantine or placebo. Outcome measures were Goal Attainment Scaling (GAS), the Parkinson's Disease Questionnaire-8 and the Zarit Burden Inventory. RESULTS: A significantly greater proportion of participants on memantine (64%) had better than expected GAS outcomes compared with those on placebo (7%) (p?=?0.007). Furthermore, the improvement in mean GAS score, as well as mean caregiver burden score, from baseline to drug discontinuation was significantly greater in those on memantine compared with those on placebo (p?=?0.03 and 0.04, respectively). Significant differences in quality of life were not seen. CONCLUSIONS: In this study, memantine improved individually set goals and caregiver burden in PDD. This suggests that clinimetric measures such as GAS may be more sensitive than conventional psychometric measures in detecting improvements in people with PDD.