Cholinesterase inhibitors in dementia with Lewy bodies: a comparative analysis

OBJECTIVE: To compare efficacy of different cholinesterase inhibitors (ChEIs) for treating patients with dementia with Lewy bodies (DLB). DESIGN: Retrospective comparison of three independent clinical studies of ChEI treatment using donepezil, galantamine or rivastigmine in patients with DLB. METHOD: Data was obtained from open label trials of donepezil and galantamine and a placebo controlled randomized trial of rivastigmine in DLB. Changes in Mini Mental State Examination (MMSE), Neuropsychiatric Inventory (NPI) and United Parkinson's Disease Rating Scale (UPDRS-III) scores were compared between the three treatments at 12 and 20 weeks. RESULTS: All ChEIs significantly improved cognitive and neuropsychiatric measures. Reduction in the total NPI score appeared significantly greater after donepezil treatment. There was no significant increase in UPDRS-III scores. CONCLUSIONS: It is unclear to what extent these findings reflect true differences between ChEIs or are due to methodological artefacts of comparing different studies. There is so far no compelling evidence that any one ChEI is better than the other in treating DLB but head to head comparative studies of different ChEIs are warranted to clarify this.