Adequacy of Using Consensus Guidelines for Diagnosis of Dementia with Lewy Bodies in Clinical Trials for Drug Development

Background/Aims: To evaluate the adequacy of using the consensus diagnostic criteria for dementia with Lewy bodies (DLB) to recruit patients with homogeneous characteristics in future clinical trials, where multiple departments of multinational centres are expected to participate with a long enrolment period, and additionally, to contribute to the possible future criteria revision. Methods: Using data from 2 trials of donepezil for DLB, conducted 3 years apart, characteristics in patients with probable DLB were analysed and compared between studies and between psychiatric and neurological centres. Results: In 273 patients (phase II: 135, phase III: 138; psychiatric: 73, neurological: 184), clinical characteristics overall were very similar between studies, and between specialty centres, excluding distinctive parkinsonism in the neurological versus psychiatric centres: incidence of parkinsonism (91.8 vs. 71.2%, p < 0.001), Hoehn and Yahr stage (III: 55.0 vs. 21.2%, p < 0.001), and concomitant anti-Parkinson medication (24.5 vs. 11.0%, p = 0.017). Rapid eye movement sleep behaviour disorder, depression, and delusion, suggestive or supportive features, were observed in 35-40%. Additionally, a high prevalence (55.3%) of anxiety was observed. Conclusion: Employing the consensus criteria is adequate to enrol homogeneous DLB patients into future clinical trials regardless of the specialty of centres and time. Further discussion could involve adding anxiety to future criteria.