Oral Presentation Australian and New Zealand Society for Geriatric Medicine Annual Scientific Meeting 2025

The prodromal presentation of dementia with Lewy bodies: experience from an Australian cohort study (119712)

Paula M Loveland 1 2 , Kai Sin Chin 1 2 , Jenny J Yu 1 2 , Nawaf Yassi 1 2 3 , Rosie Watson 1 2
  1. Genetics and Gene Regulation division, The Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia
  2. Department of Medicine, The Royal Melbourne Hospital, University of Melbourne, Parkville, VIC, Australia
  3. Department of Neurology, Melbourne Brain Centre at The Royal Melbourne Hospital, University of Melbourne, Parkville, VIC, Australia

Aim: To classify the prodromal stage of dementia with Lewy bodies (DLB) in an Australian cohort against the recently proposed research criteria1, and to describe the frequency of DLB clinical features in the prodrome. This addresses current challenges in recognising prodromal DLB, which contributes to delayed diagnosis and limits prospective research into early disease.

Methods: Participants with DLB were enrolled in an Australian cohort study. Retrospective file review by 3 independent assessors, followed by expert consensus discussion, classified participants against the research criteria (mild cognitive impairment with Lewy bodies (MCI-LB), delirium-onset or psychiatric-onset presentations) and identified the frequency of clinical features during the prodrome (cognitive, gait/motor, autonomic, sleep, psychiatric, loss of smell or taste).

Results: Of 45 participants (mean age 73.6+/-5.6 years, 84% male), 80% were MCI-onset, 11% delirium-onset, 7% psychiatric-onset and only one (2%) was unclear. Cognitive fluctuation was the commonest (80%) core DLB clinical feature in the prodrome, followed by REM-sleep behaviour disorder (69%), motor parkinsonism (47%) and visual hallucinations (11%). All participants had cognitive features during the prodrome.  Sleep (80%), psychiatric (73%) and gait/motor (67%) symptoms were also common.

Conclusion: MCI-LB was the most common prodrome of DLB, although selection bias against psychiatric-onset and delirium-onset presentations is likely in research cohorts that recruit from memory clinics. Detection of prominent DLB-associated symptoms could alert clinicians to proactively monitor for emerging DLB. Research recruitment should consider ways to identify non-cognitive DLB prodromes, including sleep and psychiatric disturbance, which were prevalent in our cohort.

  1. 1. McKeith IG, Ferman TJ, Thomas AJ, Blanc F, Boeve BF, Fujishiro H, et al. Research criteria for the diagnosis of prodromal dementia with Lewy bodies. Neurology. 2020;94(17):743-55.