Characterising the prodromal phase of dementia with Lewy bodies

Abstract

AbstractBackgroundThree subtypes of prodromal dementia with Lewy bodies (DLB) have recently been proposed. This study investigates the frequency of symptoms in the prodromal phase of DLB.MethodPatients diagnosed with DLB between the 1st of February 2017 and 1st of February 2021 were retrospectively identified and matched to a group of patients with Alzheimer’s disease (AD). Patient case files were reviewed identifying the first symptoms and symptoms in the prodromal phase (cognitive impairment, psychiatric symptoms, delirium/acute confusional episodes, RBD, motorsymptoms indicative of Parkinson’s disease, anosmia, and autonomic dysfunction).ResultsA retrospective cohort of 166 DLB patient and 168 AD patients were included. Of the proposed subtypes in patients diagnosed with DLB, 30% presented with cognitive impairment at onset in isolation, 6% with psychiatric symptoms, and 2% with delirium/acute confusional episodes (Figure). Eighty‐three percent of DLB patients had two or more non‐cognitive symptoms in the prodromal phase. Further, 82 % had at least one psychiatric symptom, and 33 % had an episode with delirium/acute confusional episode in the prodromal phase. Of other possible subtypes, Rapid eye movement sleep Behaviour Disorder was found at onset in 22% with a mean prodromal length of 8.4 years (as opposed to 4.3 years in DLB generally)ConclusionWe found no supportive evidence of the proposed clinical subtypes of prodromal DLB. Our findings indicate that RBD subtypes may exist, but further research is needed.