title: Cognitive decline in dementia with Lewy bodies: a 5-year prospective cohort study.
abstract: OBJECTIVE
  We report the cognitive decline in persons diagnosed with mild dementia with Lewy bodies (DLB) and mild Alzheimer's disease (AD) during 5 years of annual follow-ups.
  
  
  METHODS
  Patients were recruited into the study from geriatric, psychiatric and neurology clinics in Western Norway during 2005-2013. They were diagnosed according to clinical consensus criteria, based on standardised clinical rating scales. Autopsy-based diagnoses were available for 20 cases. Cognitive decline for up to 5 years was assessed using the Clinical Dementia Rating (CDR) scale and the Mini-Mental State Examination (MMSE). Survival analysis including Cox regression (time to reach severe dementia) and linear mixed-effects (lme) modelling were used to model the decline on MMSE.
  
  
  RESULTS
  At least one follow-up assessment was available for 67 patients with DLB and 107 patients with AD, with a median follow-up time of 4.3 years. The time to reach severe dementia was significantly shorter in DLB (median 1793 days) compared with AD (1947 days; p=0.033), and the difference remained significant in the multiple Cox regression analysis (HR=2.0, p<0.02). In the adjusted lme model, MMSE decline was faster in DLB (annual decline 4.4 points) compared with AD (3.2 points; p<0.008).
  
  
  CONCLUSIONS
  Our findings show that from the mild dementia stage, patients with DLB have a more rapid cognitive decline than in AD. Such prognostic information is vital for patients and families and crucial for planning clinical trials and enabling health economic modelling.
authors.affiliation: Department of Research and Innovation, Helse Fonna, Haugesund Hospital, Haugesund, Norway Institute of Clinical Medicine, The University of Bergen, Bergen, Norway.
authors.forename: A
authors.initials: A
authors.lastname: Rongve
authors.affiliation: Centre for Age Related Medicine, Stavanger University Hospital, Stavanger, Norway.
authors.forename: H
authors.initials: H
authors.lastname: Soennesyn
authors.affiliation: Department of Geriatric Medicine, Haraldsplass Deaconess Hospital, Bergen, Norway.
authors.forename: Ragnhild
authors.initials: R
authors.lastname: Skogseth
authors.affiliation: Centre for Age Related Medicine, Stavanger University Hospital, Stavanger, Norway.
authors.forename: Ragnhild
authors.initials: R
authors.lastname: Oesterhus
authors.affiliation: Faculty of Medicine, Department of Neuropathology, Institute of Pathology, University of Debrecen, Debrecen, Hungary King's College, London, UK.
authors.forename: T
authors.initials: T
authors.lastname: Hortobágyi
authors.affiliation: King's College, London, UK.
authors.forename: Clive
authors.initials: C
authors.lastname: Ballard
authors.affiliation: Department of Mathematics and Natural Sciences, Research Department, Stavanger University Hospital and, The University of Stavanger, Stavanger, Norway.
authors.forename: B H
authors.initials: BH
authors.lastname: Auestad
authors.affiliation: Centre for Age Related Medicine, Stavanger University Hospital, Stavanger, Norway Karolinska Institute, Stockholm, Sweden.
authors.forename: D
authors.initials: D
authors.lastname: Aarsland
mesh_terms: D000368:Aged; D003072:Cognition Disorders / Q000453:epidemiology*; D015331:Cohort Studies; D015897:Comorbidity; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D020961:Lewy Body Disease / Q000453:epidemiology*; D008297:Male; D009483:Neuropsychological Tests; D009664:Norway / Q000453:epidemiology; D011446:Prospective Studies; D011569:Psychiatric Status Rating Scales
keywords: GERIATRIC MEDICINE