title: Comparison of neuropsychological profiles in patients with Alzheimer's disease and mixed dementia.
abstract: OBJECTIVE
  We designed this study to extensively compare the neuropsychological profiles of Alzheimer's disease (AD) and mixed dementia (MD) in a large multicenter cohort of patients. Specifically, we performed subgroup analyses to examine group differences associated with dementia severity.
  
  
  METHODS
  A total of 1021 AD patients and 577 MD patients were included from the Clinical Research Center for Dementia of South Korea (CREDOS) Study. All patients underwent comprehensive neuropsychological and functional ratings, as well as complete physical and neurological examinations. To avoid floor confounds, only patients with Clinical Dementia Rating (CDR) scores of 0.5-2.0 were included.
  
  
  RESULTS
  Overall, MD patients showed worse performance in frontal/executive function than those with AD. Stratification by dementia severity revealed a significant difference in global cognitive function scores between AD and MD patients only in the low severity groups (CDR 0.5). Also, MD patients showed worse performance in frontal/executive function domains in the CDR 0.5 groups whereas they had better performance in the memory domain in the CDR 1 groups than did AD patients. Additionally, AD patients showed better performance than MD patients with respect to activities of daily living at CDR levels 0.5 and 1. All differences had disappeared at the CDR 2 level of global dementia severity.
  
  
  CONCLUSIONS
  This study suggests that there are significant differences in neuropsychological profiles between AD and MD patients, with the pattern of this difference varying distinctively according to dementia severity.
authors.affiliation: Center for Clinical Research, Samsung Biomedical Research Institute, Seoul, Republic of Korea; Department of Clinical and Counseling Psychology, Korea University, Seoul, Republic of Korea.
authors.forename: Hyo Shin
authors.initials: HS
authors.lastname: Kang
authors.affiliation: Department of Clinical and Counseling Psychology, Korea University, Seoul, Republic of Korea.
authors.forename: Jung Hye
authors.initials: JH
authors.lastname: Kwon
authors.affiliation: Department of Psychiatry, The Catholic University of Korea College of Medicine, Seoul, Republic of Korea.
authors.forename: Sangha
authors.initials: S
authors.lastname: Kim
authors.affiliation: Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.
authors.forename: Duk L
authors.initials: DL
authors.lastname: Na
authors.affiliation: Department of Psychiatry, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea.
authors.forename: Seong Yoon
authors.initials: SY
authors.lastname: Kim
authors.affiliation: Department of Neurology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea.
authors.forename: Jae-Hong
authors.initials: JH
authors.lastname: Lee
authors.affiliation: Department of Neurology, Konkuk University School of Medicine, Seoul, Republic of Korea.
authors.forename: Seol-Heui
authors.initials: SH
authors.lastname: Han
authors.affiliation: Department of Neurology, Inha University School of Medicine, Incheon, Republic of Korea.
authors.forename: Seong Hye
authors.initials: SH
authors.lastname: Choi
authors.affiliation: Department of Neurology, Seoul National University College of Medicine, Seoul, Republic of Korea.
authors.forename: SangYun
authors.initials: S
authors.lastname: Kim
authors.affiliation: Pacific Behavioral Research Foundation, Carmel, CA, USA.
authors.forename: Bernard J
authors.initials: BJ
authors.lastname: Carroll
authors.affiliation: Center for Clinical Research, Samsung Biomedical Research Institute, Seoul, Republic of Korea; Department of Psychiatry, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea. Electronic address: paulkim@skku.edu.
authors.forename: Doh Kwan
authors.initials: DK
authors.lastname: Kim
mesh_terms: D000203:Activities of Daily Living / Q000523:psychology; D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000150:complications* / Q000523:psychology; D003072:Cognition Disorders / Q000175:diagnosis* / Q000209:etiology*; D003704:Dementia / Q000150:complications* / Q000523:psychology; D056344:Executive Function / Q000502:physiology; D005260:Female; D006801:Humans; D008297:Male; D009483:Neuropsychological Tests; D011569:Psychiatric Status Rating Scales; D018709:Statistics, Nonparametric
keywords: Alzheimer's disease; Dementia severity; Mixed dementia; Neuropsychological profiles