title: Single-domain amnestic mild cognitive impairment identified by cluster analysis predicts Alzheimer's disease in the european prospective DESCRIPA study.
abstract: OBJECTIVE
  To identify prodromal Alzheimer's disease (AD) subjects using a data-driven approach to determine cognitive profiles in mild cognitive impairment (MCI).
  
  
  METHODS
  A total of 881 MCI subjects were recruited from 20 memory clinics and followed for up to 5 years. Outcome measures included cognitive variables, conversion to AD, and biomarkers (e.g. CSF, and MRI markers). Two hierarchical cluster analyses (HCA) were performed to identify clusters of subjects with distinct cognitive profiles. The first HCA included all subjects with complete cognitive data, whereas the second one selected subjects with very mild MCI (MMSE ≥28). ANOVAs and ANCOVAs were computed to examine whether the clusters differed with regard to conversion to AD, and to AD-specific biomarkers.
  
  
  RESULTS
  The HCAs identified 4-cluster solutions that best reflected the sample structure. One cluster (aMCIsingle) had a significantly higher conversion rate (19%), compared to subjective cognitive impairment (SCI, p < 0.0001), and non-amnestic MCI (naMCI, p = 0.012). This cluster was the only one showing a significantly different biomarker profile (Aβ42, t-tau, APOE ε4, and medial temporal atrophy), compared to SCI or naMCI.
  
  
  CONCLUSIONS
  In subjects with mild MCI, the single-domain amnestic MCI profile was associated with the highest risk of conversion, even if memory impairment did not necessarily cross specific cut-off points. A cognitive profile characterized by isolated memory deficits may be sufficient to warrant applying prevention strategies in MCI, whether or not memory performance lies below specific z-scores. This is supported by our preliminary biomarker analyses. However, further analyses with bigger samples are needed to corroborate these findings.
authors: Department of Geriatric Psychiatry, Clinic of Psychiatry and Psychotherapy, Central Institute of Mental Health, Medical Faculty Mannheim/Heidelberg University, Mannheim, Germany. marinella.damian@zi-mannheim.de
authors: Marinella
authors: M
authors: Damian
authors: Lucrezia
authors: L
authors: Hausner
authors: Katrin
authors: K
authors: Jekel
authors: Melany
authors: M
authors: Richter
authors: Lutz
authors: L
authors: Froelich
authors: Ove
authors: O
authors: Almkvist
authors: Merce
authors: M
authors: Boada
authors: Roger
authors: R
authors: Bullock
authors: Peter Paul
authors: PP
authors: De Deyn
authors: Giovanni B
authors: GB
authors: Frisoni
authors: Harald
authors: H
authors: Hampel
authors: Roy W
authors: RW
authors: Jones
authors: Patrick
authors: P
authors: Kehoe
authors: Hermine
authors: H
authors: Lenoir
authors: Lennart
authors: L
authors: Minthon
authors: Marcel G M
authors: MG
authors: Olde Rikkert
authors: Guido
authors: G
authors: Rodriguez
authors: Philip
authors: P
authors: Scheltens
authors: Hilkka
authors: H
authors: Soininen
authors: Luiza
authors: L
authors: Spiru
authors: Jacques
authors: J
authors: Touchon
authors: Magda
authors: M
authors: Tsolaki
authors: Bruno
authors: B
authors: Vellas
authors: Frans R J
authors: FR
authors: Verhey
authors: Bengt
authors: B
authors: Winblad
authors: Lars-Olof
authors: LO
authors: Wahlund
authors: Gordon
authors: G
authors: Wilcock
authors: Pieter Jelle
authors: PJ
authors: Visser
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000150:complications / Q000453:epidemiology* / Q000523:psychology; D001057:Apolipoproteins E / Q000235:genetics; D015415:Biomarkers; D016000:Cluster Analysis; D060825:Cognitive Dysfunction / Q000150:complications / Q000453:epidemiology* / Q000523:psychology; D015331:Cohort Studies; D018450:Disease Progression; D005060:Europe / Q000453:epidemiology; D005260:Female; D005838:Genotype; D006801:Humans; D016015:Logistic Models; D008279:Magnetic Resonance Imaging; D008297:Male; D011939:Mental Recall / Q000502:physiology; D008875:Middle Aged; D009483:Neuropsychological Tests; D015203:Reproducibility of Results; D014057:Tomography, X-Ray Computed
chemical_list: D001057:Apolipoproteins E; D015415:Biomarkers