title: An exploration of cognitive subgroups in Alzheimer's disease.
abstract: Heterogeneity is observed in the patterns of cognition in Alzheimer's disease (AD). Such heterogeneity might suggest the involvement of different etiological pathways or different host responses to pathology. A total of 627 subjects with mild/moderate AD underwent cognitive assessment with the Mini-Mental State Examination (MMSE) and the Dementia Rating Scale-2 (DRS-2). Latent class analysis (LCA) was performed on cognition subscale data to identify and characterize cognitive subgroups. Clinical, demographic, and genetic factors were explored for association with class membership. LCA suggested the existence of four subgroups; one group with mild and another with severe global impairment across the cognitive domains, one group with primary impairments in attention and construction, and another group with primary deficits in memory and orientation. Education, disease duration, age, Apolipoprotein E-epsilon4 (APOE epsilon4) status, gender, presence of grasp reflex, white matter changes, and early or prominent visuospatial impairment were all associated with class membership. Our results support the existence of heterogeneity in patterns of cognitive impairment in AD. Our observation of classes characterized by predominant deficits in attention/construction and memory respectively deserves further exploration as does the association between membership in the attention/construction class and APOE epsilon4 negative status.
authors: Memory Clinic-Neuropsychology Center, University Hospital Basel, Basel, Switzerland. julie.e.davidson@gsk.com
authors: Julie E
authors: JE
authors: Davidson
authors: Michael C
authors: MC
authors: Irizarry
authors: Bethany C
authors: BC
authors: Bray
authors: Sally
authors: S
authors: Wetten
authors: Nicholas
authors: N
authors: Galwey
authors: Rachel
authors: R
authors: Gibson
authors: Michael
authors: M
authors: Borrie
authors: Richard
authors: R
authors: Delisle
authors: Howard H
authors: HH
authors: Feldman
authors: Ging-Yuek
authors: GY
authors: Hsiung
authors: Luis
authors: L
authors: Fornazzari
authors: Serge
authors: S
authors: Gauthier
authors: Danilo
authors: D
authors: Guzman
authors: Inge
authors: I
authors: Loy-English
authors: Ron
authors: R
authors: Keren
authors: Andrew
authors: A
authors: Kertesz
authors: Peter St
authors: PS
authors: George-Hyslop
authors: John
authors: J
authors: Wherrett
authors: Andreas U
authors: AU
authors: Monsch
mesh_terms: D000368:Aged; D000544:Alzheimer Disease / Q000453:epidemiology* / Q000378:metabolism / Q000473:pathology; D053327:Apolipoprotein E4 / Q000378:metabolism; D001921:Brain / Q000378:metabolism / Q000473:pathology; D003072:Cognition Disorders / Q000145:classification* / Q000175:diagnosis / Q000453:epidemiology*; D005260:Female; D018737:Hand Strength / Q000502:physiology; D006801:Humans; D008297:Male; D009483:Neuropsychological Tests; D012720:Severity of Illness Index
chemical_list: D053327:Apolipoprotein E4