title: A two-year follow-up of cognitive deficits and brain perfusion in mild cognitive impairment and mild Alzheimer's disease.
abstract: The 15-Objects Test (15-OT) provides useful gradation of visuoperceptual impairment from normal aging through Alzheimer's disease (AD) and correlates with temporo-parietal perfusion. The objectives of this study were to analyze progression of 15-OT performance in mild cognitive impairment (MCI) and AD, and its correlates with cognition and single photon emission computerized tomography (SPECT), as well as to examine neuropsychological and SPECT differences between the MCI patients who developed AD and those who did not. From the initial 126 participants (42/group), 38 AD, 39 MCI, and 38 elderly controls (EC) were reassessed (SPECT: 35 AD, 33 MCI, 35 EC) after two years. The progression of cognitive and SPECT scores during this period was compared between groups, and baseline data between converters and non-converters. The 15-OT was the only measure of progression that differed between the three groups; worsening scores on 15-OT were associated with worsening in verbal and visual retention, and decreased perfusion on left postsubicular area. In the MCI patients, cerebral perfusion fell over the two years in medial-posterior cingulate and fronto-temporo-parietal regions; AD showed extensive changes involving almost all cerebral regions. No SPECT changes were detected in controls. At baseline, the MCI patients who developed AD differed from non-converters in verbal recognition memory, but not in SPECT perfusion. In conclusion, SPECT and 15-OT appear to provide a potential measure to differentiate between normal aging, MCI, and AD. Worsening on 15-OT was related to decreased perfusion in postsubicular area; but further longitudinal studies are needed to determine the contribution of 15-OT as a predictor of AD from MCI.
authors.affiliation: Memory Clinic of Fundació ACE, Institut Català de Neurociències Aplicades, C/Marquès de Sentmenat 35-37, Barcelona, Spain. malegret@fundacioace.com
authors.forename: Montserrat
authors.initials: M
authors.lastname: Alegret
authors.forename: Gemma
authors.initials: G
authors.lastname: Cuberas-Borrós
authors.forename: Georgina
authors.initials: G
authors.lastname: Vinyes-Junqué
authors.forename: Ana
authors.initials: A
authors.lastname: Espinosa
authors.forename: Sergi
authors.initials: S
authors.lastname: Valero
authors.forename: Isabel
authors.initials: I
authors.lastname: Hernández
authors.forename: Isabel
authors.initials: I
authors.lastname: Roca
authors.forename: Agustín
authors.initials: A
authors.lastname: Ruíz
authors.forename: Maitée
authors.initials: M
authors.lastname: Rosende-Roca
authors.forename: Ana
authors.initials: A
authors.lastname: Mauleón
authors.forename: James T
authors.initials: JT
authors.lastname: Becker
authors.forename: Joan
authors.initials: J
authors.lastname: Castell-Conesa
authors.forename: Lluís
authors.initials: L
authors.lastname: Tárraga
authors.forename: Mercè
authors.initials: M
authors.lastname: Boada
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000000981:diagnostic imaging / Q000473:pathology*; D001921:Brain / Q000000981:diagnostic imaging* / Q000473:pathology; D002560:Cerebrovascular Circulation / Q000502:physiology*; D060825:Cognitive Dysfunction / Q000000981:diagnostic imaging / Q000473:pathology*; D018450:Disease Progression; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D009483:Neuropsychological Tests; D011569:Psychiatric Status Rating Scales; D018709:Statistics, Nonparametric; D013997:Time Factors; D015899:Tomography, Emission-Computed, Single-Photon