title: Longitudinal changes in medial temporal cortical thickness in normal subjects with the APOE-4 polymorphism.
abstract: People with the apolipoprotein-Eepsilon4 (APOE-4) genetic risk for Alzheimer's disease show morphologic differences in medial temporal lobe regions when compared to non-carriers of the allele. Using a high-resolution MRI and cortical unfolding approach, our aim was to determine the rate of cortical thinning among medial temporal lobe subregions over the course of 2 years. We hypothesized that APOE-4 genetic risk would contribute to longitudinal cortical thickness change in the subiculum and entorhinal cortex, regions preferentially susceptible to Alzheimer's disease related pathology. Thirty-two cognitively intact subjects, mean age 61 years, 16 APOE-4 carriers, 16 non-carriers, underwent baseline and follow-up MRI scans. Over this relatively brief interval, we found significantly greater cortical thinning in the subiculum and entorhinal cortex of APOE-4 carriers when compared to non-carriers of the allele. Average cortical thinning across all medial temporal lobe subregions combined was also significantly greater for APOE-4 carriers. This finding is consistent with the hypothesis that carrying the APOE-4 allele renders subjects at a higher risk for developing Alzheimer's disease.
authors.affiliation: David Geffen School of Medicine at UCLA, Center for Cognitive Neurosciences, Semel Institute, Los Angeles, CA 90095, USA.
authors.forename: Markus
authors.initials: M
authors.lastname: Donix
authors.forename: Alison C
authors.initials: AC
authors.lastname: Burggren
authors.forename: Nanthia A
authors.initials: NA
authors.lastname: Suthana
authors.forename: Prabha
authors.initials: P
authors.lastname: Siddarth
authors.forename: Arne D
authors.initials: AD
authors.lastname: Ekstrom
authors.forename: Allison K
authors.initials: AK
authors.lastname: Krupa
authors.forename: Michael
authors.initials: M
authors.lastname: Jones
authors.forename: Anup
authors.initials: A
authors.lastname: Rao
authors.forename: Laurel
authors.initials: L
authors.lastname: Martin-Harris
authors.forename: Linda M
authors.initials: LM
authors.lastname: Ercoli
authors.forename: Karen J
authors.initials: KJ
authors.lastname: Miller
authors.forename: Gary W
authors.initials: GW
authors.lastname: Small
authors.forename: Susan Y
authors.initials: SY
authors.lastname: Bookheimer
mesh_terms: D000544:Alzheimer Disease / Q000235:genetics* / Q000473:pathology*; D053327:Apolipoprotein E4 / Q000235:genetics*; D002540:Cerebral Cortex / Q000473:pathology*; D005260:Female; D020022:Genetic Predisposition to Disease / Q000235:genetics; D006579:Heterozygote; D006801:Humans; D008137:Longitudinal Studies; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D008875:Middle Aged; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D012016:Reference Values
chemical_list: D053327:Apolipoprotein E4