Article

Longitudinal changes in medial temporal cortical thickness in normal subjects with the APOE-4 polymorphism.

David Geffen School of Medicine at UCLA, Center for Cognitive Neurosciences, Semel Institute, Los Angeles, CA 90095, USA.
NeuroImage (Impact Factor: 6.13). 10/2010; 53(1):37-43. DOI: 10.1016/j.neuroimage.2010.06.009
Source: PubMed

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.

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