Automated morphological analysis techniques (MRI, diffusion tensor imaging and neurocognitive assessments) have shown the association of apolipoprotein E (ApoE4) allele in the brain of healthy, non-demented older adults with decrease in cognition, according to a study published in this month’s Journal of Alzheimer's Disease.
Lead investigator Robyn A. Honea, PhD, research assistant professor in the department of neurology at the University of Kansas Medical Center, Kansas City, Kan., said: “We assessed differences in cognition and brain structure associated with ApoE4 genetic variation using voxel-based morphometry techniques, tract-based spatial statistics of fractional anisotropy change.”
In the study, MRI, diffusion tensor imaging and neurocognitive assessments were performed on gray and white matter in the brains of 53 non-demented subjects over 60 years in age.
The investigators found that in healthy, nondemented older adults with the ApoE4 allele, cognitive performance was reduced, and atrophy was present in the hippocampus and amygdala compared with ApoE4 negative participants.
Honea and colleagues also noted that E4 carriers have decreased fractional anisotropy in the left parahippocampal gyrus white matter.
"It is important to note that findings of imaging phenotypes of risk variants, such as with this gene, have been shown in a number of studies," Honea said. "The unique element of our study is that we used several new neuroimaging analysis techniques. In addition, the individuals in our study have been well-characterized in a clinical setting."