Subtle gray matter changes involving medial temporo-parietal cortex associated to cardiovascular risk factors: A possible link to Alzheimer's disease

Abstract

Battery (Ganguly et al 1996), Everyday Abilities Scale for India (Fillenbaum et al 1999) was administered on subjects.Ten ml of venous blood was collected, genomic DNA extracted, and genotyping done at apolipoprotein-E locus according to standard procedure. The DTI images were obtained on the Philips 3T Archieva MRI scanner. Fractional Anisotropy (FA) maps were extracted using FSL-FDT software package. Voxel based morphometric (VBM) analysis was performed on the FA maps using study specific custom template by applying two sample t-test, at significance level of p 1⁄4 0.001 with threshold masking of 0.2 on white matter segmented FA maps using Statistical Parametric Mapping (SPM) 5 version. Results: Between patients with AD and controls the areas of significant difference was noticed in bilateral temporal lobes, bilateral limbic lobe, Left insula, uncus, amygdala & parahippocampal regions and Right posterior cingulate region. Bilateral temporal lobe and right subgyral parietal lobe area was differing between APOE e4 carrier and non-carrier AD patients. Conclusions: Patients with AD have abnormalities in white matter tracts in regions of temporal lobe compared to controls. Apo E4 carrier status is associated with structural changes in white matter integrity in patients with AD. Findings indicate the need for further study using VBM approach in white matter tracts of patients with AD and apoE4 allele.