Voxel Based Morphometry Findings in an Irish Cohort of HIV Positive Patients (S10.004)

Objective The objective of this study was to assess for focal atrophy in patients with HIV associated neurocognitive disorder and to examine for hippocampal atrophy in those who demonstrated amnestic features on neuropsychological testing. Background HIV associated neurocognitive disorder (HAND) occurs in up to 50% of patients with HIV despite effective antiretroviral therapy. Global cerebral atrophy is common in HAND. Recent studies have also demonstrated focal atrophy in the anterior cingulate and temporal cortices. Design/Methods This was a cross-sectional study to assess focal atrophy in patients with cognitive impairment secondary to HIV. Participants included 50 HIV positive patients, 41 men and 9 women, and 50 age and gender matched healthy volunteers. The 50 HIV positive patients had a positive screen for cognitive impairment and also underwent neuropsychological testing. T1-weighted magnetic resonance imaging 3D datasets using a SENSE protocol (3 Tesla Philips scanner; flip angle=8°, field of view= 256mm, 160 slices, voxel size 1×1 x 1mm3) were performed for all subjects. 40/50 of the HIV positive patients met diagnostic criteria for HAND; 28/50 asymptomatic neurocognitive impairment, 11/50 mild neurocognitive disorder, 1/50 HIV associated dementia. The remaining 10 patients had cognitive impairment in one domain only. Voxel based morphometry analysis was carried out using the FMRIB Software Library (FSL). The predominant neuropsychological profile was a dysexecutive amnestic pattern. Results Statistically significant differences were found in the anterior cingulate bilaterally (p=0.0042), left hippocampus (p=0.04), inferior parietal lobe bilaterally (p=0.0228), bilateral insular cortex (p=0.0138), right medial temporal lobe (p=0.0134), left entorhinal cortex (p=0.0254) and bilateral occipital cortex (p=0.03). Discussion These findings support the dysexecutive amnestic findings of the neuropsychological tests with involvement of the anterior cingulate, temporal cortices and hippocampus. Disclosure: Dr. McNamara has received research support from AbbVie. Dr. Redmond has nothing to disclose. Dr. Bede has received research support from the Elan Fellowship in Neurodegeneration. Dr. Fagan has nothing to disclose. Dr. Bergin has received personal compensation for activities with AbbVie, Janssen Pharmaceutica, Merck Sharp & Dohme Limited, Gilead, and Bristol-Myers Squibb Company. Dr. Bergin has received research support from the Health Research Board of Ireland. Dr. Bokde has nothing to disclose. Dr. Doherty has received personal compensation for activities with UCB Pharma, Eisai Inc., and Janssen-Cilag.