title: Cerebrovascular risk factors and brain microstructural abnormalities on diffusion tensor images in HIV-infected individuals.
abstract: HIV-associated neurocognitive disorder remains prevalent in HIV-infected individuals despite effective antiretroviral therapy. As these individuals age, comorbid cerebrovascular disease will likely impact cognitive function. Effective tools to study this impact are needed. This study used diffusion tensor imaging (DTI) to characterize brain microstructural changes in HIV-infected individuals with and without cerebrovascular risk factors. Diffusion-weighted MRIs were obtained in 22 HIV-infected subjects aged 50 years or older (mean age = 58 years, standard deviation = 6 years; 19 males, three females). Tensors were calculated to obtain fractional anisotropy (FA) and mean diffusivity (MD) maps. Statistical comparisons accounting for multiple comparisons were made between groups with and without cerebrovascular risk factors. Abnormal glucose metabolism (i.e., impaired fasting glucose, impaired glucose tolerance, or diabetes mellitus) was associated with significantly higher MD (false discovery rate (FDR) critical p value = 0.008) and lower FA (FDR critical p value = 0.002) in the caudate and lower FA in the hippocampus (FDR critical p value = 0.004). Pearson correlations were performed between DTI measures in the caudate and hippocampus and age- and education-adjusted composite scores of global cognitive function, memory, and psychomotor speed. There were no detectable correlations between the neuroimaging measures and measures of cognition. In summary, we demonstrate that brain microstructural abnormalities are associated with abnormal glucose metabolism in the caudate and hippocampus of HIV-infected individuals. Deep gray matter structures and the hippocampus may be vulnerable in subjects with comorbid abnormal glucose metabolism, but our results should be confirmed in further studies.
authors.affiliation: University of Hawaii, Honolulu, HI, USA. beau_nakamoto@yahoo.com
authors.forename: Beau K
authors.initials: BK
authors.lastname: Nakamoto
authors.forename: Neda
authors.initials: N
authors.lastname: Jahanshad
authors.forename: Aaron
authors.initials: A
authors.lastname: McMurtray
authors.forename: Kalpana J
authors.initials: KJ
authors.lastname: Kallianpur
authors.forename: Dominic C
authors.initials: DC
authors.lastname: Chow
authors.forename: Victor G
authors.initials: VG
authors.lastname: Valcour
authors.forename: Robert H
authors.initials: RH
authors.lastname: Paul
authors.forename: Liron
authors.initials: L
authors.lastname: Marotz
authors.forename: Paul M
authors.initials: PM
authors.lastname: Thompson
authors.forename: Cecilia M
authors.initials: CM
authors.lastname: Shikuma
mesh_terms: D000375:Aging; D019380:Anti-HIV Agents / Q000008:administration & dosage / Q000627:therapeutic use; D001786:Blood Glucose / Q000032:analysis; D002421:Caudate Nucleus / Q000098:blood supply / Q000473:pathology*; D002561:Cerebrovascular Disorders / Q000150:complications / Q000188:drug therapy / Q000473:pathology*; D003072:Cognition Disorders / Q000150:complications / Q000188:drug therapy / Q000473:pathology*; D003920:Diabetes Mellitus / Q000188:drug therapy / Q000473:pathology*; D056324:Diffusion Tensor Imaging; D004522:Educational Status; D005260:Female; D015658:HIV Infections / Q000150:complications / Q000188:drug therapy / Q000473:pathology*; D006624:Hippocampus / Q000098:blood supply / Q000473:pathology*; D006801:Humans; D008297:Male; D008568:Memory; D008875:Middle Aged; D011597:Psychomotor Performance; D012307:Risk Factors
chemical_list: D019380:Anti-HIV Agents; D001786:Blood Glucose