Mapping white matter integrity in elderly people with HIV.
People with HIV are living longer as combination antiretroviral therapy (cART) becomes more widely available. However, even when plasma viral load is reduced to untraceable levels, chronic HIV infection is associated with neurological deficits and brain atrophy beyond that of normal aging. HIV is often marked by cortical and subcortical atrophy, but the integrity of the brain's white matter (WM) pathways also progressively declines. Few studies focus on older cohorts where normal aging may be compounded with HIV infection to influence deficit patterns. In this relatively large diffusion tensor imaging (DTI) study, we investigated abnormalities in WM fiber integrity in 56 HIV+ adults with access to cART (mean age: 63.9 ± 3.7 years), compared to 31 matched healthy controls (65.4 ± 2.2 years). Statistical 3D maps revealed the independent effects of HIV diagnosis and age on fractional anisotropy (FA) and diffusivity, but we did not find any evidence for an age by diagnosis interaction in our current sample. Compared to healthy controls, HIV patients showed pervasive FA decreases and diffusivity increases throughout WM. We also assessed neuropsychological (NP) summary z-score associations. In both patients and controls, fiber integrity measures were associated with NP summary scores. The greatest differences were detected in the corpus callosum and in the projection fibers of the corona radiata. These deficits are consistent with published NP deficits and cortical atrophy patterns in elderly people with HIV.
Imaging Genetics Center, Laboratory of Neuro Imaging, Department of Neurology, UCLA School of Medicine, Los Angeles, California.
Talia M
TM
Nir
Neda
N
Jahanshad
Edgar
E
Busovaca
Lauren
L
Wendelken
Krista
K
Nicolas
Paul M
PM
Thompson
Victor G
VG
Valcour
D000368:Aged; D000375:Aging / Q000473:pathology* / Q000502:physiology; D019380:Anti-HIV Agents / Q000627:therapeutic use; D023241:Antiretroviral Therapy, Highly Active; D001284:Atrophy / Q000473:pathology; D003337:Corpus Callosum / Q000473:pathology; D056324:Diffusion Tensor Imaging / Q000295:instrumentation / Q000379:methods*; D005260:Female; D015658:HIV Infections / Q000188:drug therapy / Q000473:pathology* / Q000503:physiopathology; D006801:Humans; D056784:Leukoencephalopathies / Q000473:pathology* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D009412:Nerve Fibers / Q000473:pathology; D009483:Neuropsychological Tests / Q000706:statistics & numerical data
D019380:Anti-HIV Agents
HIV; brain integrity; cART; cognition; diffusion tensor imaging; white matter