title: Disrupted cerebral metabolite levels and lower nadir CD4 + counts are linked to brain volume deficits in 210 HIV-infected patients on stable treatment.
abstract: Cognitive impairment and brain injury are common in people with HIV/AIDS, even when viral replication is effectively suppressed with combined antiretroviral therapies (cART). Metabolic and structural abnormalities may promote cognitive decline, but we know little about how these measures relate in people on stable cART. Here we used tensor-based morphometry (TBM) to reveal the 3D profile of regional brain volume variations in 210 HIV + patients scanned with whole-brain MRI at 1.5 T (mean age: 48.6 ± 8.4 years; all receiving cART). We identified brain regions where the degree of atrophy was related to HIV clinical measures and cerebral metabolite levels assessed with magnetic resonance spectroscopy (MRS). Regional brain volume reduction was linked to lower nadir CD4 + count, with a 1-2% white matter volume reduction for each 25-point reduction in nadir CD4 +. Even so, brain volume measured by TBM showed no detectable association with current CD4 + count, AIDS Dementia Complex (ADC) stage, HIV RNA load in plasma or cerebrospinal fluid (CSF), duration of HIV infection, antiretroviral CNS penetration-effectiveness (CPE) scores, or years on cART, after controlling for demographic factors, and for multiple comparisons. Elevated glutamate and glutamine (Glx) and lower N-acetylaspartate (NAA) in the frontal white matter, basal ganglia, and mid frontal cortex - were associated with lower white matter, putamen and thalamus volumes, and ventricular and CSF space expansion. Reductions in brain volumes in the setting of chronic and stable disease are strongly linked to a history of immunosuppression, suggesting that delays in initiating cART may result in imminent and irreversible brain damage.
authors.affiliation: Imaging Genetics Center, Laboratory of Neuro Imaging, Dept. of Neurology, UCLA School of Medicine, Los Angeles, CA, USA.
authors.forename: Xue
authors.initials: X
authors.lastname: Hua
authors.forename: Christina P
authors.initials: CP
authors.lastname: Boyle
authors.forename: Jaroslaw
authors.initials: J
authors.lastname: Harezlak
authors.forename: David F
authors.initials: DF
authors.lastname: Tate
authors.forename: Constantin T
authors.initials: CT
authors.lastname: Yiannoutsos
authors.forename: Ron
authors.initials: R
authors.lastname: Cohen
authors.forename: Giovanni
authors.initials: G
authors.lastname: Schifitto
authors.forename: Assawin
authors.initials: A
authors.lastname: Gongvatana
authors.forename: Jianhui
authors.initials: J
authors.lastname: Zhong
authors.forename: Tong
authors.initials: T
authors.lastname: Zhu
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Taylor
authors.forename: Thomas B
authors.initials: TB
authors.lastname: Campbell
authors.forename: Eric S
authors.initials: ES
authors.lastname: Daar
authors.forename: Jeffry R
authors.initials: JR
authors.lastname: Alger
authors.forename: Elyse
authors.initials: E
authors.lastname: Singer
authors.forename: Steve
authors.initials: S
authors.lastname: Buchthal
authors.forename: Arthur W
authors.initials: AW
authors.lastname: Toga
authors.forename: Bradford
authors.initials: B
authors.lastname: Navia
authors.forename: Paul M
authors.initials: PM
authors.lastname: Thompson
keywords: Combined antiretroviral therapy; HIV; Magnetic resonance imaging; Nadir CD4 +; Proton magnetic resonance spectroscopy; Tensor-based morphometry