Longitudinal Trajectories of Brain Volume and Cortical Thickness in Treated and Untreated Primary Human Immunodeficiency Virus Infection

Abstract

Subcortical atrophy and cortical thinning occur during untreated infection but may be arrested by cART. These findings emphasize the importance of early cART.

Different roles of frontal versus striatal atrophy in HIV‐associated neurocognitive disorders

“…The presumably ongoing viral replication in the caudate nuclei, along with the associated neurotoxicity due to neuroinflammation (and/or neurotoxic side effects of antiretroviral agents), might result in growing neuronal injury in the caudate (Chang et al, ; Wang et al, ), which may eventually lead to detectable reduction in caudate volume and neurocognitive performance. Our hypothesis of this ongoing caudate injury model is also supported by findings from other studies: (a) Studies with postmortem brains and SIV models have suggested a high concentration of virus in the caudate nuclei (Kumar, Borodowsky, Fernandez, Gonzalez, & Kumar, ; Perez et al, ) and the basal ganglia in general, and the viral load in the caudate (along with the frontal cortex and the globus pallidus) correlates with neurocognitive impairment (Kumar et al, ); (b) Studies have found that the viral load in plasma and/or CSF correlates with caudate volume or neuronal injury in the caudate (Dewey et al, ; Krivine et al, ; Wang et al, ); (c) Studies have suggested a correlation between caudate volume and the estimated duration of HIV‐disease (Ances et al, ; Becker et al, ), implicating a gradual and ongoing decline in caudate volume after seroconversion, despite being on cART; (d) A recent longitudinal study with HIV+ older adults have found that not only the annualized rate of atrophy is higher in the caudate (0.74%) than any other brain regions in HIV (including the frontal lobe (0.48%) and the globus pallidus (0.73%)), but also the difference in the annualized rates of atrophy between HIV+ older adults and age‐matched controls is the largest in the caudate (ln [(1–0.0003)/(1–0.0074)] = ln (0.9997)−ln [0.9926] = 0.0071), followed by total cortical GM (0.0049) and the frontal lobe (0.0047), and is “twice” more than the globus pallidus (0.0034) (Clifford et al, ), suggesting that the caudate remains one of the most vulnerable and affected brain regions in HIV in the cART era; (e) Another longitudinal study also found that HIV+ adults with chronic infection have smaller caudate, putamen, and other subcortical regions than HIV+ adults with acute infection (Sanford et al, ), suggesting an ongoing neural injury to the caudate/striatum.…”

“…the frontal lobe (0.0047), and is "twice" more than the globus pallidus (0.0034) (Clifford et al, 2017), suggesting that the caudate remains one of the most vulnerable and affected brain regions in HIV in the cART era; (e) Another longitudinal study also found that HIV+ adults with chronic infection have smaller caudate, putamen, and other subcortical regions than HIV+ adults with acute infection (Sanford et al, 2018), suggesting an ongoing neural injury to the caudate/striatum.…”

Sensitivity of ventrolateral posterior thalamic nucleus to back pain in alcoholism and CD4 nadir in HIV

“…The prevalence of HAD on the severe end of the spectrum has declined with antiretroviral therapy (ART) (Baker et al, 2015;Gates & Cysique, 2016), but mild to moderate cognitive deficits in HIV remain an issue (Manji, Jager, & Winston, 2013;Underwood et al, 2017;Vivithanaporn et al, 2010). Accelerated loss of brain tissue, specifically, in frontal and sensorimotor neocortices, thalamus, and hippocampus-related to disease duration and CD4 nadir (Cohen et al, 2010;Pfefferbaum et al, 2014)-may represent a risk factor for premature cognitive compromise if not dementia (Ances, Ortega, Vaida, Heaps, & Paul, 2012;Pfefferbaum et al, 2014;Pfefferbaum et al, 2018;Sanford et al, 2018). In seeking a neural substrate for HAD, an early imaging study in HIV-infected individuals found no relation between neuropsychological test performance and hippocampal volume (Kieburtz et al, 1996); a later stereological study found no statistically significant differences in hippocampal neuronal number between nine HIV/AIDS patients and 10 controls (Korbo & West, 2000).…”

Is successful HIV therapy a Pyrrhic victory for the brain?

“…However, neurocognitive performance gaps may accrue early in infection, then evolve in parallel with normal age-related changes. Successfully treated HIV patients (in whom it seems CA virus is prevalent) have a similar aging pace as the general population in some but not all studies (9)(10)(11)(12). In part because the HIV population has complex comorbidities that contribute and likely dominate the impact of HIV itself, assembling high-quality longitudinal, well-controlled patient studies has been difficult.…”