Substance use is a risk factor for neurocognitive deficits and neuropsychiatric distress in acute and early HIV infection.
ABSTRACT The acute and early stages of HIV infection (AEH) are characterized by substantial viral replication, immune activation, and alterations in brain metabolism. However, little is known about the prevalence and predictors of neurocognitive deficits and neuropsychiatric disturbances during this period. The present study examined the impact of demographic, HIV disease, and substance use factors on HIV-associated neurocognitive impairment and self-reported neuropsychiatric distress among 46 antiretroviral-naive adults with median duration of infection of 75 days relative to a sample of 21 HIV seronegative (HIV-) adults with comparable demographics and risk factors. Participants were administered a brief neurocognitive battery that was adjusted for demographics and assessed executive functions, memory, psychomotor speed, and verbal fluency, as well as the Profile of Mood States, a self-report measure of neuropsychiatric distress. Odds ratios revealed that AEH participants were nearly four times more likely than their seronegative counterparts to experience neurocognitive impairment, particularly in the areas of learning and information processing speed. Similarly, AEH was associated with a nearly fivefold increase in the odds of neuropsychiatric distress, most notably in anxiety and depression. Within the AEH sample, HIV-associated neurocognitive impairment was associated with problematic methamphetamine use and higher plasma HIV RNA levels, whereas neuropsychiatric distress was solely associated with high-risk alcohol use. Extending prior neuroimaging findings, the results from this study indicate that HIV-associated neurocognitive impairment and neuropsychiatric distress are highly prevalent during AEH and are associated with high-risk substance use.
SourceAvailable from: Peter Jesse Gaskill[Show abstract] [Hide abstract]
ABSTRACT: Macrophages are the primary cell type infected with HIV in the central nervous system, and infection of these cells is a major component in the development of neuropathogenesis and HIV-associated neurocognitive disorders. Within the brains of drug abusers, macrophages are exposed to increased levels of dopamine, a neurotransmitter that mediates the addictive and reinforcing effects of drugs of abuse such as cocaine and methamphetamine. In this study we examined the effects of dopamine on HIV entry into primary human macrophages. Exposure to dopamine during infection increased the entry of R5 tropic HIV into macrophages, irrespective of the concentration of the viral inoculum. The entry pathway affected was CCR5 dependent, as antagonizing CCR5 with the small molecule inhibitor TAK779 completely blocked entry. The effect was dose-dependent and had a steep threshold, only occurring above 108 M dopamine. The dopamine-mediated increase in entry required dopamine receptor activation, as it was abrogated by the pan-dopamine receptor antagonist flupenthixol, and could be mediated through both subtypes of dopamine receptors. These findings indicate that the effects of dopamine on macrophages may have a significant impact on HIV pathogenesis. They also suggest that drug-induced increases in CNS dopamine may be a common mechanism by which drugs of abuse with distinct modes of action exacerbate neuroinflammation and contribute to HIV-associated neurocognitive disorders in infected drug abusers.PLoS ONE 09/2014; 9(9):e108232. DOI:10.1371/journal.pone.0108232 · 3.53 Impact Factor
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ABSTRACT: Excessive alcohol use is common among people living with HIV. Given the growing prevalence of older HIV+ adults and observations indicating higher risk for neurocognitive impairment in older adults with either HIV infection or alcoholism, an increased understanding of their combined impact in the context of this increasingly aged population is crucial. We conducted comprehensive neurocognitive assessment in 112 older HIV+ individuals aged 50 to 69 years. Regression analyses were conducted to examine the interaction between age and the presence of lifetime alcohol dependence on neurocognitive measures, controlling for years of education, hepatitis C serostatus, and lifetime non-alcohol substance use disorder. Significant interactions of age and alcohol dependence history were found for global neurocognitive function, which was driven by the domains of executive function, processing speed, and semantic memory. Follow-up analyses indicated adverse effects of alcohol use history on neurocognitive measures that were evident only in HIV+ individuals 60 years and older. While mounting evidence in younger cohorts indicates adverse synergistic HIV/alcohol effects on neurocognitive function, our novel preliminary findings in this elderly HIV+ cohort demonstrated the importance of even a relatively distant alcohol use history on the expression of HIV-associated neurocognitive disorders that may not become apparent until much later in life.Journal of NeuroVirology 09/2014; 20(5). DOI:10.1007/s13365-014-0277-z · 3.32 Impact Factor
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ABSTRACT: Drug abuse is a major comorbidity of HIV infection and cognitive disorders are often more severe in the drug abusing HIV infected population. CD14+CD16+ monocytes, a mature subpopulation of peripheral blood monocytes, are key mediators of HIV neuropathogenesis. Infected CD14+CD16+ monocyte transmigration across the blood brain barrier mediates HIV entry into the brain and establishes a viral reservoir within the CNS. Despite successful antiretroviral therapy, continued influx of CD14+CD16+ monocytes, both infected and uninfected, contributes to chronic neuroinflammation and the development of HIV associated neurocognitive disorders (HAND). Drug abuse increases extracellular dopamine in the CNS. Once in the brain, CD14+CD16+ monocytes can be exposed to extracellular dopamine due to drug abuse. The direct effects of dopamine on CD14+CD16+ monocytes and their contribution to HIV neuropathogenesis are not known. In this study, we showed that CD14+CD16+ monocytes express mRNA for all five dopamine receptors by qRT-PCR and D1R, D5R and D4R surface protein by flow cytometry. Dopamine and the D1-like dopamine receptor agonist, SKF38393, increased CD14+CD16+ monocyte migration that was characterized as chemokinesis. To determine whether dopamine affected cell motility and adhesion, live cell imaging was used to monitor the accumulation of CD14+CD16+ monocytes on the surface of a tissue culture dish. Dopamine increased the number and the rate at which CD14+CD16+ monocytes in suspension settled to the dish surface. In a spreading assay, dopamine increased the area of CD14+CD16+ monocytes during the early stages of cell adhesion. In addition, adhesion assays showed that the overall total number of adherent CD14+CD16+ monocytes increased in the presence of dopamine. These data suggest that elevated extracellular dopamine in the CNS of HIV infected drug abusers contributes to HIV neuropathogenesis by increasing the accumulation of CD14+CD16+ monocytes in dopamine rich brain regions.PLoS ONE 02/2015; 10(2):e0117450. DOI:10.1371/journal.pone.0117450 · 3.53 Impact Factor