Article

The prevalence and incidence of neurocognitive impairment in the HAART era

Harvard University, Cambridge, Massachusetts, United States
AIDS (Impact Factor: 6.56). 09/2007; 21(14):1915-21. DOI: 10.1097/QAD.0b013e32828e4e27
Source: PubMed

ABSTRACT HAART suppresses HIV viral replication and restores immune function. The effects of HAART on neurological disease are less well understood. The aim of this study was to assess the prevalence and incidence of neurocognitive impairment in individuals who initiated HAART as part of an AIDS clinical trial.
A prospective cohort study of HIV-positive patients enrolled in randomized antiretroviral trials, the AIDS Clinical Trials Group (ACTG) Longitudinal Linked Randomized Trials (ALLRT) study.
We examined the association between baseline and demographic characteristics and neurocognitive impairment among 1160 subjects enrolled in the ALLRT study.
A history of immunosuppression (nadir CD4 cell count < 200 cells/microl) was associated with an increase in prevalent neurocognitive impairment. There were no significant virological and immunological predictors of incident neurocognitive impairment. Current immune status (low CD4 cell count) was associated with sustained prevalent impairment.
The association of previous advanced immunosuppression with prevalent and sustained impairment suggests that there is a non-reversible component of neural injury that tracks with a history of disease progression. The association of sustained impairment with worse current immune status (low CD4 cell count) suggests that restoring immunocompetence increases the likelihood of neurocognitive recovery. Finally, the lack of association between incident neurocognitive impairment and virological and immunological indicators implies that neural injury continues in some patients regardless of the success of antiretroviral therapy on these laboratory measures.

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    • "Combination antiretroviral therapy (cART) has shifted the nature of human immunodefiency virus (HIV)-infection from a terminal illness to a chronic manageable condition with a life expectancy that has gradually approached that of seronegative persons [Antiretroviral Therapy Cohort Collaboration, 2008; Nakagawa et al., 2013]. However , HIV-infected patients remain at a significantly increased risk of developing HIV-associated neurocognitive disorders (HAND), with 35–70% of all patients (treated and untreated) exhibiting at least subtle impairments on tests of neuropsychological function [Antinori et al., 2007; Cysique and Brew, 2009; Gannon et al., 2011; Heaton et al., 2010, 2011; Robertson et al., 2007; Sacktor et al., 2002; Simioni et al., 2010; Tozzi et al., 2007]. Patients with HAND are more likely to be unemployed, have greater problems with medication adherence, and have lower quality of life [Albert et al., 1995; Heaton et al., 1994, 2004; Kaplan et al., 1995; Marcotte et al., 2004; van Gorp et al., 1999]. "
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    Human Brain Mapping 11/2014; 36(3). DOI:10.1002/hbm.22674 · 6.92 Impact Factor
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    • "The widespread use of highly effective combination antiretroviral therapy (cART) has led to a clear reduction in the incidence of HIV-associated dementia (HAD), one of the most severe manifestations of HIV-1 CNS infection [4]. Despite this decrease, HIV-1 associated neurocognitive disorders (HANDs) persist in the cART era [5], with an estimated prevalence of approximately 40-50% [6,7]. Proposed in 2007, current research nosology recognizes three major categories of disease: asymptomatic neurocognitive impairment (ANI), HIV-associated mild neurocognitive disorder (MND), and HAD [8]. "
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    PLoS ONE 06/2014; 9(6):e100196. DOI:10.1371/journal.pone.0100196 · 3.23 Impact Factor
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