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Little is known about the prevalence and burden of HIV associated neurocognitive disorder (HAND) among patients on combination antiretroviral therapy (cART) in sub-Saharan Africa. We estimated the prevalence of HAND in adult Malawians on cART and investigated the relationship between HAND and adherence to cART. HIV positive adults in Blantyre, Malawi underwent a full medical history, neurocognitive test battery, depression score, Karnofsky Performance Score and adherence assessment. The Frascati criteria were used to diagnose HAND and the Global Deficit Score (GDS) was also assessed. Blood was drawn for CD4 count and plasma nevirapine and efavirenz concentrations. HIV negative adults were recruited from the HIV testing clinic to provide normative scores for the neurocognitive battery. One hundred and six HIV positive patients, with median (range) age 39 (18-71) years, 73% female and median (range) CD4 count 323.5 (68-1039) cells/µl were studied. Symptomatic neurocognitive impairment was present in 15% (12% mild neurocognitive disorder [MND], 3% HIV associated dementia [HAD]). A further 55% fulfilled Frascati criteria for asymptomatic neurocognitive impairment (ANI); however factors other than neurocognitive impairment could have confounded this estimate. Neither the symptomatic (MND and HAD) nor asymptomatic (ANI) forms of HAND were associated with subtherapeutic nevirapine/efavirenz concentrations, adjusted odds ratio 1.44 (CI. 0.234, 8.798; p = 0.696) and aOR 0.577 (CI. 0.09, 3.605; p = 0.556) respectively. All patients with subtherapeutic nevirapine/efavirenz levels had a GDS of less than 0.6, consistent with normal neurocognition. Fifteen percent of adult Malawians on cART had a diagnosis of MND or HAD. Subtherapeutic drug concentrations were found exclusively in patients with normal neurocognitive function suggesting HAND did not affect cART adherence. Further study of HAND requires more robust locally derived normative neurocognitive values and determination of the clinical relevance of ANI.

Individuals with previous syphilis may experience cognitive impairment. The goal of this study was to determine if those at high risk for laboratory-defined neurosyphilis are cognitively impaired, and whether treatment based on cerebrospinal fluid (CSF) findings results in better outcomes. Demographics, cognitive complaints and cognitive impairment did not differ between randomized and nonrandomized participants. Two-thirds were cognitively impaired, and impairment was not more common in those with cognitive complaints. The adjusted odds of increased severity of impairment were 3.8 times greater in those with CSF pleocytosis compared to those without. Time to cognitive normalization, improvement or decline did not differ between those who did not undergo LP and those who underwent LP and whose treatment was based on CSF analysis. Taking into account pre-treatment cognitive impairment, the risk of cognitive decline was lower in those with CSF pleocytosis treated for neurosyphilis compared to those without CSF pleocytosis not treated for neurosyphilis, (HR 0.24 (95% CI 0.07-0.88], p = 0.03). In individuals at high risk for laboratory-defined neurosyphilis, cognitive complaints are not a good indicator of cognitive impairment. Severity of cognitive impairment was greater in those with CSF pleocytosis. Identification and treatment of those with neurosyphilis may mitigate subsequent cognitive decline.

Shortly after infection, HIV enters the brain and causes widespread inflammation and neuronal damage, which ultimately leads to neuropsychological impairments. Despite a large body of neuroscience and imaging studies, the pathophysiology of these HIV-associated neurocognitive disorders (HAND) remains unresolved. Previous neuroimaging studies have shown greater activation in HIV-infected patients during strenuous tasks in frontal and parietal cortices, and less activation in the primary sensory cortices during rest and sensory stimulation. High-density magnetoencephalography (MEG) was utilized to evaluate the basic neurophysiology underlying attentive, visual processing in older HIV-infected adults and a matched non-infected control group. Unlike other neuroimaging methods, MEG is a direct measure of neural activity that is not tied to brain metabolism or hemodynamic responses. During MEG, participants fixated on a centrally-presented crosshair while intermittent visual stimulation appeared in their top-right visual-field quadrant. All MEG data was imaged in the time-frequency domain using beamforming. Uninfected controls had increased neuronal synchronization in the 6-12 Hz range within the right dorsolateral prefrontal cortex, right frontal eye-fields, and the posterior cingulate. Conversely, HIV-infected patients exhibited decreased synchrony in these same neural regions, and the magnitude of these decreases was correlated with neuropsychological performance in several cortical association regions. MEG-based imaging holds potential as a noninvasive biomarker for HIV-related neuronal dysfunction, and may help identify patients who have or may develop HAND. Reduced synchronization of neural populations in the association cortices was strongly linked to cognitive dysfunction, and likely reflects the impact of HIV on neuronal and neuropsychological health.

BACKGROUNDPersistence of HIV in sanctuary sites despite antiretroviral therapy (ART) presents a barrier to HIV remission and may affect neurocognitive function. We assessed HIV persistence in cerebrospinal fluid (CSF) and associations with inflammation and neurocognitive performance during long-term ART.METHODSParticipants enrolled in the AIDS Clinical Trials Group (ACTG) HIV Reservoirs Cohort Study (A5321) underwent concurrent lumbar puncture, phlebotomy, and neurocognitive assessment. Cell-associated HIV DNA and HIV RNA (CA-DNA, CA-RNA) were measured by quantitative PCR (qPCR). in peripheral blood mononuclear cells (PBMCs) and in cell pellets from CSF. In CSF supernatant and blood plasma, cell-free HIV RNA was quantified by qPCR with single copy sensitivity, and inflammatory biomarkers were measured by enzyme immunoassay.RESULTSSixty-nine participants (97% male, median age 50 years, CD4 696 cells/mm3, plasma HIV RNA <100 copies/mL) were assessed after a median 8.6 years of ART. In CSF, cell-free RNA was detected in 4%, CA-RNA in 9%, and CA-DNA in 48% of participants (median level 2.1 copies/103 cells). Detection of cell-free CSF HIV RNA was associated with higher plasma HIV RNA (P = 0.007). CSF inflammatory biomarkers did not correlate with HIV persistence measures. Detection of CSF CA-DNA HIV was associated with worse neurocognitive outcomes including global deficit score (P = 0.005), even after adjusting for age and nadir CD4 count.CONCLUSIONHIV-infected cells persist in CSF in almost half of individuals on long-term ART, and their detection is associated with poorer neurocognitive performance.FUNDINGThis observational study, AIDS Clinical Trials Group (ACTG) HIV Reservoirs Cohort Study (A5321), was supported by the National Institutes of Health (NIAID and NIMH).

Background. A single dose of the histone deacetylase inhibitor vorinostat (VOR) up-regulates HIV RNA expression within resting CD4⁺ T cells of treated, aviremic human immunodeficiency virus (HIV)-positive participants. The ability of multiple exposures to VOR to repeatedly disrupt latency has not been directly measured, to our knowledge. Methods. Five participants in whom resting CD4⁺ T-cell-associated HIV RNA (rc-RNA) increased after a single dose of VOR agreed to receive daily VOR Monday through Wednesday for 8 weekly cycles. VOR serum levels, peripheral blood mononudear cell histone acetylation, plasma HIV RNA single-copy assays, rc-RNA, total cellular HIV DNA, and quantitative viral outgrowth assays from resting CD4⁺ T cells were assayed. Results. VOR was well tolerated, with exposures within expected parameters. However, rc-RNA measured after dose 11 (second dose of cycle 4) or dose 22 (second dose of cycle 8) increased significantly in only 3 of the 5 participants, and the magnitude of the rc-RNA increase was much reduced compared with that after a single dose. Changes in histone acetylation were blunted. Results of quantitative viral outgrowth and other assays were unchanged. Conclusions. Although HIV latency is disrupted by an initial VOR dose, the effect of subsequent doses in this protocol was much reduced. We hypothesize that the global effect of VOR results in a refractory period of ≥24 hours. The optimal schedule for VOR administration is still to be defined.

Impairments in working memory are among the most prevalent features of HIV-associated neurocognitive disorders (HAND), yet their origins are unknown, with some studies arguing that encoding operations are disturbed and others supporting deficits in memory maintenance. The current investigation directly addresses this issue by using a dynamic mapping approach to identify when and where processing in working memory circuits degrades. HIV-infected older adults and a demographically-matched group of uninfected controls performed a verbal working memory task during magnetoencephalography (MEG). Significant oscillatory neural responses were imaged using a beamforming approach to illuminate the spatiotemporal dynamics of neuronal activity. HIV-infected patients were significantly less accurate on the working memory task and their neuronal dynamics indicated that encoding operations were preserved, while memory maintenance processes were abnormal. Specifically, no group differences were detected during the encoding period, yet dysfunction in occipital, fronto-temporal, hippocampal, and cerebellar cortices emerged during memory maintenance. In addition, task performance in the controls covaried with occipital alpha synchronization and activity in right prefrontal cortices. In conclusion, working memory impairments are common and significantly impact the daily functioning and independence of HIV-infected patients. These impairments likely reflect deficits in the maintenance of memory representations, not failures to adequately encode stimuli.

Background. We sought to determine the safety of treatment interruption (TI) and to identify parameters that would define patients with human immunodeficiency virus (HIV) for whom TI is safer. Methods. AIDS Clinical Trials Group 5170 was a multicenter, 96-week-long, prospective study of HIV-infected patients receiving antiretroviral therapy (ART) who had CD4⁺ cell counts >350 cells/mm³ and who underwent TI. Results. A total of 167 patients were enrolled. The median nadir in CD4⁺ cell count was 436 cells/mm³. The initial decrease (i.e., during the first 8 weeks) in CD4⁺ cell count after ART interruption was 20 cells/mm³/week; the subsequent decrease was 2.0 cells/mm³/week until week 96. Both the CD4⁺ cell count before enrollment and the increase in CD4⁺ cell count during ART predicted early decrease; later decrease was predicted by the level of interleukin7 at enrollment. A Centers for Disease Control and Prevention (CDC) diagnosis of a category B or C event was made for 2 and 2 patients, respectively (all had CD4⁺ cell counts >350 cells/mm³). At week 96, 17 patients had CD4⁺ cell counts ⩽250 cells/mm³, and 46 patients had resumed ART; 5 patients died (unrelated to HIV or acquired immunodeficiency syndrome). In a multivariate analysis, a higher nadir in CD4⁺ cell count (>400 cells/mm³), a lower HIV load (<50 copies/mL) at the time of TI, and an HIV load ⩽22,000 copies/mL before ART predicted a longer time to the primary end point (CDC category B or C event, death, CD4⁺ cell count ⩽250 cells/mm³, or resumption of ART). Conclusion. Disease progression after TI was low in this cohort. A higher nadir in CD4⁺ cell count, a lower HIV load before ART, and an HIV load ⩽50 copies/mL at the time of TI predicted a longer time to the primary end point.

Shortly after infection, HIV enters the brain and causes widespread inflammation and neuronal damage, which ultimately leads to neuropsychological impairments. Despite a large body of neuroscience and imaging studies, the pathophysiology of these HIV-associated neurocognitive disorders (HAND) remains unresolved. Previous neuroimaging studies have shown greater activation in HIV-infected patients during strenuous tasks in frontal and parietal cortices, and less activation in the primary sensory cortices during rest and sensory stimulation. High-density magnetoencephalography (MEG) was utilized to evaluate the basic neurophysiology underlying attentive, visual processing in older HIV-infected adults and a matched non-infected control group. Unlike other neuroimaging methods, MEG is a direct measure of neural activity that is not tied to brain metabolism or hemodynamic responses. During MEG, participants fixated on a centrally-presented crosshair while intermittent visual stimulation appeared in their top-right visual-field quadrant. All MEG data was imaged in the time-frequency domain using beamforming. Uninfected controls had increased neuronal synchronization in the 6-12 Hz range within the right dorsolateral prefrontal cortex, right frontal eye-fields, and the posterior cingulate. Conversely, HIV-infected patients exhibited decreased synchrony in these same neural regions, and the magnitude of these decreases was correlated with neuropsychological performance in several cortical association regions. MEG-based imaging holds potential as a noninvasive biomarker for HIV-related neuronal dysfunction, and may help identify patients who have or may develop HAND. Reduced synchronization of neural populations in the association cortices was strongly linked to cognitive dysfunction, and likely reflects the impact of HIV on neuronal and neuropsychological health.

Background. We examined associations between suicidality and genotypes that predict plasma efavirenz exposure among AIDS Clinical Trials Group study participants in the United States. Methods. Four clinical trials randomly assigned treatment-naive participants to efavirenz-containing regimens; suicidality was defined as reported suicidal ideation or attempted or completed suicide. Genotypes that predict plasma efavirenz exposure were defined by CYP2B6 and CYP2A6 polymorphisms. Associations were evaluated with weighted Cox proportional hazards models stratified by race/ethnicity. Additional analyses adjusted for genetic ancestry and selected covariates. Results. Among 1833 participants, suicidality was documented in 41 in exposed analyses, and 34 in on-treatment analyses. In unadjusted analyses based on 12 genotype levels, suicidality increased per level in exposed (hazard ratio, 1.11; 95% confidence interval, .96–1.27) and on-treatment 1.16; 1.01–1.34) analyses. In the on-treatment analysis, the association was strongest among white but nearly null among black participants. Considering 3 metabolizer levels (extensive, intermediate and slow), slow metabolizers were at increased risk. Results were similar after baseline covariate-adjustment for genetic ancestry, sex, age, weight, injection drug use history, and psychiatric history or recent psychoactive medication. Conclusions. Genotypes that predict higher plasma efavirenz exposure were associated with increased risk of suicidality. Strength of association varied by race/ethnicity.

Abstract Background Neurocognitive impairment remains a common complication of human immunodeficiency virus (HIV) despite effective antiretroviral therapy (ART). We previously reported improved neurocognitive functioning with ART initiation in 7 resource-limited countries for HIV+ participants from the AIDS Clinical Trials Group (ACTG) 5199 International Neurological Study (INS). Here, we apply normative data from the International Neurocognitive Normative Study (INNS) to INS to provide previously unknown rates of neurocognitive impairment. Methods The A5199 INS assessed neurocognitive and neurological performance within a randomized clinical trial with 3 arms containing World Health Organization first-line recommended ART regimens (ACTG 5175; PEARLS). The ACTG 5271 INNS collected normative comparison data on 2400 high-risk HIV-negative participants from 10 voluntary counseling and testing sites aligned with INS. Normative comparison data were used to create impairment ratings for HIV+ participants in INS; associations were estimated using generalized estimating equations. Results Among 860 HIV+ adults enrolled in ACTG 5199, 55% had no neurocognitive impairment at baseline. Mild neurocognitive impairment was found in 25%, moderate in 17%, and severe in 3% of participants. With the initiation of ART, the estimated odds of impairment were reduced 12% (95% confidence interval, 9%, 14%) for every 24 weeks (P < .0001) on ART. Mild impairment dropped slightly and then remained at about 18% out to week 168. Conclusions Almost half of HIV+ participants had neurocognitive impairment at baseline before ART, based on local norms. With ART initiation, there were significant overall reductions in neurocognitive impairment over time, especially in those with moderate and severe impairments. Clinical Trials Registration NCT00096824. AIDS Clinical Trials Group A5199 compared the neurological and neuropsychological results in 860 human immunodeficiency virus-positive participants from seven resource limited countries randomized on 3 antiretroviral regimens. Participants showed improved neurocognitive function following antiretroviral therapy initiation compared to normative data.