Search

BackgroundAnemia is linked to neurocognitive impairment (NCI) in people with HIV (PWH), but its impact within specific ability domains, and in diverse populations with HIV, is uncertain.MethodsParticipants included 1339 PWH enrolled in observational HIV cohort studies with a mean of 3 comprehensive neurocognitive assessments over 30 months. Global and domain-specific neurocognitive function were assessed by the global deficit score and domain deficit score (GDS and DDS, respectively) or as GDS-defined or DDS-defined NCI (GDS ≥ 0.5, DDS > 0.5). Time-dependent associations of anemia or red-cell indices with neurocognitive function were evaluated by multivariable regression.ResultsThe mean age at entry was 43.6 years (85% male, 23.9% Hispanic, 16.7% African ancestry by self-report, and 69.8% virally suppressed). Anemia occurred at entry in 297 (22.2%) and developed subsequently in another 129 (9.6%). Anemia (present in 26.8% of cognitively impaired PWH at entry) and lower hemoglobin were associated with higher (worse) GDS values; the association for anemia persisted after multivariable adjustment and in virally suppressed persons ( P < 0.0001). Anemia was also associated with reduced processing speed, motor function, learning, delayed recall, working memory (all P < 0.01), executive function ( P = 0.021), and verbal fluency ( P = 0.035), and these findings persisted in longitudinal analyses (adjusted P < 0.01 for all domains, except verbal fluency). Higher mean corpuscular volume and mean corpuscular hemoglobin were associated with less impairment in learning and recall (all P < 0.05).ConclusionsAnemia in diverse and virally suppressed PWH associates with reduced neurocognitive performance in multiple domains, cross-sectionally and over time. The impact of identifying and treating anemia to prevent or slow neurocognitive decline in PWH should be prospectively evaluated.

BackgroundTo investigate joint contributions of cognitive and physiologic reserve to neurocognitive SuperAging in older persons with HIV (PWH).MethodsParticipants included 396 older PWH (age range: 50-69 years) who completed cross-sectional neuropsychological and neuromedical evaluations. Using published criteria, participants exhibiting global neurocognition within normative expectations of healthy 25-year-olds were classified as SuperAgers (SA; n = 57). Cognitively normal (CN; n = 172) and impaired (n = 167) participants were classified with chronological age-based norms. Cognitive reserve was operationalized with an estimate of premorbid verbal intelligence, and physiologic reserve was operationalized with a cumulative index of 39 general and HIV-specific health variables. Analysis of variance with confirmatory multinomial logistic regression examined linear and quadratic effects of cognitive and physiologic reserve on SA status, adjusting for chronological age, depression, and race/ethnicity.ResultsUnivariably, SA exhibited significantly higher cognitive and physiologic reserve compared with CN and cognitively impaired ( d s ≥ 0.38, p s < 0.05). Both reserve factors independently predicted SA status in multinomial logistic regression; higher physiologic reserve predicted linear increases in odds of SA, and higher cognitive reserve predicted a quadratic "J-shaped" change in odds of SA compared with CN (ie, odds of SA > CN only above 35th percentile of cognitive reserve).ConclusionsEach reserve factor uniquely related to SA status, which supports the construct validity of our SA criteria and suggests cognitive and physiologic reserve reflect nonoverlapping pathways of neuroprotection in HIV. Incorporation of proxy markers of reserve in clinical practice may improve characterization of age-related cognitive risk and resilience among older PWH, even among PWH without overt neurocognitive impairment.

BackgroundChronic inflammation contributes to the pathogenesis of depression in persons with HIV (PWH). Neopterin, a biomarker of HIV-related immune activation that partially normalizes with antiretroviral therapy (ART), correlates with major depressive disorder (MDD) and subclinical depressive symptoms in persons without HIV and acutely infected, young PWH. The sensitivity of neopterin, however, to both lifetime and current depression is poorly understood in older PWH on suppressive ART.MethodsParticipants were 70 PWH and 35 persons without HIV (HIV-) who were at least 50 years old and completed standardized neurobehavioral and neuromedical assessments. Depressive symptoms in the past 2 weeks, measured with the Beck Depression Inventory-II (BDI-II), and lifetime MDD diagnoses, defined as meeting Diagnostic and Statistical Manual of Mental Disorders-IV criteria for a depressive episode at any point in one's lifetime, were separately modeled as a function of plasma neopterin levels in the full sample and by HIV serostatus.ResultsCompared with HIV- adults, PWH had higher neopterin levels (P < 0.001) and BDI-II scores (P < 0.01) and were more likely to have lifetime MDD (P < 0.01). Higher neopterin related to lifetime MDD, but only in PWH, even after controlling for clinically relevant comorbidities and treatment factors in logistic regression (odds ratio = 3.11, P = 0.002). Higher neopterin correlated with higher BDI-II scores in the full sample (rs = 0.25; P = 0.010), but not within either group (PWH: rs = 0.03, P = 0.819; HIV-: rs = 0.09, P = 0.588).ConclusionNeopterin was associated with lifetime MDD, but not current depressive symptoms in older PWH on suppressive ART. This may reflect a legacy of inflammation-related disruptions to amino acid metabolism and neurotransmitter synthesis, similar to prior observations. Identification of biopsychosocial and resilience factors underlying the null association between neopterin and current depression in older PWH is warranted.

BackgroundCognitive complications persist in persons with HIV during suppressive antiretroviral therapy (ART). Low levels of HIV during ART could contribute to these complications. In this study, we measured cerebrospinal fluid (CSF) HIV using a single-copy assay (SCA) to investigate a possible relationship between low-level HIV and cognition.Design/methodsSCA data were analyzed from 3 consecutively paired CSF-plasma specimens collected over a mean of 456 days from 96 participants on suppressive ART. Using mixed models, the presence of CSF HIV by SCA as a risk factor for worse neurocognitive performance was examined.ResultsAt baseline on the SCA, 45.8% of participants had detectable plasma HIV RNA (median 8 copies/mL and interquartile range = 3-17 among detectable values) and 17.7% had detectable CSF HIV RNA (median CSF concentration= 3 copies/mL and interquartile range= 2-13 among detectable values). The frequency of CSF HIV RNA detection declined over time in CSF (P = 0.018) with a trend toward decline in plasma (P = 0.064). Detectable CSF HIV RNA during the study was associated with worse performance in the domains of recall (P = 0.014) and motor (P = 0.040) and a trend with worse overall global performance (P = 0.078). Integrase inhibitor use, although very infrequent in this cohort, was associated with better performance in 2 domains.ConclusionsLow-level CSF HIV RNA declines with time but is associated with worse cognitive performance in 2 domains. Additional research is needed to better understand the relationship between HIV RNA persistence during long-term ART and central nervous system complications in persons with HIV.

BackgroundEven in the era of suppressive antiretroviral therapy, people with HIV (PWH) suffer greater exposure to inflammation than their uninfected peers. Although poor social support and social isolation have been linked to systemic inflammation in the general population, it is not known whether this is true also among PWH.MethodsPeople with and without HIV infection were enrolled in a community-based, single-center study. Primary predictors were the Medical Outcomes Study Social Support Survey, and outcomes were a panel of inflammatory biomarkers (ICAM-1, MCP-1, IL-6, IL-8, IP-10, C-reactive protein, D-dimer, VEGF, sCD14, and uPAR) in blood plasma and cerebrospinal fluid (CSF).ResultsPWH had worse positive social support (P = 0.0138) and affectionate support (P = 0.0078) than did HIV- individuals. A factor analysis was used to group the biomarkers into related categories separately for each fluid. Levels of 3 of the 4 plasma factors were significantly higher in PWH than HIV- (ps = 0.007, 0.001, and 0.0005, respectively). Levels of 1 of the 3 CSF factors also were significantly higher in PWH than HIV- (P = 0.0194). In the combined PWH and HIV- cohort, poorer social support was associated with higher levels of a factor in plasma loading on MCP-1, IL-8, and VEGF (P = 0.020) and with a CSF factor loading on MCP-1 and IL-6 (P = 0.006).ConclusionThese results suggest that enhancing social support might be an intervention to reduce inflammation and its associated adverse outcomes among PWH.

BackgroundAcross many settings, lack of virologic control remains common in people with HIV (PWH) because of late presentation and lack of retention in care. This contributes to neuronal damage and neurocognitive impairment, which remains prevalent. More evidence is needed to understand these outcomes in both PWH and people without HIV (PWOH).MethodsWe recruited PWH initiating antiretroviral therapy and PWOH at 2 sites in the United States. One hundred eight adults were enrolled (56 PWOH and 52 PWH), most of whom had a second assessment at least 24 weeks later (193 total assessments). Tumor necrosis factor alpha, monocyte chemotactic protein-1 (MCP-1), neopterin, soluble CD14, and neurofilament light chain protein (NFL) were measured in plasma and cerebrospinal fluid (CSF). Using multivariate models including Bayesian model averaging, we analyzed factors associated with global neuropsychological performance (NPT-9) and CSF NFL at baseline and over time.ResultsAt baseline, higher CSF MCP-1 and plasma sCD14 were associated with worse NPT-9 in PWH, while CSF HIV RNA decrease was the only marker associated with improved NPT-9 over time. Among PWH, higher CSF neopterin was most closely associated with higher NFL. Among PWOH, higher CSF MCP-1 was most closely associated with higher NFL. After antiretroviral therapy initiation, decrease in CSF MCP-1 was most closely associated with NFL decrease.ConclusionMonocyte-associated CSF biomarkers are highly associated with neuronal damage in both PWH and PWOH. More research is needed to evaluate whether therapies targeting monocyte-associated inflammation may ameliorate HIV-associated neurobehavioral diseases.

ObjectiveHIV disease and methamphetamine (METH) dependence share overlapping mechanisms of neurotoxicity that preferentially compromise monoamine-rich frontostriatal circuitry. However, norepinephrine (NE) function is poorly understood in HIV and METH dependence. We evaluated associations between cerebrospinal fluid (CSF) NE and HIV, METH dependence, and neurocognition.MethodsParticipants included 125 adults, stratified by HIV serostatus (HIV+/HIV-) and recent METH dependence (METH+/METH-), who underwent comprehensive neurocognitive testing and lumbar puncture. CSF NE was assayed using high-performance liquid chromatography. Multivariable regression modelled NE as a function of HIV, METH, and their interaction, adjusting for demographic and clinical factors. Pearson correlations examined relationships between NE and demographically-adjusted neurocognitive domain scores.ResultsHIV significantly interacted with METH (P < 0.001) such that compared with HIV-/METH-, CSF NE was markedly elevated in the single risk-groups (HIV+/METH-: d = 0.96; HIV-/METH+: d = 0.79) and modestly elevated in the dual-risk group (HIV+/METH+: d = 0.48). This interaction remained significant after adjustment for lifetime depression, antidepressant use, and race/ethnicity. In the full sample, higher NE levels significantly correlated with worse global function (r = -0.19), learning (r = -0.23), and delayed recall (r = -0.18). Similar relationships between higher NE and worse neurocognition were detected in the METH- groups (ie, HIV-/METH- and HIV+/METH-) and in the virally-suppressed persons HIV+ subgroup, but not in the METH+ groups (ie, HIV-/METH+, HIV+/METH+).DiscussionHIV and METH independently, but not additively, relate to noradrenergic excess in the central nervous system, and perturbations to noradrenergic function may represent a pathophysiological mechanism of HIV-related neurocognitive dysfunction. Consistent with prior reports that noradrenergic excess compromises hippocampal and prefrontal function, higher NE related to worse neurocognition, even among successfully treated persons with HIV. Pharmacological and psychosocial interventions that stabilize NE function may improve neurocognition in persons with HIV.

BackgroundInflammatory processes have been suggested to underlie early neurologic abnormalities among persons living with HIV (HIV-positive), such as deficits in complex motor function, that are purported to remit with effective antiretroviral therapy (ART). We hypothesized that HIV will have negative direct and indirect effects through inflammation on complex motor performance.MethodsThe sample consisted of 90 ART-treated virally suppressed HIV-positive and 94 HIV-negative adults, aged 36-65 years, with balanced recruiting in each age decade (36-45, 46-55, and 56-65). Biomarkers of inflammation (d-dimer, IL-6, MCP-1/CCL2, sCD14, and TNF-α) were measured, and a composite inflammation burden score was calculated. Complex motor performance was evaluated using the Grooved Pegboard Test.ResultsThe HIV-positive group had worse complex motor performance (P = 0.001; Hedges g = -0.49) and a higher average inflammation burden composite score (P < 0.001; Hedges g = 0.78) than the HIV-negative group. Path analyses indicated that the indirect effect of HIV disease on complex motor performance through inflammation burden was statistically significant, accounting for 15.1% of the effect of HIV on complex motor performance.ConclusionsAlthough neurologic findings (eg, deficits in motor speed/dexterity) commonly associated with HIV infection typically remit with ART, our analysis indicates that inflammation plays an important role in worse complex motor skills among HIV-positive adults. Future studies of strategies for managing chronic inflammation in HIV should consider using an inflammation burden composite and examining its effect on complex motor performance.

ObjectiveThe study aims to determine whether cystatin C is associated with HIV disease and HIV-associated neurocognitive impairment (NCI).MethodsParticipants included 124 (HIV+ n = 77; HIV- n = 47) older adults (age ≥ 50 years) examined at the University of California, San Diego HIV Neurobehavioral Research Program. Cystatin C, a biomarker of kidney functioning that has been linked to poor health outcomes, was measured in blood. Participants completed a comprehensive neurocognitive assessment that was used to define both global and domain NCI.ResultsThe HIV+ group had significantly higher cystatin C concentrations than the HIV- group (d = 0.79 P < 0.001). Among HIV+ participants, those with NCI had higher cystatin C concentrations than those without NCI (d = 0.42, P = 0.055), particularly among participants taking tenofovir (d = 0.78, P = 0.004). A receiver-operator characteristic curve identified that cystatin C levels ≥0.75 mg/L were associated with NCI in the HIV+ group. Using this binary variable and including relevant covariates, multivariate modeling confirmed that NCI was associated with higher cystatin C levels (OR = 3.0; P = 0.03).ConclusionsOur results confirm that HIV+ older adults have higher cystatin C than HIV- older adults and further identify that cystatin C may be associated with NCI in this population, particularly if they use tenofovir. This blood biomarker may be a useful clinical tool to identify older HIV+ persons at greater risk for cognitive decline.

BackgroundHIV is associated with elevated markers of vascular remodeling that may contribute to arterial fibrosis and stiffening and changes in pulse pressure (PP). These changes may, in turn, deleteriously affect autoregulation of cerebral blood flow and neurocognitive function.MethodsTo evaluate these mechanisms, we studied markers of vascular remodeling, PP, and neurocognitive function among older (≥50 years of age) HIV-infected (HIV+, n = 72) and HIV-seronegative (HIV-, n = 36) adults. Participants completed standardized neurobehavioral and neuromedical assessments. Neurocognitive functioning was evaluated using a well-validated comprehensive battery. Three plasma biomarkers of vascular remodeling (ie, angiopoietin 2, Tie-2, and vascular endothelial growth factor, VEGF) were collected.ResultsHIV+ and HIV- participants had similar levels of plasma angiopoietin 2 (P = 0.48), Tie-2 (P = 0.27), VEGF (P = 0.18), and PP (P = 0.98). In a multivariable regression model, HIV interacted with Tie-2 (β = 0.41, P < 0.01) and VEGF (β = -0.43, P = 0.01) on neurocognitive function, such that lower Tie-2 and higher VEGF values were associated with worse neurocognitive function for HIV+ participants. Greater Tie-2 values were associated with increased PP (r = 0.31, P < 0.01). In turn, PP demonstrated a quadratic association with neurocognitive function (β = -0.33, P = 0.01), such that lower and higher, relative to mean sample, PP values were associated with worse neurocognitive function.ConclusionsThese findings indicate that vascular remodeling and altered cerebral blood flow autoregulation contribute to neurocognitive function. Furthermore, HIV moderates the association between vascular remodeling and neurocognitive function but not the association between PP and neurocognitive function.

ObjectiveThe Veterans Aging Cohort Study (VACS) Index is predictive of mortality and combines age, traditional HIV biomarkers (HIV-1 plasma RNA and current CD4 count), and non-HIV biomarkers (indicators of renal and liver function, anemia, and hepatitis C coinfection). We examined the association between the VACS Index and HIV-associated neurocognitive impairment (NCI).Design and methodsParticipants included 601 HIV-infected adults enrolled in cohort studies at the University of California, San Diego, HIV Neurobehavioral Research Program (ages: 18-76 years; 88% male; 63% white; median current CD4 = 364 cells/mm; 63% on antiretroviral therapy; AIDS = 64%). Biomarkers used in calculating the VACS Index were measured in prospectively collected blood samples using conventional laboratory methods. NCI was defined using global and seven domain deficit scores.ResultsHigher VACS Index scores were associated with concurrent risk for global NCI [P < 0.001; odds ratio = 1.21, confidence interval (CI): 1.12 to 1.32], even when adjusting for psychiatric comorbidities. This relation was statistically significant for most cognitive domains in adjusted models. Furthermore, the VACS Index predicted concurrent NCI beyond nadir CD4 and estimated duration of infection. Older age, lower hemoglobin, and lower CD4 counts were the VACS components most strongly linked to NCI.ConclusionsThe findings extend previous research on the potential usefulness of the VACS Index in predicting HIV-associated outcomes to include NCI. Although the effect size was relatively small, our findings suggest that demographic information, HIV-disease factors, and common comorbidities might each play important roles in the clinical manifestation of cognitive impairment among HIV-infected individuals. Additional research is needed to determine if a more sensitive and specific index can be developed.