Defining neurocognitive impairment in HIV: deficit scores versus clinical ratings

A Cross-Sectional Study to Evaluate the Effects of Age and Duration of HIV Infection on Anxiety and Depression in Cisgender Men

This observational cross-sectional study of 152 people with HIV (PWH) examined the effects of age and estimated duration of HIV infection (EDI) on depressive and anxiety symptoms. All participants were cisgender men and completed the Profile of Moods State (POMS), a self-report inventory of current (i.e., past week) mood states. Overall, study results confirmed higher levels of anxiety and depression in PWH compared to individuals without HIV. Age group (< 50 or ≥ 50 years) moderated the effect of EDI (< 3 or ≥ 3 years) on mood disturbance. Specifically, younger PWH with early diagnosed infection exhibited the highest levels of depression and anxiety, whereas depression and anxiety were attenuated in older PWH with early infection such that their POMS scores did not significantly differ from the HIV-negative and chronically HIV-infected groups. Despite the small sample size and other important limitations in our study design, our preliminary findings confirm previous observations that older people may have some adaptive ability to better handle the acute psychological stressors associated with recent HIV infection.

Cardio-ankle vascular index of increased arterial wall stiffness is associated with neurocognitive impairment in well-controlled HIV

OBJECTIVES

HIV-associated neurocognitive disorders (HAND) remain prevalent in people living with HIV (PLWH) despite widespread use of combined antiretroviral therapy (ART). Vascular disease contributes to the pathogenesis of HAND, but traditional vascular risk factors do not fully explain the relation between vascular disease and HAND. A more direct measure of vascular dysfunction is needed. This cross-sectional study tested whether the cardio-ankle vascular index (CAVI), a novel method to assess arterial stiffness, is associated with HAND among PLWH.

METHODS

Participants included 75 non-diabetic adults with well-controlled HIV from an outpatient HIV clinic. We assessed the relation between CAVI and neurocognitive impairment (NCI). The latter was primarily characterized by the Frascati criteria and secondarily (post hoc) using the Global Deficit Score (GDS). Logistic regression models tested whether high CAVI (≥ 8) was independently associated with NCI when controlling for potential confounders.

RESULTS

Participants (M_age  = 45.6 ± 8.3 years; 30.1% male) had few traditional cardiovascular disease (CVD) risk factors (hypertension, n = 7; dyslipidaemia, n = 34; body mass index ≥ 25 kg/m² , n = 12; smoking history, n = 13; 2.2% mean 10-year risk of CVD or stroke). Twelve (16%) participants had high CAVI, which was independently associated with meeting Frascati criteria for NCI [n = 39, odds ratio (OR) = 7.6, p = 0.04], accounting for age, education, gender, income, CD4 nadir, recent CD4 and traditional CVD risk factors. High CAVI was also associated with NCI as reflected by higher GDS (OR = 17.4, p = 0.02).

CONCLUSIONS

Cardio-ankle vascular index is a promising measure of vascular dysfunction that may be independently associated with NCI in relatively healthy PLWH. Larger studies should test the utility of CAVI in predicting NCI/decline in PLWH.

Can Individualized-Targeted Computerized Cognitive Training Benefit Adults with HIV-Associated Neurocognitive Disorder? The Training on Purpose Study (TOPS)

Half of people with HIV (PWH) have HIV-associated neurocognitive disorder (HAND). This study examined whether cognition can be improved using a framework targeting impaired individual cognitive domains in PWH with HAND. In this two-group pre-post experimental design study, 88 adults with HAND were randomized to either: (1) a no-contact control group (n = 40) or (2) the Individualized-Targeted Cognitive Training group (n = 48). Baseline cognitive performance was assessed on eight cognitive domains. A theoretical framework was used to determine the two cognitive domains selected for training. With priority on speed of processing (SOP) and attention impairments, participants received SOP and/or attention training if such impairments were detected; if not, participants were assigned to cognitive training in one/two of the least impaired cognitive domains contributing to their HAND diagnosis. Global cognitive score was slightly improved following training (p = 0.256; d = - 0.21), but it was not significant. Significant improvements were observed on SOP following training in that domain (SOP; d = - 0.88; p = 0.011). SOP training also improved functioning in other cognitive domains. This individualized cognitive intervention did not change HAND status, but it did result in improved SOP, in turn yielding improvement in other cognitive domains.

Plasma Cytokine Biomarker Cutoff Values for HIV-Associated Neurocognitive Impairment in Adults

Diagnosing HIV-associated neurocognitive impairment in most high-burden, but resource-constrained, settings is difficult due to the unavailability of specialist neurologists and neuropsychologists in primary health care centers. New tests that are easy to perform, based on virological and host immune response biomarkers, may be valuable in the diagnosis of HIV-associated neurocognitive disorder. The receiver operator characteristic curve analysis was used to investigate the diagnostic accuracy of threshold/cutoff concentrations for the peripheral lymphocyte proviral load and plasma biomarkers as diagnostic candidates for neurocognitive impairment in 133 HIV-infected individuals, using global deficit scores as the clinical gold standard. Forty-five (33.83%) of the participants had HIV-associated neurocognitive impairment, with 17.29% being mildly impaired and 16.54% moderately impaired. IL-2 had the best performance as a diagnostic tool for neurocognitive impairment with sensitivity of 67% and specificity of 52%, while the lowest performance was IL-6 with 65% sensitivity and 39% specificity. MIP-1α had the highest precision for the cutoff value, as indicated by the narrow 95% confidence interval (CI) (2.23-3.27), followed by IL-2 with 95% CI (3.02-5.12). RANTES had least precision, as shown by the widest 95% CI (135-9,487.61). For clinical markers of HIV diagnosis and monitoring, the lymphocyte proviral load cutoff value of 145 genome copies/million cells had the highest accuracy with 60% sensitivity and 51% specificity. The plasma viral load had an imperfect balance of 46% sensitivity and 78% specificity. The study demonstrated low to medium diagnostic accuracy of plasma cytokine biomarker cutoff values for defining neurocognitive impairment in people living with HIV.

Development of a Nomogram-Based Tool to Predict Neurocognitive Impairment Among HIV-positive Charter Participants

Background:

Despite the widespread use of combination antiretroviral therapy (cART), HIV-associated neurocognitive impairment (NCI) persists in people living with HIV (PLWH). Studies have generated inconsistent results regarding etiological factors for NCI in PLWH. Furthermore, a user-friendly and readily available predictive tool is desirable in clinical practice to screen PLWH for NCI.

Objective:

This study aimed to identify factors associated with NCI using a large and diverse sample of PLWH and build a nomogram based on demographic, clinical, and behavioral variables.

Methods:

We performed Bayesian network analysis using a supervised learning technique with the Markov Blanket (MB) algorithm. Logistic regression was also conducted to obtain the adjusted regression coefficients to construct the nomogram.

Results:

Among 1,307 participants, 21.6% were neurocognitively impaired. During the MB analysis, age provided the highest amount of mutual information (0.0333). Logistic regression also showed that old age (>50 vs. ≤50 years) had the strongest association (OR=2.77, 95% CI=1.99-3.85) with NCI. The highest possible points on the nomogram were 626, translated to a nomogram-predicted probability of NCI to be approximately 0.95. The receiver operating characteristic (ROC) curve's concordance index was 0.75, and the nomogram's calibration plot exhibited an excellent agreement between observed and predicted probabilities.

Conclusion:

The nomogram used variables that can be easily measured in clinical settings and, thus, easy to implement within a clinic or web-interface platform. The nomogram may help clinicians screen for patients with a high probability of having NCI and thus needing a comprehensive neurocognitive assessment for early diagnosis and appropriate management.

An assessment of factors associated with neurocognitive decline in people living with HIV

Despite the widespread use of combination antiretroviral therapy (cART), HIV-associated neurocognitive impairment (NCI) remains a health concern. However, limited research has been done to identify factors associated with neurocognitive decline. We assessed risk factors associated with neurocognitive decline in people living with HIV using a definition of decline that is statistically easy to adopt, is based on a commonly used neuropsychological cut-off and may be clinically relevant. Cox proportional hazards modeling was performed using the CNS HIV Antiretroviral Therapy Effects Research (CHARTER) study database. 581 participants were followed for up to 12 years. Neurocognitive decline was defined as the first observed drop in global T-scores of at least 2.67. Lifetime methamphetamine use had the strongest association with neurocognitive decline (adjusted Hazard Ratio; aHR = 1.48; 95% CI = 0.92-2.39) followed by no current antiretroviral medication use (aHR = 1.32; 95% CI = 0.91-1.92). Other risk factors included Hispanic ethnicity, lifetime history of major depressive disorder, lifetime cannabis use, hepatitis-C infection, and difficulty eating, dressing, bathing, or using the toilet. Results indicate that consistent use of ART may be of high significance to preserving neurocognition. Furthermore, Hispanic patients, those with a history of depression and substance use, and those having difficulty in essential activities of daily living may require vigilant follow-up.

Driving habits, cognition, and health-related quality of life in middle-aged and older adults with HIV

Cognitive impairment is known to increase with aging in people living with HIV (PLWH). Impairment in cognitive domains required for safe driving may put PLWH at risk for poor driving outcomes, decreased mobility, and health-related quality of life (HRQoL). This study described the driving behaviors of middle-aged and older PLWH and examined correlations between driving behaviors and cognitive functioning (Aim 1), and driving behaviors and HRQoL domains (Aim 2). A sample of 260 PLWH ages 40 and older completed a comprehensive assessment including a battery of cognitive tests, an HRQoL measure, and a measure of self-reported driving habits. Associations between driving habits, cognitive function, and HRQoL domains were examined. While 212 (81.54%) participants reported currently driving, only 166 (63.85%) possessed a driver's license. Several significant correlations emerged between driving habits and both cognitive and HRQoL variables, with a general pattern suggesting that current greater driving exposure was associated with better cognitive functioning and HRQoL. Given consistent associations that emerged between the social functioning HRQoL domain and several driving habits, multivariable regression was conducted to examine the unique association between an index of greater driving exposure (i.e., days driven per week) and social functioning, adjusting for potential confounders (race, income, education, depression, and global cognition). Results showed that more days driven per week was a significant, independent correlate of higher social functioning. Understanding the factors underlying driving behaviors in PLWH may contribute to interventions to promote better mobility and improved access to care.

Use of digital health technologies to examine subjective and objective sleep with next-day cognition and daily indicators of health in persons with and without HIV

Most previous studies investigating sleep's association with health outcomes have relied on averaged sleep quality and laboratory-based health measures. This study examines the dynamic within-person relationships between subjective (Ecological Momentary Assessment) and objective sleep (actigraphy) on next-day cognition (subjective and objective), mood, and engagement in daily activities using linear mixed-effects regression modeling. Participants included 94 individuals (59 people with HIV, 35 HIV-) aged 50-74, assessed daily for 14 consecutive days/nights. Subjective and objective sleep were well correlated and were both associated with subjective ratings of cognition, but not objective cognition. Worse subjective sleep was associated with next-day lower happiness and higher depressed mood, and more pain, but was not related to next-day daily activities. Objective sleep was associated with next-day depressed mood and feelings of worry, and was positively associated with next-day television watching. Results provide evidence to support the utility of real-time assessment for sleep and functional outcomes that may lead to potential personalized interventions for individuals with and without HIV.

Mitochondrial DNA haplogroups and domain-specific neurocognitive performance in adults with HIV

Neurocognitive (NC) impairment (NCI) is an important cause of morbidity in persons with HIV (PWH). In the high-energy environment of the central nervous system, mitochondria contribute to neuroinflammation and aging, which may ultimately drive the pathogenesis of neurodegenerative diseases. Mitochondrial DNA (mtDNA) haplogroups are associated with health outcomes in PWH. For example, we previously observed less global NCI in Hispanic ancestry PWH having mtDNA haplogroup B. Another study reported increased NCI among PWH having African subhaplogroup L2a. We therefore analyzed NC domains in relation to these haplogroups in CNS HIV Antiretroviral Therapy Effects Research (CHARTER), a multi-site observational neuro-HIV study. Haplogroups were assigned using mtDNA sequence in 1016 PWH. Outcomes were NCI, defined by domain deficit score and mean T-scores (TS) for seven NC domains. Ancestry-stratified analyses of NC performance included Wilcoxon rank sum, χ2, and Fisher's exact tests. Multivariable regression adjusted for NC comorbidity, antiretroviral therapy use, and nadir CD4+ T cells. Among 98 Hispanic ancestry PWH, executive function, learning, and recall performance were better with haplogroup B (N = 17) than other haplogroups. With adjustment for covariates, haplogroup B remained associated with better executive function (p = 0.04) and recall TS (p = 0.03). PWH with haplogroup B had fewer impaired domains than other haplogroups (p < 0.01). Subhaplogroup L2a (N = 89) was associated with greater NCI in learning, recall, and working memory among 478 PWH of African ancestry, and had more impaired domains than other subhaplogroups (p < 0.01). These findings may inform risk stratification for NCI and studies to define mechanisms by which mtDNA variation may influence NCI in PWH.

Psychometric utility of the international HIV dementia scale and Montreal Cognitive Assessment in HIV-associated asymptomatic neurocognitive impairment

There is a growing need for brief screening measures for HIV Associated Neurocognitive Disorders (HAND). We compared two commonly used measures (the Montreal Cognitive Assessment [MoCA] and the International HIV Dementia Scale [IHDS]) in their ability to identify asymptomatic HAND (i.e., asymptomatic neurocognitive impairment [ANI]). Participants included 74 Thai PLWH: 38 met Frascati criteria for ANI and 36 were cognitively normal (CN). Participants completed Thai language versions of the MoCA (MoCA-T) and IHDS, and a validated neurocognitive battery. We examined between-group differences for MoCA-T and IHDS total scores, and scale subcomponents. We also conducted receiver operating characteristic (ROC) analyses to determine the ability of the MoCA-T and IHDS to discriminate between CN and ANI groups, and compared their area under the curve (AUC) values. Results revealed lower MoCA-T total score, as well as the Visuospatial/Executive and Delayed Recall subtask scores, in the ANI relative to CN group. Groups did not differ on the IHDS. For ROC analyses, the MoCA-T, but not the IHDS, significantly differentiated the ANI from CN group, and there was a significant difference in AUC values between the MoCA-T (AUC = .71) and IHDS (AUC = .56). Sensitivity and specificity statistics were poor for both screening measures. These data indicate while the MoCA-T functions better than the IHDS in detecting Thai PLWH with ANI, the mildest form of HAND, neither cognitive screener, showed strong utility. Our findings reflect the limited efficacy of common screening measures in detecting subtler cognitive deficits among Thai PLWH, and highlight the need for better screening tools.

Improvement of HIV-associated neurocognitive disorders after antiretroviral therapy intensification: the Neuro+3 study

OBJECTIVES

Despite the effectiveness of antiretroviral (ARV) therapy to control HIV infection, HIV-associated neurocognitive disorders (HAND) remain frequent. The Neuro+3 study assessed the cognitive improvement associated with ARV intensification based on increased CNS penetration effectiveness (CPE) scoring ≥+3 and total CPE score ≥9.

METHODS

Thirty-one patients, aged 18-65 years, with confirmed diagnosis of HAND and effective ARV therapy were included. The cognitive improvement was measured using Frascati three-stage classification and global deficit score (GDS) after 48 and 96 weeks of ARV intensification. Ultrasensitive HIV-RNA, neopterin, soluble CD14, CCL2, CXCL10, IL6, IL8 and NF-L were measured in plasma and cerebrospinal fluid at Day 0 (baseline), Week 48 (W48) and W96.

RESULTS

The intensified ARV was associated with a median (IQR) CPE score increase from 6 (4-7) at baseline to 10 (9-11). From baseline to W96, the median (IQR) GDS decreased from 1.4 (0.8-2.2) to 1.0 (0.6-2.0) (P = 0.009); HAND classification improved from 2 to 1 HIV-associated dementia, 22 to 8 mild neurocognitive disorders, 7 to 17 asymptomatic neurocognitive impairment and 0 to 5 patients without any neurocognitive alterations (P = 0.001). In multivariable linear regression analysis, GDS improvement at W96 was significantly associated with CPE score ≥9 after intensification (P = 0.014), CD4 lymphocyte increase at W48 (P < 0.001) and plasma CXCL10 decrease at W96 (P = 0.001).

CONCLUSIONS

In patients with HAND, a significant cognitive improvement was observed after the ARV intensification strategy, with a higher CPE score. Cognitive improvement was more often observed in the case of a switch of two drug classes, arguing for better control of CNS HIV immune activation.

Higher CSF Ferritin Heavy-Chain (Fth1) and Transferrin Predict Better Neurocognitive Performance in People with HIV

HIV-associated neurocognitive disorder (HAND) remains prevalent despite antiretroviral therapy and involves white matter damage in the brain. Although iron is essential for myelination and myelin maintenance/repair, its role in HAND is largely unexplored. We tested the hypotheses that cerebrospinal fluid (CSF) heavy-chain ferritin (Fth1) and transferrin, proteins integral to iron delivery and myelination, are associated with neurocognitive performance in people with HIV (PWH). Fth1, transferrin, and the pro-inflammatory cytokines TNF-α and IL-6 were quantified in CSF at baseline (entry) in 403 PWH from a prospective observational study who underwent serial, comprehensive neurocognitive assessments. Associations of Fth1 and transferrin with Global Deficit Score (GDS)-defined neurocognitive performance at baseline and 30-42 months of follow-up were evaluated by multivariable regression. While not associated with neurocognitive performance at baseline, higher baseline CSF Fth1 predicted significantly better neurocognitive performance over 30 months in all PWH (p < 0.05), in PWH aged < 50 at 30, 36, and 42 months (all p < 0.05), and in virally suppressed PWH at all three visit time-points (all p < 0.01). Higher CSF transferrin was associated with superior neurocognitive performance at all visits, primarily in viremic individuals (all p < 0.05). All associations persisted after adjustment for neuro-inflammation. In summary, higher CSF Fth1 is neuroprotective over prolonged follow-up in all and virally suppressed PWH, while higher CSF transferrin may be most neuroprotective during viremia. We speculate that higher CSF levels of these critical iron-delivery proteins support improved myelination and consequently, neurocognitive performance in PWH, providing a rationale for investigating their role in interventions to prevent and/or treat HAND.

Depression is associated with hippocampal volume loss in adults with HIV

Depressive symptoms are more prevalent in persons with HIV (PWH) than HIV‐uninfected individuals. In HIV‐uninfected individuals, depression has been associated with atrophy in the hippocampus and other brain regions. In the present study, we investigated the impact of depression on brain structure in PWH. One hundred PWH participated in a cross‐sectional study (56.6 ± 6.4 yrs, range 41–70 yrs, 24 females, 63 African Americans). The Beck's Depression Inventory‐II (BDI‐II) was used to assess depressive symptoms. Structural MRI images were collected. Both the voxel‐based morphometry (VBM) technique and a region of interest (ROI) based approach were used to examine the relationship between hippocampal gray matter volume (GMv) and depressive symptoms. The impact of HIV CD4 nadir and antidepressants was also investigated. Both VBM and ROI approaches revealed that higher BDI‐II scores (implicating more severe depressive symptoms) were associated with loss of hippocampal GMv, especially in the right hippocampus and the right entorhinal cortex. Low CD4 nadir predicted additional hippocampal volume loss independent of depressive symptoms. Taking antidepressants did not have a detectable effect on hippocampal volume. In summary, having more depressive symptoms is associated with smaller hippocampal volume in PWH, and a history of severe immunosuppression (i.e., low CD4 nadir) correlates with additional hippocampal volume reduction. However, the impact of depression on hippocampal volume may be independent of HIV‐disease severity such as low CD4 nadir.

Connectome-based prediction of global cognitive performance in people with HIV

•

Networks strengths predicted global cognitive performance in PWH.

•

Model generalized to data from an independent PWH sample.

•

Network strengths in PWH with HAND were different from either controls or PWH without HAND.

•

Network strengths may serve as a potential biomarker to assist HAND diagnosis.

Global cognitive performance plays an important role in the diagnosis of HIV-associated neurocognitive disorders (HAND), yet to date, there is no simple way to measure global cognitive performance in people with HIV (PWH). Here, we performed connectome-based predictive modeling (CPM) to pursue a neural biomarker of global cognitive performance in PWH based on whole-brain resting-state functional connectivity. We built a CPM model that successfully predicted individual differences in global cognitive performance in the training set of 67 PWH by using leave-one-out cross-validation. This model generalized to both 33 novel PWH in the testing set and a subset of 39 PWH who completed a follow-up visit two years later. Furthermore, network strengths identified by the CPM model were significantly different between PWH with HAND and without HAND. Together, these results demonstrate that whole-brain functional network strengths could serve as a potential neural biomarker of global cognitive performance in PWH.

Telomere length is associated with HIV infection, methamphetamine use, inflammation, and comorbid disease risk

BACKGROUND

HIV infection and methamphetamine dependence (METH) are each associated with inflammation and premature aging, but their impact on biological aging is difficult to measure. Here we examined the impact of HIV and METH on leukocyte telomere lengths (LTL), and the correlations between LTL and other aging biomarkers.

METHODS

The study was a cross-sectional analysis of 161 individuals categorized by HIV and methamphetamine (METH) dependence status into four groups: HIV-METH- (n = 50), HIV-METH+ (n = 29), HIV + METH- (n = 40), and HIV + METH+ (n = 42). We analyzed the relationships of leukocyte telomere length (telomere to single copy gene [T/S] ratio) with demographic and clinical data as well as a panel of biomarkers of inflammation and endothelial activation measured in blood and cerebrospinal fluid (CSF).

RESULTS

HIV and METH were independently associated with shorter T/S ratio, even after adjusting for demographics and leukocyte count (R2 = 0·59, p < 0·0001). Higher plasma C-reactive protein (p = 0·0036) and CSF VCAM-1 (p = 0·0080) were also associated with shorter T/S ratio. A shorter T/S ratio was associated with higher risk for cardiovascular disease (p < 0·0001) and stroke (p < 0·0001), worse motor functioning (p = 0·037) and processing speed (p = 0·023), more depressive symptoms (p = 0·013), and higher CSF neurofilament-light (p = 0·003).

CONCLUSIONS

HIV and METH dependence were each associated with shorter telomeres. After adjusting for demographics, HIV, and METH, T/S ratio remained associated with aging-related outcomes including neurocognitive impairment, neurodegeneration, risks of cardiovascular disease and stroke. While not establishing causality, this study supports using the T/S ratio as a biomarker for estimating the impact of HIV and comorbidities on long-term health.

Low CD4+ cell count nadir exacerbates the impacts of APOE ε4 on functional connectivity and memory in adults with HIV

OBJECTIVE

Nearly half of individuals living with HIV in the USA are now 50 or older. This rapidly ageing populace may be at an increasingly greater risk of Alzheimer's disease. However, the potential interaction between HIV-disease and Alzheimer's disease pathogenesis (i.e. Alzheimer's disease genetic risk factors) on brain function remains an open question. The present study aimed to investigate the impact of APOE ε4 on brain function in middle-aged to older people with HIV (PWH), as well as the putative interaction between ε4 and HIV disease severity.

METHODS

Ninety-nine PWH participated in a cross-sectional study (56.3 ± 6.5 years, range 41-70 years, 27 women, 26 ε4 carriers and 73 noncarriers). Structural MRI and resting-state functional MRI were collected to assess alterations in brain structure and functional connectivity, respectively.

RESULTS

APOE ε4 was associated with worse memory performance and reduced functional connectivity in the memory network. The functional connectivity reduction was centred at the caudate nucleus rather than hippocampus and correlated with worse memory performance. In ε4 carriers, low CD4+ cell count nadir was associated with reduced functional connectivity in the memory network, but this association was absent in noncarriers. Furthermore, there was an indirect detrimental impact of ε4 on memory performance through memory network functional connectivity. However, this indirect effect was contingent on CD4+ cell count nadir, that is the indirect effect of ε4 on memory was only significant when CD4+ cell count nadir was low.

INTERPRETATION

APOE ε4 is associated with reduced memory and reduced functional connectivity within the memory network, and low CD4+ cell count nadir -- indicating a history of severe immunosuppression -- may exacerbate the effects of ε4.

Neurocognitive impairment and health-related quality of life among people living with Human Immunodeficiency Virus (HIV)

The association between HIV-associated neurocognitive impairment (NCI) and health-related quality of life (HRQoL) is not well known. We investigated this association among the CNS (Central Nervous System) HIV Antiretroviral Therapy Effects Research (CHARTER) study participants. We performed factor analysis to distinguish physical and mental HRQoL, followed by general linear models. We analyzed 1,340 HIV participants, including 35.6% with NCI, 77.2% males, 70.5% unemployed, and 42.2% with depression. Impaired participants had lower (worse) mental and physical HRQoL mean scores compared to unimpaired participants. NCI was negatively associated with mental HRQoL in crude (mean difference: -4.38; 95% CI: -6.70 to -2.06) and adjusted analysis (-2.56, -4.83 to -0.30). NCI was also negatively associated with physical HRQoL in unadjusted analysis (-4.62, -7.45 to -1.78), though the association weakened in the adjusted analysis (-2.20, -4.81 to 0.40). The association between NCI and HRQoL was confounded mainly by employment and was partially mediated by depression. These findings suggest that future strategies aimed at improving HRQoL among HIV-infected patients with NCI might benefit from concurrent management of depression.

Validation of the mobile verbal learning test: Illustration of its use for age and disease-related cognitive deficits

OBJECTIVE

We developed a mobile cognitive test of verbal learning and memory, the mobile verbal learning test (mVLT), to allow for brief, repeated and portable delivery of a 12-item list learning test through a smartphone. This study examined the psychometric properties of the mVLT among older persons with and without human immunodeficiency virus (HIV).

METHODS

Sixty-eight persons with HIV and 36 HIV-negative individuals (aged 50-74) completed three trials of the mVLT on a smartphone once daily for 14 days. A different word list was administered each day.

RESULTS

Participants completed 80% of the 14 mVLT administrations, equating to 1166 valid and complete mVLTs. Neither adherence nor mean mVLT total score (number correct in 3 recall trials) differed by HIV status. No practice effects from repeated mVLT administration were observed, and there were moderately strong correlations of mVLT performance with performance on the in-lab version of the task and with traditional cognitive assessments of cognitive processes contributing to memory. We found evidence of within-person learning across mVLT trials, with persons with HIV demonstrating less learning from trials 1 to 3 compared to HIV-negative participants.

CONCLUSIONS

The mVLT is a valid method to assess learning in the real world in older adults with and without HIV.

Metabolic Risk Factors as Differential Predictors of Profiles of Neurocognitive Impairment Among Older HIV+ and HIV- Adults: An Observational Study

OBJECTIVE

Neurocognitive performance among older persons, including those living with HIV (people living with HIV [PLWH]), exhibits significant heterogeneity, suggesting subpopulations with differing profiles of neurocognitive impairment (NCI). Metabolic factors are associated with NCI, but their relationships to cluster-derived NCI profiles are unknown.

METHOD

Participants (144 PLWH and 102 HIV uninfected) aged 50+ years completed a neuropsychological battery assessing seven cognitive domains. Latent class analysis (LCA) identified NCI profiles separately by HIV serostatus and in a combined sample. Obtained classes were examined against the Montreal Cognitive Assessment (MoCA) and diagnoses of HIV-associated neurocognitive disorders (HAND). Multinomial regression identified metabolic predictors of classification.

RESULTS

LCA identified three latent classes in each participant sample: Class1Multidomain NCI (high probability of impairment across multiple domains), Class 2Learning & Recall NCI (high probability of impairment in learning and recall), and Class 3NC Unimpaired (low probability of NCI across all domains). Severity of NCI implied by classes corresponded with MoCA scores and HAND diagnoses. In analyses on the combined sample, compared to HIV-uninfected individuals, PLWH were more likely to be in Class1Multidomain NCI. Among PLWH, those with dyslipidemia and hypertension had greater odds of classification in Class 1Multidomain NCI while those with central obesity had higher odds of classification in Class 2Learning & Recall NCI; metabolic syndrome approached significance as a differential predictor. Regardless of HIV status, individuals with diabetes were more likely to be in Class 1Multidomain NCI.

CONCLUSIONS

Metabolic risk factors confer heightened risk of NCI in HIV infection. Interventions to reduce metabolic risk may improve neurocognitive outcomes among PLWH.

The Impact of Antiretroviral Therapy on Neurocognitive Outcomes Among People Living with HIV in Low- and Middle-Income Countries (LMICs): A Systematic Review

Low and middle-income countries (LMICs) are the epicenter of the HIV epidemic. The scale-up of antiretroviral therapy (ART) has reduced mortality, but HIV-associated neurocognitive impairment (HANI) remains prevalent, which impacts functional performance, medication adherence, and quality of life. We aimed to evaluate the effect of ART on neurocognitive outcomes among people living with HIV/AIDS in LMICs and to identify determinants of these outcomes. We searched electronic databases and reference lists for studies published between 1996 and 2019. Two reviewers screened the primary studies for inclusion and performed the critical appraisal. Results were synthesized using the 'Synthesis without meta-analysis' approach through simple vote counting. We identified 31 studies conducted across four regions (Africa, Asia, South America, and Eastern Europe). Nine studies were cross-sectional, 15 were prospective, and seven were randomized controlled trials. The majority of the articles showed improved neurocognitive performance with ART use but found no association with treatment duration, regimen, central penetrating effectiveness, and conventional biomarkers. Despite the lack of appropriate norms and not accounting for practice effect in most studies, the evidence suggests ART is useful in the treatment of HIV-associated neurocognitive impairment (HANI) but limited in addressing legacy effects, and peripheral, and central viral reservoirs. Improved early ART treatment programs, viral reservoir eradication strategies, and identification of novel biomarkers will be critical in efforts to minimize HIV-associated neurocognitive impairment. PROSPERO registration: CRD42020152908.

Altered Gray Matter Volume and Functional Connectivity in Human Immunodeficiency Virus-Infected Adults

People living with human immunodeficiency virus (HIV) (PLWH) are at high risk of neurocognitive impairment. The pathogenesis of neurocognitive impairment remains unclear, and there is still no diagnostic biomarker. By coupling three-dimensional T1-weighted imaging and resting-state functional imaging, we explored structural and functional alterations in PLWH and examined whether such imaging alterations had the potential to denote neurocognitive function. A total of 98 PLWH and 47 seronegative controls aged 20–53 years were recruited. Structural alterations were first explored between HIV-negative controls and PLWH. Subsequently, brain regions showing gray matter alterations were used as seeds for separate whole-brain functional connectivity (FC) analysis. Finally, the relationships between imaging alterations and cognitive function were explored. PLWH suffered from thalamus, occipital lobe, and hippocampus/parahippocampus atrophy. Visual cortices in PLWH showed decreased anticorrelation with the posterior cingulate cortex and left angular gyrus of the default mode network. FC within the visual cortices (between the left calcarine and right calcarine) and in the thalamic prefrontal circuit and between the thalamus and somatosensory association cortex were also altered. In addition, FC between the left thalamus and right dorsolateral prefrontal cortex in the cognitively impaired group was significantly different from that in the cognitively normal group in PLWH. Partial correlation analysis uncorrected for multiple comparisons suggested that some imaging alterations can be associated with neurocognition. Our study supports the presence of brain atrophy and functional reconfiguration in PLWH. Imaging alterations can be associated with neurocognitive function. We hold that neuroimaging is a promising approach in evaluating PLWH and might have the potential to clarify the pathogenesis of HIV-associated neurocognitive disorder.

Reactions to a Probable Diagnosis of HIV-Associated Neurocognitive Disorder: A Content Analysis

Half of the people living with HIV have cognitive deficits indicative of HIV-associated neurocognitive disorders (HANDs). With few treatment options, informing patients about a HAND diagnosis is a questionable practice. A sample of 139 people living with HIV were administered gold-standard cognitive tests; scores were used to determine whether they met cognitive criteria for HAND. Participants were informed that they met the criteria for HAND and asked 2 open-ended questions about their reactions to learning this information. Participant responses were recorded verbatim and coded into 3 overarching themes: positive, indifferent, and negative. Positive responses contained subthemes of confirmation, gratitude, desire for improvement, and curiosity. Indifferent responses contained nonreactive responses, apathy, and confusion. Negative responses contained surprise, discontentment, fear, and denial. Although most participants responded positively to feedback about HANDs, others experienced distress. Nurse clinicians should be mindful about informing patients if they have HAND while also educating them about brain health.

Cerebrovascular Disease in Children Perinatally Infected With Human Immunodeficiency Virus in Zambia

BACKGROUND

High rates of cerebrovascular disease (CVD) have previously been described in pediatric human immunodeficiency virus (HIV). However, little is known about pediatric CVD in the era of antiretroviral therapy or about the contribution of CVD to HIV-associated neurocognitive disorders.

METHODS

We completed a neuroimaging substudy of the HIV-Associated Neurocognitive Disorders in Zambia study, a prospective cohort study of neurocognitive complications of pediatric HIV. Brain magnetic resonance imaging (1.5 T) was acquired for 34 HIV+ children on antiretroviral therapy and 17 HIV-exposed uninfected children (aged eight to 17 years). Demographics, medical history, neurological examination, and neuropsychologic testing results were collected. Two neuroradiologists, unaware of HIV status and clinical course, read the scans.

RESULTS

CVD was identified in seven of 34 children with HIV (HIV+ CVD+) and no HIV-exposed uninfected children (21% vs 0%, P = 0.05). Three participants had white matter changes suggestive of small vessel disease, four had infarcts, and two had evidence of intracranial artery stenosis. Age of antiretroviral therapy initiation and exposure to protease inhibitors or efavirenz was not significantly different between children with and without CVD. HIV+ CVD+ children had significantly worse scores on a summary measure of cognition than the HIV+ CVD- group (NPZ8 score -0.57 vs 0.33, P = 0.04).

CONCLUSIONS

This study demonstrates high rates of CVD in children with HIV despite antiretroviral therapy, and worse cognitive performance in children with CVD. Longitudinal studies are necessary to determine the mechanisms and incidence of new-onset CVD in children with HIV.

Lifetime Methamphetamine Use Disorder and Reported Sleep Quality in Adults Living with HIV

This study evaluated whether a history of lifetime methamphetamine (MA) use disorder increases risk for poor sleep quality in people with or without HIV infection (HIV+/HIV-). Participants (n = 313) were stratified into four groups based on HIV status and lifetime MA use disorder diagnosis [HIV+/MA+ (n = 84); HIV+/MA- (n = 141); HIV-/MA+ (n = 16); and HIV-/MA- (n = 72)] and compared on global sleep outcomes using the Pittsburgh Sleep Quality Index (PSQI). Significant differences on global sleep were observed between HIV+/MA+ and HIV+/MA- groups, but not between the HIV- groups. Follow-up multiple regression analyses within the HIV+ subgroups examined global sleep scores as a function of MA status and clinical covariates, including those related to HIV disease and demographics. HIV+ individuals with a history of MA use disorder evidenced significantly poorer sleep quality and were more likely to be classified as problematic sleepers than those without a lifetime disorder. This was independent of depressed mood, body mass index, and viral suppression while on treatment. Poorer reported sleep quality among HIV+/MA+ was associated also with multiple adverse functional outcomes, including greater objective cognitive impairment, unemployment, clinical ratings of functional impairment, and self-reported cognitive difficulties, decreased independence in activities of daily living, and poorer overall life quality. Interventions to avoid or curtail MA use in HIV+ individuals may help protect sleep quality and improve functioning.

Lower CSF homovanillic acid relates to higher burden of neuroinflammation and depression in people with HIV disease

BACKGROUND

HIV-related neuroinflammation has been proposed as a catalyst for dopaminergic dysregulation in mesocortical pathways, which may contribute to the pathogenesis of depression. Abnormalities in dopaminergic neurotransmission and depression are common in people with HIV (PWH), however the link between dopamine (DA) and depression in PWH is poorly characterized. This study investigated CSF dopaminergic biomarkers, specifically DA and its metabolite, homovanillic acid (HVA), and examined their relationship with depressive symptoms and CSF neuroinflammatory markers in PWH and HIV-seronegative (HIV-) individuals.

METHODS

Participants were 102 HIV- individuals and 123 PWH (mean age = 42) who underwent neuropsychiatric evaluations and lumbar puncture. Current depression severity was classified using the Beck Depression Inventory-II (BDI-II). CSF was assayed for DA and HVA using high performance liquid chromatography and neuroinflammatory markers using immunoassays. Linear regressions modelled BDI-II scores as a function of HIV, dopaminergic biomarker z-scores, and their interaction, controlling for psychosocial factors. Correlational analyses examined dopaminergic and neuroinflammatory relationships.

RESULTS

PWH had significantly higher BDI-II scores than HIV- participants. DA and HVA were not associated with HIV status but both significantly moderated the effect of HIV on BDI-II scores, such that PWH exhibited higher depressive symptoms than HIV- participants only at lower concentrations of HVA (z ≤ 0.06) and DA (z ≤ 0.11). In PWH only, lower HVA significantly correlated with higher BDI-II scores and higher neuroinflammation, including higher MCP-1 and IP-10.

CONCLUSIONS

Results suggest that the pathophysiology of depression in PWH differs from that in HIV- individuals. Specifically, lower central dopaminergic activity was selectively associated with greater depressive symptoms and neuroinflammation in PWH. With the rise in consideration of DA agonists for the treatment of depression, these results suggest that PWH may show a greater response to these agents than their HIV- peers.

Older HIV+ and HIV- Adults Provide Similar Definitions of Successful Aging: A Mixed-Methods Examination

BACKGROUND AND OBJECTIVE

As HIV-infected (HIV+) individuals age, there is a need to understand successful aging (SA) from the patient perspective. This study compared SA definitions between HIV+ and HIV-uninfected (HIV-) older adults and then examined correlates of SA categories.

RESEARCH DESIGN AND METHODS

Ninety-three HIV+ and 46 HIV- older (aged 50+) adults provided brief definitions of SA, which was examined using content analysis. We then compared the frequency of SA categories by serostatus and examined the correlates of SA categories within both groups.

RESULTS

Seven SA categories emerged: General Health, Cognitive Health & Ability, Physical/Biological Health & Ability, Social Relationships, Attitudes, Psychological, & Emotional Well-Being, Proactive & Engaged Lifestyle, and Independence. While no significant differences emerged, HIV- older adults were more likely to report General Health and the subcategory of Longevity/Survival, while HIV+ older adults were more likely to report subcategories of Enjoying Life & Fulfillment and Maintaining Balance. Few demographic correlates of SA categories emerged. Mood and HIV characteristics were not associated with SA categories. In both groups, those without neurocognitive impairment were significantly more likely to endorse General Health than those with neurocognitive impairment.

DISCUSSION AND IMPLICATIONS

HIV+ and HIV- older individuals may generally perceive SA similarly, and their definitions parallel with existing models of SA. Yet, living with a chronic illness may cause HIV+ older adults to place greater value on quality of life and life satisfaction than physical health and chronological age. Observational and intervention studies may use similar approaches in evaluating and maximizing SA.

Assessing Cognitive Functioning in People Living With HIV (PLWH): Factor Analytic Results From CHARTER and NNTC Cohorts

BACKGROUND

Single summary scores, such as the Global Deficit Score, are often used to classify overall performance on neuropsychological batteries. The factor structure of test scores that underlie Global Deficit Score in studies of people living with HIV (PLWH) was assessed to determine whether individual test scores loaded onto a unitary factor to summarize performance.

SETTING

Secondary data analysis on baseline data of PLWH from National NeuroAIDS Tissue Consortium and CNS HIV Antiretroviral Therapy Effects Research (CHARTER) Study.

METHOD

Primary analyses included testing model structure and fit of neuropsychological test scores with confirmatory and exploratory factor analyses. Secondary analyses involved receiver operating characteristic curves, and associations with psychosocial and medical variables.

RESULTS

Participants with confounds were excluded, leading to 798 (National NeuroAIDS Tissue Consortium) and 1222 (CHARTER) cases. When confirmatory factor analysis models were structured to be consistent with theoretically-based cognitive domains, models did not fit adequately. Per exploratory factor analyses, tests assessing speeded information processing, working memory, and executive functions loaded onto a single factor and explained the most variance in both cohorts. This factor tended to be associated with age, estimated premorbid ability, and aspects of substance use history. Its relation to age, in context of demographically corrected neuropsychological scores, suggested accelerated aging.

CONCLUSION

Results indicate that individual neuropsychological tests did not load exactly onto expected domains, suggesting another framework for future analyses of cognitive domains. The possibility of a new index, and its use to assess cognitive impairment in PLWH, is suggested for further diagnostic and prognostic purposes.

Global prevalence and burden of HIV-associated neurocognitive disorder

Objective

To characterize the prevalence and burden of HIV-associated neurocognitive disorder (HAND) and assess associated factors in the global population with HIV.

Methods

We searched PubMed and Embase for cross-sectional or cohort studies reporting the prevalence of HAND or its subtypes in HIV-infected adult populations from January 1, 1996, to May 15, 2020, without language restrictions. Two reviewers independently undertook the study selection, data extraction, and quality assessment. We estimated pooled prevalence of HAND by a random effects model and evaluated its overall burden worldwide.

Results

Of 5,588 records identified, we included 123 studies involving 35,513 participants from 32 countries. The overall prevalence of HAND was 42.6% (95% confidence interval [CI] 39.7–45.5) and did not differ with respect to diagnostic criteria used. The prevalence of asymptomatic neurocognitive impairment, mild neurocognitive disorder, and HIV-associated dementia were 23.5% (20.3–26.8), 13.3% (10.6–16.3), and 5.0% (3.5–6.8) according to the Frascati criteria, respectively. The prevalence of HAND was significantly associated with the level of CD4 nadir, with a prevalence of HAND higher in low CD4 nadir groups (mean/median CD4 nadir <200 45.2% [40.5–49.9]) vs the high CD4 nadir group (mean/median CD4 nadir ≥200 37.1% [32.7–41.7]). Worldwide, we estimated that there were roughly 16,145,400 (95% CI 15,046,300–17,244,500) cases of HAND in HIV-infected adults, with 72% in sub-Saharan Africa (11,571,200 cases, 95% CI 9,600,000–13,568,000).

Conclusions

Our findings suggest that people living with HIV have a high burden of HAND in the antiretroviral therapy (ART) era, especially in sub-Saharan Africa and Latin America. Earlier initiation of ART and sustained adherence to maintain a high-level CD4 cell count and prevent severe immunosuppression is likely to reduce the prevalence and severity of HAND.

The University of California San Diego performance-based skills assessment: a useful tool to detect mild everyday functioning difficulties in HIV-infected patients with very good immunological condition

Everyday functioning (EF) impairment is frequent in people living with HIV (PLWH). Our aim was to better explore EF and its association with PLWH cognition, by administering both the IADL scale, the most common functional scale, and a new and ecologic multi-domain (communication and financial skills) tool to measure EF as the University of California San Diego (UCSD) Performance-Based Skills Assessment-Brief Version (UPSA-B). Eighty-five PLWH on cART with very good immunological condition and 23 age- and education-matched healthy controls (HC) were enrolled. PLWH underwent a standardized neuropsychological battery plus IADL, and cognitive impairment was defined according to Frascati criteria. Both groups underwent the UPSA-B. Only 6 subjects (7%) were affected by cognitive impairment (asymptomatic profile). While IADL score was at ceiling for all patients, the UPSA-B total score was significantly worse in PLWH when compared with HC [mean 82.1 (SD 9.3) vs 89.2 (SD 6.2); p < 0.001]. At communication subtest, PLWH group and HC were significantly different (p = 0.002), while no difference emerged at financial skills (p = 0.096). Higher score at UPSA-B was independently associated with better global cognitive performance (composite Z-score) (β 7.79; p < 0.001). Also considering each single cognitive domain, UPSA-B performance (both total and at subtests) confirmed the association with neurocognitive performance. In conclusion, UPSA-B seems to better discriminate EF impairment than IADL in PLWH, and it was associated with cognitive functions, also in the absence of symptomatic cognitive impairment. Thus, it appears a promising tool in the context of HIV infection to avoid misdiagnosis and to better detect also mild EF.

Predictors of Intervention Adherence in Compensatory Cognitive Training for Veterans With a History of Mild Traumatic Brain Injury

OBJECTIVE

The purpose of this study was to determine modifiable predictors of intervention adherence in a study of group-based Compensatory Cognitive Training (CCT) for Iraq/Afghanistan War veterans with a history of mild traumatic brain injury (mTBI).

METHODS

One hundred twenty-three veterans enrolled in a randomized controlled trial of a 10-week CCT intervention (54 assigned to CCT) and were evaluated at baseline, 5 weeks, 10 weeks, and 15 weeks. CCT adherence was determined by the number of CCT sessions attended, with more sessions indicative of greater adherence. Baseline demographic and clinical characteristics, and subjective and objective neuropsychological performance, were examined in relation to CCT session attendance.

RESULTS

Older age and worse attention performance at baseline were associated with higher CCT attendance rates.

CONCLUSIONS

This study generates preliminary evidence for potential modifiable neuropsychological factors that may improve engagement in CCT interventions.

Cannabis Exposure is Associated With a Lower Likelihood of Neurocognitive Impairment in People Living With HIV

BACKGROUND

Aging and HIV have adverse effects on the central nervous system, including increased inflammation and neural injury and confer risk of neurocognitive impairment (NCI). Previous research suggests the nonacute neurocognitive effects of cannabis in the general population are adverse or null. However, in the context of aging and HIV, cannabis use may exert beneficial effects due to its anti-inflammatory properties. In the current study, we examined the independent and interactive effects of HIV and cannabis on NCI and the potential moderation of these effects by age.

METHODS

Participants included 679 people living with HIV (PLHIV) and 273 people living without HIV (HIV-) (18-79 years old) who completed neurocognitive, neuromedical, and substance use assessments. NCI was defined as a demographically corrected global deficit score ≥ 0.5. Logistic regression models examined the effects of age, HIV, cannabis (history of cannabis substance use disorder and cannabis use in past year), and their 2-way and 3-way interactions on NCI.

RESULTS

In logistic regression models, only a significant interaction of HIV X cannabis was detected (P = 0.02). Among PLHIV, cannabis was associated with a lower proportion of NCI (odds ratio = 0.53, 95% confidence interval = 0.33-0.85) but not among HIV- individuals (P = 0.40). These effects did not vary by age.

CONCLUSIONS

Findings suggest cannabis exposure is linked to a lower odds of NCI in the context of HIV. A possible mechanism of this result is the anti-inflammatory effect of cannabis, which may be particularly important for PLHIV. Further investigations are needed to refine the effects of dose, timing, and cannabis compound on this relationship, which could inform guidelines for cannabis use among populations vulnerable to cognitive decline.

Cognitive Rehabilitation and Exposure/Sorting Therapy for Late-Life Hoarding: Effects on Neuropsychological Performance

OBJECTIVES

Hoarding disorder (HD) is characterized by urges to save items, difficulty discarding possessions, and excessive clutter and has been associated with executive functioning deficits. A randomized controlled trial comparing Cognitive Rehabilitation and Exposure/Sorting Therapy (CREST) with a care management control condition demonstrated the efficacy of CREST in reducing hoarding symptoms in older adults. The purpose of the current study was to assess whether CREST may also lead to improved executive functioning.

METHOD

All participants were administered a neurocognitive battery at baseline and posttreatment. Linear mixed models with random intercepts were used to evaluate change in global neuropsychological functioning as well as change in individual executive functioning variables.

RESULTS

There was no significant group by time interaction for the Global Deficit score; however, there were significant group by time interactions on two of the executive functioning variables examined, such that participants in the CREST condition demonstrated significant improvement in cognitive flexibility and inhibition over time compared with the participants in the care management condition.

DISCUSSION

Our initial findings support the notion that CREST may be able to improve task switching, an important component of executive functioning, in older adults with HD.

HIV influences microtubule associated protein-2: potential marker of HIV-associated neurocognitive disorders

OBJECTIVE

Postmortem brains of patients diagnosed with HIV-1-associated neurocognitive disorders (HAND) exhibit loss of dendrites. However, the mechanisms by which synapses are damaged are not fully understood.

DESIGN

Dendrite length and remodeling occurs via microtubules, the dynamics of which are regulated by microtubule-binding proteins, including microtubule-associated protein 2 (MAP2). The HIV protein gp120 is neurotoxic and interferes with neuronal microtubules. We measured MAP2 concentrations in human cerebrospinal fluid (CSF) and MAP2 immunoreactivity in rat cortical neurons exposed to HIV and gp120.

METHODS

First, we examined whether HIV affects MAP2 levels by analyzing the CSF of 27 persons living with HIV (PLH) whose neurocognitive performance had been characterized. We then used rat cortical neurons to study the mechanisms of HIV-mediated dendritic loss.

RESULTS

PLH who had HAND had greater MAP2 concentrations within the CSF than cognitive normal PLH. In cortical neurons, the deleterious effect of HIV on MAP2-positive dendrites occurred through a gp120-mediated mechanism. The neurotoxic effect of HIV was blocked by a CCR5 antagonist and prevented by Helix-A, a peptide that displaces gp120 from binding to microtubules, conjugated to a nanolipoprotein particle delivery platform.

CONCLUSION

Our findings support that HIV at least partially effects its neurotoxicity via neuronal cytoskeleton modifications and provide evidence of a new therapeutic compound that could be used to prevent the HIV-associated neuropathology.

Successful Functional Aging in Middle-Aged and Older Adults with HIV

People living with HIV (PLWH) experience greater everyday functioning impairment. We examined frequency and correlates of successful functional aging (SFA) in PLWH. Using gold-standard questionnaires, SFA was defined in 174 HIV+ and 71 HIV- adults as absence of significant everyday cognitive symptoms and declines in instrumental activities of daily living. More HIV- (45%) than HIV+ (18%) adults met SFA criteria (p < 0.01). Depression, cognitive functioning, socioeconomic status, and HIV status were independent correlates of SFA (p values < 0.05). Motor ability, learning, and verbal fluency were associated with SFA. SFA was associated with health-related quality of life (HRQoL). PLWH are three times less likely to achieve SFA than HIV- adults, a phenotype that translates to HRQoL. While SFA is multifactorial, driven by clinico-demographic factors, HIV may pose additional risk to achieving SFA. Further work should examine other mechanisms whereby HIV hinders SFA (e.g., biomarkers, stress, mental health) and ultimately inform interventions to facilitate SFA.

Neurocognitive Impairment in the Combined Antiretroviral Therapy Era in a Romanian Cohort of Young Adults with Chronic HIV Infection

HIV-associated neurocognitive disorders (HAND) continue to be reported even in patients with successful antiretroviral treatment. We investigated the prevalence of neurocognitive impairment and possible HIV-associated determinants of cognition in a Romanian cohort of young adults, parenterally infected with HIV during their first years of life. Two hundred fourteen treatment-experienced HIV-positive individuals [median age: 24 years, males: 48%, median duration on combined antiretroviral therapy (cART): 12 years] underwent standard immunologic and virological monitoring and antiretroviral resistance testing using pol gene sequencing in both plasma and, when available, cerebrospinal fluid (CSF) paired samples. Neurocognitive impairment was assessed using a comprehensive neuropsychological test battery, and a global deficit score (GDS) was calculated (cutoff ≥0.5). Cognitive impairment was detected in 35% of the study participants, without any association with sex, median age, CD4 cell count (actual or nadir), CSF and plasma viral load (actual or zenith), AIDS diagnosis, duration of HIV infection, and cART characteristics. Participants carrying resistant viruses tended to be more frequently cognitively impaired (p = 0.36), with a higher median GDS value (p = 0.06) compared with participants harboring wild-type HIV, although the figures did not reach statistical significance. No signs of virological compartmentalization were observed based on CSF versus plasma viral load and on the profile of pol sequences. A moderate rate of mild neurocognitive impairment is still present in young adults with chronic HIV infection acquired in early childhood despite successful cART, without any association with classic markers of HIV infection. New biomarkers reflecting persistent central nervous system inflammation and neuronal injury may be more relevant for the development of HAND.

COMT Val158Met Polymorphism, Cardiometabolic Risk, and Nadir CD4 Synergistically Increase Risk of Neurocognitive Impairment in Men Living With HIV

OBJECTIVE

The Val allele of the Val158Met single-nucleotide polymorphism of the catechol-o-methyltransferase gene (COMT) results in faster metabolism and reduced bioavailability of dopamine (DA). Among persons living with HIV, Val carriers display neurocognitive deficits relative to Met carriers, presumably due to exacerbation of HIV-related depletion of DA. COMT may also impact neurocognition by modulating cardiometabolic function, which is often dysregulated among persons living with HIV. We examined the interaction of COMT, cardiometabolic risk, and nadir CD4 on neurocognitive impairment (NCI) among HIV+ men.

METHODS

Three hundred twenty-nine HIV+ men underwent COMT genotyping and neurocognitive and neuromedical assessments. Cohort-standardized z scores for body mass index, systolic blood pressure, glucose, triglycerides, and high-density lipoprotein cholesterol were averaged to derive a cardiometabolic risk score (CMRS). NCI was defined as demographically adjusted global deficit score of ≥0.5. Logistic regression modeled NCI as a function of COMT, CMRS, and their interaction, covarying for estimated premorbid function, race/ethnicity, and HIV-specific characteristics. Follow-up analysis included the 3-way interaction of COMT, CMRS, and nadir CD4.

RESULTS

Genotypes were 81 (24.6%) Met/Met, 147 (44.7%) Val/Met, and 101 (30.7%) Val/Val. COMT interacted with CMRS (P = 0.02) such that higher CMRS increased risk of NCI among Val/Val [odds ratio (OR) = 2.13, P < 0.01], but not Val/Met (OR = 0.93, P > 0.05) or Met/Met (OR = 0.92, P > 0.05) carriers. Among Val/Val, nadir CD4 moderated the effect of CMRS (P < 0.01) such that higher CMRS increased likelihood of NCI only when nadir CD4 <180.

DISCUSSION

Results suggest a tripartite model by which genetically driven low DA reserve, cardiometabolic dysfunction, and historical immunosuppression synergistically enhance risk of NCI among HIV+ men, possibly due to neuroinflammation and oxidative stress.

Double-blinded, placebo-controlled crossover trial to determine the effects of midodrine on blood pressure during cognitive testing in persons with SCI

Study Design:

Clinical trial.

Objectives:

Individuals with spinal cord injury (SCI) above T6 experience impaired descending cortical control of the autonomic nervous system which predisposes them to hypotension. However, treatment of hypotension is uncommon in the SCI population because there are few safe and effective pharmacological options available. The primary aim of this investigation was to test the efficacy of a single dose of midodrine (10 mg), compared to placebo, to increase and normalize systolic blood pressure (SBP) between 110–120 mmHg during cognitive testing in hypotensive individuals with SCI. Secondary aims were to determine the effects of midodrine on cerebral blood flow velocity (CBFv) and global cognitive function.

Setting:

United States clinical research laboratory.

Methods:

Forty-one healthy hypotensive individuals with chronic (≥ 1-year post-injury) SCI participated in this 2-day study.

Seated SBP, CBFv, cognitive performance were monitored before and after administration of identical encapsulated tablets, containing either midodrine or placebo.

Results:

Compared to placebo, midodrine increased SBP (4±13 vs. 18±24 mmHg, respectively; p<0.05); however, responses varied widely with midodrine (−15.7 to +68.6 mmHg). Further, the proportion of SBP recordings within the normotensive range did not improve during cognitive testing with midodrine compared to placebo. Although higher SBP was associated with higher CBFv (p=0.02), global cognitive function was not improved with midodrine.

Conclusions:

The findings indicate that midodrine increases SBP and may be beneficial in some hypotensive patients with SCI; however, large heterogeneity of responses to midodrine suggest careful monitoring of patients following administration.

Does the Key Task Measure Prospective Memory? Cautionary Findings from Parallel Studies in HIV Disease and Older Adults

OBJECTIVE

Despite its brevity and face validity, little is known about the construct validity of the naturalistic "Key Task" of prospective memory (PM), in which an examinee is instructed to remind the examiner at a designated time to retrieve keys (or another belonging) placed out of sight.

METHOD

Study 1 included 162 HIV+ and 52 HIV- comparison participants who completed the Key Task alongside well-validated measures of PM and a comprehensive neuropsychological battery that included everyday functioning measures. Study 2 used broadly parallel methods in 168 older community-dwelling Australians.

RESULTS

Overall, the Key Task was not reliably associated with neurocognitive functioning (including clinical and experimental measures of PM), PM symptoms, or everyday functioning in either sample.

CONCLUSIONS

The Key Task did not demonstrate compelling evidence of construct validity among persons living with HIV disease or older adults, which raises doubts regarding its clinical usefulness as a measure of PM.

Plasma Cystatin C Associates With HIV-Associated Neurocognitive Disorder but Is a Poor Diagnostic Marker in Antiretroviral Therapy-Treated Individuals

OBJECTIVE

To examine associations between plasma cystatin C and neurocognitive impairment (NCI) and its performance as a diagnostic marker before and during initial antiretroviral therapy (ART).

METHODS

Multivariable logistic regression and generalized estimating equations examined associations with NCI, determined by neuropsychological measurements, in participants of a 48-week randomized clinical trial of initial ART. Receiver operator characteristic curves examined diagnostic models of NCI.

RESULTS

Cystatin C was associated with NCI before ART [odds ratio (OR) 3.4 (95% CI: 1.2 to 9.4) for each 2-fold increase in baseline levels] and during 48 weeks of ART, in models that excluded baseline measurements [OR 3.0 (1.2 to 7.8) for each 2-fold increase in time-updated levels]. The strength of association increased with more severe impairment using HIV-associated neurocognitive disorder criteria [OR 2.2 (0.8 to 6.0) with asymptomatic NCI and OR 4.0 (1.5 to 11.0) with mild neurocognitive disorder or HIV-associated dementia vs. no impairment, for each 2-fold increase in time-updated levels] or by global development score [OR 2.6 (1.1 to 6.3) with mild impairment and OR 4.6 (1.1 to 18.9) with moderate or severe impairment vs. no impairment]. Cystatin C performed poorly as a diagnostic marker for NCI, however, with an area under the receiver operator characteristic curve of 0.58 at baseline and 0.54 at week 48.

CONCLUSIONS

Higher plasma cystatin C levels were significantly associated with NCI, but these levels did not seem to be useful as a diagnostic marker for this condition.

Tau Positron Emission Tomography Binding Is Not Elevated in HIV-Infected Individuals

Regional standardized uptake value ratios (SUVRs) for tau positron emission tomography (PET) were compared among 19 cognitively normal human immunodeficiency virus (HIV)-negative control individuals, 20 HIV-negative patients with symptomatic Alzheimer disease, 15 cognitively normal HIV-positive individuals, and 17 cognitively impaired HIV-positive individuals. Among the HIV-positive participants, the correlation between tau PET SUVRs and both HIV loads and CD4+ T-cell counts (recent and nadir). Tau PET SUVRs were similar for HIV-positive individuals and HIV-negative control individuals. Individuals with symptomatic Alzheimer disease had elevated tau PET SUVRs. Tau PET SUVRs did not correlate with impairment or clinical markers in HIV-positive participants. Older HIV-positive individuals are not at increased risk of tau-mediated neurodegeneration.

Clinical and Genetic Risk Prediction of Cognitive Impairment After Blood or Marrow Transplantation for Hematologic Malignancy

PURPOSE

Using a candidate gene approach, we tested the hypothesis that individual single nucleotide polymorphisms (SNPs) and gene-level variants are associated with cognitive impairment in patients with hematologic malignancies treated with blood or marrow transplantation (BMT) and that inclusion of these SNPs improves risk prediction beyond that offered by clinical and demographic characteristics.

PATIENTS AND METHODS

In the discovery cohort, BMT recipients underwent a standardized battery of neuropsychological tests pre-BMT and at 6 months, 1 year, 2 years, and 3 years post-BMT. Associations between 68 candidate genes and cognitive impairment were assessed using generalized estimating equation models. Elastic-Net regression was used to build Base (sociodemographic), Clinical, and Combined (Base plus Clinical plus genetic) risk prediction models of post-BMT impairment. An independent nonoverlapping cohort from the BMT Survivor Study with self-report of learning/memory problems (as identified by their health care provider) was used for model replication.

RESULTS

The discovery cohort included 277 participants (58.5% males; 68.6% non-Hispanic whites; and 46.6% allogeneic BMT recipients). Adjusting for BMT type, age at BMT, sex, race/ethnicity, and cognitive reserve, SNPs in the blood-brain barrier, telomere homeostasis, and DNA repair genes were significantly associated with cognitive impairment. Compared with the Clinical Model, the Combined Model had higher predictive power in both the discovery cohort (mean area under the receiver operating characteristic curve [AUC], 0.89; 95% CI, 0.85 to 0.93 v 0.77; 95% CI, 0.71 to 0.83; P = 1.24 × 10^-9) and the replication cohort (AUC, 0.71; 95% CI, 0.66 to 0.76 v 0.63; 95% CI, 0.57 to 0.68; P = .004).

CONCLUSION

Inclusion of candidate genetic variants enhanced the prediction of risk of post-BMT cognitive impairment beyond that offered by demographic/clinical characteristics and represents a step toward a personalized approach to managing patients at high risk for cognitive impairment after BMT.

Use of Neuroimaging to Inform Optimal Neurocognitive Criteria for Detecting HIV-Associated Brain Abnormalities

OBJECTIVE

Frascati international research criteria for HIV-associated neurocognitive disorders (HAND) are controversial; some investigators have argued that Frascati criteria are too liberal, resulting in a high false positive rate. Meyer et al. recommended more conservative revisions to HAND criteria, including exploring other commonly used methodologies for neurocognitive impairment (NCI) in HIV including the global deficit score (GDS). This study compares NCI classifications by Frascati, Meyer, and GDS methods, in relation to neuroimaging markers of brain integrity in HIV.

METHOD

Two hundred forty-one people living with HIV (PLWH) without current substance use disorder or severe (confounding) comorbid conditions underwent comprehensive neurocognitive testing and brain structural magnetic resonance imaging and magnetic resonance spectroscopy. Participants were classified using Frascati criteria versus Meyer criteria: concordant unimpaired [Frascati(Un)/Meyer(Un)], concordant impaired [Frascati(Imp)/Meyer(Imp)], or discordant [Frascati(Imp)/Meyer(Un)] which were impaired via Frascati criteria but unimpaired via Meyer criteria. To investigate the GDS versus Meyer criteria, the same groupings were utilized using GDS criteria instead of Frascati criteria.

RESULTS

When examining Frascati versus Meyer criteria, discordant Frascati(Imp)/Meyer(Un) individuals had less cortical gray matter, greater sulcal cerebrospinal fluid volume, and greater evidence of neuroinflammation (i.e., choline) than concordant Frascati(Un)/Meyer(Un) individuals. GDS versus Meyer comparisons indicated that discordant GDS(Imp)/Meyer(Un) individuals had less cortical gray matter and lower levels of energy metabolism (i.e., creatine) than concordant GDS(Un)/Meyer(Un) individuals. In both sets of analyses, the discordant group did not differ from the concordant impaired group on any neuroimaging measure.

CONCLUSIONS

The Meyer criteria failed to capture a substantial portion of PLWH with brain abnormalities. These findings support continued use of Frascati or GDS criteria to detect HIV-associated CNS dysfunction.

Multi-domain neurocognitive classification of primary brain tumor patients prior to radiotherapy on a prospective clinical trial

INTRODUCTION

We investigated multi-domain baseline neurocognition of primary brain tumor patients prior to radiotherapy (RT), including clinical predictors of function and association between pre-RT and post-RT impairment on a prospective trial.

METHODS

A multi-domain neuropsychological battery (memory, executive functioning, language, attention, processing) was performed on 37 patients, pre-RT and 3-(n = 21), 6-(n = 22) and 12-(n = 14) months post-RT. Impairment rate was the proportion of patients with standardized T-scores ≤ 1.5 standard deviations below normative means. Per-patient impairment across all domains was calculated using a global deficit score (GDS; higher value indicates more impairment). Associations between baseline GDS and clinical variables were tested. Global GDS impairment rate at each time point was the fraction of patients with GDS scores > 0.5.

RESULTS

Statistically significant baseline neurocognitive impairments were identified on 4 memory (all p ≤ 0.03) and 2 out of 3 (p = 0.01, p = 0.027) executive functioning tests. Per-patient baseline GDS was significantly associated with tumor volume (p = 0.048), tumor type (p = 0.043), seizure history (p = 0.007), and use of anti-epileptics (p = 0.009). The percentage of patients with the same impairment status at 3-, 6-, and 12-months as at baseline were 88%, 85%, and 85% respectively.

CONCLUSIONS

Memory and executive functioning impairment were the most common cognitive deficits prior to RT. Patients with larger tumors, more aggressive histology, and use of anti-epileptics had higher baseline GDS values. GDS is a promising tool to encompass multi-domain neurocognitive function, and baseline GDS can identify those at risk of cognitive impairment.

Brain Magnetic Resonance Imaging Findings Associated With Cognitive Impairment in Children and Adolescents With Human Immunodeficiency Virus in Zambia

BACKGROUND

Cognitive impairment is common in children and adolescents with human immunodeficiency virus (HIV). Brain magnetic resonance imaging (MRI) is a potentially useful tool to investigate the pathophysiology of HIV-associated cognitive impairment and may serve as a biomarker in future clinical trials. There are few published data on brain imaging in children with HIV in sub-Saharan Africa.

METHODS

Thirty-four perinatally infected subjects with HIV and age-matched HIV-exposed uninfected controls between the ages nine and 17 years were recruited from the Pediatric Center of Excellence in Lusaka, Zambia, as part of the HIV-associated Neurocognitive Disorders in Zambia study. Brain MRI sequences were acquired, and clinical and volumetric assessments were performed. Subjects underwent a comprehensive neuropsychologic battery, and cognitive impairment status was classified using a global deficit score approach. Regression models were used to evaluate relationships between MRI findings and cognitive function.

RESULTS

We identified cerebrovascular disease in seven of 34 subjects with HIV compared with zero of 17 controls (21% vs 0%, P = 0.04). We also identified decreased total brain volumes (1036 vs 1162 cm³, P = 0.03) and decreased cortical thickness in the right temporal lobes (3.12 vs 3.29 mm; P = 0.01) and right fusiform gyri (3.10 vs 3.25 mm; P = 0.02) of HIV-infected subjects with cognitive impairment.

CONCLUSIONS

These findings support the hypothesis that brain volumes may be useful biomarkers for cognitive outcomes in children with HIV. Further studies are necessary to investigate mechanisms of cerebrovascular disease and volume loss in children with HIV.

Low CD4 nadir linked to widespread cortical thinning in adults living with HIV

BACKGROUND

The history of immune suppression, especially CD4 nadir, has been shown to be a strong predictor of HIV-associated neurocognitive disorders (HAND). However, the potential mechanism of this association is not well understood.

METHODS

High resolution structural MRI images and neuropsychological data were obtained from fifty-nine HIV+ adults (mean age, 56.5 ± 5.8) to investigate the correlation between CD4 nadir and cortical thickness.

RESULTS

Low CD4 nadir was associated with widespread cortical thinning, especially in the frontal and temporal regions, and global mean cortical thickness correlated with CD4 nadir. In addition, worse global neurocognitive function was associated with bilateral frontal cortical thinning, and the association largely persisted (especially in the left frontal cortex) in the subset of participants who did not meet HAND criteria.

CONCLUSIONS

These results suggest that low CD4 nadir may be associated with widespread neural injury in the brain, especially in the frontal and temporal regions. The diffuse neural injury might contribute to the prevalence and the phenotypes of HAND, as well as the difficulty treating HAND due to a broad network of brain regions affected. Low CD4 nadir related neural injury to the frontal cortex might contribute to subtle neurocognitive impairment/decline, even in the absence of HAND diagnosis.

Peripheral Blood Mitochondrial DNA Copy Number Obtained From Genome-Wide Genotype Data Is Associated With Neurocognitive Impairment in Persons With Chronic HIV Infection

BACKGROUND

Mitochondrial DNA (mtDNA) copy number varies by cell type and energy demands. Blood mtDNA copy number has been associated with neurocognitive function in persons without HIV. Low mtDNA copy number may indicate disordered mtDNA replication; high copy number may reflect a response to mitochondrial dysfunction. We hypothesized that blood mtDNA copy number estimated from genome-wide genotyping data is related to neurocognitive impairment (NCI) in persons with HIV.

METHODS

In the CNS HIV Antiretroviral Therapy Effects Research (CHARTER) study, peripheral blood mtDNA copy number was obtained from genome-wide genotyping data as a ratio of mtDNA single-nucleotide polymorphism probe intensities relative to nuclear DNA single-nucleotide polymorphisms. In a multivariable regression model, associations between mtDNA copy number and demographics, blood cell counts, and HIV disease and treatment characteristics were tested. Associations of mtDNA copy number with the global deficit score (GDS), GDS-defined NCI (GDS ≥ 0.5), and HIV-associated neurocognitive disorder (HAND) diagnosis were tested by logistic regression, adjusting for potential confounders.

RESULTS

Among 1010 CHARTER participants, lower mtDNA copy number was associated with longer antiretroviral therapy duration (P < 0.001), but not with d-drug exposure (P = 0.85). mtDNA copy number was also associated with GDS (P = 0.007), GDS-defined NCI (P < 0.001), and HAND (P = 0.002). In all analyses, higher mtDNA copy number was associated with poorer cognitive performance.

CONCLUSIONS

Higher mtDNA copy number estimated from peripheral blood genotyping was associated with worse neurocognitive performance in adults with HIV. These results suggest a connection between peripheral blood mtDNA and NCI, and may represent increased mtDNA replication in response to mitochondrial dysfunction.

Plasma (1 → 3)-β-D-glucan and suPAR levels correlate with neurocognitive performance in people living with HIV on antiretroviral therapy: a CHARTER analysis

Despite antiretroviral therapy (ART), people living with HIV (PLWH) have higher rates of non-AIDS disorders, such as neurocognitive (NC) impairment (NCI) than the general population. (1-3)-β-D-Glucan (BDG) is a fungal cell wall component which serves as a biomarker for gut barrier integrity failure and microbial and fungal translocation. The primary objective of this study was to determine whether higher plasma and cerebrospinal fluid (CSF) levels of BDG and suPAR were associated with NCI in PLWH. Paired blood and CSF samples were collected cross-sectionally from 61 male adult PLWH on ART (95% virally suppressed) who underwent a detailed NC assessment as part of the prospective CHARTER study between 2005 and 2015. BDG and soluble urokinase plasminogen activator receptor (suPAR) were measured in frozen blood and CSF samples while soluble CD14 (sCD14), intestinal fatty acid binding protein (IFABP), and CD4/CD8 ratio were measured in blood only. Spearman's rho correlation analysis assessed associations between BDG, other biomarkers, and NC performance. Median BDG levels were 18 pg/mL in plasma (range 2-60 pg/mL) and 20 pg/mL in CSF (range 0-830 pg/mL). Higher levels of plasma BDG were associated with worse NC performance (Spearman's rho = - 0.32; p = 0.013) and with the presence of NCI (p = 0.027). A plasma BDG cutoff of > 30 pg/mL was 30% sensitive and 100% specific for NCI. After adjusting for age, higher plasma suPAR levels were also associated with worse NC performance (p < 0.01). No significant associations were observed between the remaining biomarkers and the NC variables. Plasma levels of BDG and age-adjusted suPAR may be new biomarkers for the detection of NCI in PLWH on suppressive ART.

Cross-sectional analysis of cognitive function using multivariate normative comparisons in men with HIV disease

BACKGROUND

Prevalence estimates of cognitive impairment in HIV disease vary widely. Here we used multivariate normative comparison (MNC) with identify individuals with impaired cognition, and to compare the results with those using the Frascati and Gisslén criteria.

METHODS

The current project used data collected before October 2014 from bisexual/gay men from the Multicenter AIDS Cohort Study. A total of 2904 men (mean age 39.7 years, 52.7% seropositive) had complete data in six cognitive domains at their first neuropsychological evaluation. T-scores were computed for each domain and the MNC was applied to detect impairment among seronegative and seropositive groups.

RESULTS

The MNC classified 6.26% of seronegative men as being impaired using a predetermined 5% false discovery rate. By contrast, the Frascati and the Gisslén criteria identified 24.54 and 11.36% of seronegative men as impaired. For seropositive men, the percentage impairment was 7.45, 25.73, and 11.69%, respectively, by the MNC, Frascati and Gisslén criteria. When we used seronegative men without medical comorbidities as the control group, the MNC, the Frascati and the Gisslén criteria identified 5.05, 27.07, and 4.21% of the seronegative men, and 4.34, 30.95, and 4.48% of the seropositive men as having cognitive impairment. For each method, serostatus was not associated with cognitive impairment.

CONCLUSION

The MNC controls the false discovery rate and therefore avoids the low specificity that characterizes the Frascati and Gisslén criteria. More research is needed to evaluate the sensitivity of the MNC method in a seropositive population that may be sicker and older than the current study sample and that includes women.

Considerations on nosology for HIV-associated neurocognitive disorders: it is time to update?

AIMS

The prognosis and the clinical manifestations of HIV infection have changed with the introduction of the potent combination antiretroviral therapy (cART); however, up to 50% of patients meet research criteria for "HIV-associated neurocognitive disorders" (HAND) according with current nosology. The majority of patients affected by HAND, especially in cohorts with suppressed plasma viremia, showed an Asymptomatic Neurocognitive Impairment (ANI), without any functional impairment. After more than 10 years from the introduction of the current so-called "Frascati criteria", this mini-review aimed to address the emerging limitations in current diagnosis procedures.

METHODS

We discussed the most relevant literature on HAND prevalence, etiology, and diagnosis.

RESULTS

We addressed three main emerging issues: (1) the unclear clinical relevance of ANI entity; (2) the evidences that Frascati criteria could produce a significant overestimation of HAND; (3) the need to better identify patients with a higher risk to develop HAND requiring routine neuropsychological examinations.

CONCLUSIONS

Frascati criteria should be updated to better respond to the present characteristics of HIV + cohorts and to help clinicians in their cognitive and global management.