Defining neurocognitive impairment in HIV: deficit scores versus clinical ratings

Distinct Effects of Selective Serotonin Reuptake Inhibitors and Serotonin-Norepinephrine Reuptake Inhibitors on Soluble Biomarkers in Blood and Cerebrospinal Fluid of People With HIV

BACKGROUND

Persistent inflammation affects people with HIV (PWH) despite antiretroviral therapy (ART). Selective serotonin and serotonin-norepinephrine reuptake inhibitors (SSRIs, SNRIs), HMG-CoA reductase-inhibitors (statins), and angiotensin-converting enzyme inhibitors (ACEIs) have immunomodulant properties. We evaluated the potential impact of these drugs on inflammation and neurodegeneration in PWH.

METHODS

Cross-sectional single-center (United States) analysis in 184 PWH on ART with plasma HIV RNA < 200 copies/mL. All participants had 10 biomarkers measured in blood and cerebrospinal fluid (CSF). To reduce dimensionality, hierarchical clustering and principal components (PCs) analysis were employed. The analyses were adjusted for duration of the drugs and clinical conditions.

RESULTS

Participants were mostly middle-aged men, with median CD4+ T cells of 620/µL. In adjusted models, SSRI use was associated with 3 PCs: higher CSF and plasma Aβ42 and CSF CCL2 (aβ=.14, P = .040); lower CSF 8-oxo-dG, total tau, and sCD14 (aβ=-.12, P = .042); and higher plasma sCD14 with lower sCD40L (aβ=.15, P = .042). SNRI use was associated with higher values of CSF and plasma neopterin and CSF sTNFR-II (aβ=.22, P = .004). Statins and ACEIs showed no association.

CONCLUSIONS

SSRIs and SNRIs had distinct biomarker signatures. SSRIs were associated with reduced neurodegeneration, immune activation, and oxidative stress in CSF, suggesting a role of SSRIs as adjunctive therapy in PWH.

Efficacy of Interventions to Improve Cognitive Function in Adults with Spinal Cord Injury: A Systematic Review

Cognitive impairment is a common complication following spinal cord injury (SCI) and imposes a significant negative impact on adjustment, functional independence, physical and mental health, and quality of life. It is unclear whether interventions for cognitive impairment following SCI are effective. A systematic review of controlled trials was performed to evaluate the effect of interventions on cognitive functions in adults with SCI using search engines: Embase, The Cochrane Library, MEDLINE, Scopus, CINAHL, and Web of Science up to December 2023. Two reviewers independently screened the articles, and study findings were synthesized and summarized. The risk of bias was evaluated using the Cochrane Risk of Bias 2.0 tool. Eight moderate-quality studies were found that investigated the effects of physical exercise/activity-based therapy plus cognitive training or intermittent hypoxia, diet modification and dietary supplements, tibial nerve or cortical stimulation, and drug therapy on cognitive function in SCI. Physical exercise/activity-based therapy plus cognitive training showed most promise for improving cognitive functions, while drug therapy, diet modification, and dietary supplements showed potential for improving cognitive function. However, about half of the participants experienced heightened instability in blood pressure following the administration of midodrine, and one participant reported gastrointestinal side effects after taking omega-3 fatty acids. There was no evidence of improvement in cognitive function for stimulation techniques. The current review highlights the scarcity of research investigating the effectiveness of interventions that target cognitive function after SCI. Further, the effects of these eight studies are uncertain due to concerns about the quality of designs and small sample sizes utilized in the trials, as well as the employment of insensitive neurocognitive tests when applied to adults with SCI. This review highlights a significant gap in knowledge related to SCI cognitive rehabilitation.

Associations Between Estimates of Arterial Stiffness and Cognitive Functioning in Adults With HIV

BACKGROUND

Vascular aging, a precursor of arterial stiffness, is associated with neurocognitive impairment (NCI) and cardiovascular disease. Although HIV is associated with rapid vascular aging, it is unknown whether arterial stiffness mediates changes in cognitive function. We explored whether estimated markers of vascular aging were associated with NCI indices in HIV-positive individuals.

METHODS

This study was a secondary analysis of an observational study. Neurocognitive functioning was assessed using a battery of 7 domains (verbal fluency, executive functioning, speed of information processing, attention/working memory, memory [learning and delayed recall], and motor skills). Vascular aging was assessed using estimated markers of arterial stiffness (ie, estimated pulse wave velocity, pulse pressure, and vascular overload index). A multivariable regression adjusted for demographics, cardiovascular disease risk factors, and HIV clinical variables was used to examine the association between vascular aging and NCI outcomes.

RESULTS

Among 165 people with HIV, the mean age was 51.5 ± 6.9 years (62% men and 83% African American/Black or Other). In fully adjusted models, an increase in estimated pulse wave velocity and pulse pressure was associated with lower T scores in learning (-2.95 [-5.13, -0.77]) and working memory (-2.37 [-4.36, -0.37]), respectively. An increase in vascular overload index was associated with lower T scores in working memory (-2.33 [-4.37, -0.29]) and learning (-1.85 [-3.49, -0.21]).

CONCLUSIONS

Estimated markers of arterial stiffness were weakly associated with neurocognitive functioning, suggesting that vascular aging may have a role in cognitive decline among people with HIV.

Cancer-related cognitive impairment and wellbeing in patients with newly diagnosed aggressive lymphoma compared to population norms and healthy controls: an exploratory study

PURPOSE

There has been little dedicated research on cancer-related cognitive impairment in patients with aggressive lymphoma. We describe and compare patients' cognitive function with that of healthy controls and patients' wellbeing and distress with general population values. We also explore associations between patients' neuropsychological test performance and self-reported cognitive function and distress.

METHODS

Secondary analysis of data from a feasibility study of 30 patients with newly diagnosed aggressive lymphoma and 72 healthy controls. Patients completed neuropsychological tests and self-report measures before and 6-8 weeks after chemotherapy. Healthy controls completed neuropsychological tests and the FACT-Cog at enrolment and 6 months later. Mixed models were used to analyze neuropsychological test and FACT-Cog scores. One-sample t-tests were used to compare patients' self-reported wellbeing and distress with population norms. Associations were explored with Kendall's Tau b.

RESULTS

Patients and healthy controls were well matched on socio-demographics. Differences between neuropsychological test scores were mostly large-sized; on average, patients' scores on measures of information processing speed, executive function, and learning and memory were worse both before and after chemotherapy (all p ≤ 0.003). The same pattern was observed for impact of perceived cognitive impairment on quality-of-life (both p < 0.001). Patients' physical and emotional wellbeing scores were lower than population norms both before and after chemotherapy (all p ≤ 0.018). Associations between neuropsychological performance and other measures were mostly trivial (all p > 0.10).

CONCLUSION

For many patients with aggressive lymphoma, impaired neuropsychological test performance and impact of perceived impairments on quality-of-life precede chemotherapy and are sustained after chemotherapy. Findings support the need for large-scale longitudinal studies with this population to better understand targets for interventions to address cognitive impairments.

Intrathecal production of anti-Epstein-Barr virus viral capsid antigen IgG is associated with neurocognition and tau proteins in people with HIV

OBJECTIVE

HIV and Epstein-Barr virus (EBV) co-infection has been linked to increased immune activation and larger HIV reservoir. We assessed whether anti-EBV humoral responses are associated with increased cerebrospinal fluid (CSF) inflammation and with neurocognitive impairment (NCI) in people with HIV (PWH).

DESIGN

Cross-sectional analysis in 123 EBV-seropositive PWH either on antiretroviral therapy ( n  = 70) or not.

METHODS

Serum and CSF anti-EBV viral capsid antigen immunoglobulin G (anti-EVI) and CSF EBV DNA were measured by commercial immunoassay and RT-PCR. Seventy-eight participants without neurological confounding factors underwent neurocognitive assessment (Global Deficit Score, GDS). CSF total tau and 181-phosphorylated-tau (ptau) were measured by immunoassays together with biomarkers of blood-brain barrier (BBB) integrity, immune activation, astrocytosis, and intrathecal synthesis. Logistic and linear regressions and moderation analysis were used to investigate the relationships between CSF anti-EVI, GDS, and biomarkers.

RESULTS

Twenty-one (17.1%) and 22 participants (17.9%) had detectable CSF anti-EVI (10.5-416.0 U/ml) and CSF EBV DNA (25-971 copies/ml). After adjusting for BBB integrity, age, and clinical factors, the presence of CSF anti-EVI was only associated with serum levels of anti-EVI, and not with CSF EBV DNA. CSF anti-EVI, tau and ptau showed reciprocal interactions affecting their associations with GDS. After adjusting for demographics and clinical parameters, higher CSF anti-EVI levels were associated with worse GDS (aβ 0.45, P  < 0.001), and CSF levels of tau and ptau had a moderation effect on the strength of this association (models' P  < 0.001).

CONCLUSION

Humoral immune responses against EBV within the central nervous system may contribute to NCI in PWH through mechanisms that involve neuronal injury.

Neuropsychological longitudinal study of patients with low-grade gliomas: Cognitive impairment

This study is part of a longitudinal research program, in which patients diagnosed with low-grade gliomas (LGG: n = 13), as well as healthy controls (n = 13), were consecutively recruited and neuropsychologically followed for 7 years. The patients are followed up regardless of variations in treatment. A composite score is used (Global Deficit Score: GDS) included cognitive measures where at least five patients had a negative change: information processing speed, speed of naming, construction ability, verbal fluency, non-verbal thinking, and immediate non-verbal memory. The most important finding in this 7-year follow-up study is that two-thirds of the patients developed cognitive impairment. The remaining third of the patients showed stability in their cognitive ability and were still alive 17 years after diagnosis. Younger patients with tumors in the right frontal or posterior regions showed a more favorable development. Patients with frontal tumors and a declined GDS show also significant changes in executive functions. Given the limited number, no firm conclusions can be drawn regarding the impact of tumor localization. The impact of LGG on cognition and the survival time after diagnosis varies considerably between patients. However, most of the patients (69%) showed cognitive impairment during the seven years we followed them.

A 2-year longitudinal randomized controlled trial examining the transfer of speed of processing training to secondary cognitive domains in middle-aged and older adults with HIV-associated neurocognitive disorder: Results of the think fast study

OBJECTIVE

As people with HIV (PWH) age, they are at-risk of developing cognitive impairments compared to their seronegative counterparts. Although speed of processing (SOP) training may help improve this cognitive ability, less work has examined transfer to other cognitive domains. This study examined the effect of SOP training has on secondary cognitive domains in PWH aged 40+ years.

METHOD

In this 3-group 2-year longitudinal study, 216 PWH with HIV-associated neurocognitive disorder (HAND) or borderline HAND were randomized to either: (1) 10 h of SOP training (n = 70); (2) 20 h of SOP training (n = 73); or (3) 10 h of an active control training (n = 73). Participants completed a comprehensive cognitive battery at baseline, immediately after training, and at 1 and 2 years. This battery yielded global and domain specific T-scores as well as a cognitive impairment variable. Generalized linear mixed-effect models were fitted to estimate between-group mean differences at the follow-up time-points adjusted for baseline.

RESULTS

No clinically or statistically significant improvements in any of the cognitive outcomes were observed. A sensitivity analysis was conducted; conclusions replicated those of the main analysis, with two exceptions: Global Function T and Psychomotor Speed T showed relevant training improvements among the intervention groups over the control group at the immediate post time point.

CONCLUSIONS

Although SOP training has been shown to improve cognitive abilities that correspond to driving and mobility, such training has limited therapeutic utility in improving cognition in other domains in PWH with HAND.

Latent Profile Analysis of Cognitive Performance and Depressive Symptoms Among People with HIV

Depression and cognitive impairment are prevalent conditions among people with HIV (PWH), likely attributable to shared causes and common risk factors. Identifying subtypes of PWH with similar patterns of neurocognitive impairment (NCI) and depressive symptoms may inform development of patient-centered interventions that target-specific profiles. This study aimed to (1) classify PWH based on patterns of domain-specific NCI and depression; and (2) determine the relationship between latent class membership and pertinent clinical characteristics. PWH (N = 580, 86.2% male, 57.1% non-Hispanic White, 69.2% unemployed) completed a comprehensive neuropsychological test battery assessing global and domain-specific cognition. Domain-specific NCI was classified as deficit score >0.5. Participants completed the Beck Depression Inventory-II (BDI-II), and domain-specific BDI-II scores reflecting cognitive, affective, and somatic symptoms were computed. Latent profile analysis (LPA) was used to determine latent subgroups of NCI and depression. The optimal LPA solution consisted of five classes: minimal NCI and minimal depression (Class 1), amnestic and minimal depression (Class 2), severe multi-domain NCI and moderate depression (somatic and affective; Class 3), mild NCI and mild depression (Class 4), and moderate multi-domain NCI and severe depression (Class 5). Despite similar levels of functional impairment, Class 5 had a significant psychiatric profile, whereas Class 3 had a complex medical profile (i.e., higher frailty index, higher medications, greater proportion of AIDS diagnosis). In contrast, Class 1 had the lowest medication use and frailty index, with similar HIV disease characteristics to Classes 3 and 5. Our results suggest there are multiple pathways to cognitive and functional impairment among PWH with co-occurring depression and cognitive impairment, and these groups may respond differently to interventions. Of note, our sample was majority non-Hispanic White and male, which is nonrepresentative of the US population of PWH. Future interventions should consider a more integrated, person-centered approach that addresses cognitive and emotional health to optimize health outcomes in PWH.

Mitochondrial DNA mutation pathogenicity score and neurocognitive performance in persons with HIV

BACKGROUND

Mitochondrial DNA (mtDNA) genetic variation is associated with neurocognitive (NC) impairment (NCI) in people with HIV (PWH). Other approaches use sequence conservation and protein structure to predict the impact of mtDNA variants on protein function. We examined predicted mtDNA variant pathogenicity in the CHARTER study using MutPred scores, hypothesizing that persons with higher scores (greater predicted pathogenicity) have more NCI.

METHODS

CHARTER included NC testing in PWH from 2003 to 2007. MutPred scores were assigned to CHARTER participants with mtDNA sequence; any score > 0.5 was considered potentially deleterious. Outcomes at cohort entry were NCI, defined by global and seven NC domain deficit scores, and by mean global and domain NC performance T-scores. Univariate and multivariable regression analyses assessed associations between having a deleterious variant and NCI. Additional models included estimated peripheral blood cell mtDNA copy number.

RESULTS

Data were available for 744 PWH (357 African ancestry; 317 European; 70 Hispanic). In the overall cohort, PWH having any potentially deleterious variant were less likely to have motor impairment (16 vs. 25 %, p = 0.001). In multivariable analysis, having a deleterious variant remained associated with lower likelihood of motor impairment (adjusted odds ratio 0.59 [95 % CI 0.41-0.88]; p = 0.009), and better motor performance by T-score (β 1.71 [0.31-3.10], p = 0.02). Associations persisted after adjustment for estimated mtDNA quantity.

CONCLUSIONS

In these PWH, having a potentially deleterious mtDNA variant was associated with less motor impairment. These unexpected findings suggest that potentially deleterious mtDNA variations may confer protection against impaired motor function by as yet unknown mechanisms.

Elevated Plasma Protein Carbonyl Concentration Is Associated with More Abnormal White Matter in People with HIV

Structural brain abnormalities, including those in white matter (WM), remain common in people with HIV (PWH). Their pathogenesis is uncertain and may reflect multiple etiologies. Oxidative stress is associated with inflammation, HIV, and its comorbidities. The post-translational carbonylation of proteins results from oxidative stress, and circulating protein carbonyls may reflect this. In this cross-sectional analysis, we evaluated the associations between protein carbonyls and a panel of soluble biomarkers of neuronal injury and inflammation in plasma (N = 45) and cerebrospinal fluid (CSF, n = 32) with structural brain MRI. The volume of abnormal WM was normalized for the total WM volume (nAWM). In this multisite project, all regression models were adjusted for the scanner. The candidate covariates included demographics, HIV disease characteristics, and comorbidities. Participants were PWH on virally suppressive antiretroviral therapy (ART) and were mostly white (64.4%) men (88.9%), with a mean age of 56.8 years. In unadjusted analyses, more nAWM was associated with higher plasma protein carbonyls (p = 0.002) and higher CCL2 (p = 0.045). In the adjusted regression models for nAWM, the association with plasma protein carbonyls remained significant (FDR p = 0.018). Protein carbonyls in plasma may be a valuable biomarker of oxidative stress and its associated adverse health effects, including within the central nervous system. If confirmed, these findings would support the hypothesis that reducing oxidative stress could treat or prevent WM injury in PWH.

Automated procedure for demographic adjustments on cognitive test scores

Performances of normal people on cognitive tests are known to vary by demographic characteristics, such as age, education, and sex. Thus, cognitive test scores should be corrected for demographic influences when they are used to detect below-expected results due to disease or injury involving the central nervous system (CNS). Normative corrections, if estimated from a large, diverse, and well-characterized cohort of controls, help to remove expected differences in cognitive performance associated with normal demographic characteristics and associated socio-economic disadvantages. In this paper, we (1) describe in detail the process of generating regression-based normative standards, and its advantages and limitations, (2) provide recommendations for applying these normative standards to data from individuals and populations at risk for CNS dysfunction, and (3) introduce an R package, test2norm, that contains functions for producing and applying normative formulas to generate demographically corrected scores for measuring deviations from expected, normal cognitive performances.

Pre-treatment frontal beta events are associated with executive dysfunction improvement after repetitive transcranial magnetic stimulation for depression: A preliminary report

Repetitive transcranial magnetic stimulation (rTMS) is an established clinical treatment for major depressive disorder (MDD) that has also been found to improve aspects of executive functioning. The objective of this study was to examine whether oscillatory burst-like events within the beta band (15-29 Hz) prior to treatment could predict subsequent change in self-reported executive dysfunction (EDF) across a clinical course of rTMS for MDD. Twenty-eight adults (64% female) with MDD completed the self-report Frontal Systems Behavior Scale (FrSBe) and provided eyes-closed resting-state electroencephalography (EEG) before and after a clinical course of rTMS therapy for primary MDD. The rate, power, duration, and frequency span of transient EEG measured oscillatory beta events were calculated. Events within delta/theta and alpha bands were examined to assess for beta specificity. After controlling for improvement in primary depressive symptoms, a lower rate of beta events at F3, Fz, F4, and Cz prior to rTMS treatment was associated with a larger improvement in EDF after rTMS treatment. In addition, a decrease in beta event rate at Fz pre-to-post treatment was associated with a larger improvement in EDF after treatment. Results were largely specific to the beta band. In this study, the rate of frontrocentral beta events prior to treatment significantly predicted the likelihood of subsequent improvement in EDF symptoms following a clinical course of rTMS for MDD. These preliminary findings suggest the potential utility of EEG measured beta events and rTMS for targeting EDF across an array of neuropsychiatric disorders.

An Automated Virtual Reality Program Accurately Diagnoses HIV-Associated Neurocognitive Disorders in Older People With HIV

Background

HIV-associated neurocognitive disorders (HANDs) remain prevalent despite antiretroviral therapy, particularly among older people with HIV (PWH). However, the diagnosis of HAND is labor intensive and requires expertise to administer neuropsychological tests. Our prior pilot work established the feasibility and accuracy of a computerized self-administered virtual reality program (DETECT; Display Enhanced Testing for Cognitive Impairment and Traumatic Brain Injury) to measure cognition in younger PWH. The present study expands this to a larger sample of older PWH.

Methods

We enrolled PWH who were ≥60 years old, were undergoing antiretroviral therapy, had undetectable plasma viral loads, and were without significant neuropsychological confounds. HAND status was determined via Frascati criteria. Regression models that controlled for demographic differences (age, sex, education, race/ethnicity) examined the association between DETECT's cognition module and both HAND status and Global Deficit Score (GDS) derived via traditional neuropsychological tests.

Results

Seventy-nine PWH (mean age, 66 years; 28% women) completed a comprehensive neuropsychological battery and DETECT's cognition module. Twenty-five (32%) had HAND based on the comprehensive battery. A significant correlation was found between the DETECT cognition module and the neuropsychological battery (r = 0.45, P < .001). Furthermore, in two separate regression models, HAND status (b = -0.79, P < .001) and GDS impairment status (b = -0.83, P < .001) significantly predicted DETECT performance. Areas under the curve for DETECT were 0.78 for differentiating participants by HAND status (HAND vs no HAND) and 0.85 for detecting GDS impairment.

Conclusions

The DETECT cognition module provides a novel means to identify cognitive impairment in older PWH. As DETECT is fully immersive and self-administered, this virtual reality tool holds promise as a scalable cognitive screening battery.

Mode of HIV exposure and excess burden of neurocognitive impairment in people living with HIV: a protocol for systematic review and meta-analysis of controlled studies

BACKGROUND

Chronic HIV infection significantly elevates the risk of brain pathology, precipitating neurocognitive impairment (NCI) among people living with HIV (PLWH). The diagnosis of NCI in PLWH hinges on evaluating deviations in neuropsychological test performance in comparison to HIV-seronegative normative controls. However, the adverse psychosocial conditions experienced by PLWH can also result in reduced test performance, potentially confounding the accurate NCI attribution to HIV infection. This planned systematic review aims to investigate potential disparities in the excess burden of NCI among PLWH in two groups of studies: (a) studies enrolling controls who shared a similar mode of HIV exposure (MoHE) with the PLWH participants (MoHE-adjusted) and (b) studies enrolling normative controls or controls without undefined MoHE (MoHE-naive).

METHODS

We will systematically search five electronic databases (MEDLINE, Embase, PsycINFO, Web of Science, ProQuest) and registries (OpenGrey, ClinicalTrials.gov, ISRCTN registry). Studies reporting NCI in PLWH and HIV-seronegative controls with cross-sectional or baseline measurements, published from January 2007 to September 2023, will be included. To be classified as MoHE adjusted, a study must evidence ≥ 90% enrolment of both PLWH and their seronegative controls from the same MoHE group (e.g. men who have sex with men, people who use drugs or alcohol). Reports of test performance scores will be transformed into NCI proportions using simulated score distributions, applying a global deficit score cut-off ≥ 0.5 to estimate NCI cases. The Newcastle-Ottawa scale adapted to the purpose of the review will be used to appraise study quality. Random-effects meta-analysis will be used to pool the excess burden of NCI in prevalence ratios and test the difference between MoHE-adjusted and MoHE-naive studies. Furthermore, subgroup analyses and meta-regression will be undertaken across categorical study-level covariates (e.g. study locations, NCI diagnostic criteria) and continuous/ordinal covariates (nadir CD4, number of neurocognitive domains assessed), respectively.

DISCUSSION

This systematic review will contribute towards a greater appreciation of the unique psychosocial conditions of PLWH that are missing from the current case definition of HIV-associated neurocognitive disorder. The findings will additionally highlight possible disparities in the distribution of the excess burden of NCI by MoHE groups, thereby guiding the prioritization of mitigation efforts.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42021271358.

Psychosocial risk factors and cognitive decline in people living with HIV: results from the Malaysian HIV and aging (MHIVA) study

HIV-associated mortality has improved with the advent of antiretroviral therapy, yet neurocognitive decline persists. We assessed the association between psychosocial risk factors and cognitive function among Malaysian PLWH. Data of virally suppressed PLWH (n = 331) on stable ART, from the Malaysian HIV and Aging study was assessed. Psychosocial factors were assessed using the Lubben Social Network Scale-6 (social isolation) and Depression Anxiety Stress Scale-21 (DASS-21). The Montreal Cognitive Assessment (MoCA) with normative standards for the Malaysian population was used to determine cognitive function. Linear and logistic regression were used to assess the associations between cognition, and psychosocial risk factors. Median age of participants was 43.8 years (IQR 37.7-51.0). Participants were predominantly male (82.8%), with secondary education or higher (85.2%). Participants were on ART for 5.7 years (IQR 3.0-9.7), with a mean MoCA score of 24.6 (±3.7). Social isolation was found in 34.6% of participants, and severe depression, severe stress, and severe anxiety in 10.6%, 15.4%, and 6.0% respectively. After adjusting for demographic, clinical, and HIV parameters, MoCA scores were significantly associated with severe stress (β = -0.11, p = 0.02) and having marginal friendship ties (β = -0.13, p = 0.03). Social isolation and severe stress are associated with neurocognitive impairment in PLWH.

Alzheimer's Disease Pathology in Middle Aged and Older People with HIV: Comparisons with Non-HIV Controls on a Healthy Aging and Alzheimer's Disease Trajectory and Relationships with Cognitive Function

We determined the prevalence of Alzheimer's disease (AD) pathological hallmarks, amyloid-β and phosphorylated-Tau, in autopsied brains of 49 people with HIV (PWH) (ages: 50-68; mean age = 57.0) from the National NeuroAIDS Tissue Consortium and in a comparative cohort of 55 people without HIV (PWoH) from the UC San Diego Alzheimer's Disease Research Center (17 controls, 14 mild cognitive impairment, 24 AD; ages: 70-102, mean age = 88.7). We examined how AD pathology relates to domain-specific cognitive functions in PWH overall and in sex-stratified samples. Amyloid-β and phosphorylated-Tau positivity (presence of pathology of any type/density) was determined via immunohistochemistry in AD-sensitive brain regions. Among PWH, amyloid-β positivity ranged from 19% (hippocampus) to 41% (frontal neocortex), and phosphorylated-Tau positivity ranged from 47% (entorhinal cortex) to 73% (transentorhinal cortex). Generally, AD pathology was significantly less prevalent, and less severe when present, in PWH versus PWoH regardless of cognitive status. Among PWH, positivity for AD pathology related most consistently to memory-related domains. Positivity for p-Tau pathology related to memory-related domains in women with HIV only, although the sample size of women with HIV was small (n = 10). Results indicate that AD pathology is present in a sizable portion of middle aged and older PWH, although not to the extent in older PWoH. Studies with better age-matched PWoH are needed to examine the effect of HIV status on AD pathology.

Single nucleotide polymorphisms in aquaporin-4 associate with cognitive impairment status in people with HIV

Neurocognitive impairments are more frequent in people with HIV (PWH) compared to their uninfected counterparts. HIV-associated neurocognitive disorder (HAND) is a spectrum disorder and up to 50% of PWH are reported to suffer from HAND. Altered waste clearance from the brain, chronic neuroinflammation and impaired metabolic processes may contribute to abnormal aging in PWH and are more common among those who suffer from HAND. Thus, it is important to identify earlier predictors for development of HAND. A key contributor to cognitive impairment in HIV and in Alzheimer's disease (AD) is formation and accumulation of aberrant proteins including hyperphosphorylated Tau (pTau). Previous data from AD and traumatic brain injury studies report that impaired waste clearance from the brain contributes in part to cognitive impairments. Evidence suggests that the aquaporin 4 (aqp4) gene may have an important role in waste clearance from the brain as single nucleotide polymorphisms (SNPs) in aqp4 have been reported to associate with changes in cognitive decline in AD patients. Given some similarities between HAND and AD, we assessed potential associations of several aqp4 SNPS with cognitive impairment in PWH. Our data show that homozygous carriers of the minor allele in SNPs rs3875089 and rs3763040 had significantly lower neuropsychological test Z-scores in multiple domains compared to the other genotypes. Interestingly, this decrease in Z-scores was only observed in PWH and not in HIV-control participants. Conversely, homozygosity of the minor allele of rs335929 associated with better executive function in PWH. Based on these data, tracking large cohorts of PWH to determine if the presence of these SNPs associate with cognitive changes during disease progression is of interest. Furthermore, screening PWH for SNPs that may be associated with cognitive impairment risk after diagnosis could be considered in alignment with traditional treatment plans to potentially work on skills in areas shown to have cognitive decline with these SNPs present.

Prevalence and variability of HIV/AIDS-associated neurocognitive impairments in Africa: a systematic review and meta-analysis

BACKGROUND

HIV/AIDS-associated neurocognitive impairments negatively affect treatment adherence, viral load suppression, CD4 count, functionality, and the overall quality of life of people with seropositive status. However, huge variability is observed across primary studies regarding the prevalence and determinants of neurocognitive impairment in people with HIV/AIDS. This systematic review and meta-analysis sought to determine the pooled prevalence of neurocognitive impairment and identify factors contributing to variations in its estimate among people living with HIV/AIDS in Africa.

METHODS

A comprehensive literature search of scientific databases (Medline/PubMed, SCOPUS, Web of Science, PsycINFO, and EMBASE) was performed from inception onward. Google and Google Scholar were also searched for grey literature. Research articles available until July 15, 2022 were included. We used STATA-version 14 statistical software for analysis. A random effect model was executed to pool the reported prevalence of neurocognitive impairments. Subgroup analysis was done to show variations in the prevalence of neurocognitive impairments and factors that might contribute to these variations.

RESULTS

A literature search resulted in 8,047 articles. After the removal of duplications and thorough evaluation, a total of 49 studies were included in the meta-analysis. The prevalence of HIV/AIDS-associated neurocognitive impairments was highly variable across studies, ranging from 14% to 88%, yielding the pooled prevalence of HIV/AIDS-associated neurocognitive impairment to be 46.34% [95% CI (40.32, 52.36)] and I² = 98.5% with a P-value of 0.001.

CONCLUSIONS

A large proportion of people living with HIV/AIDS in Africa have HIV/AIDS-associated neurocognitive impairment. This illustrates the need to establish practical approaches to early identification and effective control of HIV/AIDS-associated neurocognitive impairments. However, there were variabilities in the reported prevalence of HIV/AIDS-associated neurocognitive impairments across studies. This further demonstrates the need to have consistent measurement approaches.

TRIAL REGISTRATION

PROSPERO 2022, "CRD42020166572".

Two-year clinical trial examining the effects of speed of processing training on everyday functioning in adults with human immunodeficiency virus-associated neurocognitive disorder (HAND) and borderline HAND in the U.S. Deep South: Findings of the Think Fast Study

Many people living with human immunodeficiency virus (HIV) (PLWH) experience cognitive decline that impairs everyday functioning. Cognitive training approaches, such as speed of processing (SOP) training, may reduce the impact of HIV-Associated Neurocognitive Disorder (HAND) on everyday functioning. In this experimental design study called the Think Fast Study, 216 participants age 40 and older with HAND or borderline HAND were randomized to one of three groups: (1) 10 h of SOP training (n = 70); (2) 20 h of SOP training (n = 73); or (3) 10 h of Internet Navigation Control Training (a contact control group; n = 73). Participants completed several everyday functioning measures at baseline, posttest, and year 1 and year 2 follow ups, which included: (a) Modified Lawton and Brody Activities of Daily Living (ADL) Questionnaire; (b) Timed Instrumental Activities of Daily Living (TIADL) Test; (c) Patient's Assessment of Own Functioning (PAOFI); (d) Medication Adherence Questionnaire (MAQ); and (e) Medication Adherence Visual Analog Scale (VAS). Linear mixed-effect models and generalized estimating equation models were fitted to estimate between group differences at all follow-up time points. At follow-up timepoints, those in the 10-h and 20-h training groups had better scores on medication adherence measures (MAQ and VAS) than those in the control group, with effects (Cohen's d) ranging 0.13-0.41 for MAQ and 0.02-0.43 for VAS. In conclusion, SOP training improved some indicators of everyday functioning, specifically medication adherence; however, the therapeutic effects diminished over time. Implications for practice and research are posited.

Anemia and Erythrocyte Indices Are Associated With Neurocognitive Performance Across Multiple Ability Domains in Adults With HIV

BACKGROUND

Anemia 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.

METHODS

Participants 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.

RESULTS

The 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).

CONCLUSIONS

Anemia 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.

Neurocognitive function and quality-of-life in patients with colorectal cancer

OBJECTIVE

Colorectal cancer (CRC) survivors report significant long-term physical and cognitive declines post-treatment. Our purpose was to combine task-evoked Event-Related Potential (ERP) and resting state functional magnetic resonance imaging (rsf/MRI) methodologies to characterize the physiological underpinnings and cognitive sequelae of chemotherapy-related cognitive impairment, including changes in Quality-Of-Life (QOL) in patients with CRC, as compared to healthy control (HC) participants.

METHODS

This descriptive study recruited and obtained baseline data from patients with CRC at medical and surgical oncology visits four to six weeks post-op and followed them at 12- and 24-weeks. Procedures employed ERP, pencil and paper neuropsychological testing (N-P), structural/functional rsf/MRI, and self-report QOL methodologies. Data analyses included correlations, one-way ANOVA, Chi-square tests, and linear mixed models.

RESULTS

Study participants (n = 40) across groups (n = 15, 11, 14) were balanced on age, sex, education, and race, but not ^{marital status} Several significant associations were found between changes in Dorsal Attention Network (DAN)-related ERP measures (P2, N2, N2P2, N2pc amplitudes), with QOL measures between baseline and last visits (p < 0.05-0.001). Additionally, rsf/MRI findings showed increased network activity in a single node of the DAN post-treatment, which was associated with poorer performance on N-P tests of attention and working memory, as well as a focal decline in grey matter volume in the area.

CONCLUSIONS

Our methodology revealed structural and functional changes within the DAN associated with altered spatial attention, working memory, and ability to inhibit. These disruptions may be responsible for decreased QOL ratings in patients with CRC. This study provides a putative mechanism of understanding how altered brain structural/functional relationships impact cognition, QOL, and nursing care in patients with CRC.

NCI TRIAL ID

NCI-2020-05952, University of Nebraska Medical Center, Clinical Trials.gov ID NCT03683004.

Higher Levels of Cerebrospinal Fluid and Plasma Neurofilament Light in Human Immunodeficiency Virus-Associated Distal Sensory Polyneuropathy

BACKGROUND

Neurofilament light (NFL) chain concentrations, reflecting axonal damage, are seen in several polyneuropathies but have not been studied in human immunodeficiency virus (HIV) distal sensory polyneuropathy (DSP). We evaluated NFL in cerebrospinal fluid (CSF) and plasma in relation to DSP in people with HIV (PWH) from 2 independent cohorts and in people without HIV (PWoH).

METHODS

Cohort 1 consisted of PWH from the CHARTER Study. Cohort 2 consisted of PWH and PWoH from the HIV Neurobehavioral Research Center (HNRC). We evaluated DSP signs and symptoms in both cohorts. Immunoassays measured NFL in CSF for all and for plasma as well in Cohort 2.

RESULTS

Cohort 1 consisted of 111 PWH, mean ± SD age 56.8 ± 8.32 years, 15.3% female, 38.7% Black, 49.6% White, current CD4+ T-cells (median, interquartile range [IQR]) 532/µL (295, 785), 83.5% with plasma HIV RNA ≤50 copies/mL. Cohort 2 consisted of 233 PWH of similar demographics to PWH in Cohort 1 but also 51 PWoH, together age 58.4 ± 6.68 years, 41.2% female, 18.0% Black, Hispanic, non-Hispanic White 52.0%, 6.00% White. In both cohorts of PWH, CSF and plasma NFL were significantly higher in both PWH with DSP signs. Findings were similar, albeit not significant, for PWoH. The observed relationships were not explained by confounds.

CONCLUSIONS

Both plasma and CSF NFL were elevated in PWH and PWoH with DSP. The convergence of our findings with others demonstrates that NFL is a reliable biomarker reflecting peripheral nerve injury. Biomarkers such as NFL might provide, validate, and optimize clinical trials of neuroregenerative strategies in HIV DSP.

The Evolution of Assessing Central Nervous System Complications in Human Immunodeficiency Virus: Where Do We Go From Here?

In this fifth decade of the human immunodeficiency virus (HIV) epidemic, central nervous system (CNS) complications including cognitive impairment and mental health remain a burden for people with HIV (PWH) on antiretroviral therapy. Despite the persistence of these complications, which often co-occur, the underlying pathophysiology remains elusive and consequently treatments remain limited. To continue to grow our understanding of the underlying mechanisms of CNS complications among PWH, there is a need to reexamine our current approaches, which are now more than 2 decades old. At the 2021 National Institutes of Health-sponsored meeting on Biotypes of CNS Complications in PWH, the Neurobehavioral Working Group addressed the following: (1) challenges inherent to determining CNS complications; (2) heterogeneity in CNS complications; and (3) problems and solutions for examining integrated biotypes. The review below provides a summary of the main points presented and discussed by the Neurobehavioral Working Group at the meeting.

Twelve-year neurocognitive decline in HIV is associated with comorbidities, not age: a CHARTER study

Modern antiretroviral therapy (ART) has increased longevity of people with HIV and shifted the age distribution of the HIV pandemic upward toward that of the general population. This positive development has also led to concerns about premature and/or accelerated neurocognitive and physical ageing due to the combined effects of chronic HIV, accumulating comorbidities, adverse effects or possible toxicities of ART and biological ageing. Here we present results of comprehensive assessments over 12 years of 402 people with HIV in the CNS HIV ART Effects Research (CHARTER) programme, who at follow-up were composed of younger (<60 years) and older (≥60 years) subgroups. Over the 12 years, ART use and viral suppression increased in both subgroups as did systemic and psychiatric comorbidities; participants in both subgroups also evidenced neurocognitive decline beyond what is expected in typical ageing. Contrary to expectations, all these adverse effects were comparable in the younger and older CHARTER subgroups, and unrelated to chronological age. Neurocognitive decline was unrelated to HIV disease or treatment characteristics but was significantly predicted by the presence of comorbid conditions, specifically diabetes, hypertension, chronic pulmonary disease, frailty, neuropathic pain, depression and lifetime history of cannabis use disorder. These results are not consistent with premature or accelerated neurocognitive ageing due to HIV itself but suggest important indirect effects of multiple, potentially treatable comorbidities that are more common among people with HIV than in the general population. Good medical management of HIV disease did not prevent these adverse outcomes, and increased attention to a range of comorbid conditions in people with HIV may be warranted in their care.

Blood and cerebrospinal fluid biomarker changes in patients with HIV-associated neurocognitive impairment treated with lithium: analysis from a randomised placebo-controlled trial

HIV-associated neurocognitive disorders (HAND) persist in the era of antiretroviral therapy (ART). Thus, ART does not completely halt or reverse the pathological processes behind HAND. Adjuvant mitigating treatments are, therefore, prudent. Lithium treatment is known to promote neuronal brain-derived neurotrophic factors (BDNF). Lithium is also an inhibitor of glycogen synthase kinase-3 beta (GSK-3-β). We analyzed biomarkers obtained from participants in a randomized placebo-controlled trial of lithium in ART-treated individuals with moderate or severe HAND. We assayed markers at baseline and 24 weeks across several pathways hypothesized to be affected by HIV, inflammation, or degeneration. Investigated biomarkers included dopamine, BDNF, neurofilament light chain, and CD8 + lymphocyte activation (CD38 + HLADR +). Alzheimer's Disease (AD) biomarkers included soluble amyloid precursor protein alpha and beta (sAPPα/β), Aβ38, 40, 42, and ten other biomarkers validated as predictors of mild cognitive impairment and progression in previous studies. These include apolipoprotein C3, pre-albumin, α1-acid glycoprotein, α1-antitrypsin, PEDF, CC4, ICAM-1, RANTES, clusterin, and cystatin c. We recruited 61 participants (placebo = 31; lithium = 30). The age baseline mean was 40 (± 8.35) years and the median CD4 + T-cell count was 498 (IQR: 389-651) cells/μL. Biomarker concentrations between groups did not differ at baseline. However, both groups' blood dopamine levels decreased significantly after 24 weeks (adj. p < 002). No other marker was significantly different between groups, and we concluded that lithium did not confer neuroprotection following 24 weeks of treatment. However, the study was limited in duration and sample size.

Meaningful cognitive decline is uncommon in virally suppressed HIV, but sustained impairment, subtle decline and abnormal cognitive aging are not

BACKGROUND

High antiretroviral therapy (ART) coverage and viral suppression among people with HIV (PWH) in Australia provide a unique context to study individual cognitive trajectories, cognitive aging and factors associated with longitudinal cognitive function during chronic and stable HIV disease.

METHODS

Participants from the Predictors of Adherence to Antiretroviral Therapy study (n = 457, recruited between September 2013 and November 2015, median age = 52 years, and all with HIV RNA <50 copies mL) completed a cognitive assessment with CogState Computerized Battery (CCB) at baseline, Month-12, and Month-24. Demographics, psycho-social and socioeconomic factors, healthcare seeking behaviors, HIV disease characteristics and comorbidities were assessed. The CCB data were corrected for age, sex and practice effect and averaged into a global z-score (GZS). Cognitive impairment was defined with the global deficit score method (GDS>0.5). Meaningful cognitive change was statistically defined (decline or improvement versus stability, i.e., 90% CI, that is p < 0.05, 2-tailed) using a novel evidence-based change score: the linear mixed-effect regression (LMER)-based GZS change score. A separate LMER model with a top-down variable selection approach identified the independent effects of age and other demographic, HIV disease characteristics, socioeconomic and health-related factors on the demographically corrected GZS. The combined definitions of change and cross-sectional impairment enabled the identification of cognitive trajectories.

FINDINGS

At Month-12 and Month-24, 6% and 7% showed meaningful cognitive decline and 4% and 3% improved respectively. Only 1% showed sustained decline. Incident impairment due to subtle cognitive decline (i.e., below the threshold of meaningful cognitive decline) was 31% and 25% at Month-12 and Month-24, while 14% showed sustained impairment (i.e., cognitively impaired at all study visits). Older age (≥50 years) and time interaction was associated with lower demographically corrected GZS (β = -0.31, p < 0.001). Having a regular relationship, excellent English proficiency, and perceived stigma (avoidance) were associated with higher GZS (all p < 0.05). Relying on government subsidy, severe depression, and lower belief in ART necessity and higher concerns were associated with lower GZS (all p < 0.05). No HIV disease characteristics had a significant effect.

INTERPRETATIONS

Meaningful cognitive decline was not different from normal expectation in chronic stable HIV disease. Despite this, subtle cognitive decline, sustained cognitive impairment, and greater than normative-age cognitive aging were evident.

FUNDING

Funding for the PAART study was provided in part by unrestricted educational grants from Gilead Sciences (www.gilead.com) (Grant Number: IN-AU-264- 0131), the Balnaves Foundation (www.balnavesfoundation.com), the Victorian Department of Health and Human Services (Australia) (www.dhs.vic.gov.au/home), Western Australia Health (www.health.wa.gov.au), the ACT Ministry of Health (Australia) (www.health.act.gov.au), and in-kind support from the Queensland Department of Health (Australia) (www.health.qld.gov.au), and NHMRC Partnership grant APP1058474 (PI: Carr, Andrew).

Can individualized-targeted computerized cognitive training improve everyday functioning in adults with HIV-associated neurocognitive disorder?

Half of people with human immunodeficiency virus (HIV) have HIV-associated neurocognitive disorder (HAND). Fortunately, cognitive training programs can improve function across cognitive domains, which may translate to everyday functioning. The Training on Purpose (TOPS) Study was designed to reverse HAND by targeting cognitive training to specific cognitive impairments that contributed to the diagnosis. A secondary aim of TOPS was to determine whether such cognitive training improved subjective and objective everyday functioning. In this two-group pre-post experimental design study, 109 adults with HAND were randomized to either: (1) a no-contact control group (no training) or (2) the Individualized-Targeted Cognitive Training group. Each participant received approximately 10 hours of cognitive training in two selected cognitive domains based on her/his individual baseline cognitive performance. Thus, 20 hours of individualized training on these two cognitive domains occurred over a course of 12 weeks in 1-2 hour sessions. Specific to the secondary aim of TOPS, measures of everyday functioning were administered before and after cognitive training to examine transfer effects. The analyses revealed that in general, speed of processing training produced benefits in everyday functioning as measured by the medication adherence visual analogue scale and the Timed Instrumental Activities of Daily Living test. Inconsistent findings were found for the other seven cognitive training protocols in either improving everyday functioning or reducing perceived everyday functioning; however, there may be other contributing factors that obscured such effects needing further research. This study demonstrated that some training protocols vary in efficacy in altering both objective and subjective everyday functioning ability.

A practitioner's guide to geospatial analysis in a neuroimaging context

Introduction

Health disparities arise from biological-environmental interactions. Neuroimaging cohorts are reaching sufficiently large sample sizes such that analyses could evaluate how the environment affects the brain. We present a practical guide for applying geospatial methods to a neuroimaging cohort.

Methods

We estimated brain age gap (BAG) from structural magnetic resonance imaging (MRI) from 239 city-dwelling participants in St. Louis, Missouri. We compared these participants to population-level estimates from the American Community Survey (ACS). We used geospatial analysis to identify neighborhoods associated with patterns of altered brain structure. We also evaluated the relationship between Area Deprivation Index (ADI) and BAG.

Results

We identify areas in St. Louis, Missouri that were significantly associated with higher BAG from a spatially representative cohort. We provide replication code.

Conclusion

We observe a relationship between neighborhoods and brain health, which suggests that neighborhood-based interventions could be appropriate. We encourage other studies to geocode participant information to evaluate biological-environmental interaction.

Cognitive Intra-individual Variability in HIV: an Integrative Review

Nearly 30-50% of people living with HIV experience HIV-Associated Neurocognitive Disorder (HAND). HAND indicates performance at least one standard deviation below the normative mean on any two cognitive domains. This method for diagnosing or classifying cognitive impairment has utility, however, cognitive intraindividual variability provides a different way to understand cognitive impairment. Cognitive intraindividual variability refers to the scatter in cognitive performance within repeated measures of the same cognitive test (i.e., inconsistency) or across different cognitive tests (i.e., dispersion). Cognitive intraindividual variability is associated with cognitive impairment and cognitive decline in various clinical populations. This integrative review of 13 articles examined two types of cognitive intraindividual variability in people living with HIV, inconsistency and dispersion. Cognitive intraindividual variability appears to be a promising approach to detect subtle cognitive impairments that are not captured by traditional mean-based neuropsychological testing. Greater intraindividual variability in people living with HIV has been associated with: 1) poorer cognitive performance and cognitive decline, 2) cortical atrophy, both gray and white matter volume, 3) poorer everyday functioning (i.e., driving simulation performance), specifically medication adherence, and 4) even mortality. This inspires future directions for research. First, greater cognitive intraindividual variability may reflect a greater task demand on executive control to harness and regulate cognitive control over time. By improving executive functioning through cognitive training, it may reduce cognitive intraindividual variability which could slow down cognitive decline. Second, cognitive intraindividual variability may be reconsidered in prior cognitive intervention studies in which only mean-based cognitive outcomes were used. It is possible that such cognitive interventions may actually improve cognitive intraindividual variability, which could have clinical relevance.

Association of apolipoprotein E epsilon 4 and cognitive impairment in adults living with human immunodeficiency virus: a meta-analysis

BACKGROUND

It is controversial whether the apolipoprotein E epsilon 4 allele (APOE ε4) is a risk gene for human immunodeficiency virus (HIV)-related neurocognitive impairment. This meta-analysis aimed to summarize evidence of the associations between APOE ε4 and cognitive impairment in people living with HIV (PLWH).

METHODS

Our study conducted a systematic literature search of PubMed, Web of Science, Embase, Google Scholar, and ProQuest for studies published before April 11, 2022 that evaluated associations between APOE ε4 and cognitive impairment in adult PLWH (aged ≥18 years). We calculated pooled odds ratios (ORs) of global cognitive impairment and 95% confidence intervals (CIs) and standardized mean differences (SMDs) for specific cognitive domains between APOE ε4 carriers and non-carriers. Subgroup meta-analyses were used to evaluate the result profiles across different categorical variables.

RESULTS

Twenty studies met the inclusion criteria, including 19 that evaluated global cognitive impairment. APOE ε4 was significantly associated with global cognitive impairment in PLWH (OR = 1.36, 95% CI = [1.05, 1.78], number of estimates [k] = 19, P = 0.02, random effects). Subgroup meta-analysis based percentage of females showed evident intergroup differences in global cognitive performance between ε4 carriers and non-carriers (P = 0.015). APOE ε4 carriers had lower cognitive test scores than non-carriers in all seven cognitive domains, including fluency (SMD = -0.51, 95% CI = [-0.76, -0.25], P < 0.001, k = 4, I2 = 0%), learning (SMD = -0.52, 95% CI = [-0.75, -0.28], P < 0.001, k = 5, I2 = 0%), executive function (SMD = -0.41, 95% CI = [-0.59, -0.23], P < 0.001, k = 8, I2 = 0%), memory (SMD = -0.41, 95% CI = [-0.61, -0.20], P < 0.001, k = 10, I2 = 36%), attention/working memory (SMD = -0.34, 95% CI = [-0.54, -0.14], P = 0.001, k = 6, I2 = 0%), speed of information processing (SMD = -0.34, 95% CI = [-0.53, -0.16], P < 0.001, k = 8, I2 = 0%), and motor function (SMD = -0.19, 95% CI = [-0.38, -0.01], P = 0.04, k = 7, I2 = 0%).

CONCLUSIONS

Our meta-analysis provides significant evidence that APOE ε4 is a risk genotype for HIV-associated cognitive impairment, especially in cognitive domains of fluency, learning, executive function, and memory. Moreover, the impairment is sex specific.

META ANALYSIS REGISTRATION

PROSPERO, CRD 42021257775.

Psychological resilience is an independent correlate of health-related quality of life in middle-aged and older adults with HIV in the Deep South

Older people living with HIV (PLWH) are at risk for poorer health-related quality of life (HRQoL). Psychological resilience may protect HRQoL in this population. The sample included 174 predominately African American PLWH (age 40-73). Results indicated associations between resilience, socioeconomic status, cognitive performance, instrumental activities of daily living, personality, and depressive symptoms. HIV factors (e.g. viral load, duration of HIV) were not associated with resilience. Adjusting for confounders, resilience was associated with mental HRQoL. Understanding factors associated with resilience among older PLWH and the translation of resilience to HRQoL may inform interventions to improve well-being among individuals aging with HIV.

Validation of the National Institute of Health Toolbox Cognition Battery (NIHTB-CB) in Children and Adolescents with and without HIV Infection in Lusaka, Zambia

The objective of this study was to validate the NIH Toolbox Cognition Battery (NIHTB-CB) in Zambian children with and without HIV-infection. Children living with HIV and HIV-exposed, uninfected (HEU) children completed traditional neuropsychological and NIHTB-CB tasks. Using pairwise correlation and a linear regression model we measured associations between traditional measure composite scores and parental ratings of children's abilities, and NIHTB-CB scores. A Receiver Operating Characteristic (ROC) curve was developed to identify participants with impairment. 389 children, 8-17 years old participated. NIHTB-CB and traditional measures converged well as a whole and when comparing analogous individual tests across the two batteries. The NIHTB-CB composite score discriminated between the groups and was positively associated with external criteria for cognitive function: parental ratings of intelligence and school performance. Some English vocabulary and/or an unfamiliar cultural context presented challenges. NIHTB-CB was associated with children's everyday cognitive abilities, though future use may require linguistic and cultural adaptation.

Examining virtual driving test performance and its relationship to individuals with HIV-associated neurocognitive disorders

Significance

Existing screening tools for HIV-associated neurocognitive disorders (HAND) are often clinically impractical for detecting milder forms of impairment. The formal diagnosis of HAND requires an assessment of both cognition and impairment in activities of daily living (ADL). To address the critical need for identifying patients who may have disability associated with HAND, we implemented a low-cost screening tool, the Virtual Driving Test (VDT) platform, in a vulnerable cohort of people with HIV (PWH). The VDT presents an opportunity to cost-effectively screen for milder forms of impairment while providing practical guidance for a cognitively demanding ADL.

Objectives

We aimed to: (1) evaluate whether VDT performance variables were associated with a HAND diagnosis and if so; (2) systematically identify a manageable subset of variables for use in a future screening model for HAND. As a secondary objective, we examined the relative associations of identified variables with impairment within the individual domains used to diagnose HAND.

Methods

In a cross-sectional design, 62 PWH were recruited from an established HIV cohort and completed a comprehensive neuropsychological assessment (CNPA), followed by a self-directed VDT. Dichotomized diagnoses of HAND-specific impairment and impairment within each of the seven CNPA domains were ascertained. A systematic variable selection process was used to reduce the large amount of VDT data generated, to a smaller subset of VDT variables, estimated to be associated with HAND. In addition, we examined associations between the identified variables and impairment within each of the CNPA domains.

Results

More than half of the participants (N = 35) had a confirmed presence of HAND. A subset of twenty VDT performance variables was isolated and then ranked by the strength of its estimated associations with HAND. In addition, several variables within the final subset had statistically significant associations with impairment in motor function, executive function, and attention and working memory, consistent with previous research.

Conclusion

We identified a subset of VDT performance variables that are associated with HAND and assess relevant functional abilities among individuals with HAND. Additional research is required to develop and validate a predictive HAND screening model incorporating this subset.

Cognitive and Physiologic Reserve Independently Relate to Superior Neurocognitive Abilities in Adults Aging With HIV

BACKGROUND

To investigate joint contributions of cognitive and physiologic reserve to neurocognitive SuperAging in older persons with HIV (PWH).

METHODS

Participants 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.

RESULTS

Univariably, 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).

CONCLUSIONS

Each 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.

Class-Based Antiretroviral Exposure and Cognition Among Women Living with HIV

Neurologic complications of the human immunodeficiency virus (HIV) are common in treated individuals, and toxicity of certain antiretroviral therapies (ART) may contribute to cognitive impairment. We investigated exposures to specific ART and cognition among women living with HIV (WLWH). Virologically suppressed (viral load <200 copies/mL during at least two semi-annual visits) WLWH and age/race matched HIV-seronegative controls enrolled in the Women's Interagency HIV Study who completed at least two biennial cognitive assessments were included. Analysis of WLWH was restricted to those with exposure to the drug class of interest and a nucleoside reverse transcriptase inhibitor (NRTI) backbone. Generalized estimating equations were used to evaluate repeated measures of cognition over time in association with ART class exposure. Among 1,242 eligible WLWH, 20% (n = 247) had isolated drug exposure to non-nucleoside reverse transcriptase inhibitors (NNRTI), 18% (n = 219) to protease inhibitors (PIs), and 6% (n = 79) to integrase inhibitors with a NRTI backbone. Cognitive assessments were performed at a median of 3 biennial visits {IQR 2-4 visits}. At the index assessment, 21% of WLWH demonstrated global cognitive impairment versus 29% at their last cognitive assessment. In multivariable analyses adjusted for hypertension, depression, diabetes mellitus, history of AIDS-defining illness, alcohol use, number of medications, and time on ART, WLWH exposed to NNRTIs demonstrated verbal learning improvements (mean T-score change 1.3, p = .020) compared to other treated women. Compared to HIV-seronegative women, WLWH exposed to PIs had worse verbal learning (mean T-score difference -2.62, p = .002) and verbal memory performance (mean T-score difference -1.74, p = .032) at baseline. Compared to HIV-seronegative women, WLWH exposed to PIs had improvements in verbal learning (mean T-score slope difference 0.36, p = .025) and verbal memory (mean T-score slope difference 0.32, p = .042). The index T-score and slope of change in the T-score were similar among other treated groups and the HIV-seronegative group. We noted emerging trends in cognition in WLWH exposed to specific drug classes. Ongoing study of this relatively young group is important to characterize long-term cognitive outcomes and effect of antiretrovirals as treatment guidelines evolve.

Identification of Youthful Neurocognitive Trajectories in Adults Aging with HIV: A Latent Growth Mixture Model

Despite the neurocognitive risks of aging with HIV, initial cross-sectional data suggest a subpopulation of older people with HIV (PWH) possess youthful neurocognition (NC) characteristic of SuperAgers (SA). Here we characterize longitudinal NC trajectories of older PWH and their convergent validity with baseline SA status, per established SuperAging criteria in PWH, and baseline biopsychosocial factors. Growth mixture modeling (GMM) identified longitudinal NC classes in 184 older (age ≥ 50-years) PWH with 1–5 years of follow-up. Classes were defined using ‘peak-age’ global T-scores, which compare performance to a normative sample of 25-year-olds. 3-classes were identified: Class 1_{Stable Elite} (n = 31 [16.8%], high baseline peak-age T-scores with flat trajectory); Class 2_{Quadratic Average} (n = 100 [54.3%], intermediate baseline peak-age T-scores with u-shaped trajectory); Class 3_{Quadratic Low} (n = 53 [28.8%], low baseline peak-age T-scores with u-shaped trajectory). Baseline predictors of Class 1_{Stable Elite} included SA status, younger age, higher cognitive and physiologic reserve, and fewer subjective cognitive difficulties. This GMM analysis supports the construct validity of SuperAging in older PWH through identification of a subgroup with longitudinally-stable, youthful neurocognition and robust biopsychosocial health.

A Randomized Clinical Trial on the Impact of Individually Targeted Computerized Cognitive Training on Quality of Life Indicators in Adults With HIV-Associated Neurocognitive Disorder in the Southeastern United States

ABSTRACT

HIV-associated neurocognitive disorder (HAND) is experienced by 30% to 50% of people living with HIV (PLWH), potentially affecting their quality of life (QoL). In the Training on Purpose Study, we investigated whether targeted cognitive training can improve QoL in PLWH with HAND. Using a two-group experimental design, we randomized 109 adults with HAND to either (a) the Individualized-Targeted Cognitive Training group or (b) a no-contact control group. Those in the training group were assigned 10 hr of cognitive training per two selected cognitive domains (20 hr total) for which impairment was observed. Overall, two patterns emerged. First, significant improvements in measures of everyday cognitive complaints, depression, and mental health were consistently observed after the completion of many cognitive training protocols. Second, immediate and delayed spatial learning and memory training resulted in more significant indicators of QoL improvements compared with the other cognitive domain trainings. The findings suggest that some types of cognitive training may have advantages over others in improving aspects of QoL.

Functional compartmentalization of antibodies in the central nervous system during chronic HIV infection

The central nervous system (CNS) has emerged as a critical HIV reservoir. Thus, interventions aimed at controlling and eliminating HIV must include CNS-targeted strategies. Given the inaccessibility of the brain, efforts have focused on cerebrospinal fluid (CSF), aimed at defining biomarkers of HIV-disease in the CNS, including HIV-specific antibodies. However, how antibodies traffic between the blood and CNS, and whether specific antibody profiles track with HIV-associated neurocognitive disorders (HAND) remains unclear. Here, we comprehensively profiled HIV-specific antibodies across plasma and CSF from 20 antiretroviral therapy (ART) naive or treated persons with HIV. CSF was populated by IgG1 and IgG3 antibodies, with reduced Fc-effector profiles. While ART improved plasma antibody functional coordination, CSF profiles were unaffected by ART and were unrelated to HAND severity. These data point to a functional sieving of antibodies across the blood-brain barrier, providing previously unappreciated insights for the development of next-generation therapeutics targeting the CNS reservoir.

The association between benzodiazepine use and greater risk of neurocognitive impairment is moderated by medical burden in people with HIV

Benzodiazepine use is linked to neurocognitive impairment (NCI) in the general population and people with HIV (PWH); however, this relationship may depend on age-related factors such as medical comorbidities, which occur at an elevated rate and manifest earlier in PWH. We retrospectively examined whether chronological age or medical burden, a clinical marker for aging, moderated the relationship between benzodiazepine use and NCI in PWH. Participants were 435 PWH on antiretroviral therapy who underwent neurocognitive and medical evaluations, including self-reported current benzodiazepine use. A medical burden index score (proportion of accumulated multisystem deficits) was calculated from 28 medical deficits. Demographically corrected cognitive deficit scores from 15 neuropsychological tests were used to calculate global and domain-specific NCI based on established cut-offs. Logistic regressions separately modeled global and domain-specific NCI as a function of benzodiazepine x age and benzodiazepine x medical burden interactions, adjusting for current affective symptoms and HIV disease characteristics. A statistically significant benzodiazepine x medical burden interaction (p = .006) revealed that current benzodiazepine use increased odds of global NCI only among those who had a high medical burden (index score > 0.3 as indicated by the Johnson–Neyman analysis), which was driven by the domains of processing speed, motor, and verbal fluency. No age x benzodiazepine interactive effects on NCI were present. Findings suggest that the relationship between BZD use and NCI among PWH is specific to those with greater medical burden, which may be a greater risk factor for BZD-related NCI than chronological age.

Genome-wide variants and polygenic risk scores for cognitive impairment following blood or marrow transplantation

Cognitive impairment is prevalent in blood or marrow transplantation (BMT) recipients, albeit with inter-individual variability. We conducted a genome-wide association study of objective cognitive function assessed longitudinally in 239 adult BMT recipients for discovery and replicated in an independent cohort of 540 BMT survivors. Weighted genome-wide polygenic risk scores (PRS) were constructed using linkage disequilibrium pruned significant SNPs. Forty-four genome-wide significant SNPs were identified using additive (n = 3); codominant (n = 20) and genotype models (n = 21). Each additional copy of a risk allele was associated with a 0.28-point (p = 1.07 × 10^-8) to a 1.82-point (p = 6.7 × 10^-12) increase in a global deficit score. We replicated two SNPs (rs11634183 and rs12486041) with links to neural integrity. Patients in the top PRS quintile were at increased risk of cognitive impairment in discovery (RR = 1.95, 95%CI: 1.28-2.96, p = 0.002) and replication cohorts (OR = 1.84, 95%CI, 1.02-3.32, p = 0.043). Associations were stronger among individuals with lowest clinical risk for cognitive impairment. These findings support potential utility of PRS-based risk classification in the development of targeted interventions aimed at improving cognitive outcomes in BMT survivors.

Reduction in cerebral oxygen metabolism in subcortical regions may be a biomarker of cognitive decline in people living with human immunodeficiency virus

BACKGROUND AND PURPOSE

Regional cerebral blood flow (rCBF) and oxygen metabolism (rCMRO₂ ) in whole brain, white matter, gray matter and lenticular nuclei were studied in people living with human immunodeficiency virus (PLHIV) as well as HIV-associated neurocognitive disorder (HAND).

METHODS

Treatment-naïve PLHIV underwent neurocognitive assessment and magnetic resonance (MR) measurement of rCBF and rCMRO₂ with repeat after 12 months of antiretroviral therapy (ART). Age- and sex-matched controls underwent single MR measurements. Regional CBF and rCMRO₂ were compared amongst symptomatic, asymptomatic, normal HAND and controls using analysis of variance. Longitudinal analysis of HAND worsening (≥1 category) was assessed after 12 months of ART and correlated with rCBF and rCMRO₂ measured by MR imaging using the paired-sample t test.

RESULTS

Thirty PLHIV completed baseline and 12-month assessments (29 with rCMRO₂ measurement). At baseline HAND assessment, 13% had no cognitive impairment, 27% had asymptomatic neurocognitive impairment, 60% had mild neurocognitive disorder and none had HIV-associated dementia. At 12 months, 13% had no cognitive impairment, 20% had asymptomatic neurocognitive impairment, 50% had mild neurocognitive disorder and 17% had HIV-associated dementia. In those without HAND worsening (N = 21) rCMRO₂ remained stable and in those with HAND worsening (N = 8) rCMRO₂ measurement declined from baseline to 12 months in white matter (2.05 ± 0.40 to 1.73 ± 0.51, p = 0.03) and lenticular nuclei (4.32 ± 0.39 to 4.00 ± 0.51, p = 0.05).

CONCLUSIONS

In recently diagnosed PLHIV, no association was found between rCBF or rCMRO₂ and cognitive impairment at baseline. There was a reduction in rCMRO₂ in those with worsening of cognitive function at 12 months on ART. Reduction in rCMRO₂ may be a biomarker of cognitive decline in PLHIV.

Polygenic networks in peripheral leukocytes indicate patterns associated with HIV infection and context-dependent effects of cannabis use

In spite of suppressive antiretroviral therapies (ART), Human Immunodeficiency Virus (HIV)-infected subjects still experience the consequences of viral persistence and chronic inflammation. In the brain, where most HIV-1 targets are of innate immune origin, neurological and cognitive impairments are detectable and enhanced by highly prevalent substance use disorders. Cannabis is one of the most prevalent substances among HIV+ ​subjects, compared to non-infected populations, either prescribed for improving various symptoms or used recreationally, as well as a component of polysubstance use. The mechanisms by which addictive substances and HIV interact are multifactorial and poorly understood. Importantly, the HIV brain target cells, macrophages and microglia, express receptors to neurotransmitters elevated by such drugs, and express receptors to cannabinoids, particularly CB2R. We have tested a panel of 784 transcripts associated with neurological disorders, digitally multiplexed and detectable in peripheral blood cells from a small cohort (n ​= ​102) of HIV-positive (HIV+) and HIV-negative (HIV-) specimens, stratified based on criteria of lifetime (LT) dependence of cannabis (CAN+) or not (CAN-). Demographic homogeneity and low incidence of co-morbidities helped increase power and allowed the identification of key differences consistent with HIV infection, cannabis exposure, or their interactions. A small percentage of these subjects used cannabis as well as other drugs. The data was analyzed using robust systems and visualization strategies to detect orchestrated patterns in gene networks connected based on molecular interfaces with higher power than in single genes. We found that the effects of cannabis differed drastically between HIV- and HIV+ ​groups, particularly in gene networks playing a role in inflammation, neurodegeneration, apoptosis and leukocyte adhesion and transmigration. At the level of individual genes, we identified detrimental effects that were associated with polysubstance use as a covariate, particularly methamphetamine. Transcription factor usage predictions suggest that the effects of cannabis are associated with transcriptional co-regulation at the gene promoters by multiple factors that vary by context. Overall, we have found that the effects of cannabis may be context-dependent, with potential benefits in the context of HIV reflected by improvements in cognition, but in the absence of the polysubstance use component.

The impacts of HIV infection, age, and education on functional brain networks in adults with HIV

HIV-associated neurocognitive disorders (HAND) remain highly prevalent in people with HIV (PWH). Studies suggested that certain sociodemographic factors are associated with the risk of HAND in PWH. Here we investigated the impact of HIV infection and demographics on functional brain networks. One run of 8.5 min resting state functional MRI (fMRI) data was collected from 101 PWH (41-70 years old) and 40 demographically comparable controls. Functional connectivity (FC) was calculated using average wavelet coherence. The impact of demographic factors on FCs was investigated using canonical correlation analysis (CCA). Wavelet coherence analysis revealed a reduced within-network connectivity in the dorsal somatomotor network (dSMN), along with a reduced between-network connectivity between dSMN and medial temporal lobe (MTL) in PWH (compared to controls). Across all participants, CCA revealed that older age and HIV infection had negative impacts on network connectivity measures (mainly reduced within- and between-network FCs), whereas education had an opposite effect. In addition, being female at birth or a member of a minority ethnic/racial group was also associated with network disruptions. Our data suggested that advanced age and HIV infection are risk factors for functional brain network disruptions, whereas higher educational attainment was linked to better preserved functional network connectivity.

A Haptoglobin Exon Copy Number Variant Associates With HIV-Associated Neurocognitive Impairment in European and African-Descent Populations

A common two-exon deletion distinguishes the gene encoding the free hemoglobin capturing protein—haptoglobin (HP)–into two alleles: HP1 and HP2. To evaluate the impact of this copy number variant (CNV) on neurocognitive impairment (NCI) in people living with HIV, we imputed this variant in 432 European-descent (EUR) and 491 African-descent (AFR) participants from the CNS HIV Antiretroviral Therapy Effects Research Study using an optimized imputation pipeline and evaluated its associations with NCI. At baseline, in AFR, the HP2 allele decreased the odds of NCI (defined by a global deficit score, GDS, ⩾0.5; Odds Ratio, OR = 0.584, p = 0.022). However, in EUR, HP2 increased the odds (OR = 2.081, p = 0.040) of NCI suggesting a detrimental effect. These effects were extended to longitudinal analyses using repeated measurements where the protective effect of the HP2 allele in AFR became marginally significant (p = 0.054) and in EUR the detrimental effect increased in significance (p = 0.037). In EUR, the HP2 allele slightly reduced the risk of NCI over time (OR = 0.028 per allele per year, p = 0.024). Further analyses of cognitive domain-specific impairment revealed that the HP-NCI effect was based on changes in learning, speed of information processing, and verbal domains over time differing by ancestry groups. Overall, these findings suggest that these functional HP CNV alleles influence the likelihood of NCI and contribute to changes in neurocognitive function over time in people living with HIV.

Relationship of the balloon analog risk task to neurocognitive impairment differs by HIV serostatus and history of major depressive disorder

HIV and major depressive disorder (MDD) commonly co-occur and are both linked to greater risk-taking behavior, possibly due to neurocognitive impairment (NCI). The present study examined the concordance of the Balloon Analog Risk Task (BART), a gold standard measure of risk-taking propensity, with NCI and real-world sexual risk behaviors in PWH with comorbid MDD. Participants included 259 adults, stratified by HIV serostatus (HIV + /HIV −) and lifetime MDD (MDD + /MDD −), who completed neuropsychological testing, the BART, and sexual risk behavior questionnaires. Logistic regression, stratified by HIV serostatus, examined joint effects of MDD and BART (linear and quadratic) on NCI. Follow-up linear regressions examined sexual risk behavior and neurocognitive domain T-scores as correlates of the BART. NCI prevalence was lowest in HIV − /MDD − , but BART scores did not differ by HIV/MDD status. In the HIV + group, BART performance predicted NCI such that high and low BART scores related to greater odds of NCI, but only in dual-risk HIV + /MDD + individuals. HIV + /MDD + individuals with both low and high BART scores exhibited poorer learning and recall, whereas processing speed and executive function were only poor in low BART risk-taking HIV + /MDD + . Higher BART scores linearly related to higher sexual risk behaviors only in MDD + individuals, independent of HIV serostatus. Low and high risk-taking on the BART may reflect discrete neurocognitive profiles in HIV + /MDD + individuals, with differential implications for real-world sexual risk behavior. HIV and comorbid MDD may disturb corticostriatal circuits responsible for integrating affective and neurocognitive components of decision-making, thereby contributing to risk-averse and risk-taking phenotypes.

Rates of Cognitive and Functional Impairments in Older Adults Residing in a Continuing Care Senior Housing Community

OBJECTIVE

The current cross-sectional study examined cognition and performance-based functional abilities in a continuing care senior housing community (CCSHC) that is comparable to other CCSHCs in the US with respect to residents' demographic characteristics.

METHOD

Participants were 110 older adult residents of the independent living unit. We assessed sociodemographics, mental health, neurocognitive functioning, and functional capacity.

RESULTS

Compared to normative samples, participants performed at or above expectations in terms of premorbid functioning, attention span and working memory, processing speed, timed set-shifting, inhibitory control, and confrontation naming. They performed below expectation in verbal fluency and verbal and visual learning and memory, with impairment rates [31.4% (>1 SD below the mean) and 18.49% (>1.5 SD below the mean)] well above the general population (16% and 7%, respectively). Within the cognitive test battery, two tests of delayed memory were most predictive of a global deficit score. Most cognitive test scores correlated with performance-based functional capacity.

CONCLUSIONS

Overall, results suggest that a subset of older adults in the independent living sector of CCSHCs are cognitively and functionally impaired and are at risk for future dementia. Results also argue for the inclusion of memory tests in abbreviated screening batteries in this population. We suggest that CCSHCs implement regular cognitive screening procedures to identify and triage those older adults who could benefit from interventions and, potentially, a transition to a higher level of care.

Socioeconomic Status and Cognitive Function in Children With HIV: Evidence From the HIV-Associated Neurocognitive Disorders in Zambia (HANDZ) Study

BACKGROUND

Multiple previous studies have identified a detrimental effect of pediatric HIV on cognitive function. Socioeconomic status (SES) is one of the strongest predictors of cognitive performance and may affect the relationship between HIV and cognition.

METHODS

As part of the ongoing HIV-Associated Neurocognitive Disorders in Zambia (HANDZ) study, a prospective cohort study, we recruited 208 participants with HIV and 208 HIV-exposed uninfected controls, all aged 8-17 years. A standardized questionnaire was administered to assess SES, and all participants had comprehensive neuropsychological testing. An NPZ8 score was derived as a summary measure of cognitive function. Logistic regression and linear regression were used to model the relationship between SES and cognitive function, and mediation analysis was used to identify specific pathways by which SES may affect cognition.

RESULTS

Children with HIV performed significantly worse on a composite measure of cognitive function (NPZ8 score -0.19 vs. 0.22, P < 0.001) and were more likely to have cognitive impairment (33% vs. 19%, P = 0.001). Higher SES was associated with reduced risk of cognitive impairment (odds ratio 0.8, 95% confidence interval: 0.75-0.92, P < 0.001) in both groups, with similar effects in children with HIV and HIV-exposed uninfected groups. SES was more strongly correlated with NPZ8 score in children with HIV than in uninfected controls (Pearson's R 0.39 vs. 0.28), but predicted NPZ8 in both groups. Mediation analysis suggested that the effect of SES on cognition was most strongly mediated through malnutrition.

CONCLUSIONS

Cognitive function is strongly correlated with SES in children with HIV, suggesting a synergistic effect of HIV and poverty on cognitive function.