Heterogeneity in neurocognitive change trajectories among people with HIV starting antiretroviral therapy in Rakai, Uganda

Sex-specific associations between cerebrospinal fluid inflammatory biomarkers and cognition in antiretroviral-naïve people with HIV in rural Uganda

Globally, people with HIV (PWH) experience a broad spectrum of cognitive impairment that can be noted both before and after initiation of antiretroviral therapy (ART). Sex differences in immune function have been implicated in differential cognitive outcomes. Here, we report sex differences in cerebrospinal fluid (CSF) markers in relation to cognitive performance in a subset of ART-naïve PWH participating in the Rakai Neurology Cohort Study. Participants (55 % male, 45 % female, overall mean age 36.5 years, SD = 8.7) underwent a lumbar puncture and a cognitive battery prior to ART initiation. CSF was collected, and 14 inflammatory markers were analyzed. Individual cognitive test z-scores were generated based on local normative data. We used a series of least absolute shrinkage and selection operator (lasso) regressions to examine associations between CSF inflammatory markers and cognitive outcomes. CSF inflammatory levels did not differ significantly between sexes except for IL-8 being higher in men. In women with HIV, there were more significant associations between inflammatory markers and cognitive performance than men with HIV. Additionally, inflammatory markers were associated with a broader range of cognitive domains in women compared to men with HIV. Patterns of association differed by sex in this young, ART-naïve Ugandan cohort, and several associations in a particular sex persisted or shifted when compared to a post-ART timepoint. Further study into sex-specific patterns of inflammation is warranted to improve cognitive outcomes in PWH.

Imaging the translocator protein 18 kDa within cognitive control and declarative memory circuits in virally suppressed people with HIV

OBJECTIVES

Virally suppressed people with HIV (VS-PWH) show heterogeneity in patterns of cognitive dysfunction. To better understand the relationship between the neuroimmune response and cognition, we used PET to image the translocator protein 18 kDa (TSPO). The study examined HIV-serostatus differences in TSPO as well as associations between regional TSPO and select cognitive processes defined using the Research Domain Criteria (RDoC) framework.

DESIGN

Cross-sectional investigation in VS-PWH ( n  = 25) versus HIV-uninfected individuals ( n  = 18) of cognitive control and declarative memory, as well as [ 11 C]DPA-713 PET measures of TSPO within cognitive control and declarative memory regions of interest (ROI).

METHODS

Group differences in [ 11 C]DPA-713 binding ( VT ) in cognitive control or declarative memory regions were examined using linear mixed models. Tests of associations between factor-derived cognitive system measures and PET measures were performed, controlling for TSPO genotype.

RESULTS

There were no group differences in any of the four factor-derived cognitive system measures. VS-PWH had higher log [ 11 C]DPA-713 VT across cognitive control regions [unstandardized beta coefficient reflecting mean difference [ B ] = 0.23, SE = 0.11, 95% confidence interval (CI) 0.01-0.45, P  = 0.04] and declarative memory regions ( B   =  0.24, SE = 0.11, 95% CI 0.02-0.45, P  = 0.03). Higher log [ 11 C]DPA-713 VT in cognitive control regions related to poorer cognitive control in each group, and to worse self-reported cognitive performance in VS-PWH. Log [ 11 C]DPA-713 VT in each declarative memory region did not associate with measured declarative memory.

CONCLUSION

A localized neuroimmune response marked by high TSPO in brain regions that subserve cognitive control may contribute to poorer cognitive control in VS-PWH.

Development of a refined harmonization approach for longitudinal cognitive data in people with HIV

OBJECTIVES

The aim of this study was to develop a refined method for harmonizing longitudinal cognitive data across several large-scale studies in people with HIV (PWH), in whom cognitive complications are common and heterogeneous in presentation.

STUDY DESIGN AND SETTING

We developed a refined method for harmonizing longitudinal cognitive data across five large-scale studies in PWH that used different cognitive batteries with only some overlapping tests-Women's Interagency HIV Study (WIHS), Multicenter AIDS Cohort Study, CNS HIV Antiretroviral Therapy Effects Research (CHARTER), National NeuroAIDS Tissue Consortium, and the HIV Neurobehavioral Research Program. Traditional data harmonization methods using latent variable models focus on cross-sectional data and require the presence of common cognitive tests to serve as "linking" assessments. However, the absence of such common tests for certain cognitive domains can preclude the direct application of these traditional techniques. To address these challenges, we developed a harmonization method that leveraged a second-order factor model, which capitalized on the structural relationships among cognitive domains.

RESULTS

Our approach yielded harmonized cognitive domain scores that are demographically consistent across different cohorts and exhibit strong correlations with the raw or log transformed (eg, timed outcomes) cognitive test scores. These harmonized scores accurately reflected variations according to age, educational status, and other demographic factors, while preserving participants' longitudinal cognitive trajectories.

CONCLUSION

Our harmonization methods are essential for future analyses of large-scale, retrospective data to understand the heterogeneity in cognitive complications in PWH. These methods can be applied to harmonize new datasets with similar measures.

Mental health phenotypes of well-controlled HIV in Uganda

Introduction

The phenotypic expression of mental health (MH) conditions among people with HIV (PWH) in Uganda and worldwide are heterogeneous. Accordingly, there has been a shift toward identifying MH phenotypes using data-driven methods capable of identifying novel insights into mechanisms of divergent MH phenotypes among PWH. We leverage the analytic strengths of machine learning combined with inferential methods to identify novel MH phenotypes among PWH and the underlying explanatory features.

Methods

A total of 277 PWH (46% female, median age = 44; 93% virally suppressed [<50copies/mL]) were included in the analyses. Participants completed the Patient Health Questionnaire (PHQ-9), Beck Anxiety Inventory (BAI), and the PTSD Checklist-Civilian (PCL-C). A clustering pipeline consisting of dimension reduction with UMAP followed by HBDScan was used to identify MH subtypes using total symptom scores. Inferential statistics compared select demographic (age, sex, education), viral load, and early life adversity between clusters.

Results

We identified four MH phenotypes. Cluster 1 (n = 76; PTSD phenotype) endorsed clinically significant PTSD symptoms (average PCL-C total score > 33). Clusters 2 (n = 32; anxiety phenotype) and 3 (n = 130; mixed anxiety/depression phenotype) reported minimal PTSD symptoms, with modest BAI (Cluster 2) and PHQ-9 (Cluster 3) elevations. Cluster 4 (n = 39; minimal symptom phenotype) reported no clinical MH symptom elevations. Comparisons revealed higher rates of sexual abuse during childhood among the PTSD phenotype vs. the minimal symptom phenotype (p = 0.03).

Discussion

We identified unique MH phenotypes among PWH and confirmed the importance of early life adversity as an early risk determinant for unfavorable MH among PWH in adulthood.

The Impact of Cannabis Use on Cognition in People with HIV: Evidence of Function-Dependent Effects and Mechanisms from Clinical and Preclinical Studies

PURPOSE OF REVIEW

Cannabis may have beneficial anti-inflammatory effects in people with HIV (PWH); however, given this population's high burden of persisting neurocognitive impairment (NCI), clinicians are concerned they may be particularly vulnerable to the deleterious effects of cannabis on cognition. Here, we present a systematic scoping review of clinical and preclinical studies evaluating the effects of cannabinoid exposure on cognition in HIV.

RECENT FINDINGS

Results revealed little evidence to support a harmful impact of cannabis use on cognition in HIV, with few eligible preclinical data existing. Furthermore, the beneficial/harmful effects of cannabis use observed on cognition were function-dependent and confounded by several factors (e.g., age, frequency of use). Results are discussed alongside potential mechanisms of cannabis effects on cognition in HIV (e.g., anti-inflammatory), and considerations are outlined for screening PWH that may benefit from cannabis interventions. We further highlight the value of accelerating research discoveries in this area by utilizing translatable cross-species tasks to facilitate comparisons across human and animal work.

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.

Biotypes of HIV-associated neurocognitive disorders based on viral and immune pathogenesis

PURPOSE OF REVIEW

HIV-associated neurocognitive disorders (HAND) continues to be prevalent in people living with HIV despite antiretroviral therapy. However, understanding disease mechanisms and identifying therapeutic avenues has been challenging. One of the challenges is that HAND is a heterogeneous disease and that patients identified with similar impairments phenotypically may have very different underlying disease processes. As the NeuroAIDS field is re-evaluating the approaches used to identify patients with HIV-associated neurological impairments, we propose the subtyping of patients into biotypes based on viral and immune pathogenesis.

RECENT FINDINGS

Here we review the evidence supporting subtyping patients with HIV-associated neurological complications into four biotypes: macrophage-mediated HIV encephalitis, CNS viral escape, T-cell-mediated HIV encephalitis, and HIV protein-associated encephalopathy.

SUMMARY

Subtyping patients into subgroups based on biotypes has emerged as a useful approach for studying heterogeneous diseases. Understanding biotypes of HIV-associated neurocognitive impairments may therefore enable better understanding of disease mechanisms, allow for the development of prognostic and diagnostic markers, and could ultimately guide therapeutic decisions.

HIV Disease Dynamics and Markers of Inflammation and CNS Injury During Primary HIV Infection and Their Relationship to Cognitive Performance

INTRODUCTION

Early systemic and central nervous system viral replication and inflammation may affect brain integrity in people with HIV, leading to chronic cognitive symptoms not fully reversed by antiretroviral therapy (ART). This study examined associations between cognitive performance and markers of CNS injury associated with acute HIV infection and ART.

METHODS

HIV-infected MSM and transgender women (average age: 27 years and education: 13 years) enrolled within 100 days from the estimated date of detectable infection (EDDI). A cognitive performance (NP) protocol was administered at enrollment (before ART initiation) and every 24 weeks until week 192. An overall index of cognitive performance (NPZ) was created using local normative data. Blood (n = 87) and cerebrospinal fluid (CSF; n = 29) biomarkers of inflammation and neuronal injury were examined before ART initiation. Regression analyses assessed relationships between time since EDDI, pre-ART biomarkers, and NPZ.

RESULTS

Adjusting for multiple comparisons, shorter time since EDDI was associated with higher pre-ART VL and multiple biomarkers in plasma and CSF. NPZ scores were within the normative range at baseline (NPZ = 0.52) and at each follow-up visit, with a modest increase through week 192. Plasma or CSF biomarkers were not correlated with NP scores at baseline or after ART.

CONCLUSIONS

Biomarkers of CNS inflammation, immune activation, and neuronal injury peak early and then decline during acute HIV infection, confirming and extending results of other studies. Neither plasma nor CSF biomarkers during acute infection corresponded to NP scores before or after sustained ART in this cohort with few psychosocial risk factors for cognitive impairment.

Tablet-Based Cognitive Impairment Screening for Adults With HIV Seeking Clinical Care: Observational Study

BACKGROUND

Neurological complications including cognitive impairment persist among people with HIV on antiretrovirals; however, cognitive screening is not routinely conducted in HIV clinics.

OBJECTIVE

Our objective for this study was 3-fold: (1) to determine the feasibility of implementing an iPad-based cognitive impairment screener among adults seeking HIV care, (2) to examine the psychometric properties of the tool, and (3) to examine predictors of cognitive impairment using the tool.

METHODS

A convenience sample of participants completed Brain Baseline Assessment of Cognition and Everyday Functioning (BRACE), which included (1) Trail Making Test Part A, measuring psychomotor speed; (2) Trail Making Test Part B, measuring set-shifting; (3) Stroop Color, measuring processing speed; and (4) the Visual-Spatial Learning Test. Global neuropsychological function was estimated as mean T score performance on the 4 outcomes. Impairment on each test or for the global mean was defined as a T score ≤40. Subgroups of participants repeated the tests 4 weeks or >6 months after completing the first test to evaluate intraperson test-retest reliability and practice effects (improvements in performance due to repeated test exposure). An additional subgroup completed a lengthier cognitive battery concurrently to assess validity. Relevant factors were abstracted from electronic medical records to examine predictors of global neuropsychological function.

RESULTS

The study population consisted of 404 people with HIV (age: mean 53.6 years; race: 332/404, 82% Black; 34/404, 8% White, 10/404, 2% American Indian/Alaskan Native; 28/404, 7% other and 230/404, 58% male; 174/404, 42% female) of whom 99% (402/404) were on antiretroviral therapy. Participants completed BRACE in a mean of 12 minutes (SD 3.2), and impairment was demonstrated by 34% (136/404) on Trail Making Test A, 44% (177/404) on Trail Making Test B, 40% (161/404) on Stroop Color, and 17% (67/404) on Visual-Spatial Learning Test. Global impairment was demonstrated by 103 out of 404 (25%). Test-retest reliability for the subset of participants (n=26) repeating the measure at 4 weeks was 0.81 and for the subset of participants (n=67) repeating the measure almost 1 year later (days: median 294, IQR 50) was 0.63. There were no significant practice effects at either time point (P=.20 and P=.68, respectively). With respect for validity, the correlation between global impairment on the lengthier cognitive battery and BRACE was 0.63 (n=61; P<.001), with 84% sensitivity and 94% specificity to impairment on the lengthier cognitive battery.

CONCLUSIONS

We were able to successfully implement BRACE and estimate cognitive impairment burden in the context of routine clinic care. BRACE was also shown to have good psychometric properties. This easy-to-use tool in clinical settings may facilitate the care needs of people with HIV as cognitive impairment continues to remain a concern in people with HIV.

Improvement in depressive symptoms after antiretroviral therapy initiation in people with HIV in Rakai, Uganda

Depression is common following HIV infection and often improves after ART initiation. We aimed to identify distinct dimensions of depression that change following ART initiation in persons with HIV (PWH) with minimal comorbidities (e.g., illicit substance use) and no psychiatric medication use. We expected that dimensional changes in improvements in depression would differ across PWH. In an observational cohort in Rakai, Uganda, 312 PWH (51% male; mean age = 35.6 years) completed the Center for Epidemiologic Studies-Depression (CES-D) scale before and up to 2 years after ART initiation. Twenty-two percent were depressed (CES-D scores ≥ 16) pre-ART that decreased to 8% after ART. All CES-D items were used in a latent class analysis to identify subgroups with similar change phenotypes. Two improvement phenotypes were identified: affective-symptom improvement (n = 58, 19%) and mixed-symptom improvement (effort, appetite, irritability; n = 41, 13%). The affect-improvement subgroup improved on the greatest proportion of symptoms (76%). A third subgroup was classified as no-symptom changes (n = 213, 68%) as they showed no difference is symptom manifestation from baseline (93% did not meet depression criteria) to post-ART. Factors associated with subgroup membership in the adjusted regression analysis included pre-ART self-reported functional capacity, CD4 count, underweight BMI, hypertension, female sex(P's < 0.05). In a subset of PWH with CSF, subgroup differences were seen on Aβ-42, IL-13, and IL-12. Findings support that depression generally improves following ART initiation; however, when improvement is seen the patterns of symptom improvement differ across PWH. Further exploration of this heterogeneity and its biological underpinning is needed to evaluate potential therapeutic implications of these differences.

Prevalence of Severe Neurocognitive Impairment and Its Association with Socio-Demographics and Functionality Among Ugandan Older Persons: A Hospital-Based Study

BACKGROUND

The prevalence of neurocognitive disorders, especially dementia, is rising due to an increase in longevity. Early detection and diagnosis of neurocognitive impairments are important for early interventions and appropriate management of reversible causes, especially by the primary health workers. However, this study aimed to determine the prevalence and associated factors of severe neurocognitive impairment among elderly persons attending a tertiary hospital in Uganda.

METHODS

This cross-sectional survey was conducted in a Ugandan hospital setting, where older adults go for treatment for their chronic health problems. Following the inclusion criteria, interviews were conducted, where information about socio-demographics was collected, whereas neurocognitive impairment and functionality were assessed by Mini-Mental State Examination and Barthel Index, respectively. Chi-square test, Pearson correlation test, and logistic regression were performed to determine the factors associated with severe neurocognitive impairment.

RESULTS

A total of 507 elderly persons aged 60 years and above were enrolled in this study (mean age 68.62 ±7.95 years), and the prevalence of severe neurocognitive impairment was 28.01%. Advanced age, female gender, lower education level, and functional dependency were significantly associated with severe neurocognitive impairment.

CONCLUSION

Severe neurocognitive impairment is prevalent among Ugandan hospital attending elderlies with functional dependency. This suggests a need to routinely screen cognitive disorders among older persons who visit the healthcare facilities with other physical complaints to enable early detection and treatment of reversible causes of neurocognitive impairment, such as depression and delirium to enable better functionality.

Assessment, prevalence, and correlates of frailty among middle-aged adults with HIV in rural Uganda

We investigated the prevalence and risk factors for frailty among people with HIV (PWH) in rural Uganda (n = 55, 47% male, mean age 44 years). Frailty was defined according to the Fried criteria with self-reported physical activity level replacing the Minnesota Leisure Time Activity Questionnaire. Alternate classifications for physical activity utilized were the sub-Saharan Africa Activity Questionnaire and the International Physical Activity Questionnaire. Eleven participants (19%) were frail. Frail participants were older (p < 0.001), less likely to be on antiretroviral therapy (p = 0.03), and had higher rates of depression (p < .001) and HIV-associated neurocognitive disorder (p = 0.003). Agreement between physical activity measures was sub-optimal. Prevalence of frailty was high among PWH in rural Uganda, but larger sample sizes and local normative data are needed.

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

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Networks strengths predicted global cognitive performance in PWH.

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Model generalized to data from an independent PWH sample.

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

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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.

Neurocognitive Effects of Antiretroviral Initiation Among People Living With HIV in Rural Uganda

BACKGROUND

HIV-associated neurocognitive disorders remain prevalent despite effective antiretroviral therapy (ART), but there are limited longitudinal data on people living with HIV (PLWH) in sub-Saharan Africa. We examined neuropsychological (NP) performance in PLWH in a longitudinal study in Uganda.

METHODS

Participants enrolled through the Rakai Community Cohort Study (400 ART-naive PLWH and 400 matched HIV-negative persons) were administered NP assessments. In 2017, PLWH who had initiated ART underwent a 2-year follow-up assessment. Demographically adjusted Z-scores for each NP test were established using data from the HIV- controls. Multivariable linear and logistic regressions were conducted to examine group differences in NP performance. Mixed-effects regressions were conducted to examine ART-related changes in NP outcomes.

RESULTS

Of 333 PLWH who returned for their 2-year follow-up visit, 312 (94%) had initiated ART. Those on ART had a mean age of 35.6 years (SD ± 8.5 years) and mean education of 5.4 years (SD ± 3.3 years); 49% were women. ART-associated NP improvements occurred in verbal learning and memory (P's < 0.05), motor (P's < 0.01), and some measures of processing speed (P = 0.002), whereas there were declines in attention/working memory (P's < 0.001) and semantic fluency (P < 0.001). Pre-ART CD4 count and efavirenz use were associated with a more impaired change in NP performance.

CONCLUSIONS

PLWH in this resource-limited setting showed improved neurocognitive performance on most NP tests after ART initiation. However, the declines in attention/working memory and fluency performance, as well as relationship to efavirenz, warrant further study.

Associations between Antiretrovirals and Cognitive Function in Women with HIV

Cognitive complications persist in antiretroviral therapy(ART)-treated people with HIV. However, the pattern and severity of domain-specific cognitive performance is variable and may be exacerbated by ART-mediated neurotoxicity. 929 women with HIV(WWH) from the Women's Interagency HIV Study who were classified into subgroups based on sociodemographic and longitudinal behavioral and clinical data using semi-parametric latent class trajectory modelling. Five subgroups were comprised of: 1) well-controlled HIV with vascular comorbidities(n = 116); 2) profound HIV legacy effects(CD4 nadir <250 cells/μL; n = 275); 3) primarily <45 year olds with hepatitis C(n = 165); 4) primarily 35-55 year olds(n = 244), and 5) poorly-controlled HIV/substance use(n = 129). Within each subgroup, we fitted a constrained continuation ratio model via penalized maximum likelihood to examine adjusted associations between recent ART agents and cognition. Most drugs were not associated with cognition. However, among the few drugs, non-nucleoside reverse transcriptase inhibitor (NNRTIs) and protease inhibitors(PIs) were most commonly associated with cognition, followed by nucleoside reverse transcriptase inhibitors(NRTIs) and integrase inhibitors(IIs). Directionality of ART-cognition associations varied by subgroup. Better psychomotor speed and fluency were associated with ART for women with well-controlled HIV with vascular comorbidities. This pattern contrasts women with profound HIV legacy effects for whom poorer executive function and fluency were associated with ART. Motor function was associated with ART for younger WWH and primarily 35-55 year olds. Memory was associated with ART only for women with poorly-controlled HIV/substance abuse. Findings demonstrate interindividual variability in ART-cognition associations among WWH and highlight the importance of considering sociodemographic, clinical, and behavioral factors as an underlying contributors to cognition. Are antiretroviral agents a risk factor for cognitive complications in women with HIV? We examind associations between ART-agents and cognitive function among similar subgroups of women with HIV from the Women's Interagency HIV study. The patterns of associations depended on sociodemographic, clinical, and behavioral characteristics of women.

Sex-specific associations between cerebrospinal fluid inflammatory marker levels and cognitive function in antiretroviral treated people living with HIV in rural Uganda

People with HIV (PWH) taking antiretroviral therapy (ART) have persistent cognitive impairment. The prevalence of cognitive impairment is higher in women with HIV (WWH) compared to men with HIV (MWH), possibly due to sex differences in immune function. Here we report sex differences in cerebrospinal fluid (CSF) immune markers in relation to cognitive performance. A subset of 83 PWH on ART (52% WWH; mean age = 37.6 years, SD = 7.9) from the Rakai community cohort study Cohort and Rakai Health Sciences Program supported clinics in rural Uganda completed a neuropsychological (NP) assessment and a lumbar puncture. CSF was used to measure 16 cytokines/chemokines. Individual NP test z-scores were generated based on local normative data. A series of least absolute shrinkage and selection operator (lasso) regressions examined associations between CSF inflammatory markers and NP outcomes. Overall, there were no sex differences in CSF inflammatory marker levels. However, MWH displayed more associations between inflammatory markers and cognitive performance than WWH. Among MWH, inflammatory markers were associated with a number of cognitive domains, including attention, processing speed, fluency, executive function, learning and memory. MIP-1β, INF-γ, GM-CSF, IL-7 and IL-12p70 were associated with multiple domains. Among WWH, few inflammatory markers were associated cognition. Degree of associations between CSF inflammatory biomarkers and cognitive performance varied by sex in this young, ART-treated, Ugandan cohort. Further investigation into sex-specific inflammatory mechanisms of cognitive impairment among PWH is warranted to inform sex-specific management strategies.

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.

Lifetime antiretroviral exposure and neurocognitive impairment in HIV

Despite the availability of modern antiretroviral therapy (ART), neurocognitive impairment persists among some persons with HIV (PWH). We investigated the role of exposure to four major classes of ARTs in neurocognitive impairment in PWH. A single-site cohort of 343 PWH was recruited. Lifetime ART medication history was obtained from medical health records. We evaluated the role of ART exposure as a predictor of neurocognitive impairment using univariate analyses and machine learning, while accounting for potential effects of demographic, clinical, and comorbidity-related risk factors. Out of a total of 26 tested variables, two random forest analyses identified the most important characteristics of a neurocognitively impaired group (N = 59): Compared with a neurocognitively high-performing group (N = 132; F₁-score = 0.79), we uncovered 13 important risk factors; compared with an intermediate-performing group (N = 152; F₁-score = 0.75), 16 risk factors emerged. Longer lifetime ART exposure, especially to integrase inhibitors, was one of the most important predictors of neurocognitive impairment in both analyses (rank 2 of 13 and rank 4 of 16, respectively), superseding effects of age (rank 11/13, rank 15/16) and HIV duration (rank 13/13, rank 16/16). Concerning specific integrase inhibitors, the impaired group had significantly longer dolutegravir exposure (p = 0.011) compared with the high-performing group (p = 0.012; trend compared with the intermediate group p = 0.063). A longer duration to integrase inhibitor intake was negatively related to cognition in this cohort. Our findings suggest that possible cognitive complications of long-term exposure to integrase inhibitors, in particular dolutegravir, should be closely monitored in PWH.