Real-world impact of neurocognitive deficits in acute and early HIV infection

A 2-Year Longitudinal Randomized Control Trial of Speed of Processing Cognitive Training in Aging Adults with HIV-Associated Neurocognitive Disorder: Results of the Think Fast Study

Nearly 40% of people with HIV (PWH) experience HIV-associated Neurocognitive Disorder (HAND). In this 3-group efficacy study, 216 PWH 40 + years with 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 Internet navigation training (n = 73; contact control group). Participants were administered a measure of SOP [i.e., the Useful Field of View Test (UFOV®)] at baseline, at posttest immediately after training, and at year 1 and year 2 follow up. Intent-to-treat linear mixed-effect models with subject-specific intercept and slope were fitted to estimate between-group mean differences at the follow-up time-points. At the post-intervention time-point, small beneficial SOP training effects were observed for the 10-h group in UFOV® total (d = 0.28, p = 0.002). Effects were of larger magnitude for the 20-h group in these same outcomes [UFOV® total (d = 0.43, p < 0.001)]. These results indicated better benefit with more training. No intervention effect was observed at year 1. At year 2, beneficial effects of small magnitude were observed again in the 10-h group [UFOV® total (d = 0.22, p = 0.253)] with larger small-to-moderate magnitude in the 20-h group [UFOV® total (d = 0.32, p = 0.104)]. This study suggests that SOP training can improve a key indicator of this cognitive performance and that treatment gains are small-to-moderate over a two-year period. Prior literature suggests slower SOP is predictive of impairment in everyday functioning in older PWH; such an approach could potentially improve everyday functioning in PWH.

Preventing Cognitive Decline in Older Latino Adults With HIV Through a Culturally Tailored Health Promotion Intervention: Protocol for a Single-Arm Pilot Trial

BACKGROUND

Older Latino adults with HIV are at increased risk for mild cognitive impairment and earlier onset of aging-related cognitive decline. Improvements in cognitive functioning and cognitive outcomes are possible among people with HIV who adopt health promotion behaviors. However, health promotion interventions for older Latino adults with HIV have not been extensively used or widely recognized as viable treatment options. Happy Older Latinos are Active (HOLA) is a multicomponent, health promotion intervention that is uniquely tailored for older Latino adults with HIV.

OBJECTIVE

This study aims to (1) determine the feasibility and acceptability of an adapted version of HOLA aimed at improving cognitive functioning among older Latino adults with HIV; (2) explore whether HOLA will produce changes in cognitive functioning; (3) explore whether HOLA will produce changes in activity, psychosocial functioning, or biomarkers of cognition; and (4) explore whether changes in activity, psychosocial functioning or cognitive biomarkers correlate with changes in cognition, while accounting for genetic risk for dementia.

METHODS

A single-arm pilot trial with 30 Latino (aged 50 years and older) men and women with HIV was conducted to assess feasibility, acceptability, and preliminary effects on cognition. Participants were assessed at 2 time points (baseline and postintervention) on measures of neurocognitive and psychosocial functioning. In addition, blood samples were collected to determine biomarkers of cognition at baseline and postintervention. Successful recruitment was defined as meeting 100% of the targeted sample (N=30), with 20% (n=6) or less of eligible participants refusing to participate. Adequate retention was defined as 85% (n=25) or more of participants completing the postintervention assessment and acceptability was defined as 80% (n=38) or more of sessions attended by participants.

RESULTS

Participant recruitment began on February 22, 2022, and was completed on August 15, 2022. The last study visit took place on February 20, 2023. Data analysis is currently ongoing.

CONCLUSIONS

Encouraging findings from this exploratory study may provide a blueprint for scaling up the HOLA intervention to a larger cohort of older Latino adults with HIV who may be currently experiencing or are at risk for HIV-related cognitive challenges.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04791709; https://clinicaltrials.gov/study/NCT04791709.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/55507.

Extracellular vesicles produced by HIV-1 Nef-expressing cells induce myelin impairment and oligodendrocyte damage in the mouse central nervous system

HIV-associated neurocognitive disorders (HAND) are a spectrum of cognitive impairments that continue to affect approximately half of all HIV-positive individuals despite effective viral suppression through antiretroviral therapy (ART). White matter pathologies have persisted in the ART era, and the degree of white matter damage correlates with the degree of neurocognitive impairment in patients with HAND. The HIV protein Nef has been implicated in HAND pathogenesis, but its effect on white matter damage has not been well characterized. Here, utilizing in vivo, ex vivo, and in vitro methods, we demonstrate that Nef-containing extracellular vesicles (Nef EVs) disrupt myelin sheaths and inflict damage upon oligodendrocytes within the murine central nervous system. Intracranial injection of Nef EVs leads to reduced myelin basic protein (MBP) staining and a decreased number of CC1 + oligodendrocytes in the corpus callosum. Moreover, cerebellar slice cultures treated with Nef EVs exhibit diminished MBP expression and increased presence of unmyelinated axons. Primary mixed brain cultures and enriched oligodendrocyte precursor cell cultures exposed to Nef EVs display a decreased number of O4 + cells, indicative of oligodendrocyte impairment. These findings underscore the potential contribution of Nef EV-mediated damage to oligodendrocytes and myelin maintenance in the pathogenesis of HAND.

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.

Emotional health and its association with neurocognition in Hispanic and non-Hispanic White people with HIV

OBJECTIVE

Emotional functioning is linked to HIV-associated neurocognitive impairment, yet research on this association among diverse people with HIV (PWH) is scant. We examined emotional health and its association with neurocognition in Hispanic and White PWH.

METHODS

Participants included 107 Hispanic (41% primarily Spanish-speakers; 80% Mexican heritage/origin) and 216 White PWH (Overall age: M = 53.62, SD = 12.19; 86% male; 63% AIDS; 92% on antiretroviral therapy). Emotional health was assessed via the National Institute of Health Toolbox (NIHTB)-Emotion Battery, which yields T-scores for three factor-based summary scores (negative affect, social satisfaction, and psychological well-being) and 13 individual component scales. Neurocognition was measured via demographically adjusted fluid cognition T-scores from the NIHTB-cognition battery.

RESULTS

27%-39% of the sample had problematic socioemotional summary scores. Hispanic PWH showed less loneliness, better social satisfaction, higher meaning and purpose, and better psychological well-being than Whites (ps <.05). Within Hispanics, Spanish-speakers showed better meaning and purpose, higher psychological well-being summary score, less anger hostility, but greater fear affect than English speakers. Only in Whites, worse negative affect (fear affect, perceived stress, and sadness) was associated with worse neurocognition (p <.05); and in both groups, worse social satisfaction (emotional support, friendship, and perceived rejection) was linked with worse neurocognition (p <.05).

CONCLUSION

Adverse emotional health is common among PWH, with subgroups of Hispanics showing relative strengths in some domains. Aspects of emotional health differentially relate to neurocogntition among PWH and cross-culturally. Understanding these varying associations is an important step towards the development of culturally relevant interventions that promote neurocognitive health among Hispanic PWH.

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.

The Combined Effects of Cannabis, Methamphetamine, and HIV on Neurocognition

OBJECTIVE

Methamphetamine and cannabis are two widely used substances among people living with HIV (PLWH). Whereas methamphetamine use has been found to worsen HIV-associated neurocognitive impairment, the effects of combined cannabis and methamphetamine use disorder on neurocognition in PLWH are not understood. In the present study, we aimed to determine the influence of these substance use disorders on neurocognition in PLWH and to explore if methamphetamine-cannabis effects interacted with HIV status.

METHOD AND PARTICIPANTS

After completing a comprehensive neurobehavioral assessment, PLWH (n = 472) were stratified by lifetime methamphetamine (M-/M+) and cannabis (C-/C+) DSM-IV abuse/dependence disorder into four groups: M-C- (n = 187), M-C+ (n = 68), M+C-, (n = 82), and M+C+ (n = 135). Group differences in global and domain neurocognitive performances and impairment were examined using multiple linear and logistic regression, respectively, while holding constant other covariates that were associated with study groups and/or cognition. Data from participants without HIV (n = 423) were added, and mixed-effect models were used to examine possible interactions between HIV and substance use disorders on neurocognition.

RESULTS

Compared with M+C+, M+C- performed worse on measures of executive functions, learning, memory, and working memory and were more likely to be classified as impaired in those domains. M-C- performed better than M+C+ on measures of learning and memory but worse than M-C+ on measures of executive functions, learning, memory, and working memory. Detectable plasma HIV RNA and nadir CD4 < 200 were associated with lower overall neurocognitive performance, and these effects were greater for M+C+ compared with M-C-.

CONCLUSIONS

In PLWH, lifetime methamphetamine use disorder and both current and legacy markers of HIV disease severity are associated with worse neurocognitive outcomes. There was no evidence of an HIV × M+ interaction across groups, but neurocognition was most impacted by HIV among those with polysubstance use disorder (M+C+). Better performance by C+ groups is consistent with findings from preclinical studies that cannabis use may protect against methamphetamine's deleterious effects.

Development and validation of a system for the prediction of challenging behaviors of people with autism spectrum disorder based on a smart wearable shirt: A mixed-methods design

Background

Most people with autism spectrum disorder (ASD) present at least one form of challenging behavior (CB), causing reduced life quality, social interactions, and community-based service inclusion.

Objectives

The current study had two objectives: (1) to assess the differences in physiological reaction to stressful stimuli between adults with and without high-functioning ASD; (2) to develop a system able to predict the incoming occurrence of a challenging behaviors (CBs) in real time and inform the caregiver that a CB is about to occur; (3) to evaluate the acceptability and usefulness of the developed system for users with ASD and their caregivers.

Methods

Comparison between physiological parameters will be conducted by enrolling two groups of 20 participants with and without ASD monitored while watching a relaxing and disturbing video. To understand the variations of the parameters that occur before the CB takes place, 10 participants with ASD who have aggressive or disruptive CBs will be monitored for 7 days. Then, an ML algorithm capable of predicting immediate CB occurrence based on physiological parameter variations is about to be developed. After developing the application-based algorithm, an efficient proof of concept (POC) will be carried out on one participant with ASD and CB. A focus group, including health professionals, will test the POC to identify the strengths and weaknesses of the developed system.

Results

Higher stress level is anticipated in the group of people with ASD looking at the disturbing video than in the typically developed peers. From the obtained data, the developed algorithm is used to predict CBs that are about to occur in the upcoming 1 min. A high level of satisfaction with the proposed technology and useful consideration for further developments are expected to emerge from the focus group.

Clinical trial registration

[https://clinicaltrials.gov/], identifier [NCT05340608].

Personality and Everyday Functioning in Older Adults With and Without HIV

In a cross-sectional multi-method study of older adults living with and without HIV (n = 202; 69.8% HIV seropositive), we tested associations between personality traits and everyday functioning, and whether these associations differed depending on HIV serostatus. We found that higher levels of conscientiousness and lower levels of neuroticism were associated with higher odds of being clinically independent (vs. dependent) in everyday functioning. These findings replicated across self- and clinician-reports and persisted above and beyond relevant covariates. We found no evidence of interactions between personality and HIV serostatus, suggesting that personality was equally important for everyday functioning regardless of HIV serostatus. Given the present findings and the knowledge that personality is dynamic and amenable to intervention, we discuss two different possible pathways for intervention meant to improve everyday functioning and quality of life among older adults with and without HIV: personality change and personalized medicine.

Evidence for neuropsychological health disparities in Black Americans with HIV disease

OBJECTIVE

Black Americans are at high risk for HIV disease and associated morbidity. The impact and clinical correlates of HIV-associated neurocognitive impairment among Black Americans is not fully understood. The current study uses a full factorial design to examine the independent and combined effects of race and HIV disease on neurocognitive functioning, including its associations with everyday functioning and clinical disease markers in Black and White persons with HIV (PWH).

METHOD

Participants included 40 Black PWH, 83 White PWH, 28 Black HIV- and 64 White HIV- individuals. Neurocognition was measured by raw sample-based z-scores from a clinical battery. Everyday functioning was assessed using self- and clinician-rated measures of cognitive symptoms and activities of daily living. HIV-associated neurocognitive disorders were also classified using demographically adjusted normative standards and the Frascati criteria.

RESULTS

We observed a significant three-way interaction between HIV, race, and domain on raw neurocognitive z-scores. This omnibus effect was driven by medium and large effect size decrements in processing speed and semantic memory, respectively, in Black PWH compared to other study groups. Black PWH also demonstrated higher frequencies of HIV-associated neurocognitive disorders as compared to White PWH. Unexpectedly, global neurocognitive performance was negatively related to everyday functioning impairments for White PWH, but not for Black PWH.

CONCLUSIONS

Systemic disadvantages for Black Americans may combine with HIV disease to compound some neurocognitive impairments in this under-served population. Prospective studies are needed to identify better ways to prevent, measure, diagnose, and manage HIV-associated neurocognitive disorders among Black Americans.

Assessment of executive functions as a measure of impairments in everyday functioning in persons with HIV

Persons with HIV can often present cognitive disorders such as those related to executive functioning, which could affect the daily life activities. The present study was designed to explore the predictive relationship between executive functions according to Miyake's model and the basic and instrumental skills of everyday functioning in a group of persons with HIV (PWH). Participants were recruited from outpatient treatment Hospital and assessed using a neuropsychological battery, a modified version of the Lawton and Brody basic and instrumental activities of daily life (ADL) scale and the Hospital Anxiety and Depression Scale (HADS). The results showed a low score in the executive function and significant relationship between executive functioning and the instrumental skills of the patients, with set-shifting being one of the most powerful predictors. The processes of executive functioning, particularly set-shifting, are related to the level of functioning in the skills required for independent living in the community, but not the skills of independent living in the home. This study seems to suggest the utility of assessing executive functions as a preventive measure for the development of dependencies in normal daily instrumental skills and as the focus of interdisciplinary interventions.

No differences in delay discounting between smokers with and without HIV

RATIONALE

People with HIV (PWH) smoke cigarettes at much higher rates than the general population and evidence-based cessation methods are less effective, putting PWH at greater risk for negative health outcomes. It is critical to identify the factors that underlie this health disparity. Delay discounting-the decline in the value of a reward when it is delayed-may explain this disparity.

OBJECTIVES

This study aimed to (1) compare delay discounting between adult smokers with HIV and without HIV and (2) evaluate whether acute smoking abstinence disproportionately increases delay discounting among smokers with HIV.

METHODS

This sub-study was part of a larger study (NCT03169101) examining predictors of smoking cessation outcomes among smokers with HIV (n = 34) and smokers without HIV (n = 46) at two counterbalanced laboratory sessions (once smoking-as-usual and once following 24-h biochemically confirmed abstinence) then again, after 8 weeks of smoking cessation treatment.

RESULTS

There were no significant differences in delay discounting rates between HIV status groups (p = 0.49) or within-subject abstinence effects (p = 0.70). However, smokers without HIV exhibited a significant increase in delay discounting following smoking cessation treatment compared to baseline (p = 0.02), whereas the change among smokers with HIV did not reach statistical significance (p = 0.09).

CONCLUSIONS

These findings do not support differences in delay discounting as a reason for the lower success rates of HIV+ smokers at quitting. Although delay discounting may not explain the disparity in smoking rates between people with and without HIV, future work should focus on additional correlates of higher smoking rates and lower quit rates among people with HIV.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Bidirectional Associations among Nicotine and Tobacco Smoke, NeuroHIV, and Antiretroviral Therapy

People living with HIV (PLWH) in the antiretroviral therapy (ART) era may lose more life-years to tobacco use than to HIV. Yet, smoking rates are more than twice as high among PLWH than the general population, contributing not just to mortality but to other adverse health outcomes, including neurocognitive deficits (neuroHIV). There is growing evidence that synergy with chronic inflammation and immune dysregulation that persists despite ART may be one mechanism by which tobacco smoking contributes to neuroHIV. This review will summarize the differential effects of nicotine vs tobacco smoking on inflammation in addition to the effects of tobacco smoke components on HIV disease progression. We will also discuss biomarkers of inflammation via neuroimaging as well as biomarkers of nicotine dependence (e.g., nicotine metabolite ratio). Tobacco smoking and nicotine may impact ART drug metabolism and conversely, certain ARTs may impact nicotine metabolism. Thus, we will review these bidirectional relationships and how they may contribute to neuroHIV and other adverse outcomes. We will also discuss the effects of tobacco use on the interaction between peripheral organs (lungs, heart, kidney) and subsequent CNS function in the context of HIV. Lastly, given the dramatic rise in the use of electronic nicotine delivery systems, we will discuss the implications of vaping on these processes. Despite the growing recognition of the importance of addressing tobacco use among PLWH, more research is necessary at both the preclinical and clinical level to disentangle the potentially synergistic effects of tobacco use, nicotine, HIV, cognition and immune dysregulation, as well as identify optimal approaches to reduce tobacco use. Graphical Abstract Proposed model of the relationships among HIV, ART, smoking, inflammation, and neurocognition. Solid lines represent relationships supported by evidence. Dashed lines represent relationships for which there is not enough evidence to make a conclusion. (a) HIV infection produces elevated levels of inflammation even among virally suppressed individuals. (b) HIV is associated with deficits in cognition function. (c) Smoking rates are higher among PLWH, compared to the general population. (d) The nicotine metabolite ratio (NMR) is associated with smoking behavior. (e) HIV and tobacco use are both associated with higher rates of psychiatric comorbidities, such as depression, and elevated levels of chronic stress. These factors may represent other mechanisms linking HIV and tobacco use. (f) The relationship between nicotine, tobacco smoking, and inflammation is complex, but it is well-established that smoking induces inflammation; the evidence for nicotine as anti-inflammatory is supported in some studies, but not others. (g) The relationship between tobacco use and neurocognition may differ for the effects of nicotine (acute nicotine use may have beneficial effects) vs. tobacco smoking (chronic use may impair cognition). (h) Elevated levels of inflammation may be associated with deficits in cognition. (i) PLWH may metabolize nicotine faster than those without HIV; the mechanism is not yet known and the finding needs validation in larger samples. We also hypothesize that if HIV-infection increases nicotine metabolism, then we should observe an attenuation effect once ART is initiated. (j) It is possible that the increase in NMR is due to ART effects on CYP2A6. (k) We hypothesize that faster nicotine metabolism may result in higher levels of inflammation since nicotine has anti-inflammatory properties.

Reduced intrinsic excitability of CA1 pyramidal neurons in human immunodeficiency virus (HIV) transgenic rats

The hippocampus is involved in key neuronal circuits that underlie cognition, memory, and anxiety, and it is increasingly recognized as a vulnerable structure that contributes to the pathogenesis of HIV-associated neurocognitive disorder (HAND). However, the mechanisms responsible for hippocampal dysfunction in neuroHIV remain unknown. The present study used HIV transgenic (Tg) rats and patch-clamp electrophysiological techniques to study the effects of the chronic low-level expression of HIV proteins on hippocampal CA1 pyramidal neurons. The dorsal and ventral areas of the hippocampus are involved in different neurocircuits and thus were evaluated separately. We found a significant decrease in the intrinsic excitability of CA1 neurons in the dorsal hippocampus in HIV Tg rats by comparing neuronal spiking induced by current step injections and by dynamic clamp to simulate neuronal spiking activity. The decrease in excitability in the dorsal hippocampus was accompanied by a higher rate of excitatory postsynaptic currents (EPSCs), whereas CA1 pyramidal neurons in the ventral hippocampus in HIV Tg rats had higher EPSC amplitudes. We also observed a reduction of hyperpolarization-activated nonspecific cationic current (Ih) in both the dorsal and ventral hippocampus. Neurotoxic HIV proteins have been shown to increase neuronal excitation. The lower excitability of CA1 pyramidal neurons that was observed herein may represent maladaptive homeostatic plasticity that seeks to stabilize baseline neuronal firing activity but may disrupt neural network function and contribute to HIV-associated neuropsychological disorders, such as HAND and depression.

Operationalizing and evaluating the Frascati criteria for functional decline in diagnosing HIV-associated neurocognitive disorders in adults

The Frascati criteria for HIV-associated neurocognitive disorders (HAND; Antinori et al. 2007) outlines a classification scheme for functional decline that-despite being over a decade old-has not heretofore been examined systematically. Participants included 307 HIV+ and 183 HIV- participants who completed self-report, clinician-rated, and performance-based measures of functional status, along with neurocognitive, psychiatric, and medical/laboratory assessments. Using the Frascati criteria, we classified participants with (1) no functional declines, (2) mild functional declines, or (3) major functional declines. A multivariable logistic regression showed that HIV serostatus was associated with higher rates of major (33.2 vs. 13.7%) but not mild (38.8 vs. 31.7%) Frascati-defined functional decline. Within the HIV+ group, individuals with global neurocognitive impairment and affective disorders were at highest risk of Frascati-defined functional decline. Findings provide some empirical support for the sensitivity and validity of the Frascati criteria for functional declines in the context of HAND. Future work is needed to determine the reliability, stability, cross-cultural validity, and downstream health-related consequences of the Frascati-defined functional classifications.

Frailty in Comorbid HIV and Lifetime Methamphetamine Use Disorder: Associations with Neurocognitive and Everyday Functioning

HIV and methamphetamine (MA) use disorder are commonly comorbid and individually associated with adverse health consequences, including frailty; however, less is known about the combined effects of both conditions. The current cross-sectional study examined how HIV and lifetime MA use disorder relate to frailty and explored associations between frailty and relevant clinical outcomes (i.e., neurocognitive and everyday functioning). Participants were categorized into three groups based on HIV status and lifetime MA diagnosis: HIV+/MA+ (n = 43), HIV+/MA- (n = 75), and HIV-/MA- (n = 92). A frailty index score (representing proportion of accumulated multisystem deficits) was calculated from 27 medical and psychiatric deficits. Multiple regression was used to examine frailty index score by HIV/MA group. Additional multiple regression models examined the interaction between frailty and HIV/MA group on cognitive and everyday functioning. Comorbid HIV+/MA+ participants had higher frailty index scores than both HIV-/MA- (b = -0.13, p < .001) and HIV+/MA- participants (b = -0.06, p = .007). Additional models linked higher frailty index score to worse global neurocognition (b = -17.6, p = .018) and greater likelihood of everyday functioning dependence (odds ratio = 1.56, p = .021). Although these relationships did not significantly differ by HIV/MA status, group-stratified analyses showed that associations of frailty with neurocognitive and everyday functioning were strongest among the HIV+/MA+ group. Multimodal public health interventions aimed at reducing frailty may help to decrease the likelihood of neurocognitive and everyday functioning problems. Current findings additionally lay groundwork for future longitudinal research examining whether frailty predicts onset of neurocognitive and functional decline in individuals with comorbid HIV and MA use disorder.

Conceptualizing and Assessing Everyday Functioning in the Context of HIV-Associated Neurocognitive Disorders

Combination antiretroviral therapy has reduced the rates of severe HIV-associated neurocognitive disorders (HAND), but the prevalence of milder forms of HAND that can affect everyday functioning remains high. As HIV-infected adults approach near-normal life expectancies, they may become increasingly susceptible to declines in everyday functioning secondary to a variety of physical and mental factors, including HAND. Although impairments in everyday functioning are a hallmark of HAND diagnoses and can adversely influence quality of life, there are no gold standard measures of this fundamentally important and complex construct. This chapter provides a brief review of the various self-report, clinician-rated, and performance-based methods by which everyday functioning is measured in the setting of HIV disease, including global activities of daily living and specific domains of medication adherence, financial management, automobile driving, and vocational functioning.

Grit and Ambition are Associated with Better Neurocognitive and Everyday Functioning Among Adults Living with HIV

Grit and ambition are psychological factors that may protect neurocognitive function among persons living with HIV (PLWH). We examined associations between grit, ambition, premorbid verbal intellectual function, and current neurocognitive and everyday functioning among PLWH and persons without HIV (HIV-). 120 PLWH and 94 HIV- adults completed the Grit Scale (includes total score and consistency of interests and perseverance of effort subscales), ambition scale, and a comprehensive neurobehavioral battery. PLWH had lower grit scores than HIV- adults. The two groups did not differ on ambition. No relationship was observed between grit and cognition among HIV- adults. Among PLWH, however, higher perseverance of effort and more ambition was related to better global neurocognitive functioning, and higher grit, but not ambition, was related to independence in daily functioning. Longitudinal studies are needed to elucidate these relationships over time and examine whether grit or ambition have protective effects on cognitive outcomes among PLWH.

Structural connectome differences in HIV infection: brain network segregation associated with nadir CD4 cell count

This study investigated structural brain organization using diffusion tensor imaging (DTI) in 35 HIV-positive and 35 HIV-negative individuals. We used global and nodal graph theory metrics to investigate whether HIV was associated with differences in brain network organization based on fractional anisotropy (FA) and mean diffusivity (MD). Participants also completed a comprehensive neuropsychological testing battery. For global network metrics, HIV-positive individuals displayed a lower FA clustering coefficient relative to HIV-negative individuals. For nodal network metrics, HIV-positive individuals had less MD nodal degree in the left thalamus. Within HIV-positive individuals, the FA global clustering coefficient was positively correlated with nadir CD4 cell count. Across the sample, cognitive performance was negatively correlated with characteristic path length and positively correlated with global efficiency for FA. These results suggest that, despite management with combination antiretroviral therapy, HIV infection is associated with altered structural brain network segregation and thalamic centrality and that low nadir CD4 cell count may be a risk factor. These graph theory metrics may serve as neural biomarkers to identify individuals at risk for HIV-related neurological complications.

Employment as a Social Determinant of Health: Exploring the Relationship Between Neurocognitive Function and Employment Status

Purpose:

To explore employment as a social determinant of health through examining the relationship between neurocognitive function and employment status.

Method:

The authors explored the causal relationship between employment status and neurocognitive function by conducting a systematic review of 15 longitudinal studies. The identified studies were conducted in Australia, Denmark, Norway, and the United States.

Results:

Five neurocognitive function domains were identified (i.e., complex attention, executive function, learning and memory, language, perceptual-motor function) across diagnosis (i.e., bipolar disorder, first-episode psychosis, human immunodeficiency virus, major depression, schizophrenia-spectrum disorders, traumatic brain injury). Unemployment was correlated with poorer attention, executive function, learning and memory, perceptual-motor function, and language. Employment was correlated with better attention, executive function, learning and memory, perceptual-motor function.

Conclusion:

The acknowledgment of the relationship between neurocognitive function and employment status can assist service providers in assessing and developing strategies to enhance and maintain employment outcomes. The assessment of neurocognitive function could be further explored by identifying standard measures and assessment timelines to assess the six domains across diagnosis. Vocational rehabilitation services could integrate cognitive interventions (cognitive rehabilitation, cognitive enhancement therapy, cognitive remediation) to explore the effect on neurocognitive function and employment outcomes. Further longitudinal research studies are needed, for both persons with disabilities and persons without disabilities, to elucidate the relationship between employment status and neurocognitive function.

Sonic Hedgehog mimetic prevents leukocyte infiltration into the CNS during acute HIV infection

Infiltration of infected leukocytes culminates in establishment of a brain niche for Human Immunodeficiency Virus (HIV) during acute phase of infection, initiating an ongoing cascade of persistent viral replication and inflammation, that causes irreversible neuronal injury and HIV associated neurocognitive disease (HAND). In this study, humanized mice were treated with Smoothened Agonist (SAG), a Sonic Hedgehog (Shh) mimetic in order to fortify blood brain barrier (BBB) and dampen leukocyte extravasation into CNS during AHI. Results indicate that SAG treatment reduced viral burden in the CNS immediately after HIV transmission, but also conferred extended neuroprotection via increased BBB integrity (elevated levels of tight-junction protein, Claudin 5, and reduced S100B levels in periphery). These mice also showed healthier neurons with thick, uniform dendrites and reduced numbers of activated astrocytes. Additional in vitro experiments suggested SAG treatment was not associated with the establishment or reversal of latency in the target cells. Altogether, these findings validate neuroprotective role of Shh signaling and highlight the therapeutic potential of Shh mimetics against CNS complications associated with HIV infection. Further our results strongly demonstrate that pharmacological interventions to reduce leukocyte mobilization during early HIV infection, can provide prolonged neuroprotection, which might significantly delay the onset of HAND.

Clinical utility of the UCSD Performance-Based Skills Assessment-Brief (UPSA-B) in adults living with HIV: Associations with neuropsychological impairment and patient-reported everyday functioning difficulties

Objective

Requiring only 10–15 minutes to complete, the UCSD Performance-Based Skills Assessment (UPSA-B) has high clinical utility as a brief measure of functional capacity. This study aimed to validate the UPSA-B in adults living with HIV/AIDS (HIV+), and identify whether the UPSA-B can be used as an indicator of functional dependence in this population.

Method

One hundred and three HIV+ adults and 91 HIV- adults completed a comprehensive neuropsychological and neuromedical battery, including a self-report measure of functional status (IADL Dependence vs. IADL Independence), an objective measure of functional capacity (UPSA-B), and a self-report measure of mood states including a subscale related to cognitive difficulties (Profile of Mood States [POMS]-Confusion/Bewilderment subscale).

Results

HIV+ participants had significantly lower UPSA-B scores than their HIV- counterparts (p = 0.02), although this fell to a trend (p = 0.08) when including covariates. Among the HIV+ group, higher UPSA-B scores were related to better neuropsychological ability, but unrelated to self-reported functional independence. Conversely, UPSA-B scores were unrelated to participant-reported cognitive difficulties on the POMS Confusion/Bewilderment subscale. An ROC curve was generated to determine the optimal UPSA-B value for discriminating between normal neuropsychological functioning versus neuropsychological impairment, with results indicating an optimal cutoff of 79. The UPSA-B identified HIV+ persons with cognitive impairment with 70.9% accuracy.

Conclusions

The UPSA-B was able to differentiate neuropsychological impairment from no impairment among HIV+ participants and holds promise as a clinical screening tool in this population. However, indicators of functional disability among adults living with HIV is still not well understood and is likely multifactorial in nature. These data highlight the complex interplay between objective functional capacity, neurocognitive ability, subjective cognitive symptoms, and functional dependence.

Testing a Computerized Cognitive Training Protocol in Adults Aging With HIV-Associated Neurocognitive Disorders: Randomized Controlled Trial Rationale and Protocol

Background

HIV-associated neurocognitive disorders occur in nearly 50% of adults with HIV. Such disorders can interfere with everyday functioning such as driving and medication adherence. Therefore, cognitive interventions are needed to address such neurocognitive disorders as well as improve everyday functioning, especially as people age with HIV.

Objective

This article reports and discusses the overall rationale and development of speed of processing training, a computerized Internet cognitive training program, to improve this specific neurocognitive ability as well as everyday functioning and quality of life in adults aging with HIV. Although this protocol has been shown to improve speed of processing, everyday functioning, and quality of life in healthy, community-dwelling older adults in the advanced cognitive training in vital elderly (ACTIVE) study, its efficacy in adults aging with HIV has not been established. Nevertheless, such a cognitive intervention is particularly germane as 52%-59% of adults with HIV experience HIV-associated neurocognitive disorders (HAND), and both the frequency and severity of such disorders may increase with advancing age.

Methods

The description of this longitudinal randomized controlled trial covers the following: (1) rationale for speed of processing training in this clinical population, (2) overview of overall study design, (3) eligibility criteria and HAND, (4) intervention dosage, (5) assessment battery, and (6) examination of biomarkers.

Results

The project was funded in April 2016 and enrolment is on-going. The first results are expected to be submitted for publication in 2020.

Conclusions

Similar novel cognitive intervention approaches are suggested as they may be of value to those with HAND and may utilize similar features of this current randomized controlled trial (RCT) protocol to examine their therapeutic efficacy.

Trial Registration

ClinicalTrials.gov NCT02758093; https://clinicaltrials.gov/ct2/show/NCT02758093 (Archived by Webcite at http://www.webcitation.org/6p8C5fBCX)

The nature and consequences of cognitive deficits among tobacco smokers with HIV: a comparison to tobacco smokers without HIV

HIV-infected smokers lose more years of life to tobacco-related disease than HIV. Since neurocognitive deficits are common among those with HIV and are associated with smoking persistence, these deficits may be a unique barrier to smoking cessation among HIV-infected smokers. Documenting unique differences in and correlates of cognition among HIV-infected smokers is a critical step towards developing a population-specific tobacco cessation treatment. We compared neurocognitive function between HIV-infected (n = 103) and HIV-uninfected smokers (n = 70), accounting for demographic and smoking-related variables. We also evaluated whether HIV-related health outcomes (e.g., CD4 count, viral load, depression ratings, quality of life [QoL]) and HAART adherence were associated with cognition. Participants completed neurocognitive tasks (N-back and Continuous Performance Task [CPT]) measuring working memory, attention, and processing speed, and intra-individual variability. Stepwise regression models were conducted and validated with resampling techniques. HIV-infected smokers performed worse than HIV-uninfected smokers on working memory, processing speed, and intra-individual variability (all p < 0.01). ROC analysis for the model including cognitive measures demonstrated 85% area under the curve, which indicates "good prediction" for distinguishing between HIV-infected and HIV-uninfected smokers. This was a significant improvement over the model including demographic and smoking-related variables only (p = 0.0003). Among HIV-infected smokers, neurocognitive performance was negatively associated with QoL and depression ratings. Smoking cessation interventions for HIV-infected smokers should consider cognitive neurorehabilitation as a potential strategy to decrease the likelihood of nicotine relapse and decrease tobacco-related morbidity in this population.

Cognitive function in early HIV infection

This study aimed to examine cognitive function in acute/early HIV infection over the subsequent 2 years. Fifty-six HIV+ subjects and 21 seronegative participants of the Chicago Early HIV Infection Study were evaluated using a comprehensive neuropsychological assessment at study enrollment and at 2-year follow-up. Cognitive performance measures were compared in the groups using t tests and mixed-effect models. Patterns of relationship with clinical measures were determined between cognitive function and clinical status markers using Spearman's correlations. At the initial timepoint, the HIV group demonstrated significantly weaker performance on measures of verbal memory, visual memory, psychomotor speed, motor speed, and executive function. A similar pattern was found when cognitive function was examined at follow-up and across both timepoints. The HIV subjects had generally weaker performance on psychomotor speed, executive function, motor speed, visual memory, and verbal memory. The rate of decline in cognitive function across the 2-year follow-up period did not differ between groups. Correlations between clinical status markers and cognitive function at both timepoints showed weaker performance associated with increased disease burden. Neurocognitive difficulty in chronic HIV infection may have very early onset and reflect consequences of initial brain viral invasion and neuroinflammation during the intense, uncontrolled viremia of acute HIV infection. Further characterization of the changes occurring in initial stages of infection and the risk and protective factors for cognitive function could inform new strategies for neuroprotection.

Problems screening for HAND among the educationally disadvantaged

Neurocognitive screeners are used to detect symptoms of HIV-Associated Neurocognitive Disorders (HAND). However, the degree to which education and socioeconomic status affect these screeners remains unclear. Neurocognitive screeners were administered to 187 socioeconomically disadvantaged HIV+ individuals upon entering treatment who had no other risk factors for HAND. The false positive rates were: 84% for the Montreal Cognitive Assessment, 59% for the International HIV Dementia Scale, and 28.3% for the Modified HIV Dementia Scale. Given these high false positive rates, the screeners may be more useful for establishing baseline functioning and sequential testing to detect deterioration.

Neurobehavioral Disturbances During Acute and Early HIV Infection

BACKGROUND AND OBJECTIVE

Acute and early human immunodeficiency virus infection (AEH) is accompanied by neuroinflammatory processes as well as impairment in neurocognitive and everyday functions, but little is known about the frequency and clinical correlates of the neurobehavioral disturbances during this period. We compared pre-seroconversion with current levels of apathy, disinhibition, and executive dysfunction; we also examined everyday function and HIV disease correlates of neuropsychiatric impairment in individuals with AEH.

METHODS

In this study, 34 individuals with AEH and 39 HIV-seronegative participants completed neuromedical and neuropsychological assessments, a structured psychiatric interview, and the apathy, disinhibition, and executive dysfunction subscales of the Frontal Systems Behavioral Scale.

RESULTS

Independent of any substance use and mood disorders, the AEH group had significantly higher levels of current apathy and executive dysfunction than the controls, but not greater disinhibition. Retrospective ratings of pre-seroconversion levels of apathy, disinhibition, and executive dysfunction were all higher in the AEH group than the controls. After seroconversion, the AEH cohort had increases in current apathy and executive dysfunction, but not disinhibition. In the AEH cohort, higher current global neurobehavioral dysfunction was significantly associated with lower nadir CD4 counts, slowed information processing speed, and more everyday function problems.

CONCLUSIONS

These data suggest that individuals who have recently acquired HIV experienced higher-than-normal premorbid levels of neurobehavioral disturbance. Apathy and executive dysfunction are exacerbated during AEH, particularly in association with lower CD4 counts.

Effects of HIV and Methamphetamine on Brain and Behavior: Evidence from Human Studies and Animal Models

Methamphetamine (Meth) use is frequent among HIV-infected persons. Combined HIV and Meth insults may exacerbate neural injury in vulnerable neuroanatomic structures or circuitries in the brain, leading to increased behavioral disturbance and cognitive impairment. While acute and chronic effects of Meth in humans and animal models have been studied for decades, the neurobehavioral effects of Meth in the context of HIV infection are much less explored. In-depth understanding of the scope of neurobehavioral phenotypes and mechanisms in HIV/Meth intersection is needed. The present report summarizes published research findings, as well as unpublished data, in humans and animal models with regard to neurobehavioral disturbance, neuroimaging, and neuropathology, and in vitro experimental systems, with an emphasis on findings emerging from the National Institute on Drug Abuse (NIDA) funded Translational Methamphetamine AIDS Research Center (TMARC). Results from human studies and animal (primarily HIV-1 gp120 transgenic mouse) models thus far suggest that combined HIV and Meth insults increase the likelihood of neural injury in the brain. The neurobehavioral effects include cognitive impairment and increased tendencies toward impaired behavioral inhibition and social cognition. These impairments are relevant to behaviors that affect personal and social risks, e.g. worse medication adherence, riskier behaviors, and greater likelihood of HIV transmission. The underlying mechanisms may include electrochemical changes in neuronal circuitries, injury to white matter microstructures, synaptodendritic damage, and selective neuronal loss. Utilization of research methodologies that are valid across species is instrumental in generating new knowledge with clinical translational value.

Apathy is associated with lower mental and physical quality of life in persons infected with HIV

HIV infection is associated with lower health-related quality of life (HRQoL), which is influenced by immunovirological factors, negative affect, neurocognitive impairment, and functional dependence. Although apathy is a common neuropsychiatric sequela of HIV infection, emerging findings regarding its unique role in lower HRQoL have been mixed. The present study was guided by Wilson and Cleary's (1995), model in examining the association between apathy and physical and mental HRQoL in 80 HIV+ individuals who completed a neuromedical examination, neuropsychological assessment, structured psychiatric interview, and a series of questionnaires including the SF-36. Apathy was measured using a composite of the apathy subscale of the Frontal Systems Behavioral Scale and the vigor-activation subscale of the Profile of Mood States. Independent of major depressive disorder, neurocognitive impairment, functional status, and current CD4 count, apathy was strongly associated with HRQoL. Specifically, apathy and CD4 count were significant predictors of physical HRQoL, whereas apathy and depression were the only predictors of mental HRQoL. All told, these findings suggest that apathy plays a unique role in HRQoL and support the importance of assessing and managing apathy in an effort to maximize health outcomes among individuals with HIV disease.

Aging with HIV-1 Infection: Motor Functions, Cognition, and Attention--A Comparison with Parkinson's Disease

Recent advances in highly active anti-retroviral therapy (HAART) in their various combinations have dramatically increased the life expectancies of HIV-infected persons. People diagnosed with HIV are living beyond the age of 50 but are experiencing the cumulative effects of HIV infection and aging on brain function. In HIV-infected aging individuals, the potential synergy between immunosenescence and HIV viral loads increases susceptibility to HIV-related brain injury and functional brain network degradation similar to that seen in Parkinson's disease (PD), the second most common neurodegenerative disorder in the aging population. Although there are clear diagnostic differences in the primary pathology of both diseases, i.e., death of dopamine-generating cells in the substantia nigra in PD and neuroinflammation in HIV, neurotoxicity to dopaminergic terminals in the basal ganglia (BG) has been implied in the pathogenesis of HIV and neuroinflammation in the pathogenesis of PD. Similar to PD, HIV infection affects structures of the BG, which are part of interconnected circuits including mesocorticolimbic pathways linking brainstem nuclei to BG and cortices subserving attention, cognitive control, and motor functions. The present review discusses the combined effects of aging and neuroinflammation in HIV individuals on cognition and motor function in comparison with age-related neurodegenerative processes in PD. Despite the many challenges, some HIV patients manage to age successfully, most likely by redistribution of neural network resources to enhance function, as occurs in healthy elderly; such compensation could be curtailed by emerging PD.

The HIV-1 transgenic rat model of neuroHIV

Despite the ability of current combination anti-retroviral therapy (cART) to limit the progression of HIV-1 to AIDS, HIV-positive individuals continue to experience neuroHIV in the form of HIV-associated neurological disorders (HAND), which can range from subtle to substantial neurocognitive impairment. NeuroHIV may also influence substance use, abuse, and dependence in HIV-positive individuals. Because of the nature of the virus, variables such as mental health co-morbidities make it difficult to study the interaction between HIV and substance abuse in human populations. Several rodent models have been developed in an attempt to study the transmission and pathogenesis of the HIV-1 virus. The HIV-1 transgenic (HIV-1Tg) rat is a reliable model of neuroHIV because it mimics the condition of HIV-infected patients on cART. Research using this model supports the hypothesis that the presence of HIV-1 viral proteins in the central nervous system increases the sensitivity and susceptibility of HIV-positive individuals to substance abuse.

Independent effects of HIV infection and cocaine dependence on neurocognitive impairment in a community sample living in the southern United States

BACKGROUND

Prior studies have established that methamphetamine and HIV can have additive deleterious effects on neurocognitive functioning, but there has been relatively little research on other stimulants like cocaine. This study investigated the effects of cocaine and HIV on neurocognitive impairment in a large, well-characterized sample.

METHODS

The sample included 193 adults across four groups: HIV-positive cocaine users (n = 48), HIV-negative cocaine users (n = 53), HIV-positive non-drug users (n = 60), and HIV-negative non-drug users (n = 32). Cocaine users met criteria for lifetime dependence and had past-month cocaine use. A comprehensive battery assessed substance abuse and neurocognitive functioning.

RESULTS

Participants were mostly male (66%) and African-American (85%), with a mean age of 46.09 years. The rate of global impairment was 33%, with no significant main effects across groups on likelihood of impairment. There were main effects for cocaine on processing speed and executive functioning, with cocaine users having greater impairment (F = 9.33 and F = 4.22, respectively), and for HIV on attention, with HIV-infected persons having greater impairment (F = 5.55). There was an interaction effect for executive functioning, with the three patient groups having greater impairment than controls (F = 5.05). Nonparametric analyses revealed significant additive impairment in the presence of both HIV and cocaine for processing speed.

CONCLUSIONS

While cocaine does not appear to increase vulnerability to global HIV-associated neurocognitive impairment, it does have independent adverse effects on executive functioning and processing speed. Given prior evidence that domain-specific deficits predict real-world impairments, our results may help explain the poorer behavioral and functional outcomes observed in HIV-infected cocaine users.

Habitual prospective memory in HIV disease

OBJECTIVE

HIV-associated neurocognitive disorders (HAND) are associated with deficits in prospective memory (PM). However, most PM research in HIV has used single-event tasks as opposed to habitual PM paradigms, which may be more relevant to clinical populations for whom many health-care behaviors must be performed both frequently and routinely.

METHOD

For the current study, we examined habitual PM and its associations with real-world functioning outcomes in 36 HIV+ individuals with HAND (HAND+), 70 HIV+ individuals without HAND (HAND-), and 115 HIV- individuals. The ongoing task consisted of 24 1-min Stroop trial blocks in which the emotive and cognitive load was manipulated. The habitual PM task required participants to press the spacebar once per block, but only after 20 s had elapsed.

RESULTS

A series of MANOVAs covarying for relevant clinicodemographic factors revealed a main effect of study group on habitual PM, such that the HAND+ cohort made significantly more repetition errors than the HIV- and HAND- groups, particularly during early trial blocks. There was no main effect of ongoing task demands, nor was there an interaction between HAND group and task demands. Within the entire HIV+ sample, poorer habitual PM was associated with deficits in learning and dysfunction in real-world outcomes, including medication nonadherence and failures on a naturalistic health-care task.

CONCLUSION

Findings indicate that HAND may be associated with deficient internal source monitoring or temporal discrimination for habitual PM output that may play a critical role in real-world functioning, including HIV disease management.

Reduced neural specificity in middle-aged HIV+ women in the absence of behavioral deficits

In the post combination antiretroviral therapy (cART) era, the prevalence of mild forms of HIV-associated neurocognitive disorders (HAND) in individuals with HIV-infection remains high. There is a pressing need to find biomarkers that can aid clinical assessment of HAND, especially in those with mild or no neurocognitive symptoms. Here we hypothesized that a reduction in neural specificity, or the specificity of neuronal tuning, could serve as a potential biomarker of asymptomatic HAND. To directly test this hypothesis, we applied two advanced fMRI techniques to examine the difference in neural specificity between middle-aged HIV+ women and age-matched negative controls, with a focus on the fusiform face area (FFA), a critical region in face processing. Face discrimination performance was assessed outside of the scanner. While the behavioral performance of face discrimination was comparable between the two groups, a reduced neural specificity in the FFA of HIV-positive women was revealed by a novel fMRI analysis technique, local regional heterogeneity analysis, or H_corr, as well as an established technique, fMRI-rapid adaptation. In contrast, conventional fMRI techniques were insensitive to these early changes. These results suggest that, prior to the onset of detectable behavioral deficits, significant neuronal dysfunctions are already present in HIV+ individuals, and these early neuronal dysfunctions can be detected and assessed via neural specificity, which, in combining with the novel H_corr technique, has a strong potential to serve as a biomarker of asymptomatic HAND and other neurodegenerative diseases.

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We investigate early neuronal dysfunctions in cognitively normal HIV+ women.

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Conventional fMRI technique reveals normal neural activity in the FFA of HIV+ women.

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fMRI-adaptation reveals a decrease in neural specificity in the FFA of HIV+ women.

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H_corr, a novel fMRI technique, confirms the fMRI-adaptation results

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H_corr-estimated neural specificity might serve as a biomarker of asymptomatic HAND

Epigenetic alterations in the brain associated with HIV-1 infection and methamphetamine dependence

HIV involvement of the CNS continues to be a significant problem despite successful use of combination antiretroviral therapy (cART). Drugs of abuse can act in concert with HIV proteins to damage glia and neurons, worsening the neurotoxicity caused by HIV alone. Methamphetamine (METH) is a highly addictive psychostimulant drug, abuse of which has reached epidemic proportions and is associated with high-risk sexual behavior, increased HIV transmission, and development of drug resistance. HIV infection and METH dependence can have synergistic pathological effects, with preferential involvement of frontostriatal circuits. At the molecular level, epigenetic alterations have been reported for both HIV-1 infection and drug abuse, but the neuropathological pathways triggered by their combined effects are less known. We investigated epigenetic changes in the brain associated with HIV and METH. We analyzed postmortem frontal cortex tissue from 27 HIV seropositive individuals, 13 of which had a history of METH dependence, in comparison to 14 cases who never used METH. We detected changes in the expression of DNMT1, at mRNA and protein levels, that resulted in the increase of global DNA methylation. Genome-wide profiling of DNA methylation in a subset of cases, showed differential methylation on genes related to neurodegeneration; dopamine metabolism and transport; and oxidative phosphorylation. We provide evidence for the synergy of HIV and METH dependence on the patterns of DNA methylation on the host brain, which results in a distinctive landscape for the comorbid condition. Importantly, we identified new epigenetic targets that might aid in understanding the aggravated neurodegenerative, cognitive, motor and behavioral symptoms observed in persons living with HIV and addictions.

Detrimental impact of remote methamphetamine dependence on neurocognitive and everyday functioning in older but not younger HIV+ adults: evidence for a legacy effect?

Prior studies examining the combined adverse effects of HIV and methamphetamine (MA) on the central nervous system (CNS) have focused on younger to middle-aged adults with recent MA use diagnoses. Aging, HIV, and MA all converge on prefrontal and temporolimbic neural systems and confer independent risk for neurocognitive and functional decline. Thus, this study sought to determine the residual impact of a remote history of MA dependence on neurocognitive and real-world outcomes in older people living with HIV (PLWH). Participants included 116 older (≥50 years) and 94 younger (<40 years) adults classified into one of six study groups based on HIV serostatus (HIV+/HIV-) and lifetime histories of MA dependence (MA+/MA-): older HIV-MA- (n = 36), older HIV+MA- (n = 49), older HIV+MA+ (n = 31), younger HIV-MA- (n = 27), younger HIV+MA- (n = 33), and younger HIV+MA+ (n = 34). No participant-met criteria for current MA use disorders and histories of MA dependence were remote in both the older (average of nearly 9 years prior to evaluation) and younger (average of over 2 years prior to evaluation) HIV+MA+ groups. Findings revealed that a remote history of MA dependence exerts a significant detrimental impact on specific aspects of neurocognitive performance (e.g., memory) and a broad range of real-world functioning outcomes (e.g., employment) among older, but not younger PLWH. These results suggest that MA-associated neurotoxicity may have significant "legacy" effects on both neurocognitive and functional outcomes to which older PLWH are particularly vulnerable.