The Neuropsychology of HIV/AIDS in Older Adults

Neuropsychological tests associated with symptomatic HIV-associated neurocognitive disorder (HAND) in a cohort of older adults in Tanzania

OBJECTIVE

Human immunodeficiency virus (HIV)-associated neurocognitive disorder (HAND) prevalence is expected to increase in East Africa as treatment coverage increases, survival improves, and this population ages. This study aimed to better understand the current cognitive phenotype of this newly emergent population of older combination antiretroviral therapy (cART)-treated people living with HIV (PLWH), in which current screening measures lack accuracy. This will facilitate the refinement of HAND cognitive screening tools for this setting.

METHOD

This is a secondary analysis of 253 PLWH aged ≥50 years receiving standard government HIV clinic follow-up in Kilimanjaro, Tanzania. They were evaluated with a detailed locally normed low-literacy neuropsychological battery annually on three occasions and a consensus panel diagnosis of HAND by Frascati criteria based on clinical evaluation and collateral history.

RESULTS

Tests of verbal learning and memory, categorical verbal fluency, visual memory, and visuoconstruction had an area under the receiver operating characteristic curve >0.7 for symptomatic HAND (s-HAND) (0.70-0.72; p < 0.001 for all tests). Tests of visual memory, verbal learning with delayed recall and recognition memory, psychomotor speed, language comprehension, and categorical verbal fluency were independently associated with s-HAND in a logistic mixed effects model (p < 0.01 for all). Neuropsychological impairments varied by educational background.

CONCLUSIONS

A broad range of cognitive domains are affected in older, well-controlled, East African PLWH, including those not captured in widely used screening measures. It is possible that educational background affects the observed cognitive impairments in this setting. Future screening measures for similar populations should consider assessment of visual memory, verbal learning, language comprehension, and executive and motor function.

Evaluation of Event-Related Potentials in Somatic Diseases - Systematic Review

Many somatic illnesses (e.g. hypertension, diabetes, pulmonary and cardiac diseases, hepatitis C, kidney and heart failure, HIV infection, Sjogren's disease) may impact central nervous system functions resulting in emotional, sensory, cognitive or even personality impairments. Event-related potential (ERP) methodology allows for monitoring neurocognitive processes and thus can provide a valuable window into these cognitive processes that are influenced, or brought about, by somatic disorders. The current review aims to present published studies on the relationships between somatic illness and brain function as assessed with ERP methodology, with the goal to discuss where this field of study is right now and suggest future directions.

Health literacy mediates the effects of educational attainment on online pharmacy navigation skills in older adults with HIV disease

ObjectiveThe Internet serves an increasingly critical role in health behaviors for older adults with chronic medical conditions. Guided by theories of health behaviors and literacy, this study examined whether the relationship between educational attainment and online pharmacy skills in older persons with HIV disease (PWH) is mediated by health literacy. Design: Participants included 98 PWH age 50 and older who completed the Test of Online Pharmacy Skills (TOPS), which required them to navigate an experimenter-controlled online pharmacy to perform several naturalistic tasks (e.g., refill an existing prescription). Participants also completed the Medication-Management Test-Revised (MMT-R). Results: Mediation analyses revealed a significant indirect effect of education on both online pharmacy accuracy and MMT-R, which was fully mediated by health literacy. In contrast, there was no direct or indirect effect of education on online pharmacy speed when health literacy was included as a mediator. Conclusion: Health literacy plays an important role in the relationship between years of education attained and the ability of older PWH to successfully navigate online pharmacy tasks and manage their medications. Future studies might examine whether interventions to improve electronic health literacy among older PWH who have lower educational attainment have beneficial effects on online health behaviors.

The global burden of cognitive impairment in people with HIV

OBJECTIVE

While life expectancies of people with HIV (PWH) have increased through the successes of antiretroviral treatment, cognitive impairment remains a pressing concern. Prevalence estimates vary worldwide as different definitions for cognitive impairment are used and resource availability differs across geographical settings. We aim to explore this heterogeneity and estimate the global cognitive impairment burden in PWH.

DESIGN

Systematic literature review and meta-analysis.

METHODS

We searched PubMed, Embase, SCOPUS, and Web of Science for studies reporting on cognitive impairment prevalence in PWH. Nine factors were investigated for their potential association with the prevalence using a univariate meta-analysis and a meta-regression: assessment method, geographical region, country income, exclusion criteria, study quality, age, sex, publication year, and sample size.

RESULTS

The literature search identified 8539 records, of which 225 were included. The adjusted prevalence was significantly lower in males than females. Across 44 countries, 12 assessment methods were used; the HIV-associated neurocognitive disorder/Frascati criteria, known for high false-positive rates, was employed in 44.4% of studies. The pooled cognitive impairment prevalence estimate in PWH, including asymptomatic cases, was 39.6% (95% confidence interval: 37.2-42.1%; range: 7-87%). The meta-regression explained 13.3% of between-study variation, with substantial residual heterogeneity ( I2  = 97.7%).

CONCLUSION

Lack of data from more than 70% of the world's countries, cohorts being unselected for symptoms in most research studies, and limitations of the HIV-associated neurocognitive disorder/Frascati criteria restrict the ability to accurately determine the global burden of cognitive impairment in PWH. More studies in low-resource settings and a standardized approach to assessing cognitive impairment, bridging research and clinical realms, are needed.

Inhibitory Neurotransmission Is Sex-Dependently Affected by Tat Expression in Transgenic Mice and Suppressed by the Fatty Acid Amide Hydrolase Enzyme Inhibitor PF3845 via Cannabinoid Type-1 Receptor Mechanisms

(1) Background. The endocannabinoid (eCB) system, which regulates physiological and cognitive processes, presents a promising therapeutic target for treating HIV-associated neurocognitive disorders (HAND). Here we examine whether upregulating eCB tone has potential protective effects against HIV-1 Tat (a key HIV transactivator of transcription) protein-induced alterations in synaptic activity. (2) Methods. Whole-cell patch-clamp recordings were performed to assess inhibitory GABAergic neurotransmission in prefrontal cortex slices of Tat transgenic male and female mice, in the presence and absence of the fatty acid amide hydrolase (FAAH) enzyme inhibitor PF3845. Western blot and mass spectrometry analyses assessed alterations of cannabinoid receptor and enzyme protein expression as well as endogenous ligands, respectively, to determine the impact of Tat exposure on the eCB system. (3) Results. GABAergic activity was significantly altered upon Tat exposure based on sex, whereas the effectiveness of PF3845 to suppress GABAergic activity in Tat transgenic mice was not altered by Tat or sex and involved CB1R-related mechanisms that depended on calcium signaling. Additionally, our data indicated sex-dependent changes for AEA and related non-eCB lipids based on Tat induction. (4) Conclusion. Results highlight sex- and/or Tat-dependent alterations of GABAergic activity and eCB signaling in the prefrontal cortex of Tat transgenic mice and further increase our understanding about the role of FAAH inhibition in neuroHIV.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Effects of Age, Level of Education and HIV Status on Cognitive Performance in West African Older Adults: The West Africa IeDEA Cohort Collaboration

An in-depth understanding of the impact of aging, cognitive reserve, and HIV status on cognitive function is needed in older West African adults. Ninety-nine HIV-negative and 334 HIV-positive adults aged ≥ 50 years were enrolled in three clinics (Senegal and Côte d'Ivoire) participating in the IeDEA West Africa collaboration. All subjects underwent the Free and Cued Selective Reminding Test (FCSRT) and the Isaacs Set Test (IST). Age (both linear and quadratic), education level, and HIV status effects on Z-scores were assessed using multivariate linear regression models. Interactions between HIV status and age or educational level were tested. In the present cohort of older West African adults, the role of age and educational level on episodic memory and verbal fluency was observed without revealing an interaction between HIV status and age effect. As age had quadratic effects, older HIV-positive adults should not be considered as a unique group irrespective of their age. Low-educated HIV-positive patients had the lowest verbal fluency performance compared to others. Further studies are needed to duplicate these results. In clinical settings, screening and adapted programs focusing on improving cognition in those patients are needed.

Racial differences in health and cognition as a function of HIV among older adults

The present study investigated the contribution of health risk factors (using the Charlson Comorbidity Index [CCI]) on cognitive outcomes in a sample of 380 HIV-positive (HIV+; n = 221) and HIV-seronegative (HIV-; n = 159) African American and European American adults aged 50+.

Participants were recruited from HIV clinics and community advertisements. HIV status was confirmed by serological testing. Self-report and chart history review was used to gather information about medical ssscomorbidities. The Charlson Comorbidity Index (CCI) was used to create a comorbidity score. Participants were administered a brief cognitive test battery.

As expected, health risks were greater among those with HIV. There was a HIV × Race interaction on CCI scores, such that in the HIV + group, European Americans had significantly higher CCI scores (M = 3.74; SD = 2.1) than African American HIV + participants (M = 2.70; SD = 1.9). However, in the HIV - group, African Americans had significantly higher CCI scores (M = 2.20; SD = 1.1) than HIV - European American participants (M = 1.80; SD = 1.2). Also, consistent with hypotheses, across the entire sample CCI score was significantly associated with global cognition (β = -.24, p = .02).

Study results underscore the importance of considering HIV serostatus in studies examining racial disparities in health, and how multiple medical risks relate to cognitive outcomes. Neuropsychologists evaluating patients living with HIV should consider how the presence of multiple medical comorbidities may contribute to the course of cognitive decline as people age.

Association of HIV infection and cognitive impairment in older adults: A meta-analysis

OBJECTIVE

To synthesize evidence on the association between human immunodeficiency virus (HIV) infection and cognitive impairment in older adults.

DESIGN

Meta-analysis.

PARTICIPANTS

Adults aged 50 years or older.

METHODS

In this systematic literature review and meta-analysis, we searched PubMed, Scopus, Embase, and APA/PsycNet for studies published before July 21, 2020, that assessed the association between HIV-infection and cognitive impairment. We calculated pooled odds ratios (ORs) of cognitive impairment for people living with HIV (PLWH) and 95 % confidence intervals (CIs) using random-effect models and calculated pooled mean difference (MD) for major cognitive domains between PLWH and HIV-uninfected adults. We assessed risk of bias using the Newcastle-Ottawa scale.

RESULTS

Of the 4432 studies identified, 21 cross-sectional studies were eligible for the meta-analysis, including 15 examining global cognitive impairment. The meta-analysis showed that older PLWH were more likely to be cognitively impaired than HIV-uninfected controls (OR = 2.44, 95 % CI = [1.69, 3.53], number of estimates (k) = 15, I2 = 71 %). This higher likelihood was shown in studies from high income countries (OR = 2.63, 95 % CI = [1.76, 3.94], k = 12, I2 = 55 %), but not from upper-middle income countries (OR = 1.96, 95 % CI = [0.26, 14.68], k = 3, I2 = 91 %). PLWH had lower scores than HIV-uninfected adults in 5 out of 7 major cognitive domains, including executive function (MD = -0.42, 95 % CI = [-0.72, -0.11], k = 5, I2 = 32 %), processing speed (MD = -0.33, 95 % CI = [-0.59, -0.08], k = 6, I2 = 16 %), verbal (MD=-0.29, 95 % CI = [-0.48, -0.10], k = 6, I2 = 0%), recall (MD = -0.24, 95 % CI = [-0.38, -0.10], k = 6, I2 = 0%) and motor/psychomotor (MD = -0.38, 95 % CI = [-0.59, -0.16], k = 5, I2 = 31 %) performance.

CONCLUSIONS/IMPLICATIONS

Our meta-analysis provides empirical evidence that HIV infection is associated with an increased risk of cognitive impairment among older adults, especially in cognitive domains of executive function, processing speed, verbal, recall, and motor/psychomotor.

Prevalence and 1-year incidence of HIV-associated neurocognitive disorder (HAND) in adults aged ≥50 years attending standard HIV clinical care in Kilimanjaro, Tanzania

OBJECTIVES

HIV-associated neurocognitive disorders (HANDs) are prevalent in older people living with HIV (PLWH) worldwide. HAND prevalence and incidence studies of the newly emergent population of combination antiretroviral therapy (cART)-treated older PLWH in sub-Saharan Africa are currently lacking. We aimed to estimate HAND prevalence and incidence using robust measures in stable, cART-treated older adults under long-term follow-up in Tanzania and report cognitive comorbidities.

DESIGN

Longitudinal study.

PARTICIPANTS

A systematic sample of consenting HIV-positive adults aged ≥50 years attending routine clinical care at an HIV Care and Treatment Centre during March-May 2016 and followed up March-May 2017.

MEASUREMENTS

HAND by consensus panel Frascati criteria based on detailed locally normed low-literacy neuropsychological battery, structured neuropsychiatric clinical assessment, and collateral history. Demographic and etiological factors by self-report and clinical records.

RESULTS

In this cohort (n = 253, 72.3% female, median age 57), HAND prevalence was 47.0% (95% CI 40.9-53.2, n = 119) despite well-managed HIV disease (Mn CD4 516 (98-1719), 95.5% on cART). Of these, 64 (25.3%) were asymptomatic neurocognitive impairment, 46 (18.2%) mild neurocognitive disorder, and 9 (3.6%) HIV-associated dementia. One-year incidence was high (37.2%, 95% CI 25.9 to 51.8), but some reversibility (17.6%, 95% CI 10.0-28.6 n = 16) was observed.

CONCLUSIONS

HAND appear highly prevalent in older PLWH in this setting, where demographic profile differs markedly to high-income cohorts, and comorbidities are frequent. Incidence and reversibility also appear high. Future studies should focus on etiologies and potentially reversible factors in this setting.

Cognitive ageing is premature among a community sample of optimally treated people living with HIV

OBJECTIVES

Evidence of premature cognitive ageing amongst people living with HIV (PLHIV) remains controversial due to previous research limitations including underpowered studies, samples with suboptimal antiretroviral access, varying rate of virological control, high rate of AIDS, over-representation of non-community samples, and inclusion of inappropriate controls. The current study addresses these limitations, while also considering mental health and non-HIV comorbidity burden to determine whether PLHIV showed premature cognitive ageing compared with closely comparable HIV-negative controls.

METHODS

This study enrolled 254 PLHIV [92% on antiretroviral therapy; 84% with HIV RNA < 50 copies/mL; 15% with AIDS) and 72 HIV-negative gay and bisexual men [mean (SD) age = 49 (10.2) years] from a single primary care clinic in Sydney, Australia. Neurocognitive function was evaluated with the Cogstate Computerized Battery (CCB) at baseline and 6 months after. Linear mixed-effects (LME) models examined main and interaction effects of HIV status and chronological age on the CCB demographically uncorrected global neurocognitive z-score (GZS), adjusting for repeated testing, and then adjusting sequentially for HIV disease markers, mental health and comorbidities.

RESULTS

HIV status and age interacted with a lower GZS (β = -0.43, P < 0.05). Higher level of anxiety symptoms (β = -0.11, P < 0.01), historical AIDS (β = -0.12, P < 0.05) and historical HIV brain involvement (β = -0.12, P < 0.05) were associated with lower GZS.

CONCLUSIONS

We found a robust medium-sized premature ageing effect on cognition in a community sample with optimal HIV care. Our study supports routine screening of cognitive and mental health among PLHIV aged ≥ 50 years.

Is There Any Evidence of Premature, Accentuated and Accelerated Aging Effects on Neurocognition in People Living with HIV? A Systematic Review

Despite evidence of premature, accentuated and accelerated aging for some age-related conditions such as cardiovascular diseases in people living with HIV (PLHIV), the evidence for these abnormal patterns of aging on neurocognition remains unclear. Further, no systematic review has been dedicated to this issue. Using PRISMA guidelines, we searched standard databases (PubMed, EMBASE, CINAHL and PsycINFO). Articles were included if they analyzed and reported the effect of age on neurocognition among PLHIV as one of their major findings, if they were conducted in the combination anti-retroviral therapy era (after 1996) and published in a peer-reviewed journal in English. Quality appraisal was conducted using the Joanna Briggs Institute (JBI) appraisal tools. To systematically target the abnormal patterns of neurocognitive aging, we define premature cognitive aging as significant interaction effect of HIV status and age on cross-sectional neurocognitive test performance covering both the normal and abnormal performance range; accentuated cognitive aging as significant interaction effect of HIV status and age on cross-sectional neurocognitive impairment (NCI) rate, thus covering the abnormal performance range only; accelerated cognitive aging as significant interaction effect of HIV status and age on longitudinal neurocognitive test performance or incidence of NCI. Because these definitions require an age-comparable HIV-negative (HIV-) control group, when no controls were included, we determined the range of the age effect on neurocognitive test performance or NCI among PLHIV. A total of 37 studies originating from the US (26), UK (2), Italy (2), Poland (2), China (2), Japan (1), Australia (1), and Brazil (1) were included. Six studies were longitudinal and 14 included HIV- controls. The quality appraisal showed that 12/37 studies neither used an age-matched HIV- controls nor used demographically corrected cognitive scores. A meta-analysis was not possible because study methods and choice of neurocognitive measurement methods and outcomes were heterogeneous imposing a narrative synthesis. In studies with an HIV- control sample, premature neurocognitive aging was found in 45% of the cross-sectional analyses (9/20), while accelerated neurocognitive aging was found in 75% of the longitudinal analyses (3/4). There was no evidence for accentuated aging, but this was tested only in two studies. In studies without an HIV- control sample, the age effect was always present but wide (NCI OR = 1.18-4.8). While large sample size (> 500) was associated with abnormal patterns of cognitive aging, most of the studies were under powered. Other study characteristics such as longitudinal study design and higher proportion of older participants were also associated with the findings of abnormal cognitive aging. There is some support for premature and accelerated cognitive aging among PLHIV in the existing literature especially among large and longitudinal studies and those with higher proportion of older samples. Future HIV and cognitive aging studies need to harmonize neuropsychological measurement methods and outcomes and use a large sample from collaborative multi-sites to generate more robust evidences.

Mini-review: The therapeutic role of cannabinoids in neuroHIV

In the era of combined antiretroviral therapy (cART), human immunodeficiency virus type 1 (HIV-1) is considered a chronic disease with an inflammatory component that specifically targets the brain and causes a high prevalence of HIV-1-associated neurocognitive disorders (HAND). The endocannabinoid (eCB) system has attracted interest as a target for treatment of neurodegenerative disorders, due to the potential anti-inflammatory and neuroprotective properties of cannabinoids, including its potential therapeutic use in HIV-1 neuropathogenesis. In this review, we summarize what is currently known about the structural and functional changes of the eCB system under conditions of HAND. This will be followed by summarizing the current clinical and preclinical findings on the effects of cannabis use and cannabinoids in the context of HIV-1 infection, with specifically focusing on viral load, cognition, inflammation, and neuroprotection. Lastly, we present some potential future directions to better understand the involvement of the eCB system and the role that cannabis use and cannabinoids play in neuroHIV.

Screening for HIV-Associated Neurocognitive Disorder (HAND) in Adults Aged 50 and Over Attending a Government HIV Clinic in Kilimanjaro, Tanzania. Comparison of the International HIV Dementia Scale (IHDS) and IDEA Six Item Dementia Screen

Validated screening tools for HIV-associated neurocognitive disorders (HAND) are lacking for the newly emergent ageing population of people living with HIV (PLWH) in sub-Saharan Africa (SSA). We aimed to validate and compare diagnostic accuracy of two cognitive screening tools, the International HIV dementia scale (IHDS), and the Identification and Interventions for Dementia in Elderly Africans (IDEA) screen, for identification of HAND in older PLWH in Tanzania. A systematic sample of 253 PLWH aged ≥ 50 attending a Government clinic in Tanzania were screened with the IHDS and IDEA. HAND were diagnosed by consensus American Academy of Neurology (AAN) criteria based on detailed clinical neuropsychological assessment. Strict blinding was maintained between screening and clinical evaluation. Both tools had limited diagnostic accuracy for HAND (area under the receiver operating characteristic (AUROC) curve 0.639–0.667 IHDS, 0.647–0.713 IDEA), which was highly-prevalent (47.0%). Accurate HAND screening tools for older PLWH in SSA are needed.

Computerized Cognitive Rehabilitation Training for Ugandan Seniors Living with HIV: A Validation Study

The feasibility, acceptability and preliminary efficacy of computerized cognitive rehabilitation therapy (CCRT) for mitigating neurocognitive decline was evaluated in African adults ≥50 years old. Eighty-one Ugandans with (n = 40) and without (n = 41) chronic human immunodeficiency viruses (HIV) were allocated CCRT—i.e., 20–45-min cognitive training sessions with culturally adapted video games delivered via Captain’s Log Software, or standard of care (SOC). Pre and post (i.e., 8-weeks later) intervention performance based neurocognitive tests, quality of life (QOL) and frailty related phenotype (FRP) were determined in all respondents. Multivariable linear regression estimated CCRT- vs. SOC-related differences (β) in neurocognitive batteries, QOL and FRP. Effect sizes (ES) for estimated β were calculated. CCRT protocol was completed by 92.8% of persons allocated to it. Regardless of HIV status, CCRT was associated with higher performance in learning tests than SOC—interference list (β = 1.00, 95%CI: (0.02, 1.98); ES = 0.43) and delayed recall (β = 1.04, 95%CI: (0.06, 2.02); ES = 0.47). CCRT effect on verbal fluency was clinically important (ES = 0.38), but statistical significance was not reached (β = 1.25, 95%CI: (−0.09, 2.58)). Among HIV-positive adults, clinically important post-CCRT improvements were noted for immediate recall (ES = 0.69), working memory (ES = 0.51), verbal fluency (ES = 0.51), and timed gait (ES = −0.44) tasks. Among HIV-negative adults, CCRT resulted in moderate post-intervention improvement in learning tests (ES = 0.45) and large decline in FRP (ES = −0.71), without a positive effect on simple attention and visuomotor coordination tasks. CCRT intervention is feasible among older Ugandan adults with potential benefit for learning and verbal fluency tests regardless of HIV status and lowering FRP in HIV-negative older adults.

Psycho-behavioral factors associated with neurocognitive performance among people living with HIV on antiretroviral therapy in Accra, Ghana

BACKGROUND

It is estimated that almost half of all people living with HIV have some form of neurocognitive impairment, but few studies have looked at the risk of neurocognitive impairment and its associated factors in Ghana, due in part to limited resources for such testing.

OBJECTIVES

To examine neurocognitive performance in a group of Ghanaians living with HIV and possible factors that contribute to their performance.

METHODS

One hundred and four patients were assessed using a selection of brief non-invasive neuropsychological assessments as well as the International HIV Dementia Scale. Psycho-behavioural factors (alcohol use, depression, and medication adherence) as well as demographic characteristics and functional daily activities were assessed to determine their association with neurocognitive performance, using linear regression and receiver operating characteristic analyses.

RESULT

About 48% of the participants met the criteria for risk of neurocognitive impairment. Age, education, and symptoms of depression were found to be significantly associated with the risk of impairment.

CONCLUSION

Some people living with HIV showed risk of neurocognitive impairment, which was significantly associated with education, age and depressive symptoms. It is therefore important to consider routine neurocognitive screening in HIV management to recognize any risks for early interventions.

Inhibitory Control Deficits Associated with Upregulation of CB1R in the HIV-1 Tat Transgenic Mouse Model of Hand

In the era of combined antiretroviral therapy, HIV-1 infected individuals are living longer lives; however, longevity is met with an increasing number of HIV-1 associated neurocognitive disorders (HAND) diagnoses. The transactivator of transcription (Tat) is known to mediate the neurotoxic effects in HAND by acting directly on neurons and also indirectly via its actions on glia. The Go/No-Go (GNG) task was used to examine HAND in the Tat transgenic mouse model. The GNG task involves subjects discriminating between two stimuli sets in order to determine whether or not to inhibit a previously trained response. Data reveal inhibitory control deficits in female Tat(+) mice (p = .048) and an upregulation of cannabinoid type 1 receptors (CB₁R) in the infralimbic (IL) cortex in the same female Tat(+) group (p < .05). A significant negative correlation was noted between inhibitory control and IL CB₁R expression (r = −.543, p = .045), with CB₁R expression predicting 30% of the variance of inhibitory control (R² = .295, p = .045). Furthermore, there was a significant increase in spontaneous excitatory postsynaptic current (sEPSC) frequencies in Tat(+) compared to Tat(−) mice (p = .008, across sexes). The increase in sEPSC frequency was significantly attenuated by bath application of PF3845, a fatty acid amide hydrolase (FAAH) enzyme inhibitor (p < .001). Overall, the GNG task is a viable measure to assess inhibitory control deficits in Tat transgenic mice and results suggest a potential therapeutic treatment for the observed deficits with drugs which modulate endocannabinoid enzyme activity.

Graphical Abstract

Aberrant brain dynamics in neuroHIV: Evidence from magnetoencephalographic (MEG) imaging

Magnetoencephalography (MEG) is a noninvasive, silent, and totally passive neurophysiological imaging method with excellent temporal resolution (~1ms) and good spatial precision (~3-5mm). While MEG studies of neuroHIV remain relatively rare, the number of studies per year has sharply increased recently and this trend will likely continue into the foreseeable future. The current in-depth review focuses on the studies that have been conducted to date, which include investigations of somatosensory and visual modalities, resting-state, as well as motor control and higher-level functions such as working memory and visual attention. The review begins with an introduction to the principles and methods of MEG, and then transitions to a review of each of the empirical studies that have been conducted to date, separated by sensory modality for the basic studies and cognitive domain for the higher-level investigations. As such, this review attempts to be exhaustive in its coverage of empirical MEG studies of neuroHIV. Across studies major themes emerge including aberrant neural oscillatory activity in HIV-infected adults, both in primary sensory regions of the brain and higher-order executive regions. Many studies have also connected the amplitude of neural oscillations to behavioral and/or neuropsychological function in the study population, making a vital connection to performance and improving the veracity of the findings. One conspicuous emerging area is the use of MEG to distinguish cognitively-impaired from unimpaired HIV-infected adults, with major success reported and future studies sure to come. The review concludes with a summary of findings and suggested focus areas for future studies.

Evaluating the Feasibility and Impact of a Yoga Intervention on Cognition, Physical Function, Physical Activity, and Affective Outcomes in People Living With HIV: Protocol for a Randomized Pilot Trial

Background

Despite lower mortality rates due to combination antiretroviral therapy, people living with HIV (PLWH) are grappling with increasingly complex health issues, including cognitive impairments in areas such as memory, attention, processing speed, and motor function. Yoga has been shown to be an effective form of exercise and mindfulness-based stress reduction for many clinical populations. However, no randomized trials have evaluated the impact of yoga on cognitive and physical function among PLWH.

Objective

The aim of this pilot randomized trial was to determine the feasibility of a yoga intervention to lay the groundwork for a full-scale, multisite, community-based trial for PLWH. Specific objectives are to (1) assess the feasibility of study protocol and procedures, (2) compare cognition in the yoga group with the usual care control group after 12 weeks of the intervention in PLWH, and (3) compare the effects of the 12-week yoga intervention versus control on balance, walking speed, physical activity, mental health, medication adherence, and quality of life among PLWH.

Methods

We propose a pilot randomized trial with 2 parallel groups (yoga versus control). We will recruit 25 PLWH (>35 years) from community and health organizations in Halifax, Canada. After baseline assessment with blinded assessors, participants will be randomly assigned to the yoga or control group, using a random computer generator. Participants in the yoga group will engage in supervised 60-min group-based yoga sessions 3 times a week for 12 weeks at a yoga studio. Participants in the control group will maintain their current physical activity levels throughout the study.

Results

As per the Consolidated Standards of Reporting Trials extension for pilot studies, means of all outcomes, mean change, and 95% CIs will be calculated for each group separately. Two-tailed independent t tests and Fisher exact tests will be used to compare groups at baseline. We will analyze quantitative postintervention questionnaire responses using Chi-square tests, and open-ended responses will be analyzed thematically. Intention-to-treat and per-protocol analyses will be used to analyze secondary variables. Changes in outcome variables will be examined between groups and within groups. Effect sizes will be reported for each outcome. A priori adherence and satisfaction criteria will be met if participants attend >70% of the yoga sessions and if >70% of the participants are satisfied with the intervention as determined by a postparticipation questionnaire. Study enrollment began in January 2018, with results expected for October 2019.

Conclusions

This pilot randomized trial will be the first to investigate the feasibility and effect of a yoga intervention on cognitive and physical outcomes among PLWH. This work will inform the feasibility of further investigations in terms of capacity building, participant recruitment and retention, and assessment and intervention protocols.

Trial Registration

ClinicalTrials.gov NCT03071562; https://clinicaltrials.gov/ct2/show/NCT03071562 (Archived by WebCite at http://www.webcitation.org/785sfhWkw)

International Registered Report Identifier (IRRID)

DERR1-10.2196/13818

The current understanding of overlap between characteristics of HIV-associated neurocognitive disorders and Alzheimer's disease

The advent of effective antiretroviral medications (ARVs) has led to an aging of the HIV population with approximately 50% of people with HIV (PWH) being over the age of 50 years. Neurocognitive complications, typically known as HIV-associated neurocognitive disorders (HAND), persist in the era of ARVs and, in addition to risk of HAND, older PWH are also at risk for age-associated, neurodegenerative disorders including Alzheimer's disease (AD). It has been postulated that risk for AD may be greater among PWH due to potential compounding effects of HIV and aging on mechanisms of neural insult. We are now faced with the challenge of disentangling AD from HAND, which has important prognostic and treatment implications given the more rapidly debilitating trajectory of AD. Herein, we review the evidence to date demonstrating both parallels and differences in the profiles of HAND and AD. We specifically address similarities and difference of AD and HAND as it relates to (1) neuropsychological profiles (cross-sectional/longitudinal), (2) AD-associated neuropathological features as evidenced from neuropathological, cerebrospinal fluid and neuroimaging assessments, (3) biological mechanisms underlying cortical amyloid deposition, (4) parallels in mechanisms of neural insult, and (5) common risk factors. Our current understanding of the similarities and dissimilarities of AD and HAND should be further delineated and leveraged in the development of differential diagnostic methods that will allow for the early identification of AD and more suitable and effective treatment interventions among graying PWH.

The Aging Brain With HIV Infection: Effects of Alcoholism or Hepatitis C Comorbidity

As successfully treated individuals with Human Immunodeficiency Virus (HIV)-infected age, cognitive and health challenges of normal aging ensue, burdened by HIV, treatment side effects, and high prevalence comorbidities, notably, Alcohol Use Disorders (AUD) and Hepatitis C virus (HCV) infection. In 2013, people over 55 years old accounted for 26% of the estimated number of people living with HIV (~1.2 million). The aging brain is increasingly vulnerable to endogenous and exogenous insult which, coupled with HIV infection and comorbid risk factors, can lead to additive or synergistic effects on cognitive and motor function. This paper reviews the literature on neuropsychological and in vivo Magnetic Resonance Imaging (MRI) evaluation of the aging HIV brain, while also considering the effects of comorbidity for AUD and HCV.

Effect of age and level of education on neurocognitive impairment in HIV positive Zambian adults

OBJECTIVE

Older age and lower education levels are known to be associated with worse neurocognitive (NC) performance in healthy adults, and individuals with HIV infection may experience accelerated brain/cognition aging. However, higher education may possibly protect against HIV-associated neurocognitive disorders (HAND). The aim of the current cross-sectional study was to assess the effect of age and education in an HIV-1 clade C infected adult population in urban Zambia.

METHOD

Demographically corrected Zambian norms on a neuropsychological (NP) test battery were used to correct for normal age and education effects. The study assessed 286 HIV positive (+) males (37.1%) and females (62.9%) with a mean age of 41.35 (SD = 8.56) and mean years of education = 10.16 (SD = 2.18). A comprehensive NP test battery was used to assess cognitive domains frequently affected by HIV: attention/working memory, learning/and delayed recall, executive function, verbal fluency, processing speed, verbal and visual episodic memory, and fine motor skills.

RESULTS

In younger HIV+ Zambians, higher education evidenced protective effects against NC impairments overall, and for the specific domains of executive functions, learning and speed of information processing. Impairment scores did not support accelerated overall brain aging although the restricted age range and relative youth of our total sample may have precluded detection of such tendencies.

CONCLUSIONS

The present study raises the need to investigate factors that could be implicated in the poor neurocognitive performance among the younger, less educated HIV+ individuals in Zambia. (PsycINFO Database Record

Longitudinal intra-individual variability in neuropsychological performance relates to white matter changes in HIV

OBJECTIVES

Recent studies suggest that intraindividual variability (IIV) of neuropsychological performance may be sensitive to HIV-associated neurologic compromise. IIV may be particularly dependent upon the integrity of frontal-subcortical systems, and therefore may be a meaningful phenotype in HIV. We examined the relationship between change in IIV and white matter integrity among HIV seropositive (HIV+) and HIV seronegative (HIV-) individuals.

METHOD

The sample consisted of 38 HIV+ participants and 26 HIV- control participants who underwent neuroimaging and a neuropsychological evaluation at baseline and at 2-year follow-up evaluation.

RESULTS

Among HIV+ participants, increases in IIV (greater dispersion) were related to lower fractional anisotropy (FA) values in the anterior thalamic radiations (ATR) and the superior longitudinal fasciculus (SLF). Changes in mean-level global cognitive functioning were not significantly related to white matter integrity. Additionally, there was a significant Group × IIV interaction effect in the SLF demonstrating that the relationship between IIV and white matter integrity was specific to HIV.

CONCLUSIONS

Overall, findings suggest that IIV may be more sensitive, relative to mean-level global cognitive functioning, in the detection of neurologic compromise among HIV+ individuals. (PsycINFO Database Record

Exercise and cognitive function in people living with HIV: a scoping review

BACKGROUND

Since the advent of antiretrovirals, people with HIV are living longer and have improved quality of life. However, 30-60% of these individuals experience cognitive impairment. Fortunately, physical activity has emerged as a management strategy for cognitive impairment.

PURPOSE

To map the evidence on physical activity and cognition in HIV.

METHODS

We searched five databases using terms related to physical activity and HIV. Two authors independently reviewed titles and abstracts for studies that addressed physical activity/exercise and cognition in people with HIV. Authors reviewed full texts to identify articles that met our inclusion criteria. One author extracted the data, then we collated the results and summarized the characteristics of included studies.

RESULTS

Sixteen studies from high-income countries were included; eight were interventional (five randomized controlled trials and three pre-post single group observational studies) and eight were non-interventional studies. The interventional studies included aerobic, resistive, and Tai Chi exercise for 8 weeks to 12 months in duration. Two of eight interventional studies found exercise to benefit self-reported cognition. All eight non-interventional studies showed a positive relationship between physical activity and cognitive function.

CONCLUSIONS

Results of this study suggest that physical activity may preserve or improve cognition in people living with HIV. Implications for Rehabilitation Physical activity may play a role in preserving or improving cognition in the human immunodeficiency virus population. Exercise should be prescribed for people with human immunodeficiency virus based on the stage of infection. Rehabilitation professionals should follow current exercise guidelines when prescribing exercise for people living with human immunodeficiency virus.

HIV-associated neurocognitive disorder

Human immunodeficiency virus (HIV)-associated neurocognitive disorder (HAND) affects roughly half the HIV-positive population. The symptoms of cognitive slowing, poor concentration, and memory problems can impact on everyday life. Its diagnosis is validated where possible by identifying deficits in two cognitive domains on neuropsychologic testing in patients either with or without symptoms. Corroborating evidence may be found on imaging, blood tests, and cerebrospinal fluid analysis, though sensitive and specific biomarkers are currently lacking. The introduction of combined antiretroviral therapy in the 1990s has generated a therapeutic paradox whereby the number of severe cases of HAND has fallen, yet milder forms continue to rise in prevalence. New emphasis has been placed on identifying the cause of apparent ongoing HIV infection and inflammation of the central nervous system (CNS) in the face of durable systemic viral suppression, and how this equates to the neuronal dysfunction underlying HAND. The interaction with aging and comorbidities is becoming increasingly common as the HIV-positive population enters older adulthood, with neurodegenerative, metabolic, and vascular causes of cognitive impairment combining and probably accelerating in the context of chronic HIV infection. Therapies targeted to the CNS, but without neurotoxic side-effects, are being investigated to attempt to reduce the likelihood of developing, and improving, HAND.

Diagnostic utility of the HIV dementia scale and the international HIV dementia scale in screening for HIV-associated neurocognitive disorders among Spanish-speaking adults

Given that neurocognitive impairment is a frequent complication of HIV-1 infection in Spanish-speaking adults, the limited number of studies assessing HIV-associated neurocognitive disorders (HAND) in this population raises serious clinical concern. In addition to being appropriately translated, instruments need to be modified, normed, and validated accordingly. The purpose of the current study was to examine the diagnostic utility of the HIV Dementia Scale (HDS) and International HIV Dementia Scale (IHDS) to screen for HAND in Spanish-speaking adults living with HIV infection. Participants were classified as either HAND (N = 47) or No-HAND (N = 53) after completing a comprehensive neuropsychological evaluation. Receiver operating characteristic analyses found the HDS (AUC = .706) was more sensitive to detecting HAND than the IHDS (AUC = .600). Optimal cutoff scores were 9.5 for the HDS (PPV = 65.2%, NPV = 71.4%) and 9.0 for the IHDS (PPV = 59.4%, NPV = 59.1%). Canonical Correlation Analysis found the HDS converged with attention and executive functioning. Findings suggest that while the IHDS may not be an appropriate screening instrument with this population, the HDS retains sufficient statistical validity and clinical utility to screen for HAND in Spanish-speaking adults as a time-efficient and cost-effective measure in clinical settings with limited resources.

Effect of transcranial direct current stimulation combined with cognitive training on cognitive functioning in older adults with HIV: A pilot study

The objective of this study was to examine combination speed of processing (SOP) cognitive remediation therapy (CRT) and transcranial direct stimulation (tDCS) as neurorehabilitation in older HIV+ adults. Thirty-three HIV+ adults aged 50+ completed neurocognitive testing and were randomized to either active (n = 17) or sham (n = 16) tDCS. Both conditions received 10 1-hour sessions of SOP CRT, with either active or sham tDCS for the first 20 minutes. Participants then completed a posttest assessment. Repeated measures analysis of variance examining Time X Condition showed small-to-medium effects in the expected direction for an executive (d = 0.36), and SOP measure (d = 0.49), while medium-to-large effects were observed for an executive/attention (d = 0.60) and oral reading measure (d = 0.75). The only statistically significant interaction was the oral reading measure. Small-to-medium and medium-to-large effects (ds = 0.32, 0.58) were found for two SOP measures in the opposite direction (sham group showing greater improvements). Further trials of CRT and tDCS in this population are needed, including larger samples and a nonactive control and tDCS only condition, as is determination of which parameters of each technique (e.g., tDCS montage, timing of tDCS, domain targeted in CRT, number of sessions) are most effective in improving cognitive outcomes, durability of training gains, and translation to everyday functioning.

Endocannabinoids exert CB1 receptor-mediated neuroprotective effects in models of neuronal damage induced by HIV-1 Tat protein

In the era of combined antiretroviral therapy (cART), human immunodeficiency virus type 1 (HIV-1) is considered a chronic disease that specifically targets the brain and causes HIV-1-associated neurocognitive disorders (HAND). Endocannabinoids (eCBs) elicit neuroprotective and anti-inflammatory actions in several central nervous system (CNS) disease models, but their effects in HAND remain unknown. HIV-1 does not infect neurons, but produces viral toxins, such as transactivator of transcription (Tat), that disrupt neuronal calcium equilibrium and give rise to synaptodendritic injuries and cell death, the former being highly correlated with HAND. Consequently, we tested whether the eCBs N-arachidonoylethanolamine (anandamide/AEA) and 2-arachidonoyl-glycerol (2-AG) offer neuroprotective actions in a neuronal culture model. Specifically, we examined the neuroprotective actions of these eCBs on Tat excitotoxicity in primary cultures of prefrontal cortex neurons (PFC), and whether cannabinoid receptors mediate this neuroprotection. Tat-induced excitotoxicity was reflected by increased intracellular calcium levels, synaptodendritic damage, neuronal excitability, and neuronal death. Further, upregulation of cannabinoid 1 receptor (CB₁R) protein levels was noted in the presence of HIV-1 Tat. The direct application of AEA and 2-AG reduced excitotoxic levels of intracellular calcium and promoted neuronal survival following Tat exposure, which was prevented by the CB₁R antagonist rimonabant, but not by the CB₂R antagonist AM630. Overall, our findings indicate that eCBs protect PFC neurons from Tat excitotoxicity in vitro via a CB₁R-related mechanism. Thus, the eCB system possesses promising targets for treatment of neurodegenerative disorders associated with HIV-1 infection.

Effect of ageing on neurocognitive function by stage of HIV infection: evidence from the Multicenter AIDS Cohort Study

BACKGROUND

The demographics of the HIV epidemic in the USA have shifted towards older age. We aimed to establish the relationship between the processes of ageing and HIV infection in neurocognitive impairment.

METHODS

With longitudinal data from the Multicenter AIDS Cohort Study, a long-term prospective cohort study of the natural and treated history of HIV infection among men who have sex with men in the USA, we examined the effect of ageing, HIV infection (by disease stage), and their interaction on five neurocognitive domains: information processing speed, executive function, episodic memory, working memory, and motor function. We controlled for duration of serostatus in a subanalysis, as well as comorbidities and other factors that affect cognition. Analyses were by linear mixed models for longitudinal data.

FINDINGS

5086 participants (47 886 visits) were included in the analytic sample (2278 HIV-seropositive participants contributed 20 477 visits and 2808 HIV-seronegative control participants contributed 27 409 visits). In an a-priori multivariate analysis with control variables including comorbidities and time since seroconversion, significant, direct negative effects of ageing were noted on all neurocognitive domains (p<0·0001 for all). Similar effects were noted for late-stage HIV disease progression on information processing speed (p=0·002), executive function (p<0·0001), motor function (p<0·0001), and working memory (p=0·001). Deleterious interaction effects were also noted in the domains of episodic memory (p=0·03) and motor function (p=0·02).

INTERPRETATION

A greater than expected effect of ageing on episodic memory and motor function with advanced stages of HIV infection suggests that these two domains are most susceptible to the progression of neurocognitive impairment caused by ageing in individuals with HIV. This deficit pattern suggests differential damage to the hippocampus and basal ganglia (specifically nigrostriatal pathways). Older individuals with HIV infection should be targeted for regular screening for HIV-associate neurocognitive disorder, particularly with tests referable to the episodic memory and motor domains.

FUNDING

National Institute of Mental Health.

Feedback on a Multimodal Cognitive Intervention for Adults Aging With HIV: A Focus Group Study

Nearly 50% of adult persons living with HIV (PLWH) experience HIV-associated neurocognitive disorder (HAND), which is associated with deteriorating brain health and cognitive functioning. Multimodal interventions that simultaneously improve physical activity, nutrition, and sleep hygiene may be of value for adult PLWH, especially as they age and become vulnerable to HAND. We used four focus groups of PLWH (N = 30; ages ≥ 50 years) to solicit feedback about Cognitive Prescriptions, a multimodal cognitive intervention. Lifestyle and health behaviors pertaining to Cognitive Prescriptions were assessed, including: (a) physical activity, (b) mental activity, (c) nutrition, (d) social engagement, (e) emotional health, (f) sleep hygiene, and (g) substance use. When presented a template of the intervention, participants expressed favorable opinions and remarked they would want to work with a clinician, paraprofessional, or peer to implement such a program into their own daily routines. From this, implications for practice and research are provided.

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)

Accelerated and accentuated neurocognitive aging in HIV infection

There is debate as to whether the neurocognitive changes associated with HIV infection represent an acceleration of the typical aging process or more simply reflect a greater accentuated risk for age-related declines. We aimed to determine whether accelerated neurocognitive aging is observable in a sample of older HIV-infected individuals compared to age-matched seronegatives and older old (i.e., aged ≥65) seronegative adults. Participants in a cross-sectional design included 48 HIV-seronegative (O-) and 40 HIV-positive (O+) participants between the ages of 50-65 (mean ages = 55 and 56, respectively) and 40 HIV-seronegative participants aged ≥65 (OO-; mean age = 74) who were comparable for other demographics. All participants were administered a brief neurocognitive battery of attention, episodic memory, speeded executive functions, and confrontation naming (i.e., Boston Naming Test). The O+ group performed more poorly than the O- group (i.e., accentuated aging), but not differently from the OO- on digit span and initial recall of a supraspan word list, consistent with an accelerating aging profile. However, the O+ group's performance was comparable to the O- group on all other neurocognitive tests (ps > 0.05). These data partially support a model of accelerated neurocognitive aging in HIV infection, which was observed in the domain of auditory verbal attention, but not in the areas of memory, language, or speeded executive functions. Future studies should examine whether HIV-infected adults over 65 evidence accelerated aging in downstream neurocognitive domains and subsequent everyday functioning outcomes.

Impairments in Component Processes of Executive Function and Episodic Memory in Alcoholism, HIV Infection, and HIV Infection with Alcoholism Comorbidity

BACKGROUND

Executive functioning and episodic memory impairment occur in HIV infection (HIV) and chronic alcoholism (ALC). Comorbidity of these conditions (HIV + ALC) is prevalent and heightens risk of vulnerability to separate and compounded deficits. Age and disease-related variables can also serve as mediators of cognitive impairment and should be considered, given the extended longevity of HIV-infected individuals in this era of improved pharmacological therapy.

METHODS

HIV, ALC, HIV + ALC, and normal controls (NC) were administered traditional and computerized tests of executive function and episodic memory. Test scores were expressed as age- and education-corrected Z-scores; selective tests were averaged to compute Executive Function and Episodic Memory Composite scores. Efficiency scores were calculated for tests with accuracy and response times.

RESULTS

HIV, ALC, and HIV + ALC had lower scores than NC on Executive Function and Episodic Memory Composites, with HIV + ALC even lower than ALC and HIV on the Episodic Memory Composite. Impairments in planning and free recall of visuospatial material were observed in ALC, whereas impairments in psychomotor speed, sequencing, narrative free recall, and pattern recognition were observed in HIV. Lower decision-making efficiency scores than NC occurred in all 3 clinical groups. In ALC, age and lifetime alcohol consumption were each unique predictors of Executive Function and Episodic Memory Composite scores. In HIV + ALC, age was a unique predictor of Episodic Memory Composite score.

CONCLUSIONS

Disease-specific and disease-overlapping patterns of impairment in HIV, ALC, and HIV + ALC have implications regarding brain systems disrupted by each disease and clinical ramifications regarding the complexities and compounded damping of cognitive functioning associated with dual diagnosis that may be exacerbated with aging.

Neuropsychological profiles of adults and older adults with HIV

The wider availability of highly active antiretroviral therapy has resulted in a concomitant increase in adults aging with HIV and the persistence of milder forms of neuropsychological impairment in this cohort. This study investigated the differences in neuropsychological functioning between a group of HIV+ adults and older adults and an HIV− matched control group. Participants from a semi-urban community clinic volunteered to participate in the study. The performance of 50 participants (33 HIV+ and 17 HIV−) who met the inclusion criteria were compared on the following measures: Dementia Rating Scale-2, the Stroop Color and Word Test, the Symbol Digits Modalities Test, and the Delis–Kaplan Executive Function System Trail Making Test. The results indicated that the HIV+ in comparison with the HIV− negative group had poorer performance profiles in global cognitive functioning, memory, executive functioning, visuoconstruction ability, psychomotor functioning, and processing speed. The findings suggest that further research in South Africa will contribute to a better understanding of the neuropsychological profiles of adults aging with HIV and inform intervention strategies specific to addressing the mental healthcare needs of this subgroup.

Behavioral and neuroimaging evidence for impaired executive function in "cognitively normal" older HIV-infected adults

The increased prevalence of HIV among adults >50 years underscores the importance of improving our understanding of mechanisms causing HIV-associated neurocognitive disorders (HAND). Identifying novel and noninvasive diagnostic predictors of HAND prior to clinical manifestation is critical to ultimately identifying means of preventing progression to symptomatic HAND. Here, using a task-switching paradigm, in which subjects were cued (unpredictably) to perform a face-gender or a word-semantic task on superimposed face and word images, we examined the behavioral and neural profile of impaired cognitive control in older HIV + adults (N = 14, 9 HIV+). Functional magnetic resonance imaging (fMRI) and behavioral data were acquired while subjects were performing the face-gender or word-semantic task. We found that, despite comparable performance in standard neuropsychology tests that are designed to probe executive deficits, HIV-infected participants were significantly slower than uninfected controls in adapting to change in task demand, and the behavioral impairments can be quantitatively related to difference in fMRI signal at the dorsal anterior cingulate cortex (ACC). Due to the limited sample size of this hypothesis-generating study, we should take caution with these findings and future studies with a large and better matched sample size are needed. However, these rather novel findings in this study have a few important implications: first, the prevalence of cognitive impairments in HIV+ older adults might be even higher than previously proposed; second, ACC (in particularly its dorsal region) might be one of the key regions underlying cognitive impairments (in particularly executive functions) in HIV; and third, it might be beneficial to adopt paradigms developed and validated in cognitive neuroscience to study HAND, as these techniques might be more sensitive to some aspects of HIV-associated neurocognitive impairments than standard neuropsychology tests.

Biomedical risk, psychosocial influences, and developmental outcomes: lessons from the pediatric HIV population in Africa

Sub-Saharan Africa is home to millions of HIV-affected children. These children are likely to experience multiple developmental delays. In this chapter, I present data highlighting compromised neurobehavioral, mental health, and scholastic outcomes for children affected by HIV. Furthermore, I discuss biomedical factors (e.g., disease severity and nutritional status) that may exacerbate the adverse effects of HIV on childhood outcomes. I also present evidence on how psychosocial risk factors such as poor maternal mental health, orphanhood, and poverty may aggravate the effects of HIV. The concluding section of the chapter highlights conceptual and methodological refinements in research on the impact of HIV on child development in Sub-Saharan Africa.

SL, Woods SP, Grant I, Jeste DV, Moore DJ. Physical Activity is Associated with Better Neurocognitive and Everyday Functioning Among Older Adults with HIV Disease

We examined the association between physical activity (PA), neurocognitive impairment (NCI), and instrumental activities of daily living (IADLs) among older HIV+ persons. One hundred older HIV+ adults completed the International Physical Activity Questionnaire, a neurocognitive battery, and IADL scale. Higher levels of moderate PA were associated with lower odds of NCI (p = 0.01), even when covariates were modeled. The association between moderate PA and NCI was driven by executive function (p = 0.04). Higher levels of moderate PA were also associated with lower odds of IADL Dependence (p = 0.03), although this fell to a trend (p = 0.08) when including covariates. Follow-up analysis showed those with both NCI and IADL Dependence had lower moderate PA than those with neither (p = 0.03). While these cross-sectional findings suggest PA is associated with better neurocognitive and everyday functioning in older HIV+ adults, longitudinal studies utilizing objective PA methods are needed to evaluate directionality and mechanisms.

Effects of HIV and combination antiretroviral therapy on cortico-striatal functional connectivity

OBJECTIVE

Determine whether HIV and combination antiretroviral therapy (cART) affect resting-state functional connectivity (rs-fc) between the striatum and the cortical regions.

METHODS

Forty-nine HIV-uninfected (HIV-) and 132 HIV-infected (HIV+) (65% receiving cART) patients underwent laboratory studies (current and nadir CD4 T-cell counts, and plasma HIV viral load), neuropsychological performance testing, and neuroimaging. Rs-fc, which examines the coordination of neural activity in distant brain regions, was used to investigate the cortico-striatal functional connections. The effect of cART was assessed comparing HIV+ individuals on cART (HIV+/cART+), and HIV+ individuals not currently receiving cART (HIV+/cART-). Relationships between laboratory tests, cognitive performance, and cART on subcortical-cortical rs-fc were assessed by an analysis of variance.

RESULTS

HIV+ individuals had lower cortico-striatal functional connectivity than HIV- controls, specifically between the striatum and the default mode network (P < 0.001) and ventral attention network (P < 0.001). HIV+/cART+ individuals had higher functional connectivity between the striatum, and default mode network (P = 0.02) and ventral attention network (P = 0.01), compared to the HIV+/cART- patients. Laboratory (current and nadir CD4 T-cell counts, plasma viral load) and neuropsychological performance was not correlated with cortico-striatal rs-fc.

CONCLUSIONS

HIV was associated with disrupted cortico-striatal networks, consistent with HIV's known impact on the subcortical areas. Interestingly, within certain networks, HIV+/cART+ individuals had similar rs-fc compared to HIV- controls, suggesting possible improvements in HIV-related neural dysfunction due to medications. Rs-fc may be a sensitive biomarker of neural insult and its recovery following cART. Additional studies may show rs-fc has utility in measuring acute inflammation caused by HIV.

Moving toward a holistic conceptual framework for understanding healthy aging among gay men

In the last four decades, we have witnessed vast and important transitions in the social, economic, political, and health contexts of the lived experiences of gay men in the United States. This dynamic period, as evidenced most prominently by the transition of the gay rights movement to a civil rights movement, has shifted the exploration of gay men's health from one focusing primarily on HIV/AIDS into a mainstream consideration of the overall health and wellbeing of gay men. Against this backdrop, aging gay men in the United States constitute a growing population, for whom further investigations of health states and health-related disparities are warranted. In order to advance our understanding of the health and wellbeing of aging gay men, we outline here a multilevel, ecosocial conceptual framework that integrates salient environmental, social, psychosocial, and sociodeomgraphic factors into sets of macro-, meso-, and micro-level constructs that can be applied to comprehensively study health states and health care utilization in older gay men.

The synergistic effects of HIV, diabetes, and aging on cognition: implications for practice and research

Thanks to highly active antiretroviral therapy, many people infected with HIV will likely live into old age. Although this is a welcome prognosis, new issues are emerging that may complicate the ability to successfully age in this clinical population. HIV and aging independently are related to cognitive impairments, so there are concerns that those aging with HIV may be more at risk of such cognitive impairments. Moreover, highly active antiretroviral therapy itself can create metabolic disorders, such as prediabetes and/or frank type 2 diabetes, which have also been linked to poorer cognitive functioning. Thus, concerns increase that, as people age with HIV and develop comorbid metabolic disorders that may lead to type 2 diabetes, they will be at triple risk of developing cognitive impairments that can impair everyday functioning and reduce quality of life. This article explores these issues and provides implications for practice and research.

Aging with HIV infection: a journey to the center of inflammAIDS, immunosenescence and neuroHIV

In the last years, a significant improvement in life expectancy of HIV+ patients has been observed in Western countries. The parallel increase in the mean age of these patients causes a parallel increase in the frequency of non-AIDS related complications (i.e., neurocognitive, cardiovascular, liver and kidney diseases, metabolic syndrome, osteoporosis, non-HIV associated cancers, among others), even when antiviral treatment is successful. Immune activation and persistent inflammation characterizes both HIV infection and physiological aging, and both conditions share common detrimental pathways that lead to early immunosenescence. Furthermore, HIV-associated neurocognitive disorders represent important consequences of the infection. The persistent systemic immune activation, the continuous migration of activated monocytes to the central nervous system and progressive patients' aging contribute to develop neuronal injuries, that are in turn linked to HIV-associated neurocognitive disorders, which can persist despite successful antiretroviral treatment.

Patterns of substance use among HIV-positive adults over 50: implications for treatment and medication adherence

BACKGROUND

The population of older adults living with HIV is increasing in the United States. Despite an increased focus on the health of HIV-positive older adults, knowledge about their substance use, a primary risk factor for HIV medication non-adherence, and the association between use, problems associated with use, and adherence behavior, is limited.

METHODS

Data were collected from 557 HIV-positive adults aged 50 and older in the New York City area via telephone interview. Participants reported the number of days in the past month on which they missed any doses of HIV medication as well as the number of days they used alcohol, marijuana, cocaine/crack, opiates, amyl nitrite (poppers), and other drugs. The severity of substance use associated problems was assessed using the DAST-10 and AUDIT-C.

RESULTS

The sample included gay/bisexual (40.4%) and heterosexual (28.1%) men as well as lesbian/bisexual (4.9%) and heterosexual (26.7%) women. Latent class analyses identified four distinct patterns of substance use: Exclusive Alcohol Use; Alcohol and Marijuana; Alcohol and Cocaine/Crack; and Multiple-Substance Use. Variability in the number of missed HIV medication days and perceptions of substance use associated problems were observed across classes, with poorest adherence reported in the Alcohol and Marijuana class, the Alcohol and Cocaine/Crack class, and the Multiple-Substance Use class. The latter two classes also reported the greatest perceived impairment from substance use.

CONCLUSIONS

Patterns of recent substance use were associated with varying levels of HIV medication adherence and perceived substance use impairment, indicating that substance type matters when considering the health of older adults living with HIV, and that multiple-substance use needs to be addressed by interventions aimed at improving medication adherence.

The role of neuroplasticity and cognitive reserve in aging with HIV: recommendations for cognitive protection and rehabilitation

By and large, the immune systems of people infected with HIV are being protected and maintained by advances in highly active antiretroviral therapy; as such, this is extending the lives of people into old age. Unfortunately, for many living with this disease, HIV is associated with neuroinflammation, co-morbidities, and accelerated aging which can compromise brain function, resulting in cognitive deficits. The purpose of this article is to highlight how to interpret these deficits within the framework of neuroplasticity and cognitive reserve for this clinical population. We suggest several recommendations for cognitive rehabilitation and mitigation such as addressing lifestyle factors, psychostimulants, cognitive remediation therapy, and treatment of depression and anxiety. Implications for nursing research and practice are posited.

HIV and aging: effects on the central nervous system

With the introduction of combination antiretroviral therapy, many human immunodeficiency virus-positive (HIV+) individuals are reaching advanced age. The proportion of people living with HIV older than 50 years already exceeds 50% in many communities, and is expected to reach this level nationally by 2015. HIV and aging are independently associated with neuropathological changes, but their concurrence may have a more deleterious effect on the central nervous system (CNS). Published data about neurocognitive and neuroimaging markers of HIV and aging are reviewed. Putative factors contributing to neurocognitive impairment and neuroimaging changes in the aging HIV+ brain, such as metabolic disturbances, cardiovascular risk factors, immune senescence, and neuroinflammation, are described. The possible relationship between HIV and some markers of Alzheimer's disease is presented. Current research findings emphasize multiple mechanisms related to HIV and combination antiretroviral therapy that compromise CNS structure and function with advancing age.

Shallow encoding and forgetting are associated with dependence in instrumental activities of daily living among older adults living with HIV infection

Aging and HIV are both risk factors for memory deficits and declines in real-world functioning. However, we know little about the profile of memory deficits driving instrumental activities of daily living (IADL) declines across the lifespan in HIV. This study examined 145 younger (<50 years) and 119 older (≥50 years) adults with HIV who completed the California Verbal Learning Test-Second Edition (CVLT-II), the Wechsler Memory Scale-Third Edition Logical Memory subtest (WMS-III LM), and a modified Lawton and Brody ADL questionnaire. No memory predictors of IADL dependence emerged in the younger cohort. In the older group, IADL dependence was uniquely associated with worse performance on all primary CVLT-II variables, as well as elevated recency effects. Poorer immediate and delayed recall of the WMS-III LM was also associated with IADL dependence, although recognition was intact. Findings suggest older HIV-infected adults with shallow encoding and forgetting are at risk for IADL dependence.

Predictors of improvement following speed of processing training in middle-aged and older adults with HIV: a pilot study

Speed of processing training has been shown to improve cognitive functioning in normal older adults. A recent study demonstrated that middle-aged and older adults with HIV also improved on a measure of speed of processing and a measure of everyday functioning after such training. The primary objective was to examine what predicts the speed of processing training gains observed in the previous study. Participants were administered an extensive battery of demographic, psychosocial, and neuropsychological measures at baseline. They were randomized either to the speed of processing training group (n = 22) or to a no-contact control group (n = 24). Participants received approximately 10 hours of computerized speed of processing training. Predictors of training gains on the Useful Field of View (UFOV) Test and the Timed Instrumental Activities of Daily Living (TIADL) Test were examined through correlational analyses. In general, those who performed worse on the UFOV and TIADL at baseline demonstrated significantly more training gains. Also, higher HIV viral load, poorer medication adherence, a higher number of years diagnosed with HIV, and lower baseline scores on the Wisconsin Card Sorting Test (an executive functioning measure) were correlated with better TIADL training gains. TIADL performance improved in those with higher HIV viral load, poorer medication adherence, and poor executive functioning. Speed of processing training may be a way to improve everyday functioning and therefore quality of life in more medically and cognitively vulnerable adults with HIV.

HIV/AIDS in older women: unique challenges, unmet needs

As persons living with HIV/AIDS live longer, both the prevalence and incidence of HIV infection in older women is expected to increase, and this review presents a model and review of the extant literature on older women with HIV/AIDS in the United States. Older women are rarely addressed in the discourse about HIV risk and prevention, and their concerns are often missed by risk-reduction programs that typically target men and younger adults. Societal biases around aging can compound factors such as stigma and disclosure for older women. Primary care providers are often not recommending routine HIV testing to older women, or addressing the impact of age-related physiological changes on risk and sexual health. Many older women may be starting new relationships, so it is important that providers understand the relational variables specific to this group of women. Empirical research focused on the needs of older women, and recognition of the diverse composition and needs of this group, are needed to inform prevention, intervention, and best practices with this population of women.

Cognitive Consequences of Aging with HIV: Implications for Neuroplasticity and Rehabilitation

Combination active antiretroviral therapy prevents HIV from replicating and ravaging the immune system, thus allowing people to age with this disease. Unfortunately, the synergistic effects of HIV and aging can predispose many to become more at-risk of developing cognitive deficits which can interfere with medical management, everyday functioning, and quality of life. The purpose of this article is to describe the role of cognitive reserve and neuroplasticity on cognitive functioning in those aging with this disease. Specifically, the role of environment and the health of these individuals can compromise cognitive functioning. Fortunately, some cognitive interventions such as prevention and management of co-morbidities, cognitive remediation therapy, and neurotropic medications may be of value in preventing and rehabilitating the cognitive consequences of aging with HIV. Novel approaches such as cognitive prescriptions, transcranial direct stimulation, and binaural beat therapy may also be considered as possible techniques for cognitive rehabilitation.

Aging and HIV/AIDS: neurocognitive implications for older HIV-positive Latina/o adults

In recent years, HIV/AIDS populations have become older and increasingly more ethnically diverse. Concurrently, the prevalence of HIV-related neurocognitive (NC) impairment remains high. This study examined the effects of age and ethnicity on NC function in HIV-positive adults. The sample (N = 126; 84 Latina/o and 42 Non-Hispanic White) completed a comprehensive NC battery. Global NC and domain average demographically-corrected t-scores were generated. There were no significant differences between Younger (<50 years) Latina/os and non-Hispanic Whites on Global NC function or NC domains (all p's >.10), with generally small effect sizes. Older Latina/os (≥50 years) were significantly more impaired than Older Non-Hispanic Whites on processing speed and learning, with trends in Global NC function and memory. Further, effect sizes fell within the medium to large range (Cohen's d's = .49-1.15). This study suggests that older Latina/os are at potentially greater risk for NC impairment, particularly in processing speed and learning, when compared to similarly-aged non-Hispanic whites.