Neurocognitive SuperAging in Older Adults Living With HIV: Demographic, Neuromedical and Everyday Functioning Correlates

Correlates of SuperAging in Two Population-Based Samples of Hispanic Older Adults

OBJECTIVES

"SuperAgers" are generally defined as people 80+ years old with episodic memory performance comparable to those 20 years younger. Limited knowledge exists to describe characteristics of SuperAgers, with even less known about Hispanic SuperAgers.

METHODS

We examined indicators of cognitive, physical, and psychological resilience in relation to the likelihood of being a SuperAger using data from 2 population-based studies of Hispanic older adults (Puerto Rican Elderly: Health Conditions [PREHCO] Study; Health and Retirement Study [HRS]). SuperAgers were defined as (1) ≥80 years old, (2) recall scores ≥ the median for Hispanic respondents aged 55-64, and (3) no cognitive impairment during the observation period. Overall, 640 PREHCO participants and 180 HRS participants were eligible, of whom 45 (7%) and 31 (17%) met SuperAging criteria.

RESULTS

Logistic regressions controlling for age and sex demonstrated that higher education (PREHCO: odds ratio [OR] = 1.20, p < .001; HRS: OR = 1.14, p = .044) and fewer instrumental activities of daily living limitations (PREHCO: OR = 0.79, p = .019; HRS: OR = 0.58, p = .077; cognitive resilience), fewer activities of daily living limitations (PREHCO: OR = 0.72, p = .031; HRS: OR = 0.67, p = .068; physical resilience), and fewer depressive symptoms (PREHCO: OR = 0.84, p = .015; HRS: OR = 0.69, p = .007; psychological resilience) were associated with SuperAging, although not all results reached threshold for statistical significance, presumably due to low statistical power. Additionally, known indicators of physical health (e.g., chronic conditions and self-rated health) did not relate to SuperAging.

DISCUSSION

Increasing access to education and recognizing/treating depressive symptoms represent potential pathways to preserve episodic memory among older Hispanic adults.

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

PURPOSE OF REVIEW

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

RECENT FINDINGS

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

Cognitive impairment and neurocognitive profiles among people living with HIV and HIV-negative individuals older over 50 years: a comparison of IHDS, MMSE and MoCA

We aimed to examine the l differences in the assessment of neurocognitive impairment (NCI) using cognitive screening tools between PLWH and HIV-negative individuals and further compare the neurocognitive profiles between the two groups. This was baseline evaluation of Pudong HIV Aging Cohort, including 465 people living with HIV (PLWH) and 465 HIV-negative individuals aged over 50 years matched by age (± 3 years), sex and education. NCI was assessed using the Chinese version of Mini-mental State Examination (MMSE), the International HIV Dementia Scale (IHDS) and Beijing version of Montreal Cognitive Assessment (MoCA). In total, 258 (55.5%), 91 (19.6%), 273 (58.7%) of PLWH were classified as having NCI by the IHDS, MMSE and MoCA, compared to 90 (19.4%), 25 (5.4%), 135 (29.0%) of HIV-negative individuals, respectively (p < 0.05); such associations remained significant in multivariable analysis. PLWH showed a larger overlap of NCI detected by IHDS, MMSE, and MoCA. IHDS and MoCA detected almost all of the NCI detected by MMSE. IHDS-motor and psychomotor speeds and MoCA-executive function showed the greatest disparities between two groups. In multivariable analysis, older age and more depressive symptoms were positively associated with NCI regardless of the screening tools or HIV serostatus. PLWH over 50 years old display a higher prevalence of NCI and distinct neurocognitive profiles compared to HIV-negative individuals, despite viral suppression. Given the more considerable overlap in NCI classification in PLWH, it is advisable to choose one screening tool such as IHDS or MoCA to identify those potentially having NCI and then refer to more comprehensive neuropsychological assessment.

Implications of vascular depression for successful cognitive aging in HIV Disease

Although older adults with HIV are at high risk for mild neurocognitive disorders, a subset experience successful cognitive aging (SCA). HIV is associated with an increased risk of vascular depression (VasDep), which can affect cognitive and daily functioning. The current study examined whether VasDep impedes SCA among older adults with HIV. 136 persons with HIV aged 50 years and older were classified as either SCA+ (n = 37) or SCA- (n = 99) based on a battery of demographically adjusted neurocognitive tests and self-reported cognitive symptoms. Participants were also stratified on the presence of vascular disease (e.g., hypertension) and current depression as determined by the Composite International Diagnostic Interview and the Depression/Dejection scale of the Profile of Mood States. A Cochran-Armitage test revealed a significant additive effect of vascular disease and depression on SCA in this sample of older adults with HIV (z = 4.13, p <.0001). Individuals with VasDep had the lowest frequency of SCA+ (0%), which differed significantly from the group with only vascular disease (30%, OR = 0.04, CI = 0.002,0.68)) and the group with neither vascular disease nor depression (47% OR = 0.02, CI = 0.33,0.001). Findings were not confounded by demographics, HIV disease severity, or other psychiatric and medical factors (ps > 0.05). These data suggest that presence of VasDep may be a barrier to SCA in older adults with HIV disease. Prospective, longitudinal studies with neuroimaging-based operationalizations of VasDep are needed to further clarify this risk factor's role in the maintenance of cognitive and brain health in persons with HIV disease.

Implications of Vascular Depression for Successful Cognitive Aging in HIV disease

Introduction

Although older adults with HIV are at high risk for mild neurocognitive disorders, a subset experience successful cognitive aging (SCA). HIV is associated with an increased risk of vascular depression (VasDep), which can affect cognitive and daily functioning. The current study examined whether VasDep impedes SCA among older adults with HIV.

Methods

136 persons with HIV aged 50 years and older were classified as either SCA+ (n=37) or SCA- (n=99) based on a battery of demographically adjusted neurocognitive tests and self-reported cognitive symptoms. Participants were also stratified on the presence of vascular disease (e.g., hypertension) and current depression as determined by the Composite International Diagnostic Interview and the Depression/Dejection scale of the Profile of Mood States.

Results

A Cochran-Armitage test revealed a significant additive effect of vascular disease and depression on SCA in this sample of older adults with HIV (z=4.13, p<.0001). Individuals with VasDep had the lowest frequency of SCA+ (0%), which differed significantly from the group with only vascular disease (30%, OR=0.04, CI=0.002,0.68)) and the group with neither vascular disease nor depression (47% OR =0.02, CI=0.33,0.001). Findings were not confounded by demographics, HIV disease severity, or other psychiatric and medical factors (ps>.05).

Discussion

These data suggest that presence of VasDep may be a barrier to SCA in older adults with HIV disease. Prospective, longitudinal studies with neuroimaging-based operationalizations of VasDep are needed to further clarify this risk factor's role in the maintenance of cognitive and brain health in persons with HIV disease.

Cerebral abnormalities in HIV-infected individuals with neurocognitive impairment revealed by fMRI

Although the combination antiretroviral treatment (cART) has considerably lowered the risk of HIV associated dementia (HAD), the incidence of neurocognitive impairments (NCI) has not decreased likely due to the insidious and slow progressive nature of HIV infection. Recent studies showed that the resting-state functional magnetic resonance imaging (rs-fMRI) is a prominent technique in helping the non-invasive analysis of neucognitive impairment. Our study is to explore the neuroimaging characteristics among people living with HIV (PLWH) with or without NCI in terms of cerebral regional and neural network by rs-fMRI, based on the hypothesis that HIV patients with and without NCI have independent brain imaging characteristics. 33 PLWH with NCI and 33 PLWH without NCI, recruited from the Cohort of HIV-infected associated Chronic Diseases and Health Outcomes, Shanghai, China (CHCDO) which was established in 2018, were categorized into the HIV-NCI and HIV-control groups, respectively, based on Mini-Mental State Examination (MMSE) results. The two groups were matched in terms of sex, education and age. Resting-state fMRI data were collected from all participants to analyze the fraction amplitude of low-frequency fluctuation (fALFF) and functional connectivity (FC) to assess regional and neural network alterations in the brain. Correlations between fALFF/FC values in specific brain regions and clinical characteristics were also examined. The results showed increased fALFF values in the bilateral calcarine gyrus, bilateral superior occipital gyrus, left middle occipital gyrus, and left cuneus in the HIV-NCI group compared to the HIV-control group. Additionally, increased FC values were observed between the right superior occipital gyrus and right olfactory cortex, bilateral gyrus rectus, and right orbital part of the middle frontal gyrus in the HIV-NCI group. Conversely, decreased FC values were found between the left hippocampus and bilateral medial prefrontal gyrus, as well as bilateral superior frontal gyrus. The study concluded that abnormal spontaneous activity in PLWH with NCI primarily occurred in the occipital cortex, while defects in brain networks were mostly associated with the prefrontal cortex. The observed changes in fALFF and FC in specific brain regions provide visual evidence to enhance our understanding of the central mechanisms underlying the development of cognitive impairment in HIV patients.

Healthcare Provider Perspectives on HIV Cure Research in Ghana

Introduction

Antiretroviral therapy (ART) has reduced mortality and improved life expectancy among HIV patients but does not provide a cure. Patients must remain on lifelong medications and deal with drug resistance and side effects. This underscores the need for HIV cure research. However, participation in HIV cure research has risks without guaranteed benefits. We determined what HIV healthcare providers know about HIV cure research trials, the risks involved, and what kind of cure interventions they are likely to recommend for their patients.

Methods

We conducted in-depth qualitative interviews with 39 HIV care providers consisting of 12 physicians, 8 counsellors, 14 nurses, 2 pharmacists, 2 laboratory scientists, and 1 community advocate from three hospitals. Interviews were transcribed verbatim and coded, and thematic analysis was performed independently by two investigators.

Results

Participants were happy about the success of current treatments and hopeful that an HIV cure will be found in the near future, just as ART was discovered through research. They described cure as total eradication of the virus from the body and inability to test positive for HIV or transmit the virus. In terms of risk tolerance, respondents would recommend to their patients' studies with mild to moderate risks like what patients on antiretroviral therapy experience. Participants were reluctant to recommend treatment interruption to patients as part of a cure study and wished trials could be performed without stopping treatment. Healthcare providers categorically rejected death or permanent disability as an acceptable risk. The possibility of finding a cure that will benefit the individual or future generations was strong motivations for providers to recommend cure trials to their patients, as was transparency and adequate information on proposed trials. Overall, the participants were not actively seeking knowledge on cure research and lacked information on the various cure modalities under investigation.

Conclusion

While hopeful for an HIV cure, healthcare providers in Ghana expect a cure to be definitive and pose minimal risk to their patients.

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

BACKGROUND

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

METHODS

Participants included 396 older PWH (age range: 50-69 years) who completed cross-sectional neuropsychological and neuromedical evaluations. Using published criteria, participants exhibiting global neurocognition within normative expectations of healthy 25-year-olds were classified as SuperAgers (SA; n = 57). Cognitively normal (CN; n = 172) and impaired (n = 167) participants were classified with chronological age-based norms. Cognitive reserve was operationalized with an estimate of premorbid verbal intelligence, and physiologic reserve was operationalized with a cumulative index of 39 general and HIV-specific health variables. Analysis of variance with confirmatory multinomial logistic regression examined linear and quadratic effects of cognitive and physiologic reserve on SA status, adjusting for chronological age, depression, and race/ethnicity.

RESULTS

Univariably, SA exhibited significantly higher cognitive and physiologic reserve compared with CN and cognitively impaired ( d s ≥ 0.38, p s < 0.05). Both reserve factors independently predicted SA status in multinomial logistic regression; higher physiologic reserve predicted linear increases in odds of SA, and higher cognitive reserve predicted a quadratic "J-shaped" change in odds of SA compared with CN (ie, odds of SA > CN only above 35th percentile of cognitive reserve).

CONCLUSIONS

Each reserve factor uniquely related to SA status, which supports the construct validity of our SA criteria and suggests cognitive and physiologic reserve reflect nonoverlapping pathways of neuroprotection in HIV. Incorporation of proxy markers of reserve in clinical practice may improve characterization of age-related cognitive risk and resilience among older PWH, even among PWH without overt neurocognitive impairment.

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

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

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

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

Neopterin Relates to Lifetime Depression in Older Adults With HIV on Suppressive Antiretroviral Therapy

BACKGROUND

Chronic inflammation contributes to the pathogenesis of depression in persons with HIV (PWH). Neopterin, a biomarker of HIV-related immune activation that partially normalizes with antiretroviral therapy (ART), correlates with major depressive disorder (MDD) and subclinical depressive symptoms in persons without HIV and acutely infected, young PWH. The sensitivity of neopterin, however, to both lifetime and current depression is poorly understood in older PWH on suppressive ART.

METHODS

Participants were 70 PWH and 35 persons without HIV (HIV-) who were at least 50 years old and completed standardized neurobehavioral and neuromedical assessments. Depressive symptoms in the past 2 weeks, measured with the Beck Depression Inventory-II (BDI-II), and lifetime MDD diagnoses, defined as meeting Diagnostic and Statistical Manual of Mental Disorders-IV criteria for a depressive episode at any point in one's lifetime, were separately modeled as a function of plasma neopterin levels in the full sample and by HIV serostatus.

RESULTS

Compared with HIV- adults, PWH had higher neopterin levels (P < 0.001) and BDI-II scores (P < 0.01) and were more likely to have lifetime MDD (P < 0.01). Higher neopterin related to lifetime MDD, but only in PWH, even after controlling for clinically relevant comorbidities and treatment factors in logistic regression (odds ratio = 3.11, P = 0.002). Higher neopterin correlated with higher BDI-II scores in the full sample (rs = 0.25; P = 0.010), but not within either group (PWH: rs = 0.03, P = 0.819; HIV-: rs = 0.09, P = 0.588).

CONCLUSION

Neopterin was associated with lifetime MDD, but not current depressive symptoms in older PWH on suppressive ART. This may reflect a legacy of inflammation-related disruptions to amino acid metabolism and neurotransmitter synthesis, similar to prior observations. Identification of biopsychosocial and resilience factors underlying the null association between neopterin and current depression in older PWH is warranted.

Factors partitioning physical frailty in people aging with HIV: A classification and regression tree approach

OBJECTIVE

To estimate the extent to which comorbidity and lifestyle factors were associated with physical frailty in middle-aged and older Canadians living with HIV.

DESIGN

Cross-sectional analysis of 856 participants from the Canadian Positive Brain Health Now cohort.

METHODS

The frailty indicator phenotype was adapted from Fried's criteria using self-report items. Univariate logistic regression and classification and regression tree (CaRT) models were used to identify the most relevant independent contributors to frailty.

RESULTS

In all, 100 men (14.0%) and 26 women (19.7%) were identified as frail (≥ 3/5 criteria) for an overall prevalence of 15.2%. Nine comorbidities showed an influential association with frailty. The most influential comorbidities were hypothyroidism [odds ratio (OR) = 2.55, 95% confidence interval (CI): 1.29-50.3] and arthritis (OR = 2.54, 95% CI: 1.58-4.09). Additionally, tobacco (OR = 1.79, 95% CI: 1.05-3.04) showed an association. Any level of alcohol consumption showed a protective effect for frailty. The CaRT model showed nine pathways that led to frailty. Arthritis was the most discriminatory variable followed by alcohol, hypothyroidism, tobacco, cancer, cannabis, liver disease, kidney disease, osteoporosis, lung disease and peripheral vascular disease. The prevalence of physical frailty for people with arthritis was 27.4%; with additional cancer or tobacco and alcohol the prevalence rates were 47.1% and 46.1%, respectively. The protective effect of alcohol consumption evident in the univariate model appeared again in the CaRT model, but this effect varied. Cognitive frailty (19.5% overall) and emotional frailty (37.9% overall) were higher than the prevalence of physical frailty.

CONCLUSIONS

Specific comorbidities and tobacco use were implicated in frailty, suggesting that it is comorbidities causing frailty. However, some frailty still appears to be HIV-related. The higher prevalence of cognitive and emotional frailty highlights the fact that physical frailty should not be the only focus in HIV.

Pathophysiological Consequences of At-Risk Alcohol Use; Implications for Comorbidity Risk in Persons Living With Human Immunodeficiency Virus

At-risk alcohol use is a significant risk factor associated with multisystemic pathophysiological effects leading to multiorgan injury and contributing to 5.3% of all deaths worldwide. The alcohol-mediated cellular and molecular alterations are particularly salient in vulnerable populations, such as people living with HIV (PLWH), diminishing their physiological reserve, and accelerating the aging process. This review presents salient alcohol-associated mechanisms involved in exacerbation of cardiometabolic and neuropathological comorbidities and their implications in the context of HIV disease. The review integrates consideration of environmental factors, such as consumption of a Western diet and its interactions with alcohol-induced metabolic and neurocognitive dyshomeostasis. Major alcohol-mediated mechanisms that contribute to cardiometabolic comorbidity include impaired substrate utilization and storage, endothelial dysfunction, dysregulation of the renin-angiotensin-aldosterone system, and hypertension. Neuroinflammation and loss of neurotrophic support in vulnerable brain regions significantly contribute to alcohol-associated development of neurological deficits and alcohol use disorder risk. Collectively, evidence suggests that at-risk alcohol use exacerbates cardiometabolic and neurocognitive pathologies and accelerates biological aging leading to the development of geriatric comorbidities manifested as frailty in PLWH.

A pilot study of cognition and creativity among persons with HIV disease referred for neuropsychological evaluation

Creativity can help people to innovate, overcome obstacles, and successfully navigate challenges in daily life. Some aspects of creativity rely on the prefrontostriatal loops and executive functions, which can be compromised in persons with HIV (PWH). This pilot study examined whether neuropsychological functioning plays a role in creativity in PWH. A consecutive series of 41 PWH who were referred to an urban neuropsychology clinic in southeastern Texas were enrolled. Participants completed the Abbreviated Torrance Test for Adults (ATTA) to measure creativity, from which standardized creativity scores of fluency, originality, elaboration, and flexibility were derived. Participants also completed several measures of everyday functioning and a brief clinical neuropsychological battery measuring executive functions, motor skills, memory, and visuoconstruction. Global neuropsychological functioning showed a large, positive association with ATTA creativity performance that did not vary meaningfully by creativity domain and was independent of premorbid IQ. ATTA creativity scores were not associated with any measure of everyday functioning. Findings from this pilot study suggest that higher levels of neuropsychological functioning may support multiple dimensions of creativity in adults with HIV disease. Future studies might examine whether creativity moderates the association between HIV-associated neurocognitive impairment and various health behaviors (e.g., adherence, appointment attendance).

Predicting occupational outcomes from neuropsychological test performance in older people with HIV

OBJECTIVE

The ability to work is amongst the top concerns of people living with well treated HIV. Cognitive impairment has been reported in many otherwise asymptomatic persons living with HIV and even mild impairment is associated with higher rates of occupational difficulties. There are several classification algorithms for HIV-associated neurocognitive disorder (HAND) as well as overall scoring methods available to summarize neuropsychological performance. We asked which method best explained work status and productivity.

DESIGN

Participants (N = 263) drawn from a longitudinal Canadian cohort underwent neuropsychological testing.

METHODS

: Several classification algorithms were applied to establish a HAND diagnosis and two summary measures (NPZ and Global Deficit Score) were computed. Self-reported work status and productivity was assessed at each study visit (four visits, 9 months apart). The association of work status with each diagnostic classification and summary measure was estimated using logistic regression. For those working, the value on the productivity scale was regressed within individuals over time, and the slopes were regressed on each neuropsychological outcome.

RESULTS

The application of different classification algorithms to the neuropsychological data resulted in rates of impairment that ranged from 28.5 to 78.7%. Being classified as impaired by any method was associated with a higher rate of unemployment. None of the diagnostic classifications or summary methods predicted productivity, at time of testing or over the following 36 months.

CONCLUSION

Neuropsychological diagnostic classifications and summary scores identified participants who were more likely to be unemployed, but none explained productivity. New methods of assessing cognition are required to inform optimal workforce engagement.

Subgroup Analysis of Individuals with Multiple Sclerosis Showing Cognitive Resilience

OBJECTIVE

Cognitive dysfunction is known to occur in many individuals with multiple sclerosis (MS). However, little is currently known about MS patients without cognitive impairment, including protective factors associated with intact cognition. The present study considered these issues in a sample of MS patients screened for intact subjective and objective cognitive functioning.

METHODS

Two MS participant groups from a larger sample were derived: i) participants within 1 standard deviation of controls on measures of objective cognition, subjective cognition, and informant-observed subjective cognition [cognitively resilient MS group (MScr)], and ii) those classified as not cognitively resilient (MSncr). Both groups were compared with age- and gender-matched controls.

RESULTS

Findings indicated that the MScr group was similar to the MSncr group on most disease and demographic variables, and level of fatigue. The MScr group showed higher estimated baseline intellectual ability and reported less anxiety, subclinical depressive symptoms, and pain interference. MScr participants also showed a trend toward more reported compensatory cognitive strategy use than MSncr participants. The MScr group showed comparable reading recognition and pain symptoms to controls.

CONCLUSIONS

Our findings provide preliminary information on factors associated with cognitive resilience in MS. Future research should examine resilient individuals with MS to further clarify positive outcomes in this condition.

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.

Redistribution of brain glucose metabolism in people with HIV after antiretroviral therapy initiation

OBJECTIVE

We evaluated brain glucose metabolism in people living with HIV (PWH) with [18F]-Fluoro-Deoxyglucose (FDG) PET/computed tomography (CT) before and after antiretroviral therapy (ART) initiation.

DESIGN

We conducted a longitudinal study wherein ART-naive late-presenting untreated PWH with CD4+ cell counts less than 100 cells/μl were prospectively assessed for FDG uptake at baseline and at 4-8 weeks (n = 22) and 19-26 months (n = 11) following ART initiation.

METHODS

Relative uptake in the subcortical regions (caudate, putamen and thalamus) and cortical regions (frontal, parietal, temporal and occipital cortices) were compared across time and correlated with biomarkers of disease activity and inflammation, in addition to being compared with a group of uninfected individuals (n = 10).

RESULTS

Before treatment initiation, putaminal and caudate relative FDG uptake values in PWH were significantly higher than in uninfected controls. Relative putaminal and thalamic uptake significantly decreased shortly following ART initiation, while frontal cortex values significantly increased. FDG uptake changes correlated with changes in CD4+ cell counts and viral load, and, in the thalamus, with IL-6R and sCD14. Approximately 2 years following ART initiation, there was further decrease in subcortical relative uptake values, reaching levels below those of uninfected controls.

CONCLUSION

Our findings support pretreatment basal ganglia and thalamic neuroinflammatory changes in PWH, which decrease after treatment with eventual unmasking of long-term irreversible neuronal damage. Meanwhile, increased frontal cortex metabolism following ART initiation suggests reversible cortical dysfunction which improves with virologic control and increased CD4+ cell counts. Early initiation of treatment after HIV diagnosis and secondary control of inflammation are thus necessary to halt neurological damage in PWH.

Confound, Cause, or Cure: The Effect of Cannabinoids on HIV-Associated Neurological Sequelae

The persistence of human immunodeficiency virus-1 (HIV)-associated neurocognitive disorders (HAND) in the era of effective antiretroviral therapy suggests that modern HIV neuropathogenesis is driven, at least in part, by mechanisms distinct from the viral life cycle. Identifying more subtle mechanisms is complicated by frequent comorbidities in HIV⁺ populations. One of the common confounds is substance abuse, with cannabis being the most frequently used psychoactive substance among people living with HIV. The psychoactive effects of cannabis use can themselves mimic, and perhaps magnify, the cognitive deficits observed in HAND; however, the neuromodulatory and anti-inflammatory properties of cannabinoids may counter HIV-induced excitotoxicity and neuroinflammation. Here, we review our understanding of the cross talk between HIV and cannabinoids in the central nervous system by exploring both clinical observations and evidence from preclinical in vivo and in vitro models. Additionally, we comment on recent advances in human, multi-cell in vitro systems that allow for more translatable, mechanistic studies of the relationship between cannabinoid pharmacology and this uniquely human virus.

The Intersection of Cognitive Ability and HIV: A Review of the State of the Nursing Science

ABSTRACT

Neurocognitive problems have been endemic to the HIV epidemic since its beginning. Four decades later, these problems persist, but currently, they are attributed to HIV-induced inflammation, the long-term effects of combination antiretroviral therapy, lifestyle (i.e., physical activity, drug use), psychiatric, and age-associated comorbidities (i.e., heart disease, hypertension). In many cases, persons living with HIV (PLWH) may develop cognitive problems as a function of accelerated or accentuated normal aging and lifestyle rather than HIV itself. Nonetheless, such cognitive impairments can interfere with HIV care, including medication adherence and attending clinic appointments. With more than half of PLWH 50 years and older, and 30%-50% of all PLWH meeting the criteria for HIV-associated neurocognitive disorder, those aging with HIV may be more vulnerable to developing cognitive problems. This state of the science article provides an overview of current issues and provides implications for practice, policy, and research to promote successful cognitive functioning in PLWH.

HIV, Vascular Risk Factors, and Cognition in the Combination Antiretroviral Therapy Era: A Systematic Review and Meta-Analysis

OBJECTIVES

Mounting evidence indicates that vascular risk factors (VRFs) are elevated in HIV and play a significant role in the development and persistence of HIV-associated neurocognitive disorder. Given the increased longevity of people living with HIV (PLWH), there is a great need to better elucidate vascular contributions to neurocognitive impairment in HIV. This systematic review and meta-analysis examine relationships between traditional VRFs, cardiovascular disease (CVD), and cognition in PLWH in the combination antiretroviral therapy era.

METHODS

For the systematic review, 44 studies met inclusion criteria and included data from 14,376 PLWH and 6,043 HIV-seronegative controls. To better quantify the contribution of VRFs to cognitive impairment in HIV, a robust variance estimation meta-analysis (N = 11 studies) was performed and included data from 2139 PLWH.

RESULTS

In the systematic review, cross-sectional and longitudinal studies supported relationships between VRFs, cognitive dysfunction, and decline, particularly in the domains of attention/processing speed, executive functioning, and fine motor skills. The meta-analysis demonstrated VRFs were associated with increased odds of global neurocognitive impairment (odds ratio [OR ]= 2.059, p = .010), which remained significant after adjustment for clinical HIV variables (p = .017). Analyses of individual VRFs demonstrated type 2 diabetes (p = .004), hyperlipidemia (p = .043), current smoking (p = .037), and previous CVD (p = .0005) were significantly associated with global neurocognitive impairment.

CONCLUSIONS

VRFs and CVD are associated with worse cognitive performance and decline, and neurocognitive impairment in PLWH. Future studies are needed to examine these relationships in older adults with HIV, and investigate how race/ethnicity, gender, medical comorbidities, and psychosocial factors contribute to VRF-associated cognitive dysfunction in HIV.

Patterns and Predictors of Cognitive Function Among Virally Suppressed Women With HIV

Cognitive impairment remains frequent and heterogeneous in presentation and severity among virally suppressed (VS) women with HIV (WWH). We identified cognitive profiles among 929 VS-WWH and 717 HIV-uninfected women from 11 Women's Interagency HIV Study sites at their first neuropsychological (NP) test battery completion comprised of: Hopkins Verbal Learning Test-Revised, Trail Making, Symbol Digit Modalities, Grooved Pegboard, Stroop, Letter/Animal Fluency, and Letter-Number Sequencing. Using 17 NP performance metrics (T-scores), we used Kohonen self-organizing maps to identify patterns of high-dimensional data by mapping participants to similar nodes based on T-scores and clustering those nodes. Among VS-WWH, nine clusters were identified (entropy = 0.990) with four having average T-scores ≥45 for all metrics and thus combined into an "unimpaired" profile (n = 311). Impaired profiles consisted of weaknesses in: (1) sequencing (Profile-1; n = 129), (2) speed (Profile-2; n = 144), (3) learning + recognition (Profile-3; n = 137), (4) learning + memory (Profile-4; n = 86), and (5) learning + processing speed + attention + executive function (Profile-5; n = 122). Sociodemographic, behavioral, and clinical variables differentiated profile membership using Random Forest models. The top 10 variables distinguishing the combined impaired vs. unimpaired profiles were: clinic site, age, education, race, illicit substance use, current and nadir CD4 count, duration of effective antiretrovirals, and protease inhibitor use. Additional variables differentiating each impaired from unimpaired profile included: depression, stress-symptoms, income (Profile-1); depression, employment (Profile 2); depression, integrase inhibitor (INSTI) use (Profile-3); employment, INSTI use, income, atazanavir use, non-ART medications with anticholinergic properties (Profile-4); and marijuana use (Profile-5). Findings highlight consideration of NP profile heterogeneity and potential modifiable factors contributing to impaired profiles.

The Current State of HIV and Aging: Findings Presented at the 10th International Workshop on HIV and Aging

With increasing effectiveness of antiretroviral therapy, people with HIV (PWH) are living longer and the prevalence of older PWH continues to increase. Accordingly, PWH are experiencing an increased burden of age-related comorbidities. With this shifting demographics, clinicians and researchers face additional challenges in how to identify, address, and manage the complex intersections of HIV- and aging-related conditions. Established in 2009, the International Workshop on HIV and Aging brings together clinicians and researchers in cross-disciplinary fields along with community advocates and PWH to address the multidisciplinary nature of HIV and aging. This article summarizes plenary talks from the 10th Annual International Workshop on HIV and Aging, which took place in New York City on October 10 and 11, 2019. Presentation topics included the following: the burdens of HIV-associated comorbidities, aging phenotypes, community engagement, and loneliness; these issues are especially important for older PWH, considering the current COVID-19 pandemic. We also discuss broad questions and potential directions for future research necessary to better understand the interaction between HIV and aging.

Astrocytes, HIV and the Glymphatic System: A Disease of Disrupted Waste Management?

The discovery of the glial-lymphatic or glymphatic fluid clearance pathway in the rodent brain led researchers to search for a parallel system in humans and to question the implications of this pathway in neurodegenerative diseases. Magnetic resonance imaging studies revealed that several features of the glymphatic system may be present in humans. In both rodents and humans, this pathway promotes the exchange of interstitial fluid (ISF) and cerebrospinal fluid (CSF) through the arterial perivascular spaces into the brain parenchyma. This process is facilitated in part by aquaporin-4 (AQP4) water channels located primarily on astrocytic end feet that abut cerebral endothelial cells of the blood brain barrier. Decreased expression or mislocalization of AQP4 from astrocytic end feet results in decreased interstitial flow, thereby, promoting accumulation of extracellular waste products like hyperphosphorylated Tau (pTau). Accumulation of pTau is a neuropathological hallmark in Alzheimer's disease (AD) and is accompanied by mislocalization of APQ4 from astrocyte end feet to the cell body. HIV infection shares many neuropathological characteristics with AD. Similar to AD, HIV infection of the CNS contributes to abnormal aging with altered AQP4 localization, accumulation of pTau and chronic neuroinflammation. Up to 30% of people with HIV (PWH) suffer from HIV-associated neurocognitive disorders (HAND), and changes in AQP4 may be clinically important as a contributor to cognitive disturbances. In this review, we provide an overview and discussion of the potential contributions of NeuroHIV to glymphatic system functions by focusing on astrocytes and AQP4. Although HAND encompasses a wide range of neurocognitive impairments and levels of neuroinflammation vary among and within PWH, the potential contribution of disruption in AQP4 may be clinically important in some cases. In this review we discuss implications for possible AQP4 disruption on NeuroHIV disease trajectory and how HIV may influence AQP4 function.

Methamphetamine and Cannabis: A Tale of Two Drugs and their Effects on HIV, Brain, and Behavior

HIV infection and drug use intersect epidemiologically, and their combination can result in complex effects on brain and behavior. The extent to which drugs affect the health of persons with HIV (PWH) depends on many factors including drug characteristics, use patterns, stage of HIV disease and its treatment, comorbid factors, and age. To consider the range of drug effects, we have selected two that are in common use by PWH: methamphetamine and cannabis. We compare the effects of methamphetamine with those of cannabis, to illustrate how substances may potentiate, worsen, or even buffer the effects of HIV on the CNS. Data from human, animal, and ex vivo studies provide insights into how these drugs have differing effects on the persistent inflammatory state that characterizes HIV infection, including effects on viral replication, immune activation, mitochondrial function, gut permeability, blood brain barrier integrity, glia and neuronal signaling. Moving forward, we consider how these mechanistic insights may inform interventions to improve brain outcomes in PWH. This review summarizes literature from clinical and preclinical studies demonstrating the adverse effects of METH, as well as the potentially beneficial effects of cannabis, on the interacting systemic (e.g., gut barrier leakage/microbial translocation, immune activation, inflammation) and CNS-specific (e.g., glial activation/neuroinflammation, neural injury, mitochondrial toxicity/oxidative stress) mechanisms underlying HIV-associated neurocognitive disorders.

A Systematic Review of the Neurocognitive Effects of Cannabis Use in Older Adults

Purpose of Review

Older adults currently represent the fastest growing demographic of cannabis users, yet few studies have investigated the effects of cannabis use on cognitive functioning in aging. We conducted a systematic review of the recent literature examining cognitive outcomes associated with cannabis use in older adults, with and without neurocognitive disorders, to clarify the potential neuroprotective benefits and risks of cognitive decline in this population.

Recent Findings

We identified 26 studies examining cognitive outcomes associated with medical and recreational use of cannabis in healthy aging, dementia, Parkinson's disease, multiple sclerosis, HIV, and pain populations. Although variability in the cannabis products used, outcomes assessed, and study quality limits the conclusions that can be made, modest reductions in cognitive performance were generally detected with higher doses and heavier lifetime use.

Summary

This review highlights the need for additional high-quality research using standardized, validated assessments of cannabis exposure and cognitive outcomes. Reliable measures and longitudinal data are necessary to better characterize the effects of cannabis use on cognitive aging, as well as differential effects of recreational and medical cannabis.