Motor function declines over time in human immunodeficiency virus and is associated with cerebrovascular disease, while HIV-associated neurocognitive disorder remains stable

Exercise to Prevent Accelerated Vascular Aging in People Living With HIV

Given advances in antiretroviral therapy, the mortality rate for HIV infection has dropped considerably over recent decades. However, people living with HIV (PLWH) experience longer life spans coupled with persistent immune activation despite viral suppression and potential toxicity from long-term antiretroviral therapy use. Consequently, PLWH face a cardiovascular disease (CVD) risk more than twice that of the general population, making it the leading cause of death among this group. Here, we briefly review the epidemiology of CVD in PLWH highlighting disparities at the intersections of sex and gender, age, race/ethnicity, and the contributions of social determinants of health and psychosocial stress to increased CVD risk among individuals with marginalized identities. We then overview the pathophysiology of HIV and discuss the primary factors implicated as contributors to CVD risk among PLWH on antiretroviral therapy. Subsequently, we highlight the functional evidence of premature vascular dysfunction as an early pathophysiological determinant of CVD risk among PLWH, discuss several mechanisms underlying premature vascular dysfunction in PLWH, and synthesize current research on the pathophysiological mechanisms underlying accelerated vascular aging in PLWH, focusing on immune activation, chronic inflammation, and oxidative stress. We consider understudied aspects such as HIV-related changes to the gut microbiome and psychosocial stress, which may serve as mechanisms through which exercise can abrogate accelerated vascular aging. Emphasizing the significance of exercise, we review various modalities and their impacts on vascular health, proposing a holistic approach to managing CVD risks in PLWH. The discussion extends to critical future study areas related to vascular aging, CVD, and the efficacy of exercise interventions, with a call for more inclusive research that considers the diversity of the PLWH population.

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.

Microglial- neuronal crosstalk in chronic viral infection through mTOR, SPP1/OPN and inflammasome pathway signaling

HIV-infection of microglia and macrophages (MMs) induces neuronal injury and chronic release of inflammatory stimuli through direct and indirect molecular pathways. A large percentage of people with HIV-associated neurologic and psychiatric co-morbidities have high levels of circulating inflammatory molecules. Microglia, given their susceptibility to HIV infection and long-lived nature, are reservoirs for persistent infection. MMs and neurons possess the molecular machinery to detect pathogen nucleic acids and proteins to activate innate immune signals. Full activation of inflammasome assembly and expression of IL-1β requires a priming event and a second signal. Many studies have demonstrated that HIV infection alone can activate inflammasome activity. Interestingly, secreted phosphoprotein-1 (SPP1/OPN) expression is highly upregulated in the CNS of people infected with HIV and neurologic dysfunction. Interestingly, all evidence thus far suggests a protective function of SPP1 signaling through mammalian target of rapamycin (mTORC1/2) pathway function to counter HIV-neuronal injury. Moreover, HIV-infected mice knocked down for SPP1 show by neuroimaging, increased neuroinflammation compared to controls. This suggests that SPP1 uses unique regulatory mechanisms to control the level of inflammatory signaling. In this mini review, we discuss the known and yet-to-be discovered biological links between SPP1-mediated stimulation of mTOR and inflammasome activity. Additional new mechanistic insights from studies in relevant experimental models will provide a greater understanding of crosstalk between microglia and neurons in the regulation of CNS homeostasis.

Alcohol Consumption and Illicit Drug Use: Associations With Fall, Fracture, and Acute Health Care Utilization Among People With HIV Infection

BACKGROUND

Given alcohol and/or other drug (AOD) use occurs among people with HIV (PWH), we examined its association with falls and fall-related outcomes and whether frailty moderates the association.

SETTING

Northeastern US city.

METHODS

We analyzed an observational cohort of PWH with current or past AOD use. Alcohol measures were any past 14-day heavy use, average alcohol/day, and days with heavy use. Drug use measures were past 30-day illicit use of cocaine, opioids, and sedatives. Repeated cross-sectional associations were estimated with separate multivariable generalized estimating equation regression models for each fall-related outcome.

RESULTS

Among PWH (n = 251; mean age 52 [SD = 10]), 35% reported heavy alcohol use, 24% cocaine, 16% illicit opioids, 13% illicit sedatives, and 35% any fall; 27% were frail. Heavy alcohol use was associated with a fall (AOR = 1.49, 95% CI: 1.08 to 2.07), multiple falls (AOR = 1.55 95% CI: 1.10 to 2.19), and fall/fracture-related emergency department visit or hospitalization (AOR = 1.81, 95% CI: 1.10 to 2.97). Higher average alcohol/day and more heavy drinking days were associated with multiple falls. Illicit sedative use was associated with a fall, multiple falls, and emergency department visit/hospitalization and opioid use with fracture. Frailty moderated the association of heavy alcohol use and a fall (AOR = 2.26, 95% CI: 1.28 to 4.01 in those frail) but not in those not frail.

CONCLUSION

The effect of AOD use on falls and fall-related outcomes was most pronounced with alcohol, particularly among frail PWH. Heavy alcohol, illicit sedative, and illicit opioid use are high-priority targets for preventing falls and fall-related consequences for PWH.

Clinical markers of HIV predict redox-regulated neural and behavioral function in the sensorimotor system

Even in the modern era of combination antiretroviral therapy, aberrations in motor control remain a predominant symptom contributing to age-related functional dependencies (e.g., neurocognitive impairment) in people with HIV (PWH). While recent evidence implicates aberrant mitochondrial redox environments in the modulation of neural oscillatory activity serving motor control in PWH, the contribution of important clinical and demographic factors on this bioenergetic-neural-behavioral pathway is unknown. Herein, we evaluate the predictive capacity of clinical metrics pertinent to HIV (e.g., CD4 nadir, time with viremia) and age on mitochondrial redox-regulated sensorimotor brain-behavior dynamics in 69 virally-suppressed PWH. We used state-of-the-art systems biology and neuroscience approaches, including Seahorse analyzer of mitochondrial energetics, EPR spectroscopy of intracellular oxidant levels, antioxidant activity assays pertinent to superoxide and hydrogen peroxide (H2O2) redox environments, and magnetoencephalographic (MEG) imaging to quantify sensorimotor oscillatory dynamics. Our results demonstrate differential effects of redox systems on the neural dynamics serving motor function in PWH. In addition, measures of immune stability and duration of compromise due to HIV had dissociable effects on this pathway, above and beyond the effects of age alone. Moreover, peripheral measures of antioxidant activity (i.e., superoxide dismutase) fully mediated the relationship between immune stability and current behavioral performance, indicative of persistent oxidative environments serving motor control in the presence of virologic suppression. Taken together, our data suggest that disease-related factors, in particular, are stronger predictors of current redox, neural and behavioral profiles serving motor function, which may serve as effective targets for alleviating HIV-specific alterations in cognitive-motor function in the future.

Physical functioning in adolescents with perinatal HIV

Perinatal HIV impacts on growth and development in childhood, with physical impairments such as growth limitations, decreased physical activity, reduced exercise tolerance and cardiopulmonary dysfunction continuing into adolescence. There is limited data on other physical functioning domains in perinatally HIV-infected adolescents (PHIVA) thus the aim of this study was to establish the physical sequelae of perinatal HIV in adolescents. This South African cross-sectional study compared PHIVA with HIV-negative adolescents, assessing anthropometry, muscle strength, endurance and motor performance. All ethical considerations were adhered to. The study included 147 PHIVA and 102 HIV-negative adolescents, aged 10-16 years. The majority (87.1%) of PHIVA were virally suppressed however, they still showed significant deficits in height (p < 0.001), weight (p < 0.001) and BMI (p = 0.004). Both groups performed poorly in muscle strength and endurance but did not differ significantly. In motor performance, the PHIVA scored significantly lower for manual dexterity and balance, with significantly more PHIVA with motor difficulty. A regression analysis showed that viral suppression predicted muscle strength (p = 0.032) and age positively predicted endurance (p = 0.044) and negatively predicated aiming and catching (p = 0.009). In conclusion, PHIVA face growth deficits and challenges with motor performance, especially with manual dexterity and balance.

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

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

Mitochondrial redox environments predict sensorimotor brain-behavior dynamics in adults with HIV

Despite virologic suppression, people living with HIV (PLWH) remain at risk for developing cognitive impairment, with aberrations in motor control being a predominant symptom leading to functional dependencies in later life. While the neuroanatomical bases of motor dysfunction have recently been illuminated, the underlying molecular processes remain poorly understood. Herein, we evaluate the predictive capacity of the mitochondrial redox environment on sensorimotor brain-behavior dynamics in 40 virally-suppressed PLWH and 40 demographically-matched controls using structural equation modeling. We used state-of-the-art approaches, including Seahorse Analyzer of mitochondrial function, electron paramagnetic resonance spectroscopy to measure superoxide levels, antioxidant activity assays and dynamic magnetoencephalographic imaging to quantify sensorimotor oscillatory dynamics. We observed differential modulation of sensorimotor brain-behavior relationships by superoxide and hydrogen peroxide-sensitive features of the redox environment in PLWH, while only superoxide-sensitive features were related to optimal oscillatory response profiles and better motor performance in controls. Moreover, these divergent pathways may be attributable to immediate, separable mechanisms of action within the redox environment seen in PLWH, as evidenced by mediation analyses. These findings suggest that mitochondrial redox parameters are important modulators of healthy and pathological oscillations in motor systems and behavior, serving as potential targets for remedying HIV-related cognitive-motor dysfunction in the future.

Osteopontin/secreted phosphoprotein-1 harnesses glial-, immune-, and neuronal cell ligand-receptor interactions to sense and regulate acute and chronic neuroinflammation

Osteopontin (OPN) also known by its official gene designation secreted phosphoprotein-1 (SPP1) is a fascinating, multifunctional protein expressed in a number of cell types that functions not only in intercellular communication, but also in the extracellular matrix (ECM). OPN/SPP1 possesses cytokine, chemokine, and signal transduction functions by virtue of modular structural motifs that provide interaction surfaces for integrins and CD44-variant receptors. In humans, there are three experimentally verified splice variants of OPN/SPP1 and CD44's ten exons are also alternatively spiced in a cell/tissue-specific manner, although very little is known about how this is regulated in the central nervous system (CNS). Post-translational modifications of phosphorylation, glycosylation, and localized cleavage by specific proteases in the cells and tissues where OPN/SPP1 functions, provides additional layers of specificity. However, the former make elucidating the exact molecular mechanisms of OPN/SPP1 function more complex. Flexibility in OPN/SPP1 structure and its engagement with integrins having the ability to transmit signals in inside-out and outside-in direction, is likely why OPN/SPP1 can serve as an early detector of inflammation and ongoing tissue damage in response to cancer, stroke, traumatic brain injury, pathogenic infection, and neurodegeneration, processes that impair tissue homeostasis. This review will focus on what is currently known about OPN/SPP1 function in the brain.

Alcohol and falls among people with HIV infection: A view from Russia and the United States

BACKGROUND

Both human immunodeficiency virus (HIV) infection and alcohol use predispose to autonomic/sensory neuropathy, imbalance symptoms, and cognitive impairment-conditions associated with a greater risk of falls-yet it is unclear how to identify people with HIV (PWH) whose drinking is associated with falls. Research on alcohol and falls using the same instruments in different countries could help to specify the level of alcohol use associated with fall risk. We examined whether a consumption-based measure (the Alcohol Use Disorders Identification Test-Consumption [AUDIT-C]) and/or a symptom-based measure (DSM-5 criteria for alcohol use disorder [AUD]) are associated with sustaining a fall among PWH in St Petersburg, Russia and Boston, Massachusetts in the United States.

METHODS

Separate multivariate logistic regressions were used for each cohort to examine cross-sectional associations for each alcohol measure predicting fall. Potential confounders included physical functioning, depressive symptoms, and other substance use (measured with the Addiction Severity Index).

RESULTS

A fall was reported by 35% (87/251) of the sample in Boston and 12% (46/400) in St Petersburg. Each additional AUD criterion-but not higher AUDIT-C score-was significantly associated with a fall in both Boston (odds ratio [OR] = 1.10; 95% confidence interval [CI] 1.02, 1.18) and St Petersburg (adjusted OR AOR = 1.10; 95% CI 1.02, 1.18). Heavy alcohol use (>6 drinks/occasion, any vs. none) was associated with more than twice the odds of a fall (AOR = 2.24; 95% CI 1.21, 4.13) in Boston.

CONCLUSIONS

These findings suggest that while fall risk may vary by setting and population, heavy alcohol use and AUD symptom severity are potential targets for interventions to prevent falls. Studies in diverse global settings advance our understanding of the relationship between alcohol and falls in PWH.

Screening Accuracy of Mini Addenbrooke's Cognitive Examination Test for HIV-Associated Neurocognitive Disorders in People Ageing with HIV

Aging and increased cardiovascular risk are major drivers for HIV-associated neurocognitive disorders (HAND), for which accurate screenings are lacking. Mini-Addenbrooke's Cognitive Examination (MACE) reliably detects vascular and neurodegenerative cognitive decline among HIV-negative patients. We evaluated MACE diagnostic accuracy in detecting HAND in people living with HIV (PLWH) and we compared it with the International HIV Dementia Scale (IHDS). A single-centre double-blind study of diagnostic accuracy on adult outpatient PLWH without neurocognitive confounding was performed. MACE and IHDS were administered in 5 and 10 min by clinicians, followed by the reference standard battery (14 tests) by neuropsychologists. HAND diagnosis was based on the modified version of Frascati's criteria by Gisslén to reduce false positives. Exploratory cut-offs were evaluated for MACE. Diagnostic accuracy and clinical utility parameters were assessed. 231 patients were enrolled. 75.7% men with a median age, education, and length of infection of 54 (48-59), 10 (8-13) and 16 (5-25) years. HAND prevalence was 48.5% (38.9% asymptomatic impairment). Compared to IHDS, MACE sensitivity (89.3% vs 70.5%), specificity (94.1% vs 63.0%), correct classification rate (86.5% vs 66.7%), J index (0.83 vs 0.34), AUROC (0.97 vs 0.79), agreement with the gold standard (k 0.84 vs 0.33) and effect size in distinguishing HAND vs non-HAND (d 2.11 vs 1.15) were higher. Among PLWH aged 65 years and above (n = 37) MACE performance was consistently better than IHDS. The quick and easy-to-perform MACE could possess an accurate and useful screening performance for HAND in otherwise neurocognitively healthy cohorts of PLWH.

HIV-Associated Neurocognitive Disorders: The First Longitudinal Follow-Up of a cART-Treated Cohort of Older People in Sub-Saharan Africa

BACKGROUND

HIV-associated neurocognitive disorders (HAND) are a highly prevalent chronic complication in older people living with HIV (PLWH) in high-income countries. Although sub-Saharan Africa has a newly emergent population of older combination antiretroviral therapy (cART)-treated PLWH, HAND have not been studied longitudinally. We assessed longitudinal prevalence of HAND and have identified possible modifiable factors in a population of PLWH aged 50 years or older, over 3 years of follow-up.

METHODS

Detailed neuropsychological and clinical assessment was completed annually in the period 2016-2019 in a systematic sample of cART-treated PLWH in Kilimanjaro, Tanzania. A consensus panel defined HAND using American Academy of Neurology criteria for asymptomatic neurocognitive impairment, mild neurocognitive disorder, and HIV-associated dementia. HIV disease severity and other factors associated with HAND progression, improvement, and stability were evaluated in individuals fully assessed at baseline and in 2019.

RESULTS

At baseline, 47% of the cohort (n = 253, 72.3% female individuals) met HAND criteria despite good HIV disease control [Y1 59.5% (n = 185), Y2 61.7% (n = 162), and Y3 57.9% (n = 121)]. Of participants fully assessed at baseline and year 3 (n = 121), HAND remained stable in 54% (n = 57), improved in 15% (n = 16), and declined in 31% (n = 33). Older age and lower education level significantly predicted HAND progression, whereas HIV-specific factors did not. Male sex and shorter cART duration were associated with improvement.

CONCLUSIONS

In this first longitudinal study characterizing clinical course of HAND in older cART-treated PLWH in sub-Saharan Africa, HAND was highly prevalent with variable progression and reversibility. Progression may be more related to cognitive reserve than HIV disease in cART-treated PLWH.

Neurological soft signs and brain morphology in people living with HIV

Neurological soft signs (NSS) are a common feature of severe psychiatric disorders such as schizophrenia but are also prevalent in organic brain diseases like HIV-associated neurocognitive disorder (HAND) or Alzheimer’s disease. While distinct associations between NSS, neurocognition, and cerebral regions were demonstrated in schizophrenia, these associations still have to be elucidated in HIV. Therefore, we investigated 36 persons with HIV of whom 16 were neurocognitively healthy and 20 were diagnosed with HAND. NSS were assessed using the Heidelberg scale. NSS scores were correlated with gray matter (GM) using whole brain voxel-based morphometry. Results showed significantly elevated NSS in the HAND group when compared to the neurocognitively healthy with respect to NSS total score and the subscores “orientation” and “complex motor tasks”. While the two groups showed only minor, non-significant GM differences, higher NSS scores (subscales “motor coordination”, “orientation”) were significantly correlated with GM reduction in the right insula and cerebellum (FWE-corrected). Our results corroborate elevated NSS in HIV+ patients with HAND in contrast to cognitively unimpaired patients. In addition, cerebral correlates of NSS with GM reductions in insula and cerebellum were revealed. Taken together, NSS in this patient group could be considered a marker of cerebral damage and neurocognitive deficits.

The Longitudinal Effects of Blood Pressure and Hypertension on Neurocognitive Performance in People Living With HIV

BACKGROUND

Hypertension (HTN) and HIV are salient risk factors for cerebral small vessel disease and neurocognitive (NC) impairment, yet the effects of HTN on NC performance in persons living with HIV remain poorly understood. This is the first study to examine the longitudinal associations between blood pressure (BP), HTN, and pulse pressure (PP) with NC performance in persons living with HIV.

SETTING

New York City.

METHODS

Analysis of medical, NC, and virologic data from 485 HIV+ participants was collected by the Manhattan HIV Brain Bank, a prospective, observational, longitudinal study of neuroHIV. A series of multilevel linear growth curve models with random intercepts and slopes were estimated for BP, HTN status, and PP to predict the change in NC performance.

RESULTS

The baseline prevalence of HTN was 23%. Longitudinal changes in diastolic and systolic pressure were associated with a 10.5-second and 4-second increase in the Grooved Pegboard Test nondominant hand performance, respectively. A longitudinal change in diastolic BP was also associated with a 0.3-point decline in correct categories and 3-point increase in perseverative responses and total errors on the Wisconsin Card Sorting Test. Increasing odds of prevalent and/or incident HTN were associated with a 0.1-point decrease in correct categories and a 0.8-point increase in total errors on the Wisconsin Card Sorting Test. There was no association between PP and NC performance.

CONCLUSIONS

The results indicate linear longitudinal relations for BP and HTN with poorer NC test performance, particularly in psychomotor and executive functions in persons with HIV.

Role of Brain Arterial Remodeling in HIV-Associated Cerebrovascular Outcomes

As the life expectancy of people living with HIV (PLWH) on combination antiretroviral therapy (cART) increases, so does morbidity from cerebrovascular disease and neurocognitive disorders. Brain arterial remodeling stands out as a novel investigational target to understand the role of HIV in cerebrovascular and neurocognitive outcomes. We therefore conducted a review of publications in PubMed, EMBASE, Web of Science and Wiley Online Library, from inception to April 2021. We included search terms such as HIV, cART, brain, neuroimmunity, arterial remodeling, cerebrovascular disease, and neurocognitive disorders. The literature shows that, in the post-cART era, PLWH continue to experience an increased risk of stroke and neurocognitive disorders (albeit milder forms) compared to uninfected populations. PLWH who are immunosuppressed have a higher proportion of hemorrhagic strokes and strokes caused by opportunistic infection and HIV vasculopathy, while PLWH on long-term cART have higher rates of ischemic strokes, compared to HIV-seronegative controls. Brain large artery atherosclerosis in PLWH is associated with lower CD4 nadir and higher CD4 count during the stroke event. HIV vasculopathy, a form of non-atherosclerotic outward remodeling, on the other hand, is associated with protracted immunosuppression. HIV vasculopathy was also linked to a thinner media layer and increased adventitial macrophages, suggestive of non-atherosclerotic degeneration of the brain arterial wall in the setting of chronic central nervous system inflammation. Cerebrovascular architecture seems to be differentially affected by HIV infection in successfully treated versus immunosuppressed PLWH. Brain large artery atherosclerosis is prevalent even with long-term immune reconstitution post-cART. HIV-associated changes in brain arterial walls may also relate to higher rates of HIV-associated neurocognitive disorders, although milder forms are more prevalent in the post-cART era. The underlying mechanisms of HIV-associated pathological arterial remodeling remain poorly understood, but a role has been proposed for chronic HIV-associated inflammation with increased burden on the vasculature. Neuroimaging may come to play a role in assessing brain arterial remodeling and stratifying cerebrovascular risk, but the data remains inconclusive. An improved understanding of the different phenotypes of brain arterial remodeling associated with HIV may reveal opportunities to reduce rates of cerebrovascular disease in the aging population of PLWH on cART.

Humanized Mice for Infectious and Neurodegenerative disorders

Humanized mice model human disease and as such are used commonly for research studies of infectious, degenerative and cancer disorders. Recent models also reflect hematopoiesis, natural immunity, neurobiology, and molecular pathways that influence disease pathobiology. A spectrum of immunodeficient mouse strains permit long-lived human progenitor cell engraftments. The presence of both innate and adaptive immunity enables high levels of human hematolymphoid reconstitution with cell susceptibility to a broad range of microbial infections. These mice also facilitate investigations of human pathobiology, natural disease processes and therapeutic efficacy in a broad spectrum of human disorders. However, a bridge between humans and mice requires a complete understanding of pathogen dose, co-morbidities, disease progression, environment, and genetics which can be mirrored in these mice. These must be considered for understanding of microbial susceptibility, prevention, and disease progression. With known common limitations for access to human tissues, evaluation of metabolic and physiological changes and limitations in large animal numbers, studies in mice prove important in planning human clinical trials. To these ends, this review serves to outline how humanized mice can be used in viral and pharmacologic research emphasizing both current and future studies of viral and neurodegenerative diseases. In all, humanized mouse provides cost-effective, high throughput studies of infection or degeneration in natural pathogen host cells, and the ability to test transmission and eradication of disease.

Characteristics of Motor Dysfunction in Longstanding Human Immunodeficiency Virus

BACKGROUND

Cognitive dysfunction in human immunodeficiency virus (HIV) has decreased, but milder forms of HIV-associated neurocognitive disorders (HAND) persist along with motor dysfunction. The HIV Motor Scale (HMS) is a validated tool that captures motor abnormalities on routine neurologic examination and which is associated with cognitive impairment in HIV. In this study, we applied a modified HMS (MHMS) to a nationwide cohort of people with longstanding HIV to characterize and understand the factors contributing to motor dysfunction.

METHODS

The National NeuroAIDS Tissue Consortium is a nationwide longitudinal cohort study. Participants undergo regular assessments including neurological examination, neuropsychological testing, and immunovirologic data collection. Data from examinations were used to calculate the MHMS score, which was then correlated with history of AIDS-related central nervous system (CNS) disorders (ARCD; eg, prior CNS opportunistic infection), cerebrovascular disease (CVD), and HAND.

RESULTS

Sixty-nine percent of participants showed an abnormality on the MHMS, with 27% classified as severe. Results did not vary based on demographic or immunologic variables. The most common abnormalities seen were gait (54%), followed by coordination (39%) and strength (25%), and these commonly co-occurred. CVD (P = .02), history of ARCD (P = .001), and HAND (P = .001) were all associated with higher (ie, worse) HMS in univariate analyses; CVD and ARCD persisted in multivariate analyses. CVD was also marginally associated with symptomatic HAND.

CONCLUSIONS

Complex motor dysfunction remains common in HIV and is associated with CVD, ARCD, and to a lesser extent, HAND. Future studies are needed to understand the longitudinal trajectory of HIV-associated motor dysfunction, its neural substrates, and impact on quality of life.

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.

Ineffective health control: concept analysis

OBJECTIVES

to identify and synthesize the concept of Ineffective Health Control.

METHODS

Concept Analysis from the perspective of Walker and Avant, operationalized by an integrative review in the databases Scopus, LILACS, PubMed, CINAHL, Web of Science, Science Direct e Cochrane, using the descriptors: Adhesion to Medication; Cooperation and Adherence to Treatment and Acquired Immunodeficiency Syndrome.

RESULTS

five critical attributes were identified for the concept, namely: patient's refusal to follow the therapeutic plan; abandoning treatment and worsening signs and symptoms; difficulty in reaching agreed goals; difficulty following health professionals' guidelines; multifactorial and dynamic process.

CONCLUSIONS

the concept of Ineffective Health Control is characterized by a multifactorial and dynamic process evidenced by the patient's refusal to follow a therapeutic plan, favouring the abandonment of treatment and resulting in the worsening of signs and symptoms and failure to reach goals.

Robot-Based Assessment of HIV-Related Motor and Cognitive Impairment for Neurorehabilitation

There is a pressing need for strategies to slow or treat the progression of functional decline in people living with HIV. This paper explores a novel rehabilitation robotics approach to measuring cognitive and motor impairment in adults living with HIV, including a subset with stroke. We conducted a cross-sectional study with 21 subjects exhibiting varying levels of cognitive and motor impairment. We tested three robot-based tasks – trajectory tracking, N-back, and spatial span – to assess if metrics derived from these tasks were sensitive to differences in subjects with varying levels of executive function and upper limb motor impairments. We also examined how well these metrics could estimate clinical cognitive and motor scores. The results showed that the average sequence length on the robot-based spatial span task was the most sensitive to differences between various cognitive and motor impairment levels. We observed strong correlations between robot-based measures and clinical cognitive and motor assessments relevant to the HIV population, such as the Color Trails 1 (rho = 0.83), Color Trails 2 (rho = 0.71), Digit Symbol – Coding (rho = 0.81), Montreal Cognitive Assessment – Executive Function subscore (rho = 0.70), and Box and Block Test (rho = 0.74). Importantly, our results highlight that gross motor impairment may be overlooked in the assessment of HIV-related disability. This study shows that rehabilitation robotics can be expanded to new populations beyond stroke, namely to people living with HIV and those with cognitive impairments.

Physical and Mental Health Screening in a New York City HIV Cohort During the COVID-19 Pandemic: A Preliminary Report

BACKGROUND

Mental health consequences of the COVID-19 pandemic have been observed. Psychiatric symptoms in people living with HIV, and their relationship to physical symptomatology and prior psychopathology, are not yet reported.

SETTING

An HIV cohort sheltering-in-place in New York City.

METHODS

Forty-nine participants in a longitudinal study were contacted by telephone in April 2020. A structured interview queried COVID-19-associated physical symptoms, and mental health screens were performed with the generalized anxiety disorder-2 (GAD-2) and patient health questionnaire-2 (PHQ-2). Prior medical and neuropsychiatric data were obtained from preceding study visits. Post-hoc analyses were performed.

RESULTS

The mean age of respondents was 62.1 years, 39% were women, and 35% African American, 37% Latinx, and 28% Caucasian. COVID-19-indicator symptoms were present in 69%; 41% had respiratory and 61% extra-pulmonary symptoms. Mental health symptoms were endorsed in 45% with PHQ-2 and 43% with GAD-2, although threshold for major depression was met in only 4% and for GAD in 14%. Higher PHQ scores were associated with respiratory symptoms, but not prior mood or anxiety disorders. GAD-2 scores were higher with past mood disorders, but not with prior anxiety disorders or respiratory symptoms.

CONCLUSIONS

Physical symptoms were frequent and mild psychiatric symptoms were common, but serious anxiety and depression were not often endorsed by this group of people living with HIV at the acute height of the New York City COVID-19 pandemic. Reasons for this are unclear, as this preliminary report is descriptive in nature. Short- and long-term consequences of acute mental health symptoms require further study.

Cognitive Impairment Among Aging People Living With HIV on Antiretroviral Therapy: A Cross-Sectional Study in Hunan, China

Our cross-sectional study examined the prevalence of cognitive impairment among people living with HIV (PLWH) aged 60 years or older. The sample, composed of 250 PLWH, was recruited from 2 clinics in Hunan, China. Structured questionnaires guided face-to-face interviews, including items addressing demographic characteristics, regimens of antiretroviral therapy, and cognitive status as measured by the Montreal Cognitive Assessment. Findings revealed cognitive function of this population was significantly lower than that of uninfected individuals based on historical comparisons; 87.2% (n = 218) of PLWH in our study had cognitive impairment. Global cognitive function as well as the domains of language and orientation decreased with age. Global cognitive function was associated with sex and education, but not with antiretroviral therapy regimens. These findings support an urgent need to include routine screening for cognitive function in older PLWH and the need to consider the complexity of the evaluation process.

Robot-based assessment of HIV-related motor and cognitive impairment for neurorehabilitation

There is a pressing need for strategies to slow or treat the progression of functional decline in people living with HIV. This paper explores a novel rehabilitation robotics approach to measuring cognitive and motor impairment in adults living with HIV, including a subset with stroke. We conducted a cross-sectional study with 21 subjects exhibiting varying levels of cognitive and motor impairment. We developed three robot-based tasks – trajectory tracking, N-back, and spatial span – to assess if metrics derived from these tasks were sensitive to differences in subjects with varying levels of executive function and upper limb motor impairments. We also examined if these metrics could estimate clinical cognitive and motor scores. The results showed that the average sequence length on the robot-based spatial span task was the most sensitive to differences between subjects’ cognitive and motor impairment levels. We observed strong correlations between robot-based measures and clinical cognitive and motor assessments relevant to the HIV population, such as the Color Trails 1 (rho = 0.83), Color Trails 2 (rho = 0.71), Digit Symbol – Coding (rho = 0.81), Montreal Cognitive Assessment – Executive Function subscore (rho = 0.70), and Box and Block Test (rho = 0.74). Importantly, our results highlight that gross motor impairment may be overlooked in the assessment of HIV-related disability. This study shows that rehabilitation robotics can be expanded to new populations beyond stroke, namely to people living with HIV and those with cognitive impairments.

Cognitive and motor deficits in older adults with HIV infection: Comparison with normal ageing and Parkinson's disease

Despite the life-extending success of antiretroviral pharmacotherapy in HIV infection (HIV), the prevalence of mild cognitive impairment in HIV remains high. Near-normal life expectancy invokes an emerging role for age-infection interaction and a potential synergy between immunosenescence and HIV-related health factors, increasing risk of cognitive and motor impairment associated with degradation in corticostriatal circuits. These neural systems are also compromised in Parkinson's disease (PD), which could help model the cognitive deficit pattern in HIV. This cross-sectional study examined three groups, age 45-79 years: 42 HIV, 41 PD, and 37 control (CTRL) participants, tested at Stanford University Medical School and SRI International. Neuropsychological tests assessed executive function (EF), information processing speed (IPS), episodic memory (MEM), visuospatial processing (VSP), and upper motor (MOT) speed and dexterity. The HIV and PD deficit profiles were similar for EF, MEM, and VSP. Although only the PD group was impaired on MOT compared with CTRL, MOT scores were related to cognitive scores in HIV but not PD. Performance was not related to depressive symptoms, socioeconomic status, or CD4⁺ T-cell counts. The overlap of HIV-PD cognitive deficits implicates frontostriatal disruption in both conditions. The motor-cognitive score relation in HIV provides further support for the hypothesis that these processes share similar underlying mechanisms in HIV infection possibly expressed with or exacerbated by ageing.

Neurological soft signs (NSS) and cognitive deficits in HIV associated neurocognitive disorder

Neurological soft signs (NSS) are frequently found in severe mental disorders, such as Alzheimer's disease, schizophrenia or HIV associated neurocognitive disorder (HAND) which includes asymptomatic neurocognitive impairment (ANI), mild neurocognitive disorder (MND) and HIV-associated dementia. To characterize NSS in patients with HIV we examined them with respect to neuropsychological deficits typically found in the disorder. 67 HIV + patients without a history of head trauma, opportunistic infections, severe psychiatric disorders or acute confounding comorbidities of the Central nervous system (CNS) were recruited. NSS and neuropsychological deficits were examined on the Heidelberg scale and the Cambridge Neuropsychological Test Automated Battery (CANTAB), respectively. Semantic and phonemic verbal fluency were additionally established. According to NIMH and NINDS criteria, 18 patients were diagnosed with ANI and 21 with MND, 28 showed no cognitive deficits. NSS total scores were significantly correlated with several cognitive domains and NSS subscales. These correlations were confirmed when motor performance was entered as a covariate. According to our findings, NSS in HIV positive patients are significantly correlated with deficits in a broad range of neuropsychological domains. Similar findings were reported in schizophrenia, emphasizing the transdiagnostic character of NSS and supporting NSS examination in screening HIV patients for HAND.

Greater Sensorimotor Deficits and Abnormally Lower Globus Pallidus Fractional Anisotropy in HIV+ Women than in HIV+ Men

AIMS

Cognitive impairment may be greater in HIV-positive (HIV+) women than in HIV+ men. Whether sex-specific differences exist in brain microstructure of HIV+ individuals is unknown and was evaluated.

METHOD

39 HIV+ (21 men, 18 women) and 45 seronegative (SN, 20 men, 25 women) participants were assessed with brain diffusion tensor imaging and cognitive assessments (7 neuropsychological domains). Fractional anisotropy (FA) and mean diffusivity (MD) were measured with an automated atlas in selected brain regions. Group comparisons were assessed with linear mixed effects models, with sub-regions and hemisphere (left/right) as repeated factors for each region.

RESULTS

HIV+ women, but not HIV+ men, were slower than sex-matched SN controls on sensorimotor function (Dominant-hand: interaction-p = 0.007; Non-dominant hand: interaction-p = 0.039). Similarly, only HIV+ women had lower FA in the globus pallidus (GP, interaction-p = 0.011). Additionally, regardless of sex, the HIV+ group had poorer Fluency, Speed, and Attention than SN-controls (p = 0.006-0.008), as well as lower FA and higher MD in multiple brain regions (p = <0.001-0.044). Across all participants, performance on Attention was predicted by uncinate-FA (p < 0.001, r = 0.5) and corpus callosum (CC)-FA (p = 0.038, r = 0.23), while the Speed of Information Processing was predicted by CC-FA (p = 0.009, r = 0.3). Furthermore, faster sensorimotor function correlated with higher CC-FA and uncinate-FA in men but not in women (Sex*DTI-interaction-p = 0.03-0.06).

CONCLUSIONS

The relatively poorer sensorimotor function and abnormally lower GP_FA, suggesting lesser neuronal integrity, in HIV+ women demonstrate sex-specific effects from HIV-infection on these measures. These findings may be related to the greater immune activation and neuroinflammation in HIV+ women compared to HIV+ men. Graphical Abstract.

Feasibility and Impact of a Yoga Intervention on Cognition, Physical Function, Physical Activity, and Affective Outcomes among People Living with HIV: A Randomized Controlled Pilot Trial

The purpose of this pilot randomized controlled trial is to assess the feasibility and impact of a triweekly 12-week yoga intervention among people living with HIV (PLWH). Additional objectives included evaluating cognition, physical function, medication adherence, health-related quality of life (HRQoL), and mental health among yoga participants versus controls using blinded assessors. We recruited 22 medically stable PLWH aged ≥35 years. A priori feasibility criteria were ≥70% yoga session attendance and ≥70% of participants satisfied with the intervention using a postparticipation questionnaire. Two participants withdrew from the yoga group. Mean yoga class attendance was 82%, with 100% satisfaction. Intention-to-treat analyses (yoga n = 11, control n = 11) showed no within- or between-group differences in cognitive and physical function. The yoga group improved over time in HRQoL cognition (P = .047) with trends toward improvements in HRQoL health transition (P =.063) and depression (P = .055). This pilot study provides preliminary evidence of feasibility and benefits of yoga for PLWH.

The impact of HIV central nervous system persistence on pathogenesis

: The persistence of HIV in the central nervous system is somewhat controversial particularly in the context of HIV viral suppression from combined antiretroviral therapy. Further, its significance in relation to HIV pathogenesis in the context of HIV-associated neurocognitive disorders, systemic HIV pathogenesis, and eradication in general, but especially from the brain, are even more contentious. This review will discuss each of these aspects in detail, highlighting new data, particularly from recent conference presentations.

Frailty in medically complex individuals with chronic HIV

OBJECTIVES

Multimorbidity and frailty are consequences of aging with HIV, yet not everyone with medical disease is frail. Our objective was to identify factors associated with frailty in a multimorbid HIV-infected cohort.

DESIGN

Analysis of a prospective, observational, longitudinal cohort.

METHODS

Three hundred and thirty-two participants in the medically advanced National NeuroAIDS Tissue Consortium (NNTC) study were categorized as frail, prefrail, or robust with the Fried Frailty Index. A series of logistic regression analyses (first univariate, then multivariable) were conducted to determine whether medical comorbidities, immunologic and virologic parameters, and/or neuropsychiatric variables predicted increased odds of frailty.

RESULTS

The mean number of medical comorbidities per participant was 2.7, mean CD4 T-cell count was 530 cells/μl, and 77% had undetectable HIV RNA in blood. Twenty-two percent were frail, 55% prefrail, and 23% robust. Significant predictors of frailty in multivariable analysis were cognitive diagnosis rendered by Frascati criteria, depressive symptoms, diabetes mellitus, chronic obstructive pulmonary disease (COPD), and sex. Men were less likely to be frail than women. Higher odds of frailty were seen with: symptomatic, but not asymptomatic, cognitive impairment (compared with cognitive normals); more depressive symptoms; diabetes mellitus; and COPD.

CONCLUSION

Neuropsychiatric illness increased odds of being frail on a predominantly physical/motoric measure, but only when symptomatic. Lack of association with asymptomatic impairment may reflect the importance of functional limitation to frailty, or possibly a unique resilience phenotype. Understanding why sex and symptomatic neuropsychiatric illness are associated with frailty will be important in managing HIV-associated morbidity in aging populations.

Various associations of aging and long-term HIV infection with different neurocognitive functions: detailed analysis of a Japanese nationwide multicenter study

Detailed information of the effects of age and long-term HIV infection on various neurocognitive function have not been fully evaluated yet. In a prospective Japanese nationwide multicenter study of 17 facilities (J-HAND study), 728 HIV-infected individuals completed 14 neuropsychological (NP) tests; Verbal Fluency (VF; category and letter), Digit Span (DS; forward and backward), Trail Making Test (TMT) A-B, Rey-Osterrieth Complex Figure Test (ROCFT; copy, immediate and delayed recall), Story Memory Test (SMT; immediate and delayed recall), Digit Symbol Subset (DSS), and the Grooved Pegboard (GP; dominant and non-dominant). Multivariate analysis identified older age (≥ 50 years) to be associated with lower scores in all three ROCFT and GP dominant [odds ratio (OR) [95% confidence interval (CI)] 1.801 (1.217-2.664), 2402 (1.366-3.055), 2.691 (1.720-4.211), and 2.302 (1.145-4.628), respectively], whereas longer time since diagnosis was associated with a lower score in ROCFT (delayed recall) (OR 1.224, 95%CI 1.045-1.434). In VF letter, older age and longer time since diagnosis were associated with a better score [OR (95%CI) 0.449 (0.234-0.861) and 0.831 (0.692-0.997)]. In DSS and TMT-A, longer time since diagnosis was associated with a better score [OR (95%CI): 0.808 (0.670-0.973) and 0.795 (0.665-0.949), respectively]. Older patients in later years since diagnosis are at higher risk of visuospatial and motor impairments despite ART, whereas they are less likely to develop verbal impairment, suggesting that verbal function is relatively resistant to aging and long history of HIV infection under ART. These findings suggest that customtailored supports should be established based on the individual background.

Reliably Measuring Cognitive Change in the Era of Chronic HIV Infection and Chronic HIV-Associated Neurocognitive Disorders

HIV infection has become a chronic disease managed across the life span. In this context, the cognitive health of HIV infection needs to have methods for monitoring over time, in order to better anticipate HIV-associated neurocognitive disorder (HAND) trajectories in relation to biomarkers, and predict prognosis and especially the risk of dementia as People Living with HIV (PLHIV) age. In this chapter, we critically review several statistical frameworks to quantify cognitive change. We then provide a critical review of naturalistic longitudinal studies and selected randomized clinical trials assessing neurocognitive change as a primary outcome in PLHIV, conducted since the advent of the combined antiretroviral therapy era (censored January 2019). Doing so, we distinguish between PLHIV who were treated early and did not experience AIDS (CDC 1993), versus treated late, after experiencing AIDS and more severe immune compromise. Highlighting strengths and limitations of these studies, we emphasize that issues of reliability pertaining to the use of neuropsychological tests need careful consideration for the robust quantification of cognitive change, including measurement error, practice effect, inter-individual variability, baseline level of functioning, demographic effects, timeframe between testing intervals, normative longitudinal data, and operationalization of clinically meaningful neurocognitive change. In addition, issues pertaining to longitudinal analyses including type, amount and pattern of missing data and/or participant attrition, regression toward the mean, and survivor bias need to be properly addressed. We conclude by proposing future research directions with emphasis on research translation to clinical participants.

Extrapyramidal motor signs in older adults with HIV disease: frequency, 1-year course, and associations with activities of daily living and quality of life

Age and HIV disease have additive effects on neural systems that support motor functioning. The current study examined the combined impact of aging and HIV on extrapyramidal motor functions, which were hypothesized to influence on activities of daily living (ADLs) and quality of life (QoL). Participants included 336 adults classified by HIV serostatus and age. A research nurse administered the Unified Parkinson's Disease Rating Scale (UPDRS) and participants completed the modified Lawton & Brody ADL and the Short Form Survey Instrument (SF-36) questionnaires as part of a larger neuropsychological research battery. A convenience subset of 172 participants completed a 14-month follow-up evaluation. At baseline, only older age was associated with mild extrapyramidal signs; however, at 14-month follow-up, independent adverse effects of both HIV status and age group were observed on a 3-level UPDRS change variable. Among older HIV+ adults, the presence of mild UPDRS motor signs was independently associated with basic and instrumental ADL dependence, as well as lower physical (ps < .05), but not mental QoL. In the modern treatment era, older HIV+ adults show higher frequency of mild extrapyramidal signs as compared to younger individuals (but not older HIV- persons) and are at higher risk of incident extrapyramidal signs relative to HIV- persons (but not younger HIV+ persons). When present in older HIV+ adults, extrapyramidal signs are of mild severity but nevertheless increase the risk of daily functioning problems and lower health-related physical QoL.