Interaction Effects between HIV and Aging on Selective Neurocognitive Impairment

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.

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.

Outcome of Lenalidomide Treatment for Cognitive Impairment Caused by Immune Reconstitution Inflammatory Syndrome in Patients with HIV-Related Cryptococcal Meningitis

Purpose

Cognitive impairment associated with human immunodeficiency virus (HIV)-related cryptococcal meningitis (HCM) in the context of immune reconstitution inflammatory syndrome is difficult to address. This study was a follow-up of lenalidomide treatment outcomes in patients with HCM and cognitive impairment after complete cryptococcal clearance.

Patients and Methods

Seven HCM patients with neuroinflammation and cognitive impairment after complete cryptococcal clearance were enrolled in this prospective study. Neurocognitive assessment, clinical examination and cerebrospinal fluid (CSF) assays were performed before and after lenalidomide treatment.

Results

After lenalidomide treatment, the Montreal Cognitive Assessment [week (W) 0 (median [interquartile range]: 23.0 (13.0–24.0) vs W24: 26.0 (24.0–28.00), P=0.018] and International HIV Dementia Scale scores [W0: 9.0 (2.5–10.5) vs W24: 11.0 (10.00–12.0), P=0.028] improved significantly, mainly in the domain of memory function. There was no significant difference in the Center for Epidemiological Research Depression scores for anxiety and depression before and after treatment. Further stratified analyses revealed that the patients with cognitive improvement group had higher levels of CSF white blood cells [94.0 (44.0–180.0) vs 0 (0–1.5), P=0.032], CSF protein [4.9 (3.0–6.6) vs 0.6 (0.5–0.7), P=0.034], CSF albumin [318.5 (190.9–346.5) vs 33.5 (30.4–46.2), P=0.034], and CSF IgG [160.5 (73.8–256. 0) vs 4.7 (4.3–7.4), P=0.034] but a lower CSF glucose level [2.4 (2.0–2.7) vs 2.8 (2.8–3.9), P=0.032] than the patients with cognitive non-improvement group before treatment. CSF inflammatory cytokines of the growth-related oncogene, interleukin [IL]-10, granulocyte-colony stimulating factor, IL-6, IL-8, complement factor H, tumor necrosis factor-α, and α-2 macroglobulin were obviously decreased in patients with cognitive improvement group after lenalidomide treatment.

Conclusion

Lenalidomide potentially reduces cognitive impairment caused by immune reconstitution inflammatory syndrome in patients with HCM after cryptococcal clearance by inhibiting intracranial inflammation.

Association between human herpesvirus 6 (HHV-6) and cognitive function in the elderly population in Shenzhen, China

AIM

Human herpesvirus 6 (HHV-6) is neurophilic, and its relationship with Alzheimer's disease (AD) remains controversial. This study aimed to examine the relationships between HHV-6 and cognitive abilities in elderly people aged 60 years or above from communities in Shenzhen.

METHODS

We recruited participants from 10 community health service centers in Shenzhen. Participants were divided into case and control groups according to Mini-Mental State Examination (MMSE) scale standards and were included in this study with 1:1 matching based on sex and age (± 3 years). The HHV-6 gene was detected by real-time fluorescent quantitative PCR, and the HHV-6 copy number was quantified.

RESULTS

A total of 580 participants (cases, n = 290; controls, n = 290), matched for gender and age was included in this study. A positive HHV-6 test was not associated with a significant difference in global cognitive performance (OR_adjusted = 1.651, 95% CI = 0.671-4.062). After adjusting for gender, age, education, Pittsburgh Sleep Quality Index (PSQI) score, homocysteine (Hcy) and glycosylated hemoglobin (HbA1c), the results of multiple linear regression showed that there was a statistically negative correlation between HHV-6 copy number and orientation (β_adjusted = -0.974, p = 0.013), attention and calculation (β_adjusted = -1.840, p < 0.001), and language (β_adjusted = -2.267, p < 0.001). The restricted cubic spline (RCS) model results showed that there was a nonlinear dose-response relationship between HHV-6 log10-transformed copies and orientation (p_overall = 0.003, p_nonliner = 0.045), attention and calculation (p_overall < 0.001, p_nonliner < 0.001), and language (p_overall < 0.001, p_nonliner = 0.016).

CONCLUSIONS

HHV-6 infection significantly associated with orientation, attention and calculation, and language in elderly individuals.

From surviving to thriving: the current status of the behavioral, social, and psychological issues of aging with HIV

PURPOSE OF REVIEW

Despite significant advances in knowledge regarding the biological and clinical issues related to aging with HIV, significantly less research has centered on related psychological, behavioral, and social issues, which are increasingly recognized as important for successfully aging with HIV.

RECENT FINDINGS

Barriers to successful aging include physical challenges from a sociobehavioral perspective, psychosocial challenges, and system-level challenges. In contrast, several resiliencies and interventions that help facilitate healthy aging with HIV are also emerging. Comprehensive interventions to address the physical, mental, and psychosocial needs of older people living with HIV (OPLWH) are necessary.

CONCLUSION

To promote healthy aging with HIV, we must utilize both clinical and biopsychosocial interventions. The lack of data on the needs of OPLWH is an important barrier to healthy aging in this population.

Effects of Docosahexanoic Acid on Gut Microbiota and Fecal Metabolites in HIV-Infected Patients With Neurocognitive Impairment: A 6-Month Randomized, Double-Blind, Placebo-Controlled Trial

Neurocognitive impairment (NCI) and gut microbiota dysbiosis are prevalent in patients with HIV infection. Docosahexanoic acid (DHA) supplementation may alleviate multiple neurocognitive diseases symptoms and plays important role in regulating gut microbiota. However, it is not known whether DHA algae oil supplements can alleviate neurocognitive impairment (NCI) and regulate gut microbiota and fecal metabolites. A randomized, double-blind, placebo-controlled trial was performed on 68 HIV-infected patients with NCI. Participants were randomized to receive a 3.15 g daily DHA algae oil supplement or placebo for 6 months. We collected blood and fecal samples from these patients before and after the trial. Mini mental state examination (MMSE) and neuropsychological tests (NP tests) were administered to assess the cognitive status of participants. The influence of DHA algae oil on the gut microbiota, fecal metabolomics, plasma proinflammatory, and oxidative stress factors was also investigated. There were no significant changes in NCI according to global diagnosis score (GDS) and MMSE score within the two groups, while patients receiving DHA had improvement in several blood lipids, pro-inflammatory and oxidative stress factors. The DHA supplement increased α-diversity indexes, increased abundances of Blautia, Bifidobacterium, Dorea, Lactobacillus, Faecalibacterium, Fusobacterium, and Agathobacter, and decreased abundances of Bacteroides and Prevotella_9. Furthermore, DHA supplement was correlated with improved fecal lipid metabolites as indicated by ceramides, bile acids, glycerophospholipids. In addition, the DHA supplement was associated with altered cholesterol metabolism and purine metabolism pathways. A daily supplement of DHA algae oil for 6 months has been shown to promote favorable transformations in gut microbiota, profiles of fecal metabolomic, and factors responsible for proinflammatory and oxidative stress, which might be beneficial for the prognosis of HIV-infected patients with NCI in the long-term.

Gut Microbiota and Fecal Metabolites Associated With Neurocognitive Impairment in HIV-Infected Population

Gut microbiota dysbiosis has been associated with many neurological diseases. However, how microbiota composition and metabolism relate to neurocognitive impairment (NCI) in HIV-infected individuals is largely unknown. In this study, a total of 102 HIV infected participants were classified into two groups—those with NCI and those without—using the global deficit score (GDS). Fecal samples were collected from the participants for 16S rRNA gene sequencing and untargeted metabolomics. The plasma level of 25 hydroxy-vitamin D (25(OH)D) was also evaluated. Although α-diversity and β-diversity were comparable, the HIV patients with NCI were significantly different from those without NCI in terms of abundance of several gut microbiota. The decreased abundance of butyrate-producing bacteria (BPB) and increased abundance of Klebsiella were related with NCI and carotid intima-media thickness (CIMT). Significant differences in fecal metabolites were also found between individuals with versus without NCI, including increased bile acids and bioactive lipids, decreased vitamin D, terpenoids, and resolvin D1 in the NCI group. Furthermore, the perturbed metabolic profile was closely related to BPB and Klebsiella. In addition, a low level of vitamin D was associated with NCI and CIMT. Both fecal and plasma vitamin D were positively correlated with BPB. Our results show that BPB and Klebsiella and the associated metabolites are associated with NCI in people with HIV. In addition, vitamin D, both in feces and blood, was associated with NCI and BPB, suggesting a protective effect of vitamin D on NCI.

Current Considerations for Clinical Management and Care of People with HIV: Findings from the 11th Annual International HIV and Aging Workshop

The number of people with HIV (PWH) aged 50 years or older continues to steadily increase. The convergence of age- and HIV-related complications in these individuals presents a challenge for both patients and clinicians alike. New findings continue to emerge, as numerous researchers evaluate the combined impact of these two factors on quality of life, physiological systems, and mental health in PWH. Since its first occurrence in 2009, the International Workshop on HIV and Aging has served as a multidisciplinary meeting to share basic biomedical data, clinical trial results, treatment strategies, and epidemiological recommendations, toward better understanding and outcomes among like-minded scientific professionals. In this article, we share a selection of key findings presented in plenary talks at the 11th Annual International Workshop on HIV and Aging, held virtually from September 30, 2020 to October 2, 2020. We will also address the future directions of HIV and aging research, to further assess how the aging process intersects with chronic HIV.

Comprehensive metabolomics profiling reveals common metabolic alterations underlying the four major non-communicable diseases in treated HIV infection

Background

HIV infection and normal aging share immune and inflammatory changes that result in premature aging and non-communicable diseases (NCDs), but the exact pathophysiology is not yet uncovered. We identified the common metabolic pathways underlying various NCDs in treated HIV infection.

Methods

We performed untargeted metabolomics including 87 HIV-negative (–) normal controls (NCs), 87 HIV-positive (+) NCs, and 148 HIV+ subjects with only one type of NCDs, namely, subclinical carotid atherosclerosis, neurocognitive impairment (NCI), liver fibrosis (LF) and renal impairment. All HIV+ subjects were virally suppressed.

Results

HIV+ patients presented widespread alterations in cellular metabolism compared to HIV– NCs. Glycerophospholipid (GPL) metabolism was the only one disturbed pathway presented in comparisons including HIV– NCs across age groups, HIV+ NCs across age groups, HIV+ NCs vs HIV– NCs and each of HIV+ NCDs vs HIV+ NCs. D-glutamine and D-glutamate metabolism and alanine-aspartate-glutamate metabolism were presented in comparisons between HIV+ NCs vs HIV– NCs, HIV+ LF or HIV+ NCI vs HIV+ NCs. Consistently, subsequent analysis identified a metabolomic fingerprint specific for HIV+ NCDs, containing 42 metabolites whose relative abundance showed either an upward (mainly GPL-derived lipid mediators) or a downward trend (mainly plasmalogen phosphatidylcholines, plasmalogen phosphatidylethanolamines, and glutamine) from HIV– NCs to HIV+ NCs and then HIV+ NCDs, reflecting a trend of increased oxidative stress.

Interpretation

GPL metabolism emerges as the common metabolic disturbance linking HIV to NCDs, followed by glutamine and glutamate metabolism. Together, our data point to the aforementioned metabolisms and related metabolites as potential key targets in studying pathophysiology of NCDs in HIV infection and developing therapeutic interventions.

Funding

China National Science and Technology Major Projects on Infectious Diseases, National Natural Science Foundation of China, Yi-wu Institute of Fudan University, and Shanghai Municipal Health and Family Planning Commission.

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.

Association between HIV infection and hypertension: a global systematic review and meta-analysis of cross-sectional studies

BACKGROUND

Improved access to effective antiretroviral therapy has meant that people living with HIV (PLHIV) are surviving to older ages. However, PLHIV may be ageing differently to HIV-negative individuals, with dissimilar burdens of non-communicable diseases, such as hypertension. While some observational studies have reported a higher risk of prevalent hypertension among PLHIV compared to HIV-negative individuals, others have found a reduced burden. To clarify the relationship between HIV and hypertension, we identified observational studies and pooled their results to assess whether there is a difference in hypertension risk by HIV status.

METHODS

We performed a global systematic review and meta-analysis of published cross-sectional studies that examined hypertension risk by HIV status among adults aged > 15 (PROSPERO: CRD42019151359). We searched MEDLINE, EMBASE, Global Health and Cochrane CENTRAL to August 23, 2020, and checked reference lists of included articles. Our main outcome was the risk ratio for prevalent hypertension in PLHIV compared to HIV-negative individuals. Summary estimates were pooled with a random effects model and meta-regression explored whether any difference was associated with study-level factors.

RESULTS

Of 21,527 identified studies, 59 were eligible (11,101,581 participants). Crude global hypertension risk was lower among PLHIV than HIV-negative individuals (risk ratio 0.90, 95% CI 0.85-0.96), although heterogeneity between studies was high (I² = 97%, p < 0.0001). The relationship varied by continent, with risk higher among PLHIV in North America (1.12, 1.02-1.23) and lower among PLHIV in Africa (0.75, 0.68-0.83) and Asia (0.77, 0.63-0.95). Meta-regression revealed strong evidence of a difference in risk ratios when comparing North American and European studies to African ones (North America 1.45, 1.21-1.74; Europe 1.20, 1.03-1.40).

CONCLUSIONS

Our findings suggest that the relationship between HIV status and prevalent hypertension differs by region. The results highlight the need to tailor hypertension prevention and care to local contexts and underscore the importance of rapidly optimising integration of services for HIV and hypertension in the worst affected regions. The role of different risk factors for hypertension in driving context-specific trends remains unclear, so development of further cohorts of PLHIV and HIV-negative controls focused on this would also be valuable.

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.

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

OBJECTIVES

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

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

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

Neurocognitive status and risk of mortality among people living with human immunodeficiency virus: an 18-year retrospective cohort study

HIV-related neurocognitive impairment (NCI) may increase the risk of death. However, a survival disadvantage for patients with NCI has not been well studied in the post-combination antiretroviral therapy (cART) era. Specifically, limited research has been conducted considering the reversible nature and variable progression of the impairment and this area demands further evaluation. We performed multivariable Cox proportional hazards modeling to assess the association between baseline NCI (global T scores) and mortality. A joint modeling approach was then used to model the trajectory of global neurocognitive functioning over time and the association between neurocognitive trajectory and mortality. Among the National NeuroAIDS Tissue Consortium's (NNTC) HIV-infected participants, we found a strong negative association between NCI and mortality in the older age groups (e.g., at age = 55, HR = 0.79; 95% CI 0.64-0.99). Three neurocognitive sub-domains (abstraction and executive functioning, speed of information processing, and motor) had the strongest negative association with mortality. Joint modelling indicated a 33% lower hazard for every 10-unit increase in global T scores (HR = 0.67; 95% CI 0.56-0.80). The study identified older HIV-infected individuals with NCI as a group needing special attention for the longevity of life. The study has considerable prognostic utility by not only predicting mortality hazard, but also future cognitive status.

Association between education level and HIV-associated neurocognitive disorder: a systematic review and meta-analysis

In the era of antiretroviral treatment, human immunodeficiency virus (HIV)-associated neurocognitive disorder (HAND) is common in HIV-positive (HIV+) patients, with an incidence of 30-50%. The relationship between education level and HAND has been evaluated in some studies, however, the results were inconsistent. The aim of this meta-analysis was to provide compelling evidence on the association between education level and the risk of HAND. Reports were searched for in the databases of Medline, Embase and PsyclNFO. Studies evaluating the relationship between education level and HAND in adult HIV+ patients were included. The pooled odds ratio/risk ratio was analysed by using the random-effects model. Two subgroup analyses were performed according to the adjustment of educational level in the neurocognitive impairment assessment and the income level. In total, 18 studies were included. Six studies and 12 studies reported education level as the continuous variable and categorical variable, respectively. The methods used for the assessment of neurocognitive impairment in included studies were neuropsychological battery tests (n = 10), HIV Dementia Scale (n = 1), the International HIV Dementia Scale (n = 6) and the Chinese version of the Montreal Cognitive Assessment (n = 1). The result showed that the risk of HAND in HIV+ patients who have lower education attainment was significantly higher than that in HIV+ patients who have higher education attainment. In conclusion, this meta-analysis demonstrated that HIV+ patients who have low education attainment carry higher risk of developing HAND compared with HIV+ patients who have high education attainment. This study highlighted the importance of early neurological screening for HIV+ patients who have low education level.

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.

HIV and Aging in Mainland China: Implications for Control and Prevention Research

PURPOSE OF REVIEW

The last 15 years have witnessed a dramatic change in HIV-related epidemiology amidst improvements in treatment and care in China. With proper treatment, HIV is now considered a chronic disease. As a consequence, many people living with HIV (PLWH) now present age-related comorbidities. We reviewed 13 topical issues concerning the epidemiology of aging with HIV in mainland China.

RESULTS

Many of aging-related issues associated with the biological and physical aspects of living with HIV addressed in mainland China are consistent with the global literature. Greater prevalence of age-related comorbidities among PLWH was observed. Beyond biological mechanisms associated with HIV infection and traditional risk factors, other factors play a vital role in the aging process among PLWH. A stronger focus on screening, prevention, and management of non-HIV co-morbidities among PLWH is now warranted. Macro-social factors need to be integrated into next generation of clinical and/or behavioral HIV research to inform disease progression and management as well as prevention.

Cognitive Trajectory Phenotypes in Human Immunodeficiency Virus-Infected Patients

OBJECTIVE

The presentation of cognitive impairments in HIV-infected individuals has transformed since the introduction of antiretroviral therapies. Although the overall prevalence of cognitive impairments has not changed considerably, frank dementia is now infrequent, and milder forms of cognitive impairments predominate. Mechanistic insights to the underlying causes of these residual cognitive impairments have been elusive, in part due to the heterogenous etiology of cognitive dysfunction in this population. Here, we sought to categorize longitudinal change in HIV-infected patients based on the performance in specific cognitive domains.

DESIGN

This study consisted of 193 participants from the CHARTER cohort with detailed demographic, clinical, and neuropsychological testing data obtained from 2 study visits interspersed by ∼6 months. Cognitive testing assessed executive function, learning and delayed recall, working memory, verbal fluency, speed of information processing, and motor skills. Change scores were calculated for each domain between the 2 study visits. Dimension reduction and clustering was accomplished by principal component analysis of change scores and k-means clustering to identify cognitive domains that group together and groups of subjects with similar patterns of change.

RESULTS

We identified 4 distinct cognitive change phenotypes that included declines in: (1) verbal fluency, (2) executive function (3) learning and recall, and (4) motor function, with approximately equal numbers of participants in each phenotype.

CONCLUSIONS

Each of the 4 cognitive change phenotypes identify deficits that imply perturbations in specific neural networks. Future studies will need to validate if cognitive change phenotypes are associated with alterations in associated neural pathways.

Progressive brain atrophy in chronically infected and treated HIV+ individuals

Growing evidence points to persistent neurological injury in chronic HIV infection. It remains unclear whether chronically HIV-infected individuals on combined antiretroviral therapy (cART) develop progressive brain injury and impaired neurocognitive function despite successful viral suppression and immunological restoration. In a longitudinal neuroimaging study for the HIV Neuroimaging Consortium (HIVNC), we used tensor-based morphometry to map the annual rate of change of regional brain volumes (mean time interval 1.0 ± 0.5 yrs), in 155 chronically infected and treated HIV+ participants (mean age 48.0 ± 8.9 years; 83.9% male) . We tested for associations between rates of brain tissue loss and clinical measures of infection severity (nadir or baseline CD4+ cell count and baseline HIV plasma RNA concentration), HIV duration, cART CNS penetration-effectiveness scores, age, as well as change in AIDS Dementia Complex stage. We found significant brain tissue loss across HIV+ participants, including those neuro-asymptomatic with undetectable viral loads, largely localized to subcortical regions. Measures of disease severity, age, and neurocognitive decline were associated with greater atrophy. Chronically HIV-infected and treated individuals may undergo progressive brain tissue loss despite stable and effective cART, which may contribute to neurocognitive decline. Understanding neurological complications of chronic infection and identifying factors associated with atrophy may help inform strategies to maintain brain health in people living with HIV.

Baseline Neurocognitive Functioning Predicts Viral Load Suppression at 1-Year Follow-Up Among Newly Diagnosed HIV Infected Patients

The current prospective observational study evaluated the impact of baseline neurocognitive impairment on future viral load suppression among antiretroviral medication naive persons newly diagnosed with HIV infection. We used the Montreal Cognitive Assessment (MoCA) score less than 26, to identify patients with neurocognitive deficits. Of the 138 patients enrolled; virologic suppression was seen in 61% of the participants, while 72% of the participants had a MoCA score less than 26 at baseline. Variables significantly associated with low MoCA score included higher age (p < 0.01) and presence of depression (p < 0.01). After adjusting for these variables, MoCA score less than 26 was significantly associated with a higher risk of failing achieve viral load suppression (adjusted OR 2.7; 95% CI 1.09-6.69). Baseline neurocognitive deficit as measured by MoCA was associated with a higher risk for failing to achieve viral load suppression at one-year follow-up.

Redefining Aging in HIV Infection Using Phenotypes

Purpose of review

This article critically reviews the utility of “phenotypes” as behavioral descriptors in aging/HIV research that inform biological underpinnings and treatment development. We adopt a phenotypic redefinition of aging conceptualized within a broader context of HIV infection and of aging. Phenotypes are defined as dimensions of behavior, closely related to fundamental mechanisms, and, thus, may be more informative than chronological age. Primary emphasis in this review is given to comorbid aging and cognitive aging, though other phenotypes (i.e., disability, frailty, accelerated aging, successful aging) are also discussed in relation to comorbid aging and cognitive aging.

Recent findings

The main findings that emerged from this review are as follows: (1) the phenotypes, comorbid aging and cognitive aging, are distinct from each other, yet overlapping; (2) associative relationships are the rule in HIV for comorbid and cognitive aging phenotypes; and (3) HIV behavioral interventions for both comorbid aging and cognitive aging have been limited.

Summary

Three paths for research progress are identified for phenotype-defined aging/HIV research (i.e., clinical and behavioral specification, biological mechanisms, intervention targets), and some important research questions are suggested within each of these research paths.

HIV-associated neurocognitive disorder

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

HIV-associated executive dysfunction in the era of modern antiretroviral therapy: A systematic review and meta-analysis

OBJECTIVE

While some reports suggest that HIV+ individuals continue to display executive function (EF) impairment in the era of cART, findings have been contradictory and appear to differ based on the aspect of EF being measured. To improve the understanding of how discrete executive abilities may be differentially affected or spared in the context of HIV infection, we conducted a systematic review and meta-analysis to (a) determine whether and to what extent HIV+ adults experience deficits in EFs, and (b) understand how demographic and clinical characteristics may modify the associations between HIV infection and executive abilities.

METHOD

Studies comparing HIV+ and HIV-uninfected groups on measures of working memory, set-shifting, inhibition, decision-making, and apathy between 2000 and 2017 were identified from three databases. Effect sizes (Cohen's d) were calculated using inverse variance weighted random effects models. Meta-regression was used to examine the moderating effect of demographic and clinical variables.

RESULTS

Thirty-seven studies (n = 3935 HIV+; n = 2483 HIV-uninfected) were included in the meta-analysis. Pooled effect sizes for deficits associated with HIV infection were small for domains of set-shifting (d = -0.34, 95% CI [-0.47, -0.20]) and inhibition (d = -0.31, 95% CI [-0.40, -0.21]), somewhat larger for measures of decision-making (d = -0.41, 95% CI [-0.53, -0.28]) and working memory (d = -0.42, 95% CI [-0.59, -0.29]), and largest for apathy (d = -0.87, 95% CI [-1.09, -0.66]). Meta-regression demonstrated that age, sex, education, current CD4 count, and substance dependence differentially moderated the effects of HIV infection on specific EFs. However, lower nadir CD4 count was the only variable associated with greater deficits in nearly all EF domains.

CONCLUSIONS

Our results suggest that discrete domains of EF may be differentially affected by HIV infection and moderating demographic and clinical variables. These findings have implications for the development of targeted cognitive remediation strategies.