Vascular endothelial growth factor receptor 1 gene (FLT1) longevity variant increases lifespan by reducing mortality risk posed by hypertension

Longevity is written into the genes. While many so-called "longevity genes" have been identified, the reason why particular genetic variants are associated with longer lifespan has proven to be elusive. The aim of the present study was to test the hypothesis that the strongest of 3 adjacent longevity-associated single nucleotide polymorphisms - rs3794396 - of the vascular endothelial growth factor receptor 1 gene, FLT1, may confer greater lifespan by protecting against mortality risk from one or more adverse medical conditions of aging - namely, hypertension, coronary heart disease (CHD), stroke, and diabetes. In a prospective population-based longitudinal study we followed 3,471 American men of Japanese ancestry living on Oahu, Hawaii, from 1965 until death or to the end of December 2019 by which time 99% had died. Cox proportional hazards models were used to assess the association of FLT1 genotype with longevity for 4 genetic models and the medical conditions. We found that, in major allele recessive and heterozygote disadvantage models, genotype GG ameliorated the risk of mortality posed by hypertension, but not that posed by having CHD, stroke or diabetes. Normotensive subjects lived longest and there was no significant effect of FLT1 genotype on their lifespan. In conclusion, the longevity-associated genotype of FLT1 may confer increased lifespan by protecting against mortality risk posed by hypertension. We suggest that FLT1 expression in individuals with longevity genotype boosts vascular endothelial resilience mechanisms to counteract hypertension-related stress in vital organs and tissues.

Weak Social Networks in Late Life Predict Incident Alzheimer's Disease: The Kuakini Honolulu-Asia Aging Study

BACKGROUND

We assessed 10-year longitudinal associations between late-life social networks and incidence of all-cause dementia (ACD), Alzheimer's disease (AD), and vascular dementia (VaD) in Japanese-American men.

METHODS

We prospectively analyzed, from baseline (1991-1993) through 1999-2000, 2636 initially nondemented Kuakini Honolulu-Asia Aging Study participants who remained dementia-free during the first 3 years of follow-up. Global cognition was evaluated by the Cognitive Abilities Screening Instrument (CASI); depressive symptoms by the 11-item Center for Epidemiologic Studies Depression (CES-D) Scale; and social networks by the Lubben Social Network Scale (LSNS). Median split of LSNS scores defined weak/strong social network groups. A panel of neurologists and geriatricians diagnosed and classified dementia; AD and VaD diagnoses comprised cases in which AD or VaD, respectively, were considered the primary cause of dementia.

RESULTS

Median (range) baseline age was 77 (71-93) years. Participants with weak (LSNS score ≤29) versus strong (>29) social networks had higher age-adjusted incidence (in person-years) of ACD (12.6 vs. 8.7; p = .014) and AD (6.7 vs. 4.0; p = .007) but not VaD (2.4 vs. 1.4; p = .15). Kaplan-Meier curves showed a lower likelihood of survival free of ACD (log-rank p < .0001) and AD (p = .0006) for men with weak networks. In Cox proportional hazards models adjusting for age, education, APOE ɛ4, prevalent stroke, depressive symptoms, and CASI score (all at baseline), weak networks predicted increased incidence of ACD (hazard ratio [HR] = 1.52, p = .009) and AD (HR = 1.67, p = .014) but not VaD (p > .2).

CONCLUSION

Weak social networks may heighten the risk of dementia and AD, underscoring the need to promote social connectedness in older adults.

Incidence of Alzheimer's Disease in Men with Late-Life Hypertension Is Ameliorated by FOXO3 Longevity Genotype

BACKGROUND

It is well established that mid-life hypertension increases risk of dementia, whereas the association of late-life hypertension with dementia is unclear.

OBJECTIVE

To determine whether FOXO3 longevity-associated genotype influences the association between late-life hypertension and incident dementia.

METHODS

Subjects were 2,688 American men of Japanese ancestry (baseline age: 77.0±4.1 years, range 71-93 years) from the Kuakini Honolulu Heart Program. Status was known for FOXO3 rs2802292 genotype, hypertension, and diagnosis of incident dementia to 2012. Association of FOXO3 genotype with late-life hypertension and incident dementia, vascular dementia (VaD) and Alzheimer's disease (AD) was assessed using Cox proportional hazards models.

RESULTS

During 21 years of follow-up, 725 men were diagnosed with all-cause dementia, 513 with AD, and 104 with VaD. A multivariable Cox model, adjusting for age, education, APOEɛ4, and cardiovascular risk factors, showed late-life hypertension increased VaD risk only (HR = 1.71, 95% CI = 1.08-2.71, p = 0.022). We found no significant protective effect of FOXO3 longevity genotype on any type of dementia at the population level. However, in a full Cox model adjusting for age, education, APOEɛ4, and other cardiovascular risk factors, there was a significant interaction effect of late-life hypertension and FOXO3 longevity genotype on incident AD (β= -0.52, p = 0.0061). In men with FOXO3 rs2802292 longevity genotype (TG/GG), late-life hypertension showed protection against AD (HR = 0.72; 95% CI = 0.55-0.95, p = 0.021). The non-longevity genotype (TT) (HR = 1.16; 95% CI = 0.90-1.51, p = 0.25) had no protective effect.

CONCLUSION

This longitudinal study found late-life hypertension was associated with lower incident AD in subjects with FOXO3 genotype.

A 13-Year Time-Lagged Description of General Cognitive and Functional Abilities in Older Men: A Cross-Lagged Panel Model

Objectives: The purpose of this study was to evaluate a cross-lagged panel model of general cognition and functional abilities over 13 years. The goal was to determine whether general cognitive abilities predict or precede functional decline versus functional abilities predicting cognitive decline. Methods: The sample included 3508 men (71-93 years of age at baseline) of the Kuakini Honolulu-Asia Aging Study who were tested repeatedly using a global cognitive test and an assessment of functional capacity. Education and age served as covariates. Cross-lagged models were tested, assessing stationarity of stability and cross-lags. Results: The overall model fit the data well. Cognitive scores had better stability than functional abilities and predicted functional abilities more strongly than functional abilities predicted cognitive scores over time. The strength of all cross-lags increased over time. Discussion: These longitudinal data show that cognitive scores predicted functional decline in a population-based study of older men.

Novel Functional, Health, and Genetic Determinants of Cognitive Terminal Decline: Kuakini Honolulu Heart Program/Honolulu-Asia Aging Study

To investigate interindividual differences in cognitive terminal decline and identify determinants including functional, health, and genetic risk and protective factors, data from the Honolulu Heart Program/Honolulu-Asia Aging Study, a prospective cohort study of Japanese American men, were analyzed. The sample was recruited in 1965-1968 (ages 45-68 years). Longitudinal performance of cognitive abilities and mortality status were assessed from Exam 4 (1991-1993) through June 2014. Latent class analysis revealed 2 groups: maintainers retained relatively high levels of cognitive functioning until death and decliners demonstrated significant cognitive waning several years prior to death. Maintainers were more likely to have greater education, diagnosed coronary heart disease, and presence of the apolipoprotein E (APOE) ε2 allele and FOXO3 G allele (SNP rs2802292). Decliners were more likely to be older and have prior stroke, Parkinson's disease, dementia, and greater depressive symptoms at Exam 4, and the APOE ε4 allele. Findings support terminal decline using distance to death as the basis for modeling change. Significant differences were observed between maintainers and decliners 15 years prior to death, a finding much earlier compared to the majority of previous investigations.

Plasma anti-CD4 IgG is associated with brain abnormalities in people with HIV on antiretroviral therapy

Anti-CD4 IgG autoantibodies have been implicated in CD4⁺ T cell reconstitution failure, leaving people with HIV (PWH) at heightened risk of HIV-associated comorbidities, such as neurocognitive impairment. Seventeen PWH on stable anti-retroviral therapy (ART) and 10 HIV seronegative controls had plasma anti-CD4 IgG antibodies measured by enzyme-linked immunosorbent assay. Neuropsychological (NP) tests assessed cognitive performance, and brain volumes were measured by structural magnetic resonance imaging. Anti-CD4 IgG levels were elevated (p = 0.04) in PWH compared with controls. Anti-CD4 IgG correlated with global NP z-scores (rho = - 0.51, p = 0.04). A relationship was observed between anti-CD4 IgG and putamen (β = - 0.39, p = 0.02), pallidum (β = - 0.38, p = 0.03), and amygdala (β = - 0.42, p = 0.05) regional brain volumes. The results of this study suggest the existence of an antibody-mediated relationship with neurocognitive impairment and brain abnormalities in an HIV-infected population.

Association of Immunosuppression and Viral Load With Subcortical Brain Volume in an International Sample of People Living With HIV

IMPORTANCE

Despite more widely accessible combination antiretroviral therapy (cART), HIV-1 infection remains a global public health challenge. Even in treated patients with chronic HIV infection, neurocognitive impairment often persists, affecting quality of life. Identifying the neuroanatomical pathways associated with infection in vivo may delineate the neuropathologic processes underlying these deficits. However, published neuroimaging findings from relatively small, heterogeneous cohorts are inconsistent, limiting the generalizability of the conclusions drawn to date.

OBJECTIVE

To examine structural brain associations with the most commonly collected clinical assessments of HIV burden (CD4+ T-cell count and viral load), which are generalizable across demographically and clinically diverse HIV-infected individuals worldwide.

DESIGN, SETTING, AND PARTICIPANTS

This cross-sectional study established the HIV Working Group within the Enhancing Neuro Imaging Genetics Through Meta Analysis (ENIGMA) consortium to pool and harmonize data from existing HIV neuroimaging studies. In total, data from 1295 HIV-positive adults were contributed from 13 studies across Africa, Asia, Australia, Europe, and North America. Regional and whole brain segmentations were extracted from data sets as contributing studies joined the consortium on a rolling basis from November 1, 2014, to December 31, 2019.

MAIN OUTCOMES AND MEASURES

Volume estimates for 8 subcortical brain regions were extracted from T1-weighted magnetic resonance images to identify associations with blood plasma markers of current immunosuppression (CD4+ T-cell counts) or detectable plasma viral load (dVL) in HIV-positive participants. Post hoc sensitivity analyses stratified data by cART status.

RESULTS

After quality assurance, data from 1203 HIV-positive individuals (mean [SD] age, 45.7 [11.5] years; 880 [73.2%] male; 897 [74.6%] taking cART) remained. Lower current CD4+ cell counts were associated with smaller hippocampal (mean [SE] β = 16.66 [4.72] mm3 per 100 cells/mm3; P < .001) and thalamic (mean [SE] β = 32.24 [8.96] mm3 per 100 cells/mm3; P < .001) volumes and larger ventricles (mean [SE] β = -391.50 [122.58] mm3 per 100 cells/mm3; P = .001); in participants not taking cART, however, lower current CD4+ cell counts were associated with smaller putamen volumes (mean [SE] β = 57.34 [18.78] mm3 per 100 cells/mm3; P = .003). A dVL was associated with smaller hippocampal volumes (d = -0.17; P = .005); in participants taking cART, dVL was also associated with smaller amygdala volumes (d = -0.23; P = .004).

CONCLUSIONS AND RELEVANCE

In a large-scale international population of HIV-positive individuals, volumes of structures in the limbic system were consistently associated with current plasma markers. Our findings extend beyond the classically implicated regions of the basal ganglia and may represent a generalizable brain signature of HIV infection in the cART era.

Impact of Cannabis Use on Brain Structure and Function in Suppressed HIV Infection

BACKGROUND

Brain atrophy and cognitive deficits persist among individuals with suppressed HIV disease. The impact of cannabis use is unknown.

METHODS

HIV+ and HIV- participants underwent cross-sectional magnetic resonance imaging and neuropsychological testing. Lifetime frequency, duration (years), and recency of cannabis use were self-reported. Relationships of cannabis use to resting-state functional connectivity (RSFC) and to 9 regional brain volumes were assessed with corrections for multiple comparisons. Peripheral blood cytokines and monocyte subsets were measured in the HIV+ group and examined in relation to cannabis exposure.

RESULTS

We evaluated 52 HIV+ [50.8 ± 7.1 years old; 100% on antiretroviral therapy ≥ 3 months; 83% with plasma viral load < 50 copies/mL] and 55 HIV- [54.0 ± 7.5 years old] individuals. Among HIV+ participants, recent cannabis use (within 12 months) was associated with diminished RSFC, including of occipital cortex, controlling for age. Duration of use correlated negatively with volumes of all regions (most strikingly the nucleus accumbens) independently of recent use and intracranial volume. Recent use was associated with larger caudate and white matter volumes and lower soluble vascular cell adhesion molecule-1 and monocyte chemoattractant protein-1 concentrations. Duration of use correlated positively with psychomotor speed. Use > 10 times/lifetime was linked to more somatic symptoms, better executive function, and lower CD14⁺CD16⁺⁺ monocyte count.

CONCLUSION

HIV+ individuals demonstrated opposing associations with cannabis. Recent use may weaken RSFC and prolonged consumption may exacerbate atrophy of the accumbens and other brain regions. More frequent or recent cannabis use may reduce the inflammation and CD14⁺CD16⁺⁺ monocytes that facilitate HIV neuroinvasion. HIV-specific cannabis studies are necessary.

Mitochondrial oxidative phosphorylation in peripheral blood mononuclear cells is decreased in chronic HIV and correlates with immune dysregulation

Background

Cellular immunometabolism among people living with HIV (PLWH) on antiretroviral therapy (ART) remains under investigated. We assessed the relationships between mitochondrial oxidative phosphorylation (OXPHOS) in peripheral blood mononuclear cells (PBMCs) and blood parameters associated with HIV immune dysregulation.

Methods

PLWH ≥40 years old and on stable ART ≥3 months were enrolled (N = 149). OXPHOS complex I (CI, NADH dehydrogenase) and complex IV (CIV, cytochrome c oxidase) protein levels in PBMCs were quantified using immunoassays. Monocyte subsets and markers of T-cell activation, senescence, and exhaustion were measured on PBMC by flow cytometry. Plasma inflammatory mediators were quantified using a multiplex assay. HIV-uninfected group (N = 44) of similar age, gender, and ethnicity had available OXPHOS levels.

Results

PLWH had a median age of 51 years. Majority were male (88.6%), Caucasian (57.7%), and with undetectable plasma HIV RNA <50 copies/mL (84.6%). Median CI level was lower in PLWH compared with the HIV-seronegative group (65.5 vs 155.0 optical density/μg protein x 10³, p <0.0001). There was no significant difference in median CIV levels. Lower OXPHOS levels correlated with lower CD4% and CD4/CD8 ratio. On multivariable linear regression adjusted for age, current use of zidovudine/didanosine, and HIV RNA (detectable versus undetectable), lower OXPHOS levels were significantly associated with higher MPO, SAA, SAP, and sVCAM, and higher frequencies of intermediate (CD14⁺⁺CD16⁺) monocytes and TIGIT+TIM3+ CD4 T-cell (p<0.01).

Conclusion

CI PBMC protein levels were decreased in PLWH on ART. Decreased OXPHOS correlated with disease severity and inflammation. Further studies on the relationship between immunometabolism and immune dysregulation in HIV are warranted.

Lower Interferon Regulatory Factor-8 Expression in Peripheral Myeloid Cells Tracks With Adverse Central Nervous System Outcomes in Treated HIV Infection

Cognitive dysfunction persists in 30–50% of chronically HIV-infected individuals despite combination antiretroviral therapy (ART). Although monocytes are implicated in poor cognitive performance, distinct biological mechanisms associated with cognitive dysfunction in HIV infection are unclear. We previously showed that a regulatory region of the interferon regulatory factor-8 (IRF8) gene is hyper-methylated in HIV-infected individuals with cognitive impairment compared to those with normal cognition. Here, we investigated IRF-8 protein expression and assessed relationships with multiple parameters associated with brain health. Intracellular IRF-8 expression was measured in cryopreserved peripheral blood mononuclear cells from chronically HIV-infected individuals on ART using flow cytometry. Neuropsychological performance was assessed by generating domain-specific standardized (NPZ) scores, with a global score defined by aggregating individual domain scores. Regional brain volumes were obtained by magnetic resonance imaging and soluble inflammatory factors were assessed by immunosorbent assays. Non-parametric analyses were conducted and statistical significance was defined as p < 0.05. Twenty aviremic (HIV RNA<50 copies/ml) participants, 84% male, median age 51 [interquartile range (IQR) 46, 55], median CD4 count 548 [439, 700] were evaluated. IRF-8 expression was highest in plasmacytoid dendritic cells (pDCs). Assessing cognitive function, lower IRF-8 density in classical monocytes significantly correlated with worse NPZ_learning memory (LM; rho = 0.556) and NPZ_working memory (WM; rho = 0.612) scores, in intermediate monocytes with worse NPZ_LM (rho = 0.532) scores, and in non-classical monocytes, lower IRF-8 correlated with worse global NPZ (rho = 0.646), NPZ_LM (rho = 0.536), NPZ_WM (rho = 0.647), and NPZ_executive function (rho = 0.605) scores. In myeloid DCs (mDCs) lower IRF-8 correlated with worse NPZ_WM (rho = 0.48) scores and in pDCs with worse NPZ_WM (rho = 0.561) scores. Declines in IRF-8 in classical monocytes significantly correlated with smaller hippocampal volume (rho = 0.573) and in intermediate and non-classical monocytes with smaller cerebral white matter volume (rho = 0.509 and rho = 0.473, respectively). IRF-8 density in DCs did not significantly correlate with brain volumes. Among biomarkers tested, higher soluble ICAM-1 levels significantly correlated with higher IRF-8 in all monocyte and DC subsets. These data may implicate IRF-8 as a novel transcription factor in the neuropathophysiology of brain abnormalities in treated HIV and serve as a potential therapeutic target to decrease the burden of cognitive dysfunction in this population.

Systemic Mitochondrial Oxidative Phosphorylation Protein Levels Correlate with Neuroimaging Measures in Chronically HIV-Infected Individuals

Few studies have examined systemic mitochondrial function in conjunction with brain imaging in human immunodeficiency virus (HIV) disease. Oxidative phosphorylation enzyme protein levels of peripheral blood mononuclear cells were measured in association with neuroimaging indices in 28 HIV+ individuals. T1-weighted magnetic resonance imaging yielded volumes of seven brain regions of interest; diffusion tensor imaging determined fractional anisotropy (FA) and mean diffusivity (MD) in the corpus callosum (CC). Higher nicotinamide adenine dinucleotide dehydrogenase levels correlated with lower volumes of thalamus (p = .005) and cerebral white matter (p = .049) and, in the CC, with lower FA (p = .011, body; p = .005, genu; p = .009, total CC) and higher MD (p = .023, body; p = .035, genu; p = .019, splenium; p = .014, total CC). Greater cytochrome c oxidase levels correlated with lower thalamic (p = .034) and cerebellar gray matter (p = .021) volumes. The results indicate that systemic mitochondrial cellular bioenergetics are associated with brain health in HIV.

Normalization of Soluble CD163 Levels After Institution of Antiretroviral Therapy During Acute HIV Infection Tracks with Fewer Neurological Abnormalities

Background

Myeloid activation contributes to cognitive impairment in chronic human immunodeficiency virus (HIV) infection. We explored whether combination antiretroviral therapy (cART) initiation during acute HIV infection impacts CD163 shedding, a myeloid activation marker, and in turn, implications on the central nervous system (CNS).

Methods

We measured soluble CD163 (sCD163) levels in plasma and cerebrospinal fluid (CSF) by enzyme-linked immunosorbent assay in Thais who initiated cART during acute HIV infection (Fiebig stages I-IV). Examination of CNS involvement included neuropsychological testing and analysis of brain metabolites by magnetic resonance spectroscopy. Chronic HIV-infected or uninfected Thais served as controls.

Results

We examined 51 adults with acute HIV infection (Fiebig stages I-III; male sex, >90%; age, 31 years). sCD163 levels before and after cART in Fiebig stage I/II were comparable to those in uninfected controls (plasma levels, 97.9 and 93.6 ng/mL, respectively, vs 99.5 ng/mL; CSF levels, 6.7 and 6.4 ng/mL, respectively, vs 7.1 ng/mL). In Fiebig stage III, sCD163 levels were elevated before cART as compared to those in uninfected controls (plasma levels, 135 ng/mL; CSF levels, 10 ng/mL; P < .01 for both comparisons) before normalization after cART (plasma levels, 90.1 ng/mL; CSF levels, 6.5 ng/mL). Before cART, higher sCD163 levels during Fiebig stage III correlated with poor CNS measures (eg, decreased N-acetylaspartate levels), but paradoxically, during Fiebig stage I/II, this association was linked with favorable CNS outcomes (eg, higher neuropsychological test scores). After cART initiation, higher sCD163 levels during Fiebig stage III were associated with negative CNS indices (eg, worse neuropsychological test scores).

Conclusion

Initiation of cART early during acute HIV infection (ie, during Fiebig stage I/II) may decrease inflammation, preventing shedding of CD163, which in turn might lower the risk of brain injury.

Elevated cerebrospinal fluid Galectin-9 is associated with central nervous system immune activation and poor cognitive performance in older HIV-infected individuals

We previously reported that galectin-9 (Gal-9), a soluble lectin with immunomodulatory properties, is elevated in plasma during HIV infection and induces HIV transcription. The link between Gal-9 and compromised neuronal function is becoming increasingly evident; however, the association with neuroHIV remains unknown. We measured Gal-9 levels by ELISA in cerebrospinal fluid (CSF) and plasma of 70 HIV-infected (HIV+) adults stratified by age (older > 40 years and younger < 40 years) either ART suppressed or with detectable CSF HIV RNA, including a subgroup with cognitive assessments, and 18 HIV uninfected (HIV-) controls. Gal-9 tissue expression was compared in necropsy brain specimens from HIV- and HIV+ donors using gene datasets and immunohistochemistry. Among older HIV+ adults, CSF Gal-9 was elevated in the ART suppressed and CSF viremic groups compared to controls, whereas in the younger group, Gal-9 levels were elevated only in the CSF viremic group (p < 0.05). CSF Gal-9 positively correlated with age in all groups (p < 0.05). CSF Gal-9 tracked with CSF HIV RNA irrespective of age (β = 0.33; p < 0.05). Higher CSF Gal-9 in the older viremic HIV+ group correlated with worse neuropsychological test performance scores independently of age and CSF HIV RNA (p < 0.05). Furthermore, CSF Gal-9 directly correlated with myeloid activation (CSF-soluble CD163 and neopterin) in both HIV+ older groups (p < 0.05). Among HIV+ necropsy specimens, Gal-9 expression was increased in select brain regions compared to controls (p < 0.05). Gal-9 may serve as a novel neuroimmuno-modulatory protein that is involved in driving cognitive deficits in those aging with HIV and may be valuable in tracking cognitive abnormalities.

Sleep and neuropsychological performance in HIV+ subjects on efavirenz-based therapy and response to switch in therapy

The antiretroviral drug efavirenz (EFV) has been linked to disordered sleep and cognitive abnormalities. We examined sleep and cognitive function and subsequent changes following switch to an alternative integrase inhibitor-based regimen. Thirty-two HIV-infected individuals on EFV, emtricitabine, and tenofovir (EFV/FTC/TDF) without traditional risk factors for obstructive sleep apnea (OSA) were randomized 2:1 to switch to elvitegravir/cobicistat/emtricitabine/tenofovir (EVG/COBI/FTC/TDF) or to continue EFV/FTC/TDF therapy for 12 weeks. Overnight polysomnography and standardized sleep and neuropsychological assessments were performed at baseline and at 12 weeks. No significant differences in change over 12 weeks were noted between the two arms in any sleep or neuropsychological test parameter. At entry, however, the rate of sleep disordered breathing (SDB) was substantially higher in study subjects compared to published age-matched norms and resulted in a high assessed OSA rate of 59.4%. Respiratory Disturbance Index (RDI), a measure of SDB, correlated with age- and education-adjusted global neuropsychological Z-score (NPZ) (r = -0.35, p = 0.05). Sleep Maintenance Efficiency, Wake after Sleep Onset, REM Sleep and RDI correlated with domain-specific NPZ for learning and memory (all p-values ≤ 0.05). Among HIV-infected individuals on EFV-based therapy and without traditional risk factors for OSA, sleep and neuropsychological abnormalities do not readily reverse after discontinuation of EFV. High baseline rates of SDB and abnormalities in sleep architecture exist in this population correlating with neuropsychological impairment. The role of HIV immuno-virologic or lifestyle factors as contributing etiologies should be explored. OSA may be an under-recognized etiology for cognitive dysfunction during chronic HIV.

Red blood cell distribution width as an easily measurable biomarker of persistent inflammation and T cell dysregulation in antiretrovirally treated HIV-infected adults

BACKGROUND

Chronic inflammation and immune dysfunction occur in human immunodeficiency virus (HIV)-infection despite stable antiretroviral therapy (ART). Red blood cell distribution width (RDW) has been shown to correlate with markers of inflammation in non-HIV conditions. The study objective was to determine associations between RDW with cellular markers of immune activation and immune dysfunction including soluble inflammatory mediators in ART treated HIV infection.

METHODS

We performed a cross-sectional analysis of the Hawaii Aging with HIV-Cardiovascular study. RDW was defined as one standard deviation of RBC size divided by mean corpuscular volume multiplied by 100%. Correlations were analyzed between RDW, soluble inflammatory biomarkers and T cell activation (CD38 + HLA-DR+), senescence (CD28-CD57+), and immune exhaustion (PD-1, TIGIT, TIM-3 expression).

RESULTS

Of 158 participants analyzed, median age was 50 years, duration of ART 12.6 years, virally suppressed 84.4%, and CD4 count 503 cells/mm3. Significant positive correlations were identified between RDW and soluble biomarkers including sICAM, IL-8, IL-6, SAA, TNF-α, sE-selection, fibrinogen, D-dimer, CRP, CD4/CD8 ratio, and frequency of multiple CD8 T-cell populations such as CD38 + HLA-DR + T-cells, single TIGIT+, and dual expressing of TIGIT + PD1+, TIGIT + TIM3+, and TIM3 + PD1+ CD8+ T-cell subsets (p < .05). Frequencies of CD38 + HLA-DR + CD8+ T-cells and TIGIT + CD8+ T-cells remained significant adjusting for baseline variables (p < .01).

CONCLUSION

Our study revealed correlations between RDW with systemic inflammatory biomarkers and CD8+ T-cell populations related to immune activation and exhaustion in HIV-infected individuals on ART. Further studies are warranted to determine the utility of RDW as a marker of immune dysregulation in HIV.

Reduced functional connectivity between ventromedial prefrontal cortex and insula relates to longer corrected QT interval in HIV+ and HIV- individuals

OBJECTIVE

Prolongation of the QT interval, i.e., measure of the time between the start of the Q wave and the end of the T wave, is a precursor to fatal cardiac arrhythmias commonly observed in individuals infected with the Human Immunodeficiency Virus (HIV), and is related to dysregulation of the autonomic nervous system. We investigated the relationship between QT interval length and resting state functional connectivity (rsFC) of the ventromedial prefrontal cortex (VMPFC), a core region of the brain that is involved with cardio-autonomic regulation.

METHOD

Eighteen HIV+ men on antiretroviral therapy and with no history of heart disease were compared with 26 HIV-negative control subjects who had similar demographic and cardio-metabolic characteristics. A seed-based rsFC analysis of the right and left VMPFC was performed at the individual subject level, and 2nd-level analyses were conducted to identify the following: group differences in connectivity, brain regions correlating with corrected (QTc) interval length before and after controlling for those group differences, and regions where seed-based rsFC correlates with CD4 count and QTc interval within HIV+ individuals.

RESULTS

HIV-negative adults showed greater rsFC between the VMPFC seed regions and several default mode network structures. Across groups greater rsFC with the left anterior insula was associated with shorter QTc intervals, whereas right posterior insula connectivity with the VMPFC correlated with greater QTc intervals. HIV patients with lower CD4 counts and higher QTc intervals showed greater rsFC between the right VMPFC and the right posterior insula and dorsal cingulate gyrus.

CONCLUSIONS

This study demonstrates that QTc interval lengths are associated with distinct patterns of VMPFC rsFC with posterior and anterior insula. In HIV patients, longer QTc interval and lower CD4 count corresponded to weaker VMPFC connectivity with the dorsal striatrum.

SIGNIFICANCE

A forebrain control mechanism may be implicated in the suppression of cardiovagal influence that confers risk for ventricular arrhythmias and sudden cardiac death in HIV+ individuals.

High 25-hydroxyvitamin D is associated with unexpectedly high plasma inflammatory markers in HIV patients on antiretroviral therapy

Inflammation associated with low 25-hydroxyvitamin D (25(OH)D) is associated with increased morbidity and mortality among HIV-infected patients with vitamin D deficiency. We investigated the association between 25(OH)D and soluble biomarkers among HIV-infected patients on stable antiretroviral therapy. This is a cross-sectional study. This study focuses on assessment in subjects 40 years or older on stable antiretroviral therapy (ART) for >3 months. Chemiluminescent immunoassay was used to determine plasma 25(OH)D levels. Plasma soluble biomarkers were measured by Luminex technology. Multivariable linear regression analysis was used to assess the associations between log10-25(OH)D and soluble biomarkers.Of 138 patients, median age was 50.5 (45, 57) years and 25(OH)D was 34.0 (25.0, 42.3) ng/mL. The majority were males (88%) and had undetectable HIV RNA (84.8%); 19 (13.8%) had 25(OH)D ≥50 ng/mL. Spline regression analyses suggested a J-shaped relationship between various plasma biomarkers and 25(OH)D. Among subjects with 25(OH)D ≥20 ng/mL, multivariable linear regression showed positive association between 25(OH)D and interleukin (IL)-10 (β = 1.84, P < 0.001), IL-6 (β = 0.72, P = 0.02), MPO (β = 0.47, P = 0.02), serum amyloid A (β = 1.20, P = 0.04), and tumor necrosis factor (TNF)-α (β = 0.51, P = 0.04). High 25(OH)D (≥50 ng/mL) was associated with higher IL-6 (β = 0.30, P = 0.009), IL-8 (β = 0.14, = 0.005), IL-10 (β = 0.43, P = 0.02), and TNF-α (β = 0.20, P = 0.04), independent of age, sex, ethnicity, body mass index, hepatitis C co-infection, current smoking status, CD4%, and HIV RNA.In older HIV-infected patients, high 25(OH)D was associated with higher (not lower) levels of proinflammatory cytokines. Higher-than-optimal 25(OH)D may be associated with immune dysregulation and may pose a potential health risk among HIV-infected patients.

Frailty Characteristics in Chronic HIV Patients are Markers of White Matter Atrophy Independently of Age and Depressive Symptoms: A Pilot Study

Background

Chronic HIV disease is associated with neurocognitive impairment and age-related conditions such as frailty.

Objective

To determine whether regional brain volumetric changes correlate with frailty parameters in older (≥ 40 years) HIV+ patients on stable combination antiretroviral therapy.

Method

Thirty-five HIV-infected participants in the Hawaii Aging with HIV Cohort - Cardiovascular Disease study underwent T1-weighted brain magnetic resonance imaging, frailty assessment and neuropsychological testing. Five physical frailty traits were assessed: low physical activity; exhaustion; unintentional weight loss; weak hand grip strength; slow walking speed. Linear regression quantified cross-sectional relationships of 12 brain regions to walking times and hand grip strength.

Results

Participants were 50.6 ± 6.8 years old and 77% had undetectable plasma viral load. One subject was frail (possessing ≥ 3 frailty traits); 23% were pre-frail (1–2 frailty traits) and had worse composite learning and memory z-scores than did non-frail individuals (p=0.06). Pre-frail or frail subjects had reduced hand grip strength relative to the non-frail group (p=0.001). Longer walking times (slower gait) related independently to lower volumes of cerebellar white matter (p<0.001, β=−0.6) and subcortical gray matter (p<0.05, β=−0.30). Reduced thalamus volume was linked to weaker grip strength (p < 0.05, β=0.4). Caudate volume was negatively associated with grip strength (p<0.01, β=−0.5).

Conclusion

Volumetric changes in cerebellar white matter and subcortical gray matter, brain regions involved in motor control and cognition, may be connected to frailty development in well-controlled HIV. Gait speed is particularly sensitive to white matter alterations and should be investigated as a predictor of frailty and brain atrophy in chronically infected patients.

Serum amyloid P (SAP) is associated with impaired brachial artery flow-mediated dilation in chronically HIV-1 infected adults on stable antiretroviral therapy

OBJECTIVE

This study aimed to evaluate the relationship between inflammatory biomarkers and endothelial dysfunction (ED), as measured by brachial artery flow-mediated dilation (FMD).

METHODS

We conducted a cross-sectional analysis utilizing baseline data of 135 participants with HIV infection on stable antiretroviral therapy (ART) in the Hawaii Aging with HIV-Cardiovascular (HAHC-CVD) study who had available baseline inflammatory biomarkers and brachial artery FMD measurements.

RESULTS

We observed significant associations between brachial artery FMD and baseline brachial artery diameter, age, male gender, traditional cardiovascular disease (CVD) risk factors such as BMI, waist to hip ratio, hypertension, systolic blood pressure (BP), diastolic BP, and LDL cholesterol, and 10-year coronary heart disease (CHD) risk estimated by Framingham risk score (FRS). Of all biomarkers tested, higher level of C-reactive protein (CRP) (beta =  - 0.695, P = 0.030) and serum amyloid P (SAP) (beta =  - 1.318, P = 0.021) were significantly associated with lower brachial artery FMD in univariable regression analysis. After adjusting for baseline brachial artery diameter, age, and selected traditional CVD risk factors in multivariable model, SAP remained significantly associated with brachial artery FMD (beta =  - 1.094, P = 0.030), while CRP was not (beta =  - 0.391, P = 0.181).

DISCUSSION

Serum amyloid P was independently associated with impaired brachial artery FMD and may potentially relate to ED and increased CVD risk in HIV-infected patients on stable ART.

Non-classical monocytes predict progression of carotid artery bifurcation intima-media thickness in HIV-infected individuals on stable antiretroviral therapy

BACKGROUND

Inflammation may contribute to cardiovascular disease (CVD) among antiretrovirally suppressed HIV-infected individuals. We assessed relationships of monocyte, CD8 T-cell activation and plasma biomarkers to changes in carotid artery intima-media thickness (CIMT).

METHODS

Longitudinal study of HIV-infected subjects ≥40 years and on stable antiretroviral therapy (ART) ≥3 months. Peripheral blood mononuclear cells were immunophenotyped by multiparameteric flow cytometry to quantify classical (CD14(++)CD16(-)), intermediate (CD14(++)CD16(+)), non-classical (CD14(low/+)CD16(++)) and transitional (CD14(+)CD16(-)) monocyte subsets and activated (CD38(+)HLA-DR(+)) CD8(+) T-cells at baseline. Plasma biomarkers were assessed by multiplex Luminex assay. High-resolution B-mode ultrasounds of right carotid arteries were obtained. Changes in CIMT over two years at the right common carotid artery (CIMTCCA) and right bifurcation (CIMTBIF) were outcome variables.

RESULTS

We studied 50 subjects: 84% male, median age 49 (Q1, Q3; 46, 56) years, median CD4 count 461 (317, 578) cells/mm(3), and with HIV RNA ≤ 50 copies/mL in 84%. Change in CIMTBIF correlated with log values of baseline absolute count of non-classical monocytes (r = 0.37, p = 0.020), and with MCP-1 (r = 0.42, p = 0.0024) and TNF-α (r = 0.30, p = 0.036) levels. In multivariable linear regression, only non-classical monocytes and MCP-1 predicted the change in CIMTBIF, independent of Framingham Risk Score and baseline CIMTBIF. No correlation was noted between CD8 T-cell activation and CIMTBIF change. Monocyte subsets, CD8 T-cell activation, and biomarker concentrations were not correlated with changes in CIMTCCA.

CONCLUSIONS

Our findings highlight the role of non-classical monocytes and MCP-1 in the progression of CIMTBIF in HIV-infected individuals on stable ART independent of traditional cardio-metabolic risk factors.

Oxidative mitochondrial DNA damage in peripheral blood mononuclear cells is associated with reduced volumes of hippocampus and subcortical gray matter in chronically HIV-infected patients

Cross-sectional relationships were examined between regional brain volumes and mitochondrial DNA (mtDNA) 8-hydroxy-2-deoxyguanosine (8-oxo-dG) in peripheral blood mononuclear cells (PBMCs) of 47 HIV patients [mean age 51years; 81% with HIV RNA ≤50copies/mL] on combination antiretroviral therapy. The gene-specific DNA damage and repair assay measured mtDNA 8-oxo-dG break frequency. Magnetic resonance imaging was performed at 3T. Higher mtDNA 8-oxo-dG was associated with lateral ventricular enlargement and with decreased volumes of hippocampus, pallidum, and total subcortical gray matter, suggesting the involvement of systemic mitochondrial-specific oxidative stress in chronic HIV-related structural brain changes and cognitive difficulties. Clarification of the mechanism may provide potential therapeutic targets.

Non-Classical Monocytes and Monocyte Chemoattractant Protein-1 (MCP-1) Correlate with Coronary Artery Calcium Progression in Chronically HIV-1 Infected Adults on Stable Antiretroviral Therapy

BACKGROUND

Persistent inflammation and immune activation has been hypothesized to contribute to increased prevalence of subclinical atherosclerosis and cardiovascular disease (CVD) risk in patients with chronic HIV infection. In this study, we examined the correlation of peripheral monocyte subsets and soluble biomarkers of inflammation to coronary artery calcium (CAC) progression, as measured by cardiac computed tomography scan.

METHODS

We conducted a longitudinal analysis utilizing baseline data of 78 participants with HIV infection on stable antiretroviral therapy (ART) in the Hawaii Aging with HIV-Cardiovascular study who had available baseline monocyte subset analysis as well as CAC measurement at baseline and at 2-year follow up. Monocyte phenotypes were assessed from cryopreserved blood by flow cytometry and plasma was assayed for soluble biomarkers using antibody-coated beads in a high sensitivity Milliplex Luminex platform. Change in CAC over 2 years was analyzed as the primary outcome variable.

RESULTS

Of all monocyte subsets and biomarkers tested, higher non-classical monocyte percentage (ρ = 0.259, p = 0.022), interleukin (IL)-6 (ρ = 0.311, p = 0.012), and monocyte chemoattractant protein (MCP)-1 (ρ = 0.524, p = <0.001) were significantly correlated to higher 2-year CAC progression in unadjusted Spearman's correlation. Non-classical monocyte percentage (ρ = 0.247, p = 0.039), and MCP-1 (ρ = 0.487, p = <0.001), remained significantly correlated to 2-year CAC progression, while IL-6 was not (ρ = 0.209, p = 0.120) after adjustment for age, hypertension, diabetes mellitus, total/HDL cholesterol ratio, smoking history, and BMI.

CONCLUSION

The percentage of non-classical monocytes and plasma MCP-1 levels were independently associated with CAC progression and may be related to the progression of atherosclerosis and increased CVD risk associated with chronic HIV infection on stable ART.

Symptoms of Autonomic Dysfunction in Human Immunodeficiency Virus

This retrospective study evaluated the frequencies of symptoms associated with autonomic dysfunction in human immunodeficiency virus (HIV)-infected patients on stable combined antiretroviral therapy. Patients infected with HIV reported higher frequencies of dysautonomia symptoms compared with HIV-negative patients, particularly in the autonomic domains related to urinary, sleep, gastroparesis, secretomotor, pupillomotor, and male sexual dysfunction.

Characterization of lipid composition and high-density lipoprotein function in HIV-infected individuals on stable antiretroviral regimens

There is an increase in the cardiovascular disease (CVD) morbidity in individuals infected with HIV that may be due to inflammatory lipid modulation not captured by traditional lipid measures. The objective of this study was to perform advanced lipoprotein phenotyping inclusive of the high-density lipoprotein (HDL) cholesterol efflux capacity and lipoprotein particle concentration and size in a well-phenotyped group of 118 patients infected with HIV. We used simple and multivariable analyses to determine the associations between advanced lipoprotein parameters and known cardiometabolic risk factors. Participants were on stable antiretroviral therapy (ART) and had benign traditional lipid panels [median total cholesterol, low-density lipoprotein (LDL)-C, HDL-C, and triglycerides of 178 mg/dl, 108 mg/dl, 44 mg/dl, and 122.5 mg/dl, respectively]. However, advanced lipoprotein phenotyping demonstrated an elevation of LDL particle number (median of 1,233 nmol/liter) and a decrease in LDL size (median of 20.4 nm), along with a decrease in protective, large HDL particles (median of 3.15 μmol/liter) and reduced HDL cholesterol efflux capacity in comparison to controls of other studies. HDL cholesterol efflux capacity was associated with HDL levels (β=0.395, p<0.001), small LDL particle concentration (β=-0.198, p=0.031), insulin sensitivity by the Matsuda index (β=0.218, p=0.029), and the Framingham Risk Score (β=-0.184, p=0.046). We demonstrate an atherogenic lipoprotein profile by NMR spectroscopy and HDL efflux measurement in a group of HIV-infected patients on stable ART with normal lipid panels.

Monocytes expand with immune dysregulation and is associated with insulin resistance in older individuals with chronic HIV

Background

Rates of insulin resistance are increased in HIV-infected patients on stable antiretroviral therapy (ART). Such increase may partially be due to HIV-induced immune dysregulation involving monocytes (MO) and its subsets.

Materials and Methods

Cross-sectional analysis of 141 HIV-infected subjects age ≥ 40 years on stable ART. Homeostatic model assessment–insulin resistance (HOMA-IR) and rates of metabolic syndrome were calculated. Subjects were classified by fasting glucose and oral glucose tolerance test (OGTT) into clinical diabetes categories. Multi-parametric flow cytometry was used to determine MO subset percentages: [classical (CD14⁺⁺CD16⁻), intermediate (CD14⁺⁺CD16⁺), non-classical (CD14^low/+CD16⁺⁺), and a recently identified fourth (CD14^low/+CD16⁻) ‘transitional’ MO subset] and percentage of activated (CD38⁺HLA-DR⁺) CD8 T cells. Absolute levels of cells were calculated using clinical CBC and T cell subset data. Multiple plasma soluble biomarkers were assessed by Luminex technology.

Results

Median age 50 years, CD4 count (percent) 505 cells/µL (29%), and 89% male. Total MO (r = −0.23, p = 0.006) and classical and non-classical MO subsets correlated negatively with CD4 percent. No correlations were seen with CD4 count as absolute values. Log-total MO and log-classical MO predicted HOMA-IR independently of HIV immuno-virologic and diabetes risk factors (β = 0.42, p = 0.02 and β = 0.35, p = 0.02, respectively) and were increased in subjects with metabolic syndrome (p = 0.03 and p = 0.05 respectively). Total and/or subset MO levels correlated with multiple soluble plasma biomarkers including CRP, IL-6, MMP-9, MPO, SAA, SAP and tPAI-1, with tPAI-1 independently predicting HOMA-IR (β = 0.74, p<0.001).

Conclusions

MO levels increase with worsening HIV immune dysregulation as assessed by CD4 percent. CD4 percent may provide additional information about MO and metabolic risk in this population beyond absolute values. MO, and specifically classical MO, may contribute to insulin resistance and metabolic syndrome during chronic HIV infection. Multiple soluble plasma biomarkers including tPAI-1 increase with increase in MO. Levels of tPAI-1 independently predict the development of insulin resistance.

Poorer neuropsychological performance increases risk for social services among HIV-infected individuals

HIV-Associated Neurocognitive Disorder (HAND) is a prevalent condition among persons with HIV resulting in cognitive impairments that may impact daily functioning. The relationship between neuropsychological (NP) test performance and functional status was investigated based on social services received (SSR) among 285 HIV-infected and 242 HIV-negative participants enrolled in the Hawai'i Aging with HIV Cohort. HIV-infected participants scored significantly lower than the HIV-negative group on all measures of NP testing and also reported receiving SSR at a higher rate. Among HIV-infected participants, more SSR correlated with poorer overall global NP performance (ρ = -0.25, P < .001), as well as poorer performance in NP domains assessing psychomotor speed (ρ = -0.25, P < .001), and learning and memory (ρ = -0.19, P = .02). NP test performance did not correlate with the number of SSR among HIV-negative participants. Supplemental Security Income (SSI) was the most commonly utilized social service among HIV-infected. Receiving SSI was associated on multivariate analysis with poorer NP performance independent of lack of full time work, or nadir CD4 count. Poorer NP performance among HIV-infected individuals is associated with increased risk for social services. Interventions to address causes of cognitive dysfunction in this population may decrease demand for social services.

Feasibility and potential role of ferumoxytol-enhanced neuroimaging in HIV-associated neurocognitive disorder

We assessed ferumoxytol-enhanced brain MRI to identify monocyte/macrophage accumulation in HIV-associated neurocognitive disorder (HAND). Four HIV-infected subjects with undetectable HIV RNA levels on antiretroviral therapy, HIV DNA level in CD14+ cells ≥10 copies/10(6) cells, and cognitive impairment underwent ferumoxytol-enhanced brain MRI. On post-ferumoxytol susceptibility-weighted images, all HIV-infected subjects demonstrated a diffuse "tram track" appearance in the perivascular regions of cortical and deep white matter vessels suggesting ferumoxytol uptake in monocytes/macrophages. This finding was not present in an HIV-seronegative control. While ferumoxytol may have potential as an imaging biomarker for monocyte/macrophage accumulation in patients with HAND, future study is needed.

Albuminuria as a marker of cardiovascular risk in HIV-infected individuals receiving stable antiretroviral therapy

Albuminuria (urinary excretion of more than 30 milligram of albumin per gram of creatinine) serves as an indicator of microvascular injury, which has been associated with atherosclerosis and cardiovascular disease in HIV-seronegative individuals. Albuminuria has been reported to be prevalent among HIV-seropositive individuals, however, the relationship between albuminuria and risk for cardiovascular disease in this population has not been well-studied. We examined the relationships between albuminuria and parameters of atherosclerosis including carotid intima-media thickness and traditional cardiovascular risk assessment among HIV-seropositive individuals receiving stable antiretroviral therapy. We utilized a cross-sectional baseline data from the Hawai'i Aging with HIV-Cardiovascular Study cohort.

RESULTS

Data was available on 111 HIV-infected patients (median age of 52 (Q1,Q3: 46, 57), male 86%; diabetes 6%; hypertension 33%; dyslipidemia 50%; median CD4 count of 489 cells/mm(3) (341, 638); HIV RNA PCR < 48 copies/ml of 85%). Eighteen subjects (16.2%) had microalbuminuria, and two subjects (1.8%) had macroalbuminuria. Albuminuria was significantly associated with increased Framingham Risk Score (P=.002), insulin resistance by HOMA-IR (P=.02), diastolic blood pressure (P=.01), and carotid intima-media thickness (P =.04). The correlation between the amount of albuminuria and carotid intima-media thickness remained significant even after adjusting for age, gender, ethnicity, current smoking status, diabetes mellitus, diastolic blood pressure, fasting insulin level, CD4 count, and HIV-RNA viral load.

CONCLUSION

Albuminuria is prevalent among HIV-infected patients receiving stable antiretroviral therapy. It is significantly related to previously defined markers of cardiovascular disease and metabolic syndrome among HIV-infected patients receiving stable antiretroviral therapy.

Predictors of 25-hydroxyvitamin D levels in HIV-infected patients in Hawai'i

HIV-infected individuals are at increased risk for several metabolic diseases, including low 25-hydroxyvitamin D [25(OH)D]. Data on the prevalence and risk factors for low 25(OH)D in HIV patients living in the tropics is scarce. Patients ≥ 40 years old on stable antiretroviral therapy were enrolled from March 2009 to July 2011 in Hawai'i (latitude 21° North). Chemiluminescent immunoassay (DiaSorin) was used to determine plasma 25(OH)D levels. Patients were grouped by whether 25(OH)D was collected in summer (May 1 - September 30) or winter (October 1 - April 30). Of 158 patients enrolled, 88 (56%) and 70 (44%) were enrolled in winter and summer, respectively. There were 57.6% Caucasians and 88% men. Over-all median (quartile1, quartile3) age was 51 (46, 57) years and median 25(OH)D was 32.4 (24.0, 41.0) ng/ml. Forty-three percent (n=68) had 25(OH)D<30.0 ng/ml. Median 25(OH)D levels were 29.6 (22.0, 38.0) ng/ml in winter and 36.9 (25.0, 44.5) ng/ml in summer (P = .01). Median body mass index (BMI) of winter patients was significantly higher (P = .03). By simple linear regression, log-transformed 25(OH)D was significantly associated with winter visit (β = -.0737, P = .01), ethnicity (Caucasian versus non-Caucasian, β = .1194, P < .01), BMI (β = -.0111, P < .01) and current use of zidovudine (β = -.1233, P = .03). In multiple linear regression, only Caucasian ethnicity (β = .1004, P < .01) and BMI (β = -.0078, P = .02) retained statistical significance. Seasonal variation in 25(OH)D was observed but the significance of winter visit was not preserved in the final multivariate model. Ethnicity and BMI were better predictors of 25(OH)D levels than season in the tropics.

Peripheral blood HIV DNA is associated with atrophy of cerebellar and subcortical gray matter

OBJECTIVE

We evaluated regional brain volumes and cerebral metabolite levels as correlates of HIV DNA in peripheral blood mononuclear cells (PBMCs).

METHODS

In this cross-sectional study, 35 HIV+ subjects aged ≥40 years (25 with detectable PBMC HIV DNA; 10 with HIV DNA <10 copies/10(6) cells, the threshold of detection) and 12 seronegative controls underwent structural brain MRI and magnetic resonance spectroscopy at 3 T. HIV+ subjects were on combination antiretroviral therapy ≥1 year; all but 1 had plasma HIV RNA <50 copies/mL. We used logistic regression to evaluate relationships of likely predictor variables to the outcome of PBMC HIV DNA detectability in the HIV+ subjects. Effects of serostatus and HIV DNA on regional brain volumes (normalized to intracranial volume) and on metabolite ratios over creatine were evaluated by analyses of covariance, controlling for age.

RESULTS

Relative to the HIV+ group with undetectable HIV DNA, subjects with detectable HIV DNA demonstrated decreased volumes of cerebellar (-14%, p = 0.020) and total subcortical (-10%, p = 0.024) gray matter. Compared to healthy controls, only the detectable HIV DNA group showed significant (p < 0.05) enlargement of lateral ventricles and volumetric reductions of caudate, putamen, thalamus, hippocampus, nucleus accumbens, brainstem, total cortical gray matter, and cerebral white matter. Detectable HIV DNA was not associated with significantly altered cerebral metabolite levels.

CONCLUSION

Inability to clear peripheral blood of HIV DNA is associated with regional brain atrophy in well-controlled HIV infection, supporting the involvement of peripheral viral reservoirs in the neuropathogenesis of persistent HIV-related neurocognitive disorders.

The effects of extended release niacin on lipoprotein sub-particle concentrations in HIV-infected patients

With the advent of highly active antiretroviral therapy (HAART), Cardiovascular Disease (CVD) has emerged as the leading cause of death in Human Immunodeficiency Virus (HIV) infected patients. An atherogenic lipoprotein phenotype has been described in HIV- infected patients with a predominance of small, low density lipoprotein (SLDL) particles with accompanying elevated triglycerides and reduced high density lipoprotein cholesterol. This randomized controlled pilot study was conducted to evaluate the efficacy of Extended Release Niacin (ERN) in improving the lipid profile in HIV patients. A total of 17 HIV positive subjects on HAART therapy with High Density Lipoprotein Cholesterol (HDL) levels below 40mg/dl and Low Density Lipoprotein Cholesterol (LDL) below 130mg/dl were enrolled. Nine were randomized to be treated with ERN titrated from a starting level of 500mg/night and titrated to a level of 1500mg/night. Eight patients were assigned to the control arm. No placebo was used. Lipoprotein profiles of the subjects were analyzed at baseline and at the end of 12 weeks using Nuclear Magnetic Resonance (NMR) spectroscopy. At the end of 12 weeks, NMR spectroscopic analysis revealed a significant increase in overall LDL size (1.2% in ERN treated subjects vs 2.0% decrease in control patients, P=.04) and a decrease in small LDL particle concentration (17.0% in ERN treated subjects vs 21.4% increase in control patients, P=.03) in subjects receiving ERN as compared to those in the control group. Only 1 subject receiving ERN developed serious flushing which was attributed to an accidental overdose of the drug. This pilot study demonstrates that ERN therapy in HIV-infected patients with low HDL is safe and effective in improving the lipoprotein profile in these patients.

Regional cortical thinning associated with detectable levels of HIV DNA

High levels of human immunodeficiency virus (HIV) DNA in peripheral blood mononuclear cells (PBMCs), and specifically within CD14+ blood monocytes, have been found in HIV-infected individuals with neurocognitive impairment and dementia. The failure of highly active antiretroviral therapy (HAART) to eliminate cognitive dysfunction in HIV may be secondary to persistence of HIV-infected PBMCs which cross the blood-brain barrier, leading to perivascular inflammation and neuronal injury. This study assessed brain cortical thickness relative to HIV DNA levels and identified, we believe for the first time, a neuroimaging correlate of detectable PBMC HIV DNA in subjects with undetectable HIV RNA. Cortical thickness was compared between age- and education-matched groups of older (>40 years) HIV-seropositive subjects on HAART who had detectable (N = 9) and undetectable (N = 10) PBMC HIV DNA. Statistical testing revealed highly significant (P < 0.001) cortical thinning associated with detectable HIV DNA. The largest regions affected were in bilateral insula, orbitofrontal and temporal cortices, right superior frontal cortex, and right caudal anterior cingulate. Cortical thinning correlated significantly with a measure of psychomotor speed. The areas of reduced cortical thickness are key nodes in cognitive and emotional processing networks and may be etiologically important in HIV-related neurological deficits.

The Impact of Depressive Symptoms on Neuropsychological Performance Tests in HIV-Infected Individuals: A Study of the Hawaii Aging with HIV Cohort

BACKGROUND: The frequency of neurocognitive impairment (NCI) in human immunodeficiency virus (HIV)-infected individuals remains high despite the availability of potent antiretroviral therapy (ART). The concurrence of depression among HIV-infected patients with NCI is common, especially among older individuals. Depression has been implicated as a risk factor for impaired neuropsychological performance (NP). This study explored the relationship between depressive symptoms and NP testing in HIV-infected individuals. METHODS: A cross-sectional analysis was performed within the Hawaii Aging with HIV Cohort, a large prospective study of cognition of older (50 or more years old) compared to younger (20 to 39 years old) HIV-infected individuals. RESULTS: Two hundred and eighty-five HIV infected participants (157 older and 128 younger) were administered a battery of NP tests to measure performance in major cognitive domains. Depressive symptoms were measured using the Beck Depression Inventory (BDI). The rates of depressive symptoms and neuropsychological impairment were similar in older and younger groups. Multivariate analyses revealed depressive symptoms were associated with NP test impairment in the younger group. In the older group, depressive symptoms were not associated with NP. CONCLUSION: This study suggests that depressive symptoms are associated with NP test impairment in younger HIV-infected individuals, but not in older individuals.