Arterial inflammation in patients with HIV

Chemoradiotherapy-related carotid artery inflammation in head and neck cancer patients quantified by [18F]FDG PET/CT

OBJECTIVES

Radiotherapy (RT) is associated with an increased risk of cardiovascular disease (CVD), but little is known about the mechanism for vascular injury and methods for early detection.

MATERIALS AND METHODS

We conducted a prospective, pilot study of carotid artery inflammation using ¹⁸F-labeled 2-fluoro-2-deoxy-d-glucose ([¹⁸F]FDG) PET/CT imaging pre- and 3 months post-RT in head-and-neck cancer (HNC) patients. [¹⁸F]FDG uptake by the carotid arteries was measured by the maximum and mean target to background ratio (TBR_MAX, TBR_MEAN) and the mean partial volume corrected standardized uptake value (pvcSUV_MEAN).

RESULTS

Of the 22 patients who completed both pre and post-RT scans, the majority (82%) had stage III or stage IV disease and received concurrent chemotherapy. TBR_MAX, TBR_MEAN, and pvcSUV_MEAN were all significantly higher 3 months after RT versus before RT with mean difference values (95% CI; p-value) of 0.17 (0.1-0.25; 0.0001), 0.19 (0.12-0.25; 0.0001), and 0.31 g/ml (0.12-0.5; 0.002), respectively. Fifteen patients (68%) had HPV-positive tumors, which were associated with lower pre-RT [¹⁸F]FDG signal, but a greater increase in TBR_MAX (19% vs 5%), TBR_MEAN (21% vs 11%) and pvcSUV_MEAN (20% increase vs 3% decrease), compared to HPV negativity.

CONCLUSION

There is a significant increase in carotid artery inflammation in HNC patients due to CRT that amounts to a degree that has previously been associated with higher risk for future CVD events. The subset of patients with HPV-positive tumors experienced the greatest increases in vascular inflammation due to CRT. Carotid [¹⁸F]FDG uptake may be an early biomarker of RT-related vascular injury.

Associations between lipids and subclinical coronary atherosclerosis

OBJECTIVE

Whether HIV modifies the relationship of serum lipids with coronary atherosclerosis and coronary plaque subtypes is uncertain. We examined the associations between traditional lipids and coronary atherosclerosis among HIV-infected (HIV+) and HIV-uninfected (HIV-) men.

DESIGN

The Multicenter AIDS Cohort Study is an observational cohort with a total of 429 HIV+ and 303 HIV- men who had non-contrast cardiac computed tomography performed to measure coronary artery calcium and coronary computed tomography angiography to measure coronary stenosis, coronary plaque presence, and composition.

METHODS

We used multivariable adjusted prevalence ratios to examine the relationship between the SD difference in each lipid parameter and coronary atherosclerosis.

RESULTS

Total cholesterol (TC)/HDL-cholesterol had the strongest associations with coronary atherosclerosis regardless of HIV status. Overall, lipid parameters were most strongly associated with the presence of mixed plaque, stenosis more than 50%, and coronary artery calcium for both HIV+ and HIV- men. HIV+ men had similar, but weaker associations, between lipid parameters and coronary atherosclerosis compared with HIV- men. The strongest association was between the TC/HDL-cholesterol and stenosis more than 50% for both HIV+ [prevalence ratios 1.25 per SD (95% confidence interval 1.07-1.43)] and HIV- men [prevalence ratios 1.46 per SD (95% confidence interval 1.08-1.85)].

CONCLUSION

The associations between lipids and coronary atherosclerosis tended to be weaker for HIV+ compared with HIV- men, although TC/HDL had the strongest association for both HIV+ and HIV- men. A weaker association between lipid levels and coronary atherosclerosis for HIV+ men may contribute to the decreased discrimination of cardiovascular disease risk observed in HIV+ individuals.

Targeting the HIV-infected brain to improve ischemic stroke outcome

HIV-associated cerebrovascular events remain highly prevalent even in the current era of antiretroviral therapy (ART). We hypothesize that low-level HIV replication and associated inflammation endure despite antiretroviral treatment and affect ischemic stroke severity and outcomes. Using the EcoHIV infection model and the middle cerebral artery occlusion as the ischemic stroke model in mice, we present in vivo analysis of the relationship between HIV and stroke outcome. EcoHIV infection increases infarct size and negatively impacts tissue and functional recovery. Ischemic stroke also results in an increase in EcoHIV presence in the affected regions, suggesting post-stroke reactivation that magnifies pro-inflammatory status. Importantly, ART with a high CNS penetration effectiveness (CPE) is more beneficial than low CPE treatment in limiting tissue injury and accelerating post-stroke recovery. These results provide potential insight for treatment of HIV-infected patients that are at risk of developing cerebrovascular disease, such as ischemic stroke.

Altered Lipidome Composition Is Related to Markers of Monocyte and Immune Activation in Antiretroviral Therapy Treated Human Immunodeficiency Virus (HIV) Infection and in Uninfected Persons

Background: HIV infection and antiretroviral therapy (ART) have both been linked to dyslipidemia and increased cardiovascular disease (CVD) risk. Alterations in the composition of saturated (SaFA), monounsaturated (MUFA), and polyunsaturated (PUFA) fatty acids are related to inflammation and CVD progression in HIV-uninfected (HIV-) populations. The relationships among the lipidome and markers of monocyte and immune activation in HIV-infected (HIV+) individuals are not well understood. Methods: Concentrations of serum lipids and their fatty acid composition were measured by direct infusion-tandem mass spectrometry in samples from 20 ART-treated HIV+ individuals and 20 HIV- individuals. Results: HIV+ individuals had increased levels of free fatty acids (FFAs) with enrichment of SaFAs, including palmitic acid (16:0) and stearic acid (18:0), and these levels were directly associated with markers of monocyte (CD40, HLA-DR, TLR4, CD36) and serum inflammation (LBP, CRP). PUFA levels were reduced significantly in HIV+ individuals, and many individual PUFA species levels were inversely related to markers of monocyte activation, such as tissue factor, TLR4, CD69, and SR-A. Also in HIV+ individuals, the composition of lysophosphatidylcholine (LPC) was enriched for SaFAs; LPC species containing SaFAs were directly associated with IL-6 levels and monocyte activation. We similarly observed direct relationships between levels of SaFAs and inflammation in HIV uninfected individuals. Further, SaFA exposure altered monocyte subset phenotypes and inflammatory cytokine production in vitro. Conclusions: The lipidome is altered in ART-treated HIV infection, and may contribute to inflammation and CVD progression. Detailed lipidomic analyses may better assess CVD risk in both HIV+ and HIV- individuals than does traditional lipid profiling.

Severe infection increases cardiovascular risk among HIV-infected individuals

BACKGROUND

The identification and management of cardiovascular risk factors became a major clinical issue among HIV-infected individuals in the post-cART era. As in the past decades the link between acute infections and cardiovascular diseases became clear in the general population, we sorted to investigate the role of severe infections on incident cardiovascular diseases (CVDs) among HIV-infected individuals.

METHODS

HIV-infected individuals aged ≥18 years, with no history of CVD were followed from January 2000 to December 2013 until the occurrence of the first CVD event, death or end of study, whichever occurred first. To explore the effect of severe infections on the incidence of CVD we used extended Cox regression models and stratified post-hospitalization follow-up time into three periods: < 3 months, 3-12 months and > 12 months post discharge.

RESULTS

One hundred-eighty four persons from 3384 HIV-infected individuals developed incident CVD events during the follow-up (incidence rate = 11.10/1000 PY (95%CI: 9.60-12.82)). Risk of an incident CVD was 4-fold higher at < 3 months post-hospitalization for severe infections (adjusted hazard ratio [aHR], 4.52; 95% confidence interval [CI] 2.46-8.30), after adjusting for sociodemographic and clinical factors as well as comorbidities. This risk remained significant up to one year (3-12 months post hospital discharge aHR 2.39, 95% CI 1.30-4.38). Additionally, non-white race/ethnicity (aHR 1.49, 95% CI 1.10-2.02), age ≥ 60 years (aHR 2.01, 95% CI 1.01-3.97) and hypertension (aHR 1.90, 95% CI 1.38-2.60) were associated with an increased risk of CVD events. High CD4 (≥ 500 cells/mm3: aHR 0.41, 95% CI 0.27-0.62) and cART use (aHR 0.21, 95% CI 0.14-0.31) reduced the risk of CVD events.

CONCLUSIONS

We provide evidence for a time-dependent association between severe infection and incident cardiovascular disease in HIV-infected individuals. cART use, and high CD4 count were significantly associated with reduced hazards of CVD.

Radionuclide imaging of inflammation in atherosclerotic vascular disease among people living with HIV infection: current practice and future perspective

People living with human immunodeficiency virus (HIV) infection have twice the risk of atherosclerotic vascular disease compared with non-infected individuals. Inflammation plays a critical role in the development and progression of atherosclerotic vascular disease. Therapies targeting inflammation irrespective of serum lipid levels have been shown to be effective in preventing the occurrence of CVD. Radionuclide imaging is a viable method for evaluating arterial inflammation. This evaluation is useful in quantifying CVD risk and for assessing the effectiveness of anti-inflammatory treatment. The most tested radionuclide method for quantifying arterial inflammation among people living with HIV infection has been with F-18 FDG PET/CT. The level of arterial uptake of F-18 FDG correlates with vascular inflammation and with the risk of development and progression of atherosclerotic disease. Several limitations exist to the use of F-18 FDG for PET quantification of arterial inflammation. Many targets expressed on macrophage, a significant player in arterial inflammation, have the potential for use in evaluating arterial inflammation among people living with HIV infection. The review describes the clinical utility of F-18 FDG PET/CT in assessing arterial inflammation as a risk for atherosclerotic disease among people living with HIV infection. It also outlines potential newer probes that may quantify arterial inflammation in the HIV-infected population by targeting different proteins expressed on macrophages.

Inflammatory biomarkers and subclinical carotid atherosclerosis in HIV-infected and HIV-uninfected men in the Multicenter AIDS Cohort Study

BACKGROUND

HIV-infected persons have an increased risk of atherosclerosis relative to uninfected individuals. Inflammatory processes may contribute to this risk. We evaluated the associations of 10 biomarkers of systemic inflammation (CRP, IL-6, sTNF-αR1 and 2), monocyte activation (CCL2, sCD163, sCD14), coagulation (fibrinogen, D-dimer), and endothelial dysfunction (ICAM-1) with subclinical carotid atherosclerosis among participants in the Multicenter AIDS Cohort Study (MACS).

METHODS

Carotid plaque and intima media thickness (IMT) in the common carotid (CCA-IMT) and bifurcation region were assessed by B mode ultrasound among 452 HIV-infected and 276 HIV-uninfected men from 2010-2013. Associations between levels of each biomarker and presence of focal plaque and IMT were assessed by logistic and linear regression models, adjusting for demographics, risk behaviors, traditional cardiovascular disease (CVD) risk factors, and HIV disease characteristics.

RESULTS

Compared to HIV-uninfected men, HIV-infected men had significantly higher levels of 8 of the 10 biomarkers. Overall, men with sCD163, CCL2, IL-6, and CRP levels in the highest quintile had approximately 2 times the odds of carotid plaque relative to those with levels in the lowest quintile, independent of demographic and CVD risk factors. Fibrinogen levels were positively associated with CCA-IMT while ICAM-1, CCL2, and sTNF-αR1 levels were positively associated with bifurcation-IMT. Among HIV-uninfected men, higher levels of sTNF-αR2 were positively associated with CCA-IMT, fibrinogen with bifurcation-IMT and carotid plaque, and ICAM-1 with carotid plaque.

CONCLUSION

In addition to greater levels of systemic inflammation, heightened monocyte activation (sCD163, CCL2) may contribute to the burden of atherosclerosis among HIV-infected persons.

Effects of HIV-1 gp120 and tat on endothelial cell sensescence and senescence-associated microRNAs

The aim of this study was to determine, in vitro, the effects of X4 and R5 HIV‐1 gp120 and Tat on: (1) endothelial cell senescence and (2) endothelial cell microRNA (miR) expression. Endothelial cells were treated with media without and with: R5 gp120 (100 ng/mL), X4 gp120 (100 ng/mL), or Tat (500 ng/mL) for 24 h and stained for senescence‐associated β‐galactosidase (SA‐β‐gal). Cell expression of miR‐34a, miR‐217, and miR‐146a was determined by RT‐PCR. X4 and R5 gp120 and Tat significantly increased (~100%) cellular senescence versus control. X4 gp120 significantly increased cell expression of miR‐34a (1.60 ± 0.04 fold) and miR‐217 (1.52 ± 0.18), but not miR‐146a (1.25 ± 0.32). R5 gp120 significantly increased miR‐34a (1.23 ± 0.07) and decreased miR‐146a (0.56 ± 0.07). Tat significantly increased miR‐34a (1.49 ± 0.16) and decreased miR‐146a (0.55 ± 0.23). R5 and Tat had no effect on miR‐217 (1.05 ± 0.13 and 1.06 ± 0.24; respectively). HIV‐1 gp120 (X4 and R5) and Tat promote endothelial cell senescence and dysregulation of senescence‐associated miRs.

Relationship of visceral and subcutaneous adipose depots to markers of arterial injury and inflammation among individuals with HIV

OBJECTIVE

Persons living with HIV (PLWH) well treated on antiretroviral therapies remain at risk for ensuing arterial disease. We investigated the relationship between adipose depots and biomarkers of arterial injury and inflammation to gain insight into the link between body composition and CVD risk.

DESIGNS/METHODS

One hundred and fifty-five HIV-infected and 70 non-HIV infected individuals were well phenotyped for body composition. Adipose depots were assessed via single-slice abdominal computed tomography (CT). Circulating markers of arterial disease and generalized inflammation [lipoprotein-associated phospholipase A2 (LpPLA2), oxidized low-density lipoprotein (oxLDL), high-sensitivity cardiac troponin T (hs-cTnT), high-sensitivity C-reactive protein (hsCRP)] were evaluated.

RESULTS

Despite similar BMI and visceral adipose tissue (VAT), HIV-infected individuals had significantly lower subcutaneous adipose tissue [SAT, 199 (126-288) vs. 239 (148-358) cm(2), P = 0.04] than non-HIV infected individuals. Among HIV-infected individuals, reduced SAT inversely correlated with LpPLA2 (ρ = -0.19, P = 0.02) and hs-cTnT (ρ = -0.24, P = 0.004), whereas increased VAT significantly and positively related to LpPLA2 (ρ = 0.25, P = 0.003), oxLDL (ρ = 0.28, P = 0.0005), hs-cTnT (ρ = 0.28, P = 0.0007) and hsCRP (ρ = 0.32, P =  < 0.0001). Similar analyses among the non-HIV infected individuals revealed significant relationships between SAT and LpPLA2 (ρ = -0.24, P = 0.05), as well as VAT and LpPLA2 (ρ = 0.37, P = 0.002), oxLDL (ρ = 0.24, P = 0.05) and hsCRP (ρ = 0.29, P = .02). In modelling performed among the HIV group, simultaneously controlling for VAT, SAT, age and relevant HIV-related parameters, reduced SAT was an independent predictor of LpPLA2 (P = 0.04) and hs-cTnT (P = 0.005) and increased VAT was an independent predictor of LpPLA2 (P = 0.001), oxLDL (P = 0.02), hs-cTnT (P = 0.04) and hsCRP (P = 0.04).

CONCLUSION

Fat redistribution phenotypes, characterized by SAT loss and/or VAT accumulation, may be linked to arterial injury and inflammation in HIV.

Atrial fibrillation and human immunodeficiency virus type-1 infection: a systematic review. Implications for anticoagulant and antiarrhythmic therapy

The prevalence and incidence of atrial fibrillation/flutter (AF/AFL) in patients with human immunodeficiency virus type-1 (HIV-1) infection have been poorly investigated. We performed a systematic review using PubMed and Cochrane Database of Systematic Reviews, and screening of references, searching for clinical studies reporting on the association between HIV-1 infection and AF/AFL. We also summarized the main interactions of antiretroviral agents with antithrombotic and antiarrhythmic drugs. We found a prevalence of AF/AFL ranging from 2.0% to 5.13% in patients with HIV-1, with an incidence rate of 3.6/1000 person-years. Low CD4+ count (<200-250 cells ml^-1 ) and high viral load were predictors of AF/AFL. Regarding drugs interactions, nucleoside reverse transcriptase inhibitors, integrase inhibitor and maraviroc have the lowest interactions with oral anticoagulants. Among anticoagulants, dabigatran presents the most favourable profile. Most of antiarrhythmic drugs interact with protease inhibitors, with beta blockers and diltiazem having fewer interactions. The few studies available suggest a non-negligible prevalence of AF/AFL in patients with HIV-1 infection. Awareness of potential interactions with anticoagulation and antiarrhythmic drugs is needed to offer optimal management in this population.

The Role of Macrophages in HIV-1 Persistence and Pathogenesis

Current antiretroviral therapy (ART) effectively suppresses Human Immunodeficiency Virus type 1 (HIV-1) in infected individuals. However, even long term ART does not eradicate HIV-1 infected cells and the virus persists in cellular reservoirs. Beside memory CD4⁺ T cells, cells of the myeloid lineage, especially macrophages, are believed to be an important sanctuary for HIV-1. Monocytes and macrophages are key players in the innate immune response to pathogens and are recruited to sites of infection and inflammation. Due to their long life span and ability to reside in virtually every tissue, macrophages have been proposed to play a critical role in the establishment and persistence of the HIV-1 reservoir. Current HIV-1 cure strategies mainly focus on the concept of "shock and kill" to purge the viral reservoir. This approach aims to reactivate viral protein production in latently infected cells, which subsequently are eliminated as a consequence of viral replication, or recognized and killed by the immune system. Macrophage susceptibility to HIV-1 infection is dependent on the local microenvironment, suggesting that molecular pathways directing differentiation and polarization are involved. Current latency reversing agents (LRA) are mainly designed to reactivate the HIV-1 provirus in CD4+ T cells, while their ability to abolish viral latency in macrophages is largely unknown. Moreover, the resistance of macrophages to HIV-1 mediated kill and the presence of infected macrophages in immune privileged regions including the central nervous system (CNS), may pose a barrier to elimination of infected cells by current "shock and kill" strategies. This review focusses on the role of monocytes/macrophages in HIV-1 persistence. We will discuss mechanisms of viral latency and persistence in monocytes/macrophages. Furthermore, the role of these cells in HIV-1 tissue distribution and pathogenesis will be discussed.

Mechanisms of Cardiovascular Disease in the Setting of HIV Infection

Although the initial reports of increased cardiovascular (CV) disease in the setting of advanced AIDS were reported approximately 30 years ago, advances in antiretroviral therapy and immediate initiation of therapy on diagnosis have transformed what was once a deadly infectious disease into a chronic health condition. Accordingly, the types of CV diseases occurring in HIV have shifted from pericardial effusions and dilated cardiomyopathy to atherosclerosis and heart failure. The underlying pathophysiology of HIV-associated CV disease remains poorly understood, partly because of the rapidly evolving nature of HIV treatment and because clinical endpoints take many years to develop. The gut plays an important role in the early pathogenesis of HIV infection as HIV preferentially infects CD4+ T cells, 80% of which are located in gut mucosa. The loss of these T cells damages gut mucosa resulting in increased gut permeability and microbial translocation, which incites chronic inflammation and immune activation. Antiretroviral therapy does not cure HIV infection and immune abnormalities persist. These abnormalities correlate with mortality and CV events. The effects of antiretroviral therapy on CV risk are complex; treatment reduces inflammation and other markers of CV risk but induces lipid abnormalities, most commonly hypertriglyceridemia. On a molecular level, monocytes/macrophages, platelet reactivity, and immune cell activation, which play a role in the general population, may be heightened in the setting of HIV and contribute to HIV-associated atherosclerosis. Chronic inflammation represents an inviting therapeutic target in HIV, as it does in uninfected persons with atherosclerosis.

Burden of subclinical carotid atherosclerosis and vascular risk factors among people living with HIV in Ghana

BACKGROUND

The burden of cardiovascular disease (CVD) among people living with HIV (PLWH) in sub-Saharan Africa is projected to rise due to a rapid epidemiological transition and improved treatment of HIV infection on the sub-continent.

OBJECTIVE

The Evaluation of Vascular Event Risk while on Long-term Anti-retroviral Suppressive Therapy (EVERLAST) Study sought to assess the extent of subclinical atherosclerosis and characterize the nature of CVD risk factors among HIV patients on Antiretroviral therapy (ART) in Ghana.

METHODS

We conducted a cross-sectional study involving HIV patients on antiretroviral therapy (n = 250) in comparison with HIV positive ART naïve (n = 201), and HIV uninfected controls (n = 250). We assessed prevalence of hypertension, dyslipidemia, diabetes mellitus, central obesity, and carotid atherosclerosis using B-mode carotid Doppler ultrasonography. We assessed factors associated with subclinical atherosclerosis defined by a carotid intimal media thickness (CIMT) cut-off of ≥0.78 mm among PLWH using a logistic regression model.

RESULTS

Mean age of PLWH on combination ART (cART) was 45.7 ± 8.6 years, 42.9 ± 8.8 years among PLWH not on cART, and 44.9 ± 9.5 years among HIV negative controls of which 81.2%, 81.6% and 81.1% respectively were females. Prevalence of subclinical atherosclerosis at the common carotid artery in the three groups was 67.6%, 66.7% and 62.4%, p = 0.43. Among PLWH, raised serum total cholesterol (OR 1.16, 95% CI: 1.00-1.35) and triglycerides (OR 1.32, 95% CI: 1.01-1.73) were significantly associated with subclinical atherosclerosis. Prevalence of vascular risk factors among PLWH on cART, PLWH cART naïve, and HIV negative controls respectively were as follows: dyslipidemia- 79.5%, 83.1%, and 73.5%, p = 0.04; hypertension- 40.2%, 23.4%, and 44.9%, p < 0.0001; central obesity-61.8%, 66.7%, and 78.2%, p < 0.0001; diabetes mellitus-6.8%, 5.5% and 4.9%, p = 0.53.

CONCLUSION

Overall while there is a high baseline prevalence of CVD risk factors in the Ghanaian population, serum lipid derangements appear to be more prevalent among HIV infected patients, and are linked to sub-clinical atherosclerosis. Future studies need to confirm these findings, explore the underlying pathophysiology, and optimize treatment strategies to avert untoward CVD outcomes.

Noninvasive Cardiovascular Imaging: Emergence of a Powerful Tool for Early Identification of Cardiovascular Risk in People Living With HIV

Antiretroviral therapy (ART) has been pivotal in prolonging the lifespan of people living with HIV (PLWH). However, this also simultaneously increases their risk of cardiovascular disease (CVD) either related to ART, aging, hypertension, immunosenescence, inflammation, immune activation, or other comorbidities. Although the use of risk markers has greatly enhanced the field of cardiovascular (CV) medicine and improved the prognosis and early diagnosis in the general population, this strategy has not been clearly elucidated in PLWH. Developing accurate risk algorithms for PLWH requires an innate understanding of mechanistic factors influencing their risks. Early identification of CV risk will significantly enhance the prospects of PLWH living longer and relatively healthily. Herein, we discuss the use of multimodality noninvasive CV imaging as robust markers for ameliorating CV risk. The ability to prognosticate CV risk and hence prevent CV events in PLWH would represent an important advance in CV medicine, allowing precise detection and early institution of preventative strategies. Using novel CV imaging modalities and strategies would have a positive impact on precision medicine in this patient cohort.

Impact of the American College of Cardiology/American Heart Association Cholesterol Guidelines on Statin Eligibility Among Human Immunodeficiency Virus-Infected Individuals

Background

Individuals with human immunodeficiency virus (HIV) face elevated cardiovascular disease (CVD) risk. There are limited data regarding the application of the American College of Cardiology/American Heart Association (ACC/AHA) cholesterol guidelines in HIV compared with non-HIV patients.

Methods

Human immunodeficiency virus-infected and demographically similar control patients were assessed for statin recommendation status by ACC/AHA and the National Cholesterol Education Program Adult Treatment Program III (ATPIII), indication for statin recommendation, actual statin prescription, and CVD event. Outcomes were atherosclerotic CVD for ACC/AHA and coronary heart disease for ATPIII.

Results

In a clinical care cohort of 1394 patients infected with HIV, 38.6% (538 of 1394) of patients were recommended for statin therapy by the ACC/AHA guidelines compared with 20.1% (280 of 1394) by the ATPIII guidelines. Of those recommended for statin therapy, actual statin prescription rates were 42.8% (230 of 538) for ACC/AHA and 66.4% (186 of 280) for ATPIII. Among patients infected with HIV with an incident CVD event during follow-up, statin therapy was recommended for 59.2% (42 of 71) of patients by ACC/AHA and 35.2% (25 of 71) by ATPIII, versus 71.6% (141 of 197) by ACC/AHA and 43.1% (85 of 197) by ATPIII in the control group.

Conclusions

In an HIV clinical care cohort, the ACC/AHA cholesterol guidelines recommend a higher proportion of patients for statin therapy and identify an increased proportion of patients with a CVD event compared with ATPIII. However, 40% of patients with a CVD event would not have been recommended for statin therapy by ACC/AHA, compared with 29% for controls. This gap in identification of patients infected with HIV at high CVD risk underscores the need for HIV-specific cardiovascular prevention strategies.

Cardiac Surgery in HIV Patients: State of the Art

The clinical status of HIV infection has changed dramatically with the introduction of combined antiretroviral therapy. Patients with HIV are now living long enough to be susceptible to chronic illnesses, such as coronary disease and nonischemic cardiomyopathy, which can be consequences of the combined antiretroviral therapy treatment itself. Cardiovascular diseases are a major source of morbidity and mortality in HIV-positive patients. Increasingly, such patients might be candidates for the full range of cardiac surgical interventions, including coronary bypass, valve surgery, and heart transplantation. There has been a shift from offering palliative procedures such as pericardial window and balloon valvuloplasty, to more conventional and durable surgical therapies in HIV-positive patients. We herein provide an overview of the contemporary outcomes of cardiac surgery in this complex and unique patient population. We review some of the ethical issues around the selection and surgical care of HIV-positive patients. We also discuss strategies to best protect the surgical treatment team from the risks of HIV transmission. Finally, we highlight the need for involvement of dedicated infectious disease professionals in a multidisciplinary heart team approach, aiming at the comprehensive care of these unique and complex patients.

Lipid Abnormalities in Persons Living With HIV Infection

Lipid abnormalities are prevalent among persons living with HIV infection and contribute to increasing the risk of cardiovascular events. Antiretroviral therapy (ART) is associated with lipid abnormalities, most commonly hypertriglyceridemia, but also increases in low-density lipoprotein cholesterol and total cholesterol. Different classes of ART, and different drugs within classes, have differing effects on lipid levels, but in general newer drugs have more favourable effects compared with older ones. Low-level inflammation and chronic immune activation act on lipids through a variety of mechanisms to make them more atherogenic. As a consequence, risk is higher than would be expected for any given cholesterol level. Clinical outcome trials of cholesterol-lowering therapies have not yet been completed in people living with HIV, so that treatment decisions depend on extrapolation from studies in uninfected populations. Traditional risk assessment tools underestimate cardiovascular risk in individuals with HIV. Statins are the mainstay of lipid-lowering drug treatment; however, drug-drug interactions with ART must be considered. Simvastatin and lovastatin are contraindicated in patients taking protease inhibitors, and the dose of atorvastatin and rosuvastatin should be limited to 40 mg and 10 mg/d with some ART combinations. Switching from older forms of ART to lipid-friendly newer ones is a useful strategy as long as virologic suppression is maintained, but adding a statin lowers low-density lipoprotein cholesterol more effectively. Studies indicate that lipid abnormalities are not treated as aggressively in individuals living with HIV as they are in uninfected people, making this an opportunity to improve care.

Effects of Antiretroviral Therapy on Immune Function and Arterial Inflammation in Treatment-Naive Patients With Human Immunodeficiency Virus Infection

IMPORTANCE

Individuals with human immunodeficiency virus (HIV) infection receiving combined antiretroviral therapy (ART) have an increased risk of myocardial infarction. Effects of ART on arterial inflammation among treatment-naive individuals with HIV are unknown.

OBJECTIVE

To determine the effects of newly initiated ART on arterial inflammation and other immune/inflammatory indices in ART-naive patients with HIV infection.

DESIGN, SETTING, PARTICIPANTS

Twelve treatment-naive HIV-infected individuals underwent fludeoxyglucose F 18 ([18F]-FDG) positron emission tomographic scanning for assessment of arterial inflammation, coronary computed tomographic angiography for assessment of subclinical atherosclerosis, and systemic immune and metabolic phenotyping before and 6 months after the initiation of therapy with elvitegravir, cobicistat, emtricitabine, and tenofovir disoproxil fumarate (combined ART). Systemic immune and metabolic factors were also assessed in 12 prospectively recruited individuals without HIV serving as controls. The study began July 24, 2012, and was completed May 7, 2015.

INTERVENTIONS

Combined ART in the HIV-infected cohort.

MAIN OUTCOMES AND MEASURES

The primary outcome was change in aortic target-background ratio (TBR) on [18F]-FDG-PET with combined ART in the HIV-infected group.

RESULTS

For the 12 participants with HIV infection (mean (SD) age, 35 [11] years), combined ART suppressed viral load (mean [SD] log viral load, from 4.3 [0.6] to 1.3 [0] copies/mL; P < .001), increased the CD4+ T-cell count (median [IQR], from 461 [332-663] to 687 [533-882] cells/mm3; P < .001), and markedly reduced percentages of circulating activated CD4+ T cells (human leukocyte antigen-D related [HLA-DR]+CD38+CD4+) (from 3.7 [1.8-5.0] to 1.3 [0.3-2.0]; P = .008) and CD8+ T cells (HLA-DR+CD38+CD8+) (from 18.3 [8.1-27.0] to 4.0 [1.5-7.8]; P = .008), increased the percentage of circulating classical CD14+CD16- monocytes (from 85.8 [83.7-90.8] to 91.8 [87.5-93.2]; P = .04), and reduced levels of CXCL10 (mean [SD] log CXCL10, from 2.4 [0.4] to 2.2 [0.4] pg/mL; P = .03). With combined ART, uptake of [18F]-FDG in the axillary lymph nodes, as measured by TBR, decreased from a median (IQR) of 3.7 (1.3-7.0) at baseline to 1.4 (0.9-1.9; P = .01) at study end. In contrast, no significant decrease was seen in aortic TBR in response to combined ART (mean [SD], 1.9 [0.2]; median [IQR], 2.0 [1.8-2.1] at baseline to 2.2 [0.4]; 2.1 [1.9-2.6], respectively, at study end; P = .04 by 2-way test, P = .98 for test of decrease by 1-way test). Changes in aortic TBR during combined ART were significantly associated with changes in lipoprotein-associated phospholipase A2 (n = 10; r = 0.67; P = .03). Coronary plaque increased among 3 participants with HIV infection with baseline plaque and developed de novo in 1 participant during combined ART.

CONCLUSIONS AND RELEVANCE

Newly initiated combined ART in treatment-naive individuals with HIV infection had discordant effects to restore immune function without reducing arterial inflammation. Complementary strategies to reduce arterial inflammation among ART-treated HIV-infected individuals may be needed.

Monocyte and haematopoietic progenitor reprogramming as common mechanism underlying chronic inflammatory and cardiovascular diseases

A large number of cardiovascular events are not prevented by current therapeutic regimens. In search for additional, innovative strategies, immune cells have been recognized as key players contributing to atherosclerotic plaque progression and destabilization. Particularly the role of innate immune cells is of major interest, following the recent paradigm shift that innate immunity, long considered to be incapable of learning, does exhibit immunological memory mediated via epigenetic reprogramming. Compelling evidence shows that atherosclerotic risk factors promote immune cell migration by pre-activation of circulating innate immune cells. Innate immune cell activation via metabolic and epigenetic reprogramming perpetuates a systemic low-grade inflammatory state in cardiovascular disease (CVD) that is also common in other chronic inflammatory disorders. This opens a new therapeutic area in which metabolic or epigenetic modulation of innate immune cells may result in decreased systemic chronic inflammation, alleviating CVD, and its co-morbidities.

Examining Relationships between Metabolism and Persistent Inflammation in HIV Patients on Antiretroviral Therapy

With the advent of antiretroviral therapy (ART), HIV-infected individuals are now living longer and healthier lives. However, ART does not completely restore health and treated individuals are experiencing increased rates of noncommunicable diseases such as dyslipidemia, insulin resistance, type 2 diabetes, cardiovascular disease, and nonalcoholic fatty liver disease. While it is well known that persistent immune activation and inflammation contribute to the development of these comorbid diseases, the mechanisms underlying this chronic activation remain incompletely understood. In this review, we will discuss emerging evidence that suggests that alterations in cellular metabolism may play a central role in driving this immune dysfunction in HIV patients on ART.

Global Burden of Atherosclerotic Cardiovascular Disease in People Living With HIV: Systematic Review and Meta-Analysis

BACKGROUND

With advances in antiretroviral therapy, most deaths in people with HIV are now attributable to noncommunicable illnesses, especially cardiovascular disease. We determine the association between HIV and cardiovascular disease, and estimate the national, regional, and global burden of cardiovascular disease attributable to HIV.

METHODS

We conducted a systematic review across 5 databases from inception to August 2016 for longitudinal studies of cardiovascular disease in HIV infection. A random-effects meta-analysis across 80 studies was used to derive the pooled rate and risk of cardiovascular disease in people living with HIV. We then estimated the temporal changes in the population-attributable fraction and disability-adjusted life-years (DALYs) from HIV-associated cardiovascular disease from 1990 to 2015 at a regional and global level. National cardiovascular DALYs associated with HIV for 2015 were derived for 154 of the 193 United Nations member states. The main outcome measure was the pooled estimate of the rate and risk of cardiovascular disease in people living with HIV and the national, regional, and global estimates of DALYs from cardiovascular disease associated with HIV.

RESULTS

In 793 635 people living with HIV and a total follow-up of 3.5 million person-years, the crude rate of cardiovascular disease was 61.8 (95% CI, 45.8-83.4) per 10 000 person-years. In comparison with individuals without HIV, the risk ratio for cardiovascular disease was 2.16 (95% CI, 1.68-2.77). Over the past 26 years, the global population-attributable fraction from cardiovascular disease attributable to HIV increased from 0.36% (95% CI, 0.21%-0.56%) to 0.92% (95% CI, 0.55%-1.41%), and DALYs increased from 0.74 (95% CI, 0.44-1.16) to 2.57 (95% CI, 1.53-3.92) million. There was marked regional variation with most DALYs lost in sub-Saharan Africa (0.87 million, 95% CI, 0.43-1.70) and the Asia Pacific (0.39 million, 95% CI, 0.23-0.62) regions. The highest population-attributable fraction and burden were observed in Swaziland, Botswana, and Lesotho.

CONCLUSIONS

People living with HIV are twice as likely to develop cardiovascular disease. The global burden of HIV-associated cardiovascular disease has tripled over the past 2 decades and is now responsible for 2.6 million DALYs per annum with the greatest impact in sub-Saharan Africa and the Asia Pacific regions.

CLINICAL TRIAL REGISTRATION

URL: https://www.crd.york.ac.uk/prospero . Unique identifier: CRD42016048257.

Zidovudine-Based Treatments Inhibit the Glycosylation of ADAM17 and Reduce CD163 Shedding From Monocytes

BACKGROUND

sCD163, a biomarker of monocyte-macrophage activation, has been identified as a predictor of all-cause mortality in treated HIV-infected individuals. Nevertheless, little is known about whether different antiretroviral drugs differentially regulate sCD163 levels and monocyte activation.

METHODS

A total of 123 patients receiving zidovudine (ZDV)-based (n = 55) or tenofovir disoproxil fumarate (TDF)-based (n = 68) antiretroviral regimens were enrolled, and their viral loads, CD4 counts, as well as plasma sCD163 and sCD14 levels were quantified. Twenty-eight (14 in each group) patients donated additional blood samples for flow cytometry and gene expression analyses using purified monocytes. THP-1 cultures were also used to investigate the effect of ZDV on ADAM17, which is responsible for CD163 shedding.

RESULTS

As compared to the TDF-treated group, the ZDV-treated group had lower plasma sCD163 levels and higher CD163 expression on CD14++CD16 monocytes. Five metabolic-inflammatory genes exhibited significantly different expression levels between purified monocytes of the ZDV and TDF groups (IL-6, 2.90-fold lower in ZDV group, P < 0.001; iNOS, 1.81-fold higher; CX3CR1, 1.72-fold lower; MIP-1β, 1.10-fold lower; and PPARγ-1, 1.36-fold higher, P < 0.05). Moreover, we show that ZDV treatment increases the surface expression of CD163 in cultured THP-1 cells, accompanied by the inhibition of glycosylation and surface expression of ADAM17.

CONCLUSIONS

Compared with TDF treatment, ZDV treatment causes lower plasma sCD163 levels, probably by inhibiting the glycosylation of ADAM17 and CD163 shedding. Our results show that ZDV functions as an ADAM17 inhibitor in vivo and extend our understanding of its immune-modulatory effects and adverse effects.

Assessing statin effects on cardiovascular pathways in HIV using a novel proteomics approach: Analysis of data from INTREPID, a randomized controlled trial

Background

People with HIV (PWH) demonstrate increased cardiovascular disease (CVD), due in part to increased immune activation, inflammation, and endothelial dysfunction.

Methods

In a randomized trial (INTREPID), 252 HIV-infected participants with dyslipidemia and no history of coronary artery disease were randomized (1:1) to pitavastatin 4 mg vs. pravastatin 40 mg for 52 weeks. Using a proteomic discovery approach, 92 proteins biomarkers were assessed using Proximity Extension Assay technology to determine the effects of statins on key atherosclerosis and CVD pathways among PWH. 225 participants had specimens available for biomarker analysis pre- and post-baseline.

Findings

The mean age was 49.5 ± 8.0 (mean ± SD), LDL-C 155 ± 25 mg/dl and CD4 count 620 ± 243 cell/mm³. Among all participants, three proteins significantly decreased: tissue factor pathway inhibitor [TFPI; t-statistic = −6.38, FDR p-value<0.0001], paraoxonase 3 [PON3; t-statistic = −4.64, FDR p-value = 0.0003], and LDL-receptor [LDLR; t-statistic = −4.45, FDR p-value = 0.0004]; and two proteins significantly increased galectin-4 [Gal-4; t-statistic = 3.50, FDR p-value = 0.01] and insulin-like growth factor binding protein 2 [IGFBP-2; t-statistic = 3.21, FDR p-value = 0.03]. The change in TFPI was significantly different between the pitavastatin and pravastatin groups. Among all participants, change in TFPI related to the change in LDL-C (r = 0.43, P < 0.0001) and change in Lp-PLA2 (r = 0.29, P < 0.0001).

Interpretation

Using a proteomics approach, we demonstrated that statins led to a significant reduction in the levels of TFPI, PON3, and LDLR and an increase in Gal-4 and IGFBP-2, key proteins involved in coagulation, redox signaling, oxidative stress, and glucose metabolism. Pitavastatin led to a greater reduction in TFPI than pravastatin. These data highlight potential novel mechanisms of statin effects among PWH.

Fund

This work was supported by an investigator-initiated grant to S.K.G. from KOWA Pharmaceuticals America, Inc. and the National Institutes of Health [P30 DK040561; Nutrition Obesity Research Center at Harvard]. M.T. was support by National Institutes of Health [5KL2TR001100-05; Harvard Catalyst KL2 grant].

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Among PWH, statins significantly decreased three proteins [tissue factor pathway inhibitor (TFPI), paraoxonase 3 (PON3), and LDL-receptor (LDLR)].

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Among PWH, statins significantly increased galectin-4 (Gal-4) and insulin-like growth factor binding protein 2 (IGFBP-2).

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The proteins significantly affected by statin therapy are involved in important pathways in atherosclerosis and cardiovascular disease.

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The change in TFPI was directly related to the change in LDL-C and a systemic marker of arterial inflammation (Lp-PLA2).

Cenicriviroc inhibits trans-endothelial passage of monocytes and is associated with impaired E-selectin expression

Incidences of cardiovascular diseases (CVD) are high among virologically suppressed HIV-infected individuals. Monocyte activation and trafficking are key mechanisms in the evolution of CVD. We studied the ability of cenicriviroc (CVC), a dual C-C chemokine receptor type 2 (CCR2) and CCR5 antagonist, to influence the migration of monocytes from HIV-infected individuals on antiretroviral therapy (ART). Monocytes were derived from 23 ART-suppressed HIV-infected and 16 HIV-uninfected donors. In a trans-endothelial migration model, monocytes, and human aortic endothelial cells (HAoECs) were exposed to cenicriviroc and migrated monocytes, quantified. Expression of CCR2 and CCR5 on monocytes and adhesion molecules (E-selectin, ICAM-1, VCAM-1, PECAM-1, and CD99) on HAoECs were measured. The single antagonists, BMS-22 (CCR2), and maraviroc (CCR5), served as controls. When both HAoECs and monocytes together were exposed to the antagonists, cenicriviroc led to a greater decrease in monocyte migration compared to BMS-22 or vehicle in both HIV-infected and HIV-uninfected groups (P < 0.05), with maraviroc having no inhibitory effect. Cenicriviroc treatment of HAoECs alone decreased monocyte migration in the HIV-infected group when compared to vehicle (P < 0.01). Inhibition of migration was not evident when monocytes alone were exposed to cenicriviroc, BMS-22 or maraviroc. Incubation of HAoECs with cenicriviroc decreased E-selectin expression (P = 0.045) but had limited effects on the other adhesion molecules. Cenicriviroc inhibits monocyte trans-endothelial migration more effectively than single chemokine receptor blockade, which may be mediated via disruption of monocyte-endothelial tethering through reduced E-selectin expression. Cenicriviroc should be considered as a therapeutic intervention to reduce detrimental monocyte trafficking.

Differences by HIV serostatus in coronary artery disease severity and likelihood of percutaneous coronary intervention following stress testing

BACKGROUND

HIV-infected persons develop coronary artery disease (CAD) more commonly and earlier than uninfected persons; however, the role of non-invasive testing to stratify CAD risk in HIV is not well defined.

METHODS AND RESULTS

Patients were selected from a single-center electronic cohort of HIV-infected patients and uninfected controls matched 1:2 on age, sex, race, and type of cardiovascular testing performed. Patients with abnormal echocardiographic or nuclear stress testing who subsequently underwent coronary angiography were included. Logistic regressions were used to assess differences by HIV serostatus in two co-primary endpoints: (1) severe CAD (≥70% stenosis of at least one coronary artery) and (2) performance of percutaneous coronary intervention (PCI). HIV-infected patients (N = 189) were significantly more likely to undergo PCI following abnormal stress test when compared with uninfected persons (N = 319) after adjustment for demographics, CAD risk factors, previous coronary intervention, and stress test type (OR 1.85, 95% CI 1.12-3.04, P = 0.003). No associations between HIV serostatus and CAD were statistically significant, although there was a non-significant trend toward greater CAD for HIV-infected patients.

CONCLUSIONS

HIV-infected patients with abnormal cardiovascular stress testing who underwent subsequent coronary angiography did not have a significantly greater CAD burden than uninfected controls, but were significantly more likely to receive PCI.

Cardiovascular disease risk among women living with HIV in North America and Europe

PURPOSE OF REVIEW

To examine the epidemiology and mechanistic underpinnings of heightened cardiovascular disease (CVD) risk among women living with HIV (WLHIV) in North America and Europe.

RECENT FINDINGS

WLHIV in North America and Europe exhibit high CVD incidence rates, which are at par with those of compatriot men living with HIV. Compared with uninfected women, WLHIV in these regions face a 2-4-fold increased relative risk for myocardial infarction, stroke, and heart failure. HIV-associated CVD risk is fuelled by a negative synergy of traditional cardiometabolic risk factors and heightened systemic immune activation/inflammation. Among WLHIV, female sex and endogenous sex hormone production influence both traditional cardiometabolic risk factors and patterns of systemic immune activation/inflammation. WLHIV in North America and Europe may also experience heightened CVD risk in relation to a relatively increased prevalence of behavioral and psychosocial CVD risk factors, coupled with suboptimal therapeutic targeting of known traditional cardiometabolic risk factors.

SUMMARY

Additional research on sex-specific mechanisms of HIV-associated CVD - based not only out of North America and Europe but also and especially out of Africa, Asia, and South America - will inform the development of CVD prediction algorithms and prevention guidelines clinically relevant to the approximately 17 million women aging with HIV globally.

HIV disease is associated with increased biomarkers of endothelial dysfunction despite viral suppression on long-term antiretroviral therapy in Botswana

Background

Untreated HIV infection is associated with increased biomarkers of endothelial dysfunction. However, the predictors and degree of endothelial dysfunction among virally suppressed HIV–infected adults on long–term antiretroviral therapy (ART) have not been well studied in sub– Saharan Africa (SSA).

Methods

We enrolled 112 HIV–infected adults with virological suppression on long–term ART and 84 HIV–uninfected controls in Botswana. We measured plasma levels of markers of endothelial injury [soluble vascular adhesion molecule 1 (VCAM–1), intercellular adhesion molecule 1 (ICAM–1) and E–selectin] and plasma levels of biomarkers of inflammation [interleukin 6 (IL–6)] and monocyte activation (sCD163). Baseline traditional cardiovascular disease (CVD) risk factors and bilateral common carotid intima–media thickness (cIMT) were also available for all participants. We assessed whether HIV status (despite virological suppression on ART) was associated with biomarkers of endothelial dysfunction after controlling for traditional CVD risk factors in linear regression models. We additionally assessed the association between IL–6, sCD163 and cIMT with endothelial dysfunction in separate multivariate linear regression models, controlling for cIMT, among virally suppressed HIV–infected participants only.

Results

In multivariate analysis, HIV infection was significantly associated with increased VCAM–1 (p < 0.01) and ICAM–1 (p = 0.03) but not E–selectin (p = 0.74) levels. Within the HIV–positive group, higher sCD163 levels were associated with decreased ICAM–1 and E–selectin (p < 0.01 and p = 0.01, respectively) but not VCAM–1 (p = 0.13) levels. IL–6 was not associated with any of the biomarkers of endothelial dysfunction.

Conclusion

HIV disease was associated with biomarkers of endothelial dysfunction among virally suppressed adults in Botswana on long–term ART after controlling for traditional CVD risk factors. Future work should explore the clinical impact of persistent endothelial dysfunction following longterm HIV viral suppression on the risk of CVD clinical endpoints among HIV–infected patients in this setting.

Novel mediators of statin effects on plaque in HIV: a proteomics approach

OBJECTIVE

HIV patients have increased atherosclerotic coronary vascular disease (ASCVD), thought to be mediated through inflammatory mechanisms. We hypothesized that among asymptomatic HIV-infected patients with subclinical coronary plaque, statin therapy would modulate unique inflammatory and cardiovascular proteins in relation to change in subclinical coronary plaque volume. We tested this hypothesis using a novel proteomics approach.

DESIGN

Forty HIV-infected participants were randomized to atorvastatin (40 mg/day) versus placebo, and underwent computed tomography coronary angiography to quantify plaque volume at baseline and 1 year.

METHODS

We used Olink Cardiovascular III and Cardiometabolic panels based on dual antibody epitope recognition with linked DNA amplification to compare change over time in 184 proteins in treatment versus placebo and in relation to change in coronary plaque volume.

RESULTS

Six proteins (TFPI, CCL24, NT-Pro BNP, MBL2, LTBR, PCOLCE) changed significantly in the atorvastatin versus placebo group, many in innate immune and other novel inflammatory pathways. Twenty-six proteins changed significantly in relationship to total coronary plaque volume over 1 year. Notably, many of these proteins changed only weakly in relationship to change in low-density lipoprotein (LDL). Overlapping these two broad discovery approaches, proteins involved in myocardial fibrosis/collagen formation and monocyte chemoattraction changed with statin treatment, in relationship to plaque volume, but not LDL.

CONCLUSION

This proof-of-concept study employing a proteomic discovery platform offers insight into statin effects on novel immune pathways relevant to ASCVD progression in HIV. Novel biomarker discovery may enhance precision medicine strategies to estimate the efficacy of targeted therapies to reduce ASCVD progression and events in HIV.

Caspase-1-associated immune activation in an accelerated SIV-infected rhesus macaque model

In the antiretroviral therapy (ART) era, chronic HIV infection is primarily associated with chronic inflammation driving comorbidities such as cardiovascular disease and neurocognitive impairment. Caspase-1 activation in leukocytes has been documented in HIV infection; however, whether caspase-1 activation and the downstream pro-inflammatory cytokines interleukin-1beta (IL-1β) and interleukin-18 (IL-18) contribute to chronic inflammation in HIV comorbidities remains undetermined. The relationship between the caspase-1 cascade and persistent inflammation in HIV has not been investigated. Here, we used an accelerated simian immunodeficiency virus (SIV)-infected rhesus macaque model with or without ART to investigate the dynamics of caspase-1 and immune cell activation before infection, 21 days post infection (dpi), and necropsy. Caspase-1, IL-18, IL-1β, and immune markers were measured both in the circulation and lymphoid tissues. We found a significant increase in caspase-1 and IL-18 in SIV infection that positively correlated with inflammatory monocytes and negatively correlated with CD4⁺ T cell counts. ART attenuated these effects at necropsy in the circulation. Further, lymph nodes from SIV+ or SIV+ART animals had increased activation of caspase-1 and potential upstream priming of the NF-κB pathway, indicating that tissue-specific immune activation persists with ART. Together, these results shed light on the interconnectedness of the caspase-1 pathway and peripheral immune activation and further indicate that ART is not sufficient for suppressing inflammation. The caspase-1 pathway may provide novel therapeutic targets to improve HIV-associated comorbidities and health outcomes in the context of viral suppression.

Diastolic Dysfunction in Individuals With Human Immunodeficiency Virus Infection: Literature Review, Rationale and Design of the Characterizing Heart Function on Antiretroviral Therapy (CHART) Study

Antiretroviral therapy (ART) has been associated with a shift in the epidemiology of human immunodeficiency virus (HIV)-associated cardiomyopathy from a phenotype of primarily left ventricular (LV) systolic dysfunction to LV diastolic dysfunction (DD). Patients with HIV receiving ART have higher rates of DD compared with age-matched control subjects and develop DD at a younger age. However, little is known about the natural history and pathogenesis of DD in virally suppressed HIV-infected patients. Current evidence suggests that immune processes modulate the risk for cardiac involvement in HIV-infected persons. Ongoing inflammation appears to have myocardial effects, and accelerated myocardial fibrosis appears to be a key mediator of HIV-induced DD. The Characterizing Heart Function on Antiretroviral Therapy (CHART) study aims to systematically investigate determinants, mechanisms, and consequences of DD in HIV-infected patients. We will compare ART-treated virally suppressed HIV-infected individuals with and without DD and HIV- individuals with DD regarding (1) systemic inflammation, myocardial stress, and subclinical myocardial necrosis as indicated by circulating biomarkers; (2) immune system activation as indicated by cell surface receptors; (3) myocardial fibrosis according to cardiac magnetic resonance examination; (4) markers of fibrosis and remodeling, oxidative stress, and hypercoagulability; (5) left atrial function according to echocardiographic examination; (6) myocardial stress and subclinical necrosis as indicated by circulating biomarkers; (7) proteomic and metabolic profiles; and (8) phenotype signatures derived from clinical, biomarker, and imaging data.

Short Communication: The Effect of Rosuvastatin on Vascular Disease Differs by Smoking Status in Treated HIV Infection

Smoking is an important contributor to cardiovascular disease risk and is highly prevalent in the HIV population. In the Stopping Atherosclerosis and Treating Unhealthy Bone with Rosuvastatin in HIV trial (SATURN-HIV), a 96-week, randomized placebo-controlled study testing the effect of rosuvastatin on subclinical vascular disease and immune activation in HIV-infected adults, rosuvastatin improved immune activation and arrested common carotid artery intima media thickness (CCA IMT) progression. In this exploratory analysis, ANOVA was used to test for effect modification by smoking. One-hundred forty-seven adults were included (72 in rosuvastatin group; 75 in placebo group). Groups were similar at baseline. Overall, mean ± SD age was 45.4 ± 9.9 years, 115 (78%) were men and 100 (68%) were African American. Ninety-three (63%) were current smokers (mean ± SD 0.6 ± 0.44 packs/day) and another 24 (16%) were smokers in the past. There were statistically significant randomization group by smoking status interactions for 0-24 (p = .01) and 0-48 (p < .01) week changes in proportion of activated CD4⁺ T cells and for 0-48 (p < .01) and 0-96 (trend only; p = .06) week changes in CCA IMT. No effect modification by smoking was detected for changes in markers of inflammation or monocyte activation. The beneficial effect of rosuvastatin on CCA IMT was not apparent in smokers although T cell activation improved to a greater degree in this subgroup.

Ageing with HIV

The population of people living with HIV (PLWH) is growing older with an estimated 4 million over the age of 50 years, a figure which has doubled since the introduction of effective antiretroviral therapy (ART) and which is increasing globally. Despite effective ART, PLWH still experience excess morbidity and mortality compared to the general population with increased prevalence of age-related, non-AIDS illnesses (NAI) such as cardiovascular disease, malignancies, cognitive impairment and reduced bone mineral density, which impact disability and everyday functioning. This review will discuss the challenges presented by comorbidities in ageing PLWH and discuss the aetiology and management of age-related illnesses in this vulnerable population.

An SIV macaque model of SIV and HAND: the need for adjunctive therapies in HIV that target activated monocytes and macrophages

Non-human primate models of AIDS and neuroAIDS are critical to study HIV infection of the CNS, neuropathology, and immune activation and macrophage accumulation that occurs in HAND. SIV, similar to HIV, infects CD4⁺ T lymphocytes and monocytes/macrophages. Virus enters the CNS early, and macrophage activation correlates with CNS disease, as well as inflammation outside of the CNS. Antiretroviral in HIV+ humans and SIV+ Rhesus macaques results in non-detectable plasma virus, decreased or non-detectable viral RNA or protein in the CNS. But, viral DNA rebounds following therapy interruption, demonstrating the presence of replication competent virus in the CNS within myeloid cells. In this brief review, we discuss our findings using a Rhesus macaque model of SIV-associated CNS infection and pathology, focusing on monocyte/macrophage activation and the link between CNS and cardiac disease. We conclude with recent studies using adjunctive therapy targeting monocytes/macrophages with ART to prevent or diminish CNS pathology that may be associated with HAND.

Cardiovascular Disease and HIV: Pathophysiology, Treatment Considerations, and Nursing Implications

HIV infection has progressed from an acute, terminal disease to a chronic illness with cardiovascular disease as the leading cause of death among persons living with HIV. As persons living with HIV infection continue to become older, traditional risk factors for atherosclerosis compounded by the pathophysiological effects of HIV infection and antiretroviral therapy markedly increase the risk for cardiovascular disease. Further, persons living with HIV are also at high risk for cardiomyopathy. Critical care nurses must recognize the risk factors for cardiovascular disease and the pathophysiology and complex treatment options in order to manage care of these patients and facilitate multidisciplinary collaboration. Two case studies are used to highlight the treatment options and nursing considerations associated with cardiovascular disease among persons living with HIV.

High Prevalence of Hypertension in Ethiopian and Non-Ethiopian HIV-Infected Adults

Objectives

Prevalence of hypertension has not been studied in the Ethiopian HIV-infected population, which represents 60% of the patients in our AIDS unit. Our aim was to identify risk factors and characterize the prevalence of hypertension in the population monitored at our unit.

Methods

A retrospective chart review categorized subjects according to their blood pressure levels. Hypertension prevalence was determined and stratified according to variables perceived to contribute to elevated blood pressure.

Results

The prevalence of hypertension in our study population was significantly higher compared to the general population (53% versus 20%, P < 0.0001) and was associated with known risk factors and not with patients' viral load and CD4 levels. Ethiopian HIV-infected adults had a prominently higher rate of blood pressure rise over time as compared to non-Ethiopians (P = 0.016).

Conclusions

The high prevalence of hypertension in this cohort and the rapid increase in blood pressure in Ethiopians are alarming. We could not attribute high prevalence to HIV-related factors and we presume it is part of the metabolic syndrome. The lifelong cardiovascular risk associated with HIV infection mandates hypertension screening and close monitoring in this population.

HIV-associated changes in the enteric microbial community: potential role in loss of homeostasis and development of systemic inflammation

Supplemental Digital Content is available in the text

Purpose of review

Despite HIV therapy advances, average life expectancy in HIV-infected individuals on effective treatment is significantly decreased relative to uninfected persons, largely because of increased incidence of inflammation-related diseases, such as cardiovascular disease and renal dysfunction. The enteric microbial community could potentially cause this inflammation, as HIV-driven destruction of gastrointestinal CD4⁺ T cells may disturb the microbiota–mucosal immune system balance, disrupting the stable gut microbiome and leading to further deleterious host outcomes.

Recent findings

Varied enteric microbiome changes have been reported during HIV infection, but unifying patterns have emerged. Community diversity is decreased, similar to pathologies such as inflammatory bowel disease, obesity, and Clostridium difficile infection. Many taxa frequently enriched in HIV-infected individuals, such as Enterobacteriaceae and Erysipelotrichaceae, have pathogenic potential, whereas depleted taxa, such as Bacteroidaceae and Ruminococcaceae, are more linked with anti-inflammatory properties and maintenance of gut homeostasis. The gut viral community in HIV has been found to contain a greater abundance of pathogenesis-associated Adenoviridae and Anelloviridae. These bacterial and viral changes correlate with increased systemic inflammatory markers, such as serum sCD14, sCD163, and IL-6.

Summary

Enteric microbial community changes may contribute to chronic HIV pathogenesis, but more investigation is necessary, especially in the developing world population with the greatest HIV burden (Video, Supplemental Digital Content 1, which includes the authors’ summary of the importance of the work).

The effects of HIV and smoking on aortic and splenic inflammation

OBJECTIVE

To determine the association of smoking and HIV status with tissue-specific inflammation measured by flurodeoxyglucose positron emission tomography (PET).

DESIGN

A cross-sectional study.

METHODS

We prospectively enrolled 55 HIV study participants on stable antiretroviral therapy and 19 age-matched HIV-uninfected controls without known cardiovascular disease. We measured aortic target-to-background ratio (TBR) and spleen standardized uptake values (SUV) 3-h post-FDG, and used regression models to examine the independent association of HIV and smoking status with PET variables.

RESULTS

Overall, median (interquartile range) age was 50 (42-55) years; 81% were men and 54% were current smokers (median 0.5 packs/day, 25 pack-years]. Median CD4 of HIV study participants was 690 cells/ml and 88% had HIV-1 RNA less than 20 c/ml; 43% were on a protease inhibitor. In fully adjusted models, HIV was associated with 0.16 (95% confidence interval 0.04-0.27; P = 0.009) higher aortic TBR, whereas current smoking was marginally associated with a lower TBR [-0.11 (95% confidence interval -0.23 to 0.01); P = 0.07]. Spleen SUVmean was not associated with HIV or smoking, and there was no evidence for an HIVsmoking interaction for aortic or spleen models (all P > 0.1). Spleen SUVmean was positively associated with biomarkers of inflammation and coronary artery calcium, but adjustment for traditional cardiovascular disease risk factors attenuated these relationships.

CONCLUSION

The FDG-PET study of HIV study participants suggests that HIV is associated with increased aortic inflammation independent of traditional risk factors, but smoking is not. Future studies should continue to explore the mechanistic roles of smoking and inflammation at various stages of clinical and subclinical atherosclerotic vascular disease in HIV.

NOVEL MECHANISMS AND ANTI-INFLAMMATORY STRATEGIES TO REDUCE CARDIOVASCULAR RISK IN HUMAN IMMUNODEFICIENCY VIRUS

Cardiovascular disease (CVD) rates are 50% to 100% higher in human immunodeficiency virus (HIV) patients. Traditional risks account for only 25% of this excess risk. Excess CVD risk in HIV may relate in part to increases in ectopic adipose depots. CVD in HIV-infection is characterized by atypical highly vulnerable plaque lesions, which are inflamed, in tight relationship to immune, and monocyte activation pathways. Using ¹⁸fluorine-2-deoxy-D-glucose positron-emission tomography imaging techniques, we have shown increased arterial inflammation which persists even after effective antiretroviral therapy. More recent studies, using a novel macrophage specific imaging agent in humans, have shown highly increased inflammatory patterns in large vessels in HIV. In addition, statins may be uniquely valuable among HIV patients, not only lowering low-density lipoprotein, but also reducing monocyte chemo-attraction, and immune activation pathways. These data have led the National Institutes of Health to fund the Randomized Trial to Prevent Vascular Events in HIV (REPRIEVE), the first large multicenter primary CVD prevention trial in HIV, aimed at assessing inflammatory mechanisms of CVD in HIV.

Patrolling Mechanics of Non-Classical Monocytes in Vascular Inflammation

Non-classical monocytes have emerged as the preeminent vascular housekeepers. Continuous intravascular screening is enabled by slow patrolling on the endothelium and allows a rapid response to local perturbations. Intravital imaging has been crucial to elucidate the molecular mechanisms and migratory phenotype of patrolling. In this review, we discuss technical requirements of intravital microscopy such as imaging modalities, labeling strategies, and data analysis. We further focus on patrolling kinetics and adhesion receptors in different organs and vascular beds including arteries during homeostasis and vascular inflammation and define pertinent questions in the field.

Atherosclerotic Cardiovascular Disease and Anti-Retroviral Therapy

In the current era of available therapy for human immunodeficiency virus (HIV), life expectancy for persons living with HIV (PLWH) nears that of the general population. Atherosclerotic cardiovascular disease (ASCVD) has become a particular burden for PLWH and society at large. PLWH have historically been shown to have an excess of cardiovascular risk and subsequent events when compared to the general population. Potential explanations include the increased prevalence of traditional risk factors, direct inflammatory and immunological effects from the HIV virus itself, and metabolic adverse effects of anti-retroviral therapy (ART). Over the past few years, there has been building evidence that chronic inflammation and immune activation independent of virologic suppression contribute significantly to excess ASCVD risk. Although independent agents and combination therapies have varying metabolic effects, the evidence from major randomized controlled trials (RCTs) supports the benefits of early initiation of ART. In this review, we will discuss the epidemiology of ASCVD in HIV-infected patients compared with the general population, give an overview of potential pathogenesis of high-risk plaque in HIV-infected patients, discuss different metabolic effects of individual anti-retrovirals, and discuss the limitations in current screening models for assessing cardiovascular disease (CVD) risk and future directions for treatment.

Monocyte subsets exhibit transcriptional plasticity and a shared response to interferon in SIV-infected rhesus macaques

The progression to AIDS is influenced by changes in the biology of heterogeneous monocyte subsets. Classical (CD14++CD16-), intermediate (CD14++CD16+), and nonclassical (CD14+CD16++) monocytes may represent progressive stages of monocyte maturation or disparate myeloid lineages with different turnover rates and function. To investigate the relationship between monocyte subsets and the response to SIV infection, we performed microarray analysis of monocyte subsets in rhesus macaques at three time points: prior to SIV infection, 26 days postinfection, and necropsy with AIDS. Genes with a 2-fold change between monocyte subsets (2023 genes) or infection time points (424 genes) were selected. We identify 172 genes differentially expressed among monocyte subsets in both uninfected and SIV-infected animals. Classical monocytes express genes associated with inflammatory responses and cell proliferation. Nonclassical monocytes express genes associated with activation, immune effector functions, and cell cycle inhibition. The classical and intermediate subsets are most similar at all time points, and transcriptional similarity between intermediate and nonclassical monocytes increases with AIDS. Cytosolic sensors of nucleic acids, restriction factors, and IFN-stimulated genes are induced in all three subsets with AIDS. We conclude that SIV infection alters the transcriptional relationship between monocyte subsets and that the innate immune response to SIV infection is conserved across monocyte subsets.

Nonprogressing HIV-infected children share fundamental immunological features of nonpathogenic SIV infection

Disease-free infection in HIV-infected adults is associated with human leukocyte antigen-mediated suppression of viremia, whereas in the sooty mangabey and other healthy natural hosts of simian immunodeficiency virus (SIV), viral replication continues unabated. To better understand factors preventing HIV disease, we investigated pediatric infection, where AIDS typically develops more rapidly than in adults. Among 170 nonprogressing antiretroviral therapy-naïve children aged >5 years maintaining normal-for-age CD4 T cell counts, immune activation levels were low despite high viremia (median, 26,000 copies/ml). Potent, broadly neutralizing antibody responses in most of the subjects and strong virus-specific T cell activity were present but did not drive pediatric nonprogression. However, reduced CCR5 expression and low HIV infection in long-lived central memory CD4 T cells were observed in pediatric nonprogressors. These children therefore express two cardinal immunological features of nonpathogenic SIV infection in sooty mangabeys-low immune activation despite high viremia and low CCR5 expression on long-lived central memory CD4 T cells-suggesting closer similarities with nonpathogenetic mechanisms evolved over thousands of years in natural SIV hosts than those operating in HIV-infected adults.

Sex Differences in Select Non-communicable HIV-Associated Comorbidities: Exploring the Role of Systemic Immune Activation/Inflammation

PURPOSE OF THE REVIEW

The goals of this review are to (1) explore HIV-associated cardiovascular disease (CVD), neurocognitive impairment, and non-AIDS-defining cancers (NADC) as heterogeneous model disease states fuelled in part by systemic immune activation/inflammation; (2) consider sex differences in the epidemiology of these diseases in both high-resource and lower-resource settings; and (3) examine biological and environmental factors which may contribute to heightened systemic immune activation/inflammation specifically among women living with HIV (WLHIV).

RECENT FINDINGS

The observation that WLHIV have higher levels of systemic immune activation/inflammation than men living with HIV (MLHIV) may be relevant to sex differences in select non-communicable HIV-associated comorbidities. Heightened systemic immune activation among WLHIV may be influenced by sex-specific responses to the virus and to immunomodulatory agents, as well as by behavioral choices/comorbid conditions and perturbations in the hypothalamic-pituitary-gonadal axis. Additional research is needed to elucidate region-specific drivers of heightened systemic immune activation/inflammation among WLHIV and to determine whether WLHIV who present with one immune-mediated HIV-associated comorbidity (e.g., cognitive impairment) may be at increased risk for another (e.g., CVD, NADC). This kind of research would facilitate improved risk prediction for non-communicable HIV-associated comorbidities among WLHIV and the development of targeted immunomodulatory prevention strategies.

Human immunodeficiency virus and liver disease: A comprehensive update

Among persons living with human immunodeficiency virus (HIV) infection, liver disease remains a major cause of morbidity and mortality. While the etiologies are varied and often overlapping in the individual patient, the underlying mechanisms, including oxidative stress, direct activation of stellate cells, HIV interaction with hepatocytes, and bacterial translocation with systemic immune activation, seem to be unifying characteristics. Early and fully suppressive HIV antiretroviral therapy is a mainstay of management either before or concurrent with treatment of etiologic cofactors, including hepatitis C virus, hepatitis B virus, and nonalcoholic fatty liver disease/nonalcoholic steatohepatitis. Significant barriers to care that still exist include liver disease recognition, appropriate linkage to care, ongoing substance abuse, and psychiatric comorbidities in the HIV-infected population. Emerging issues in these patients include acute and chronic hepatitis E, underreported hepatitis D, and a rising incidence of hepatocellular carcinoma. (Hepatology Communications 2017;1:987-1001).

Systemic Inflammation, Coagulation, and Clinical Risk in the START Trial

Background

The Strategic Timing of AntiRetroviral Treatment (START) trial demonstrated that immediate (at CD4+ >500 cells/µL) vs deferred (to CD4+ <350 cells/µL or AIDS) antiretroviral therapy (ART) initiation reduced risk for AIDS and serious non-AIDS (SNA). We investigated associations of inflammation, coagulation, and vascular injury biomarkers with AIDS, SNA or death, and the effect of immediate ART initiation.

Methods

Biomarkers were measured from stored plasma prior to randomization and at month 8. Associations of baseline biomarkers with event risk were estimated with Cox regression, pooled across groups, adjusted for age, gender, and treatment group, and stratified by region. Mean changes over 8 months were estimated and compared between the immediate and deferred ART arms using analysis of covariance models, adjusted for levels at entry.

Results

Baseline biomarker levels were available for 4299 START participants (92%). Mean follow-up was 3.2 years. Higher levels of IL-6 and D-dimer were the only biomarkers associated with risk for AIDS, SNA or death, as well as the individual components of SNA and AIDS events (HRs ranged 1.37-1.41 per 2-fold higher level), even after adjustment for baseline CD4+ count, HIV RNA level, and other biomarkers. At month 8, biomarker levels were lower in the immediate arm by 12%-21%.

Conclusions

These data, combined with evidence from prior biomarker studies, demonstrate that IL-6 and D-dimer consistently predict clinical risk across a broad spectrum of CD4 counts for those both ART-naïve and treated. Research is needed to identify disease-modifying treatments that target inflammation beyond the effects of ART.

HIV protease inhibitor-induced cardiac dysfunction and fibrosis is mediated by platelet-derived TGF-β1 and can be suppressed by exogenous carbon monoxide

Human immunodeficiency virus (HIV) infection is an independent risk factor for cardiovascular disease. This risk is magnified by certain antiretrovirals, particularly the protease inhibitor ritonavir, but the pathophysiology of this connection is unknown. We postulated that a major mechanism for antiretroviral-associated cardiac disease is pathologic fibrosis linked to platelet activation with release and activation of transforming growth factor (TGF)-β1, and that these changes could be modeled in a murine system. We also sought to intervene utilizing inhaled carbon monoxide (CO) as proof-of-concept for therapeutics capable of regulating TGF-β1 signaling and collagen autophagy. We demonstrate decreased cardiac function indices, including cardiac output, ejection fraction and stroke volume, and prominent cardiac fibrosis, in mice exposed to pharmacological doses of ritonavir. Cardiac output and fibrosis correlated with plasma TGF-β1 levels. Mice with targeted deletion of TGF-β1 in megakaryocytes/platelets (PF4CreTgfb1^flox/flox) were partially protected from ritonavir-induced cardiac dysfunction and fibrosis. Inhalation of low dose CO (250ppm), used as a surrogate for upregulation of inducible heme oxygenase/endogenous CO pathways, suppressed ritonavir-induced cardiac fibrosis. This occurred in association with modulation of canonical (Smad2) and non-canonical (p38) TGF-β1 signaling pathways. In addition, CO treatment suppressed the M1 pro-inflammatory subset of macrophages and increased M2c regulatory cells in the hearts of RTV-exposed animals. The effects of CO were dependent upon autophagy as CO did not mitigate ritonavir-induced fibrosis in autophagy-deficient LC3^-/- mice. These results suggest that platelet-derived TGF-β1 contributes to ritonavir-associated cardiac dysfunction and fibrosis, extending the relevance of our findings to other antiretrovirals that also activate platelets. The anti-fibrotic effects of CO are linked to alterations in TGF-β1 signaling and autophagy, suggesting a proof-of-concept for novel interventions in HIV/antiretroviral therapy-mediated cardiovascular disease.

Inflammation, Immune Activation, and Antiretroviral Therapy in HIV

PURPOSE OF REVIEW

This review focuses on the differential effects of contemporary antiretrovirals on systemic inflammation as heightened immune activation is linked to important co-morbidities and mortality with HIV infection.

RECENT FINDINGS

Antiretroviral therapy (ART) reduces dramatically systemic inflammation and immune activation, but not to levels synchronous with HIV-uninfected populations. In one ART initiation trial, integrase inhibitors appear to reduce inflammation to a greater degree than non-nucleoside reverse transcriptase inhibitors (NNRTIs); however, it is not clear that there are beneficial effects on inflammation resulting from treatment with integrase inhibitors compared to PIs, between PIs and NNRTIs, between specific nucleoside reverse transcriptase inhibitors, or with maraviroc in ART-naïve patients. In ART switch studies, changing to an integrase inhibitor from a PI-, NNRTI-, or enfuvirtide-containing regimen has resulted in improvement in several markers of inflammation. Additional research is needed to conclusively state whether there are clear differences in effects of specific antiretrovirals on inflammation and immune activation in HIV.