Endothelial dysfunction, increased inflammation, and activated coagulation in HIV-infected patients improve after initiation of highly active antiretroviral therapy

Comparison of Retinal Structure Using Optical Coherence Tomography Angiography between Persons with and without HIV Infection

HIV retinal microangiopathy is an important predictor for increased risk of mortality. Optical coherence tomography angiography (OCTA) can investigate microvascular changes resulting from retinal diseases. Study included 25 persons with HIV and 25 healthy persons. OCTA evaluated the vascularization of retinal layers, choriocapillary, and optic disk. HIV group had lower vessel flow density (VFD) in superficial plexus. No difference was observed in the deep plexus. VFD of the optic disk and peripapillary region showed no difference between the groups. HIV group showed a thinner retinal nerve fiber layer and smaller area of the optic disk rim. HIV infection is associated with VFD reduction in superficial retinal plexus, neural rim area reduction, and retinal nerve fiber layer thinning in individuals without microangiopathic alterations on fundus examination. Therefore, OCTA can find retinal changes before clinical evidence of retinopathy.

HIV Infection, Antiretroviral Drugs, and the Vascular Endothelium

Endothelial cell activation, injury, and dysfunction underlies the pathophysiology of vascular diseases and infections associated with vascular dysfunction, including human immunodeficiency virus (HIV) and acquired immunodeficiency syndrome. Despite viral suppression with combination antiretroviral therapy (ART), people living with HIV (PLWH) are prone to many comorbidities, including neurological and neuropsychiatric complications, cardiovascular and metabolic diseases, premature aging, and malignancies. HIV and viral proteins can directly contribute to the development of these comorbidities. However, with the continued high prevalence of these comorbidities despite viral suppression, it is likely that ART or some antiretroviral (ARVs) drugs contribute to the development and persistence of comorbid diseases in PLWH. These comorbid diseases often involve vascular activation, injury, and dysfunction. The purpose of this manuscript is to review the current literature on ARVs and the vascular endothelium in PLWH, animal models, and in vitro studies. I also summarize evidence of an association or lack thereof between ARV drugs or drug classes and the protection or injury/dysfunction of the vascular endothelium and vascular diseases.

Hematological Complications of Human Immunodeficiency Virus (HIV) Infection: An Update From an HIV-Endemic Setting

Medical professionals, particularly in regions with a high burden of human immunodeficiency virus (HIV), should be alert to the hematological complications of HIV, which may include cytopenias, malignancy, and coagulation disturbances. Patients may present with these conditions as the first manifestation of HIV infection. Hematological abnormalities are often multifactorial with opportunistic infections, drugs, malignancy, and HIV infection itself contributing to the clinical presentation, and the diagnosis should consider all these factors. Life-threatening hematological complications requiring urgent diagnosis and management include thrombotic thrombocytopenic purpura, superior mediastinal syndrome, spinal cord compression, and tumor lysis syndrome due to aggressive lymphoma. Antiretroviral therapy is the therapeutic backbone, including for patients with advanced HIV, in addition to specific therapy for the complication. This article reviews the impact of HIV on the hematological system and provides a clinical and diagnostic approach, including the role of a bone marrow biopsy, focusing on perspectives from sub-Saharan Africa.

Endothelial dysfunction, a predictor of cardiovascular disease in HIV patients on antiretroviral therapy: A systematic review and meta-analysis

Aim Although antiretroviral therapy (ART) is available, the rate of new HIV infections is alarming. With this trend, it is anticipated that the use of ART will continue to rise, potentially resulting in associated vascular disorders. Therefore, we aimed to examine the impact of ART on endothelial function in people living with HIV (PLHIV), a predictor of cardiovascular diseases.

METHOD

A comprehensive search for evidence was made on PubMed and Scopus on May 06, 2023, following the Preferred Reporting Items for Systematic Review and Meta-analysis. Cochrane and Newcastle-Ottawa quality assessment scales were used to evaluate quality, while the metaHun web tool and Review Manager version 5.4.1 were used for analysis. Subgroup, sensitivity, and publication bias were conducted for each outcome measure.

RESULTS

We identified 37 studies, including a sample size of 3700 with 2265 individuals on ART. The analyzed evidence showed a large significant effect of ART on vascular cell adhesion molecule-1, with a standardized mean difference (SMD) of -1.23 (95 % CI: -1.72, -0.74; p = 0.0013). Similarly, a significant medium effect of ART was observed on intercellular cell adhesion molecule-1 in PLHIV, with an SMD of -1.28 (95 % CI: -2.00, -0.56; p = 0.0231) compared to the control group. Furthermore, ART exhibited a significant but small effect on flow-mediated dilation (FMD) with an SMD of -0.40 (95 % CI: -0.62, -0.19, p = 0.0159).

CONCLUSION

Our findings show an improved endothelial function in PLHIV on ART, as demonstrated by reduced adhesion molecules; however, ART exhibited a small effect on FMD, thus suggesting PLHIV on ART may still be at risk of endothelial dysfunction and further cardiovascular diseases.

Large lessons learned from small vessels: coronary microvascular dysfunction in HIV

PURPOSE OF REVIEW

Large cohort studies have consistently shown the presence of heart failure is approximately doubled among persons with HIV (PWH). Early studies of cardiovascular disease (CVD) in HIV were primarily focused on atherosclerotic burden, and we now have a greater understanding of large vessel disease in HIV. More recent studies have begun to inform us about small vessel disease, or coronary microvascular dysfunction (CMD), in HIV. CMD is recognized to be an important risk factor for adverse events related to heart failure, associated with cardiovascular mortality, and often presents without overt atherosclerotic disease.

RECENT FINDINGS

In this review, we highlight implications for CMD and relevant clinical studies in HIV. Inflammation and endothelial dysfunction, well known risk factors in HIV, may mediate the pathogenesis of CMD. Initial studies suggest that CMD worsens with ART initiation. Newer studies reveal CMD is present among well treated PWH without known CVD. In addition, myocardial flow reserve (MFR), a marker of CMD, is reduced in HIV similar to diabetes. There also appears to be sex differences, such that CMD is worse among women vs. men with HIV.

SUMMARY

Alterations in the coronary microvasculature may be an important mediator of subclinical myocardial dysfunction that deserves further clinical attention among PWH without known CVD.

Influence of physical activity on endothelial function in people living with HIV

INTRODUCTION

Decreased physical activity is a major cardiovascular risk factor that is particularly pronounced in people living with HIV (PLHIV), who are more susceptible to endothelial dysfunction and accelerated atherosclerosis than the general population due to multiple mechanisms. The aim of the present study was to analyse whether regular physical activity is capable of improving endothelial function measured by flow-mediated dilatation (FMD) in PLHIV.

METHODS

We performed FMD measurement in 38 PLHIV, along with the assessment of their regular physical activity level using the International Physical Activity Questionnaire (IPAQ).

RESULTS

Flow-mediated dilatation results in PLHIV were 0.31 ± 0.06 mm and 7.34% ± 1.41% for absolute and relative FMD, respectively. IPAQ results showed that the average weekly level of physical activity was 3631.1 ± 1526.7 MET-min/week, whereas the average daily sitting time was 287.3 ± 102.7 min/day. Predictors jointly accounted for 48% (adjusted value 42%) of FMD variance. Bootstrapped confidence levels revealed that physical activity had a statistically significant effect on the outcome [beta = 0.517, 2.5% confidence interval (CI) = 0.205, 97.5% CI = 0.752].

CONCLUSION

Physical activity represents a widely available and uncostly tool that is capable of improving endothelial function and overall cardiovascular health in PLHIV.

Coronary Microcirculatory Dysfunction in People With HIV and Its Association With Antiretroviral Therapy

BACKGROUND

HIV infection and abacavir-containing antiretroviral regimens are associated with vascular endothelial dysfunction and increased cardiovascular risk. Positron emission tomography (PET)-derived myocardial blood flow reserve (MBFR), the ratio of vasodilator stress to rest myocardial blood flow, is a well-validated measure of coronary microvascular health and marker of cardiovascular risk. Our objective was to compare MBFR among people with HIV (PWH) with matched non-HIV controls and to assess whether switching from dolutegravir/lamivudine/abacavir to the non-abacavir regimen bictegravir/emtricitabine/tenofovir alafenamide (TAF) would improve MBFR.

METHODS AND RESULTS

Thirty-seven PWH were 1:2 matched on cardiovascular risk factors to 75 people without HIV, and MBFR corrected for differences in resting hemodynamics was compared in a cross-sectional design. PWH were majority men (68%) with a mean age of 56 years. Mean stress myocardial blood flow (1.83 mL/min per g [95% CI, 1.68-1.98] versus 2.40 mL/min per g [95% CI, 2.25-2.54]; P<0.001) and MBFR (2.18 [95% CI, 1.96-2.40] versus 2.68 [95% CI, 2.47-2.89]; P=0.002) was significantly lower in PWH than in people without HIV. In a single-arm, multicenter trial, a subset of 25 PWH who were virologically suppressed on dolutegravir/lamivudine/abacavir underwent positron emission tomography myocardial perfusion imaging at baseline and after switching to bictegravir/emtricitabine/TAF. MBFR was unchanged after switching to bictegravir/emtricitabine/TAF for a mean of 27 weeks (MBFR, 2.34 to 2.29; P=0.61), except in PWH with impaired MBFR at baseline (<2.00; N=6) in whom MBFR increased from 1.58 to 2.02 (P=0.02).

CONCLUSIONS

PWH had reduced coronary microvascular function compared with controls without HIV. Coronary microvascular function did not improve after switching from dolutegravir/lamivudine/abacavir to bictegravir/emtricitabine/TAF.

REGISTRATION

URL: https://www.clinicaltrials.gov; unique identifier: NCT03656783.

Development trends of immune activation during HIV infection in recent three decades: a bibliometric analysis based on CiteSpace

This study aimed to evaluate and pinpoint the status, hot areas, and frontiers of immune activation during HIV infection utilizing CiteSpace. From 1990 to 2022, we searched for studies on immune activation during HIV infection in the Web of Science Core Collection. CiteSpace was used to visually analyze the publications to identify the research status and pertinent research hotspots and frontiers in terms of the countries, institutions, authors, references, journals, and keywords. The Web of Science Core Collection yielded 5321 articles on immune activation during HIV infection. With 2854 and 364 articles, the United States and the University of California, San Francisco were the leading nation and institution in this domain. Steven G. Deeks has published 95 papers and is the most published author. The top cited articles on microbial translocation as a significant factor during HIV infection were published by Brenchley et al. Research on molecular/biology/genetics is often referenced in publications in the journals of molecular/biology/immunology. Inflammation, risk, mortality, cardiovascular disease, persistence, and biomarkers will be high-frequency words that are hot topics of research. According to the results, there was a strong collaboration between countries and organizations but little collaboration among authors. Molecular biology, immunology, and medicine are the main study subjects. The current hot topics in research are inflammation, risk, mortality, cardiovascular disease, persistence, and biomarkers. Future studies should concentrate on reducing the pathological changes caused by inflammation and altering the mechanisms of immune activation to reduce the size of the viral reservoir.

Cardiovascular Disease and Thrombosis in HIV Infection

HIV infection has transitioned from an acute, fatal disease to a chronic one managed by antiretroviral therapy. Thus, the aging population of people living with HIV (PLWH) continues to expand. HIV infection results in a dysregulated immune system, wherein CD4+ T cells are depleted, particularly in the gastrointestinal tract, disrupting the gut epithelial barrier. Long-term HIV infection is associated with chronic inflammation through potentially direct mechanisms caused by viral replication or exposure to viral proteins and indirect mechanisms resulting from increased translocation of microbial products from the intestine or exposure to antiretroviral therapy. Chronic inflammation (as marked by IL [interleukin]-6 and CRP [C-reactive protein]) in PLWH promotes endothelial cell dysfunction and atherosclerosis. PLWH show significantly increased rates of cardiovascular disease, such as myocardial infarction (risk ratio, 1.79 [95% CI, 1.54-2.08]) and stroke (risk ratio, 2.56 [95% CI, 1.43-4.61]). In addition, PLWH have increased levels of the coagulation biomarker D-dimer and have a two to ten-fold increased risk of venous thromboembolism compared with the general population. Several small clinical trials analyzed the effect of different antithrombotic agents on platelet activation, coagulation, inflammation, and immune cell activation. Although some markers for coagulation were reduced, most agents failed to reduce inflammatory markers in PLWH. More studies are needed to understand the underlying mechanisms driving inflammation in PLWH to create better therapies for lowering chronic inflammation in PLWH. Such therapies can potentially reduce atherosclerosis, cardiovascular disease, and thrombosis rates in PLWH and thus overall mortality in this population.

HIV-Related Myocardial Fibrosis: Inflammatory Hypothesis and Crucial Role of Immune Cells Dysregulation

Although the underlying mechanisms driving human immunodeficiency virus (HIV)-mediated cardiovascular diseases (CVD) onset and progression remain unclear, the role of chronic immune activation as a significant mediator is increasingly being highlighted. Chronic inflammation is a characteristic feature of CVD and considered a contributor to diastolic dysfunction, heart failure, and sudden cardiac death. This can trigger downstream effects that result in the increased release of pro-coagulant, pro-fibrotic, and pro-inflammatory cytokines. Subsequently, this can lead to an enhanced thrombotic state (by platelet activation), endothelial dysfunction, and myocardial fibrosis. Of note, recent studies have revealed that myocardial fibrosis is emerging as a mediator of HIV-related CVD. Together, such factors can eventually result in systolic and diastolic dysfunction, and an increased risk for CVD. In light of this, the current review article will focus on (a) the contributions of a chronic inflammatory state and persistent immune activation, and (b) the role of immune cells (mainly platelets) and cardiac fibrosis in terms of HIV-related CVD onset/progression. It is our opinion that such a focus may lead to the development of promising therapeutic targets for the treatment and management of CVD in HIV-positive patients.

HIV, Combination Antiretroviral Therapy, and Vascular Diseases in Men and Women

Thanks to the advent of combination antiretroviral therapy (cART), people living with human immunodeficiency virus (HIV) (PLWH) experienced a marked increase in life expectancy but are now at higher risk for cardiovascular disease (CVD), the current leading cause of death in PLWH on cART. Although HIV preponderantly affects men over women, manifestations of HIV-related CVD differ by sex with women experiencing greater risks than men. Despite extensive investigation, the etiopathology of CVD, notably the respective contribution of viral infection and cART, remain ill-defined. However, both viral infection and cART have been reported to contribute to endothelial dysfunction, the precursor and major cause of atherosclerosis-associated CVD, through mechanisms involving endothelial cell activation, inflammation, and oxidative stress, all leading to reduced nitric oxide bioavailability. Therefore, preserving endothelial function in PLWH on cART should be a main target to reduce CVD morbidity and mortality, notably in females.

Biomarkers of Endothelial Activation in Black South African HIV-Positive Subjects are Associated with Both High Viral Load and Low CD4 Counts

The prevalence of cardiovascular death in the HIV-infected population is higher than in uninfected individuals. Growing evidence suggests that HIV infection itself is directly linked to endothelial activation and dysfunction. Therefore, the aim of this study was to investigate whether endothelial activation is present in African subjects with HIV infection and identify its possible determinants. Eighty HIV-infected treatment-naive cases, categorized into two groups based on CD4 count (38 subjects with CD4 count ≤350 cells/mm³ and 42 subjects with CD4 count >350 cells/mm³), were compared with 60 HIV-uninfected controls. A small subgroup of the HIV-infected participants (n = 13) were followed up for 18 months following initiation of antiretroviral therapy (ART). Anthropometric data, fasting lipid and glucose levels, viral load, and CD4 counts were measured as were serum levels of intercellular adhesion molecule-1 (ICAM-1), endothelial leukocyte adhesion molecule-1, vascular cell adhesion molecule-1 (VCAM-1), monocyte chemoattractant protein-1, von Willebrand factor (vWF), tumor necrosis factor alpha (TNF-α), interleukin-6 (IL-6), and interleukin-8 (IL-8). The HIV-infected low CD4 group had higher levels of ICAM-1 (p < .05), VCAM-1 (p < .0005), TNF-α (p < .005), and vWF (p < .005), compared with the controls. In the HIV-infected cohort, VCAM-1 levels were negatively associated with CD4 counts (β = -0.474; p < .0005), whereas vWF levels were positively associated with viral load (β = 0.344; p < .01). Levels of ICAM-1 and VCAM-1 were reduced by ART (p < .05 vs. baseline for both), however, levels of IL-6, IL-8, and TNF-α increased (p < .005 vs. baseline for all). Endothelial activation and inflammation are evident in African ART-naive HIV-infected patients; the former is attenuated, and the latter is increased after 18 months of ART. In HIV-infected subjects, both immunological dysregulation and viral load are associated with biomarkers of endothelial activation.

Effect of HIV-1 Infection on Angiopoietin 1 and 2 Levels and Measures of Microvascular and Macrovascular Endothelial Dysfunction

Background Individuals infected with HIV have an increased risk of developing cardiovascular disease; yet, the underlying mechanisms remain unknown. Recent evidence has implicated the Tie-2 tyrosine kinase receptor system and its associated ligands ANG1 (angiopoietin 1) and ANG2 (angiopoietin 2) in maintaining vascular homeostasis. In the general population, lower ANG1 levels and higher ANG2 levels are strongly correlated with the development of cardiovascular disease. In this study, we aim to investigate the associations of HIV infection with angiopoietin levels and endothelial dysfunction. Methods and Results In this cross-sectional study, we compared measures of ANG1, ANG2, and endothelial dysfunction using flow-mediated vasodilation of the brachial artery in 39 untreated subjects infected with HIV, 47 treated subjects infected with HIV, and 46 uninfected subjects from the SCOPE (Observational Study of the Consequences of the Protease Inhibitor Era) cohort. Compared with uninfected controls, treated individuals infected with HIV had 53.1% lower mean ANG1 levels (P<0.01) and similar ANG2 levels. On the other hand, untreated individuals infected with HIV had similar ANG1 levels, and 29.2% had higher ANG2 levels (P<0.01) compared with uninfected controls. When compared with individuals with untreated HIV infection, those with treated HIV infection had 56% lower ANG1 levels (P<0.01) and 22% lower ANG2 levels (P<0.01).Both treated and untreated HIV infection were associated with significant impairment in hyperemic velocity, a key measure of microvascular dysfunction (median 61 versus 72 cm/s, P<0.01), compared with uninfected controls (median 73 cm/s). This difference persisted after adjustment for ANG1 and ANG2 levels. Interestingly, when compared with untreated individuals infected with HIV, treated individuals infected with HIV had worse hyperemic velocity (-12.35 cm/s, P=0.05). In contrast, HIV status, ANG1 levels, and ANG2 levels were not associated with macrovascular dysfunction as measured by flow-mediated dilatation and brachial artery diameter, 2 other measures of vascular homeostasis. Conclusions HIV infection affects the balance between levels of ANG1 and ANG2 and may disturb endothelial homeostasis through disruption of vascular homeostasis. Individuals with treated HIV had decreased ANG1 levels and similar ANG2 levels, whereas individuals with untreated HIV had similar ANG1 levels and increased ANG2 levels, suggesting that treatment status may alter the balance between ANG1 and ANG2. HIV also promotes endothelial dysfunction via impairment of microvascular dysfunction, independent of the Tie-2 receptor system; the finding of worse microvascular dysfunction in the setting of treated HIV infection may reflect the impact of viral persistence on the microvasculature or toxicities of specific antiretroviral regimens. Further research to clarify the mechanism of HIV-mediated endothelial dysfunction is necessary to advance treatment of cardiovascular complications of HIV infection.

Comparison of Tolerability and Impact on Metabolic Profiles of Antiretroviral Regimens Containing Darunavir/Ritonavir or Darunavir/Cobicistat in Romanian HIV Infected Patients

The management of the side effects caused by the antiretroviral therapy is one of the main problems facing clinicians. The patient’s tolerability and safety influence the success of the therapy. This retrospective study assesses the tolerability and impact on metabolic profiles of antiretroviral regimens containing darunavir/ritonavir (DRV/r) versus those containing darunavir/cobicistat (DRV/c), in routine clinical practice. The database of Prof. Dr Matei Bals of the National Institute of Infectious Diseases (INBI MB) was studied for the period 2017–2020, allowing the inclusion in the study of 462 HIV-infected patients who received the current regimen at least three months before evaluation. The following parameters were collected and analyzed: significant medical history, associated diseases, serum levels for profile evaluation: carbohydrate, lipidic, serum level of liver and pancreatic enzymes, serum markers of cardiac function, coagulation, and renal function. DRV/c (800 mg/150 mg, once daily) administrated in combination with other antiretroviral (ARV) in HIV-1 infected subjects proved to be better tolerated and with a lower impact on metabolic profile than DRV/r (600 mg/100 mg, twice daily). Patients in DRV/r group are significantly more at risk of developing, over time, side effects and metabolic impairments than those in DRV/c group, in all body functions studied, with statistically significant differences (p < 0.05) between the two groups. Laboratory data were correlated with patient’s demographic and clinical characteristics and statistically significant outcomes have been found, proving that a personalized regimen is needed to minimize the ART side effects and to maximize the success of therapy. The results of the study showed that DRV/c, associated with other antiretroviral drugs in the regimens of Romanian HIV infected subjects, have a more favorable metabolic profile than those containing DRV/r.

Interactions of HIV and Antiretroviral Therapy With Neutrophils and Platelets

Neutrophils are important components of the innate immune system that mediate pathogen defense by multiple processes including phagocytosis, release of proteolytic enzymes, production of reactive oxygen species, and neutrophil extracellular trap formation. Abnormalities of neutrophil count and function have been described in the setting of HIV infection, with the majority of antiretroviral agents (ARVs), excluding zidovudine, having been reported to correct neutropenia. Questions still remain, however, about their impact on neutrophil function, particularly the possibility of persistent neutrophil activation, which could predispose people living with HIV to chronic inflammatory disorders, even in the presence of virally-suppressive treatment. In this context, the effects of protease inhibitors and integrase strand transfer inhibitors, in particular, on neutrophil function remain poorly understood and deserve further study. Besides mediating hemostatic functions, platelets are increasingly recognized as critical role players in the immune response against infection. In the setting of HIV, these cells have been found to harbor the virus, even in the presence of antiretroviral therapy (ART) potentially promoting viral dissemination. While HIV-infected individuals often present with thrombocytopenia, they have also been reported to have increased platelet activation, as measured by an upregulation of expression of CD62P (P-selectin), CD40 ligand, glycoprotein IV, and RANTES. Despite ART-mediated viral suppression, HIV-infected individuals reportedly have sustained platelet activation and dysfunction. This, in turn, contributes to persistent immune activation and an inflammatory vascular environment, seemingly involving neutrophil-platelet-endothelium interactions that increase the risk for development of comorbidities such as cardiovascular disease (CVD) that has become the leading cause of morbidity and mortality in HIV-infected individuals on treatment, clearly underscoring the importance of unraveling the possible etiologic roles of ARVs. In this context, abacavir and ritonavir-boosted lopinavir and darunavir have all been linked to an increased risk of CVD. This narrative review is therefore focused primarily on the role of neutrophils and platelets in HIV transmission and disease, as well as on the effect of HIV and the most common ARVs on the numbers and functions of these cells, including neutrophil-platelet-endothelial interactions.

Identification of two different coagulation phenotypes in people living with HIV with undetectable viral replication

Altered coagulation has been reported in people living with HIV (PLWH) with ongoing viral replication and may predispose to cardiovascular diseases. However, less is known about coagulation in PLWH with undetectable viral replication. In a cross-sectional observational study, we investigated whether HIV infection with undetectable viral replication is independently associated with activated partial thromboplastin time (APTT) and coagulation factor II-VII-X concentrations out of reference. Logistic regression analyses were used to assess the association of HIV infection with APTT and coagulation factor II-VII-X, after adjusting for age, sex, smoking status, alcohol consumption, BMI, diabetes and hsCRP. 936 PLWH with undetectable viral replication from the Copenhagen Co-morbidity in HIV infection study (COCOMO-study) and 2955 uninfected controls were included. Higher prevalence of short APTT was found in PLWH compared to controls (13.5% vs. 7.6%, P < 0.001). Furthermore, higher prevalence of low coagulation factor II-VII-X was found in PLWH than in controls (9.6% vs. 7.4%, P = 0.022). HIV was independently associated with short APTT (adjusted odds ratio (aOR) 2.3 (95% CI 1.7-2.9), P < 0.001) and low coagulation factor II-VII-X (aOR 1.4 (95% CI 1.0-1.9), P = 0.046). Few participants among PLWH and controls had both short APTT and low coagulation factor II-VII-X, 2.1% vs. 0.8%, respectively. We found evidence of both procoagulant (short APTT) and anticoagulant (low coagulation factor II-VII-X) alterations in PLWH with undetectable viral replication, and our findings suggest that two different coagulation phenotypes exist in participants with treated HIV infection.

Endothelial Dysfunction as a Primary Consequence of SARS-CoV-2 Infection

A number of different viral species are known to have effects on the endothelium. These include dengue, Ebola, Marburg, Lassa fever, yellow fever and influenza viruses, cytomegalovirus and coronaviruses. There are currently seven human endemic coronaviruses, all of which cause respiratory diseases and bind to receptors found within the endothelium. The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that causes the coronavirus disease 2019 (COVID-19) is highly infectious. Like its predecessor, SARS-CoV, it binds to angiotensin-converting enzyme-2 (ACE-2), which is expressed in many cell types, particularly in the lung, including endothelial cells. The initiation of a cytokine storm by the virus along with infection of endothelial cells leads to apoptosis and structural and functional changes that attenuate vascular integrity in many organs including the lungs, heart, liver and kidney. Endothelial damage also enhances the coagulation pathway leading to thrombus formation in major vessels and capillaries. Infection with SARS-CoV-2 has an adverse outcome for individuals with particular comorbid diseases, e.g. hypertension, obesity, type 2 diabetes and cardiovascular disease. It is possible that this is due to the presence of pre-existing endothelial dysfunction and systemic inflammation in subjects with these diseases. Therapies for COVID-19 that target the endothelium, the inflammatory response and the coagulation pathway are currently under trial.

Do Combination Antiretroviral Therapy Regimens for HIV Infection Feature Diverse T-Cell Phenotypes and Inflammatory Profiles?

Immune abnormalities featuring HIV infection persist despite the use of effective combination antiretroviral therapy (cART) and may be linked to the development of noninfectious comorbidities. The aim of the present narrative, nonsystematic literature review is to understand whether cART regimens account for qualitative differences in immune reconstitution. Many studies have reported differences in T-cell homeostasis, inflammation, coagulation, and microbial translocation parameters across cART classes and in the course of triple vs dual regimens, yet such evidence is conflicting and not consistent. Possible reasons for discrepant results in the literature are the paucity of randomized controlled clinical trials, the relatively short follow-up of observational studies, the lack of clinical validation of the numerous inflammatory biomarkers utilized, and the absence of research on the effects of cART in tissues. We are currently thus unable to establish if cART classes and regimens are truly accountable for the differences observed in immune/inflammation parameters in different clinical settings. Questions still remain as to whether an early introduction of cART, specifically in the acute stage of disease, or newer drugs and novel dual drug regimens are able to significantly impact the quality of immune reconstitution and the risk of disease progression in HIV-infected subjects.

Endothelial dysfunction and carotid atherosclerosis in Malawian adults: A cross-sectional study

Background and objective

In sub-Saharan Africa, data on prevalence, risk factors and pathobiology of carotid atherosclerosis are scarce. We aimed to investigate the relationship between biomarkers of endothelial dysfunction and carotid atherosclerosis.

Methods

Carotid ultrasound was performed in 66 patients. Plasma concentration of ICAM-1, PAI-1, VEGF, and soluble thrombomodulin were measured by ELISA. A univariable logistic regression analysis was performed to study the relationship between carotid atherosclerosis, biomarkers of endothelial dysfunction, and various demographic and clinical parameters of the participants.

Results

The mean age of the participants was 58.7 years (95% CI: 54.4-63.1). Carotid atherosclerosis was diagnosed in 39.4% (95% CI: 27.6-52.2). In the univariable logistic regression, the following factors were associated with carotid atherosclerosis: age > 45 years (OR = 12.0, 95% CI: 1.4-98.8, p = .02), hypertension (OR = 3.8, 95% CI: 1.2-12.1, p = .02), and high-level of soluble thrombomodulin (OR = 3.4, 95% CI: 1.2-10.0, p = .02).

Conclusions

There is an association between high levels of soluble thrombomodulin and carotid atherosclerosis in Malawian adults. Further studies with a larger sample size are needed to confirm our findings in other African populations.

Cardiovascular risk and D-dimer levels in HIV-infected ART-naïve Africans

Anti-retroviral therapy (ART) has decreased morbidity and mortality in HIV-infected individuals. With the adoption of the 90-90-90 strategy prevention and control of non-communicable disease, particularly knowledge of the burden and profile of cardiovascular disease, will become increasingly important. Our study assessed cardiovascular risk among recently diagnosed HIV-infected ART-naïve patients in a first referral urban hospital in a low-income country in sub-Saharan Africa. HIV-positive ART-naïve patients were submitted to cardiovascular risk assessment, clinical history, physical examination and laboratory workout, including 12-lead electrocardiography, portable transthoracic echocardiography, glycemia, lipidemia, hemogram and D-dimers. Three years after the diagnosis their vital status and occurrence of major cardiovascular events was assessed. We recruited 70 patients, all of black ethnicity (41 females; mean age 37±10.7). CD4 levels were very low (mean 21.3 cells/mL; SD 10.4). Twenty-one (26.6%) were overweight, 13 (16.7%) were obese, 19 (20.5%) had hyperglycemia and 20 patients (25.6%) had hypercholesterolemia. The median blood pressure was 119.5/79 mmHg (IQR 107-141/67-83); 20 patients (25.6%) had hypertension. Four (5.7%) patients had signs of heart failure, and left ventricular ejection fraction was reduced in 17 (25%). High levels of circulating D-dimers were found in 44 (62.8%) patients; the mean levels were 725.9 (SD 555.1). We found high occurrence of cardiovascular risk factors, left ventricular dysfunction and evidence of a pro-coagulant state in these HIV-infected ART-naïve patients. Active cardiovascular risk screening and stratification, as well as management protocols tailored to low-income settings are needed to sustain the gains obtained with increased availability of ART in Africa.

HIV-related cardiovascular diseases: the search for a unifying hypothesis

Although the extensive rollout of antiretroviral (ARV) therapy resulted in a longer life expectancy for people living with human immunodeficiency virus (PLHIV), such individuals display a relatively increased occurrence of cardiovascular diseases (CVD). This health challenge stimulated significant research interests in the field, leading to an improved understanding of both lifestyle-related risk factors and the underlying mechanisms of CVD onset in PLHIV. However, despite such progress, the precise role of various risk factors and mechanisms underlying the development of HIV-mediated CVD still remains relatively poorly understood. Therefore, we review CVD onset in PLHIV and focus on 1) the spectrum of cardiovascular complications that typically manifest in such persons and 2) underlying mechanisms that are implicated in this process. Here, the contributions of such factors and modulators and underlying mechanisms are considered in a holistic and integrative manner to generate a unifying hypothesis that includes identification of the core pathways mediating CVD onset. The review focuses on the sub-Saharan African context, as there are relatively high numbers of PLHIV residing within this region, indicating that the greater CVD risk will increasingly threaten the well-being and health of its citizens. It is our opinion that such an approach helps point the way for future research efforts to improve treatment strategies and/or lifestyle-related modifications for PLHIV.

Hemostasis in elderly patients with human immunodeficiency virus (HIV) infection-Cross-sectional study

Introduction: Aging and chronic HIV infection are clinical conditions that share the states of inflammation and hypercoagulability. The life expectancy of the world population has increased in the last decades, bringing as complications the occurrence of diseases that undergoing metabolic, bone, cardiological, vascular and neurological alterations. HIV-infected patients experience these changes early and are living longer due to the success of antiretroviral therapy. The objectives of this study was to evaluate some changes in the plasma hemostatic profile of 115 HIV-reactive elderly individuals over 60 years old in the chronic phase of infection, and compare with 88 healthy uninfected elderly individuals. Plasma determinations of D-dimers, Fibrinogen, von Willebrand Factor, Antithrombin, Prothrombin Time, Activated Partial Thromboplastin Time, and platelet count were performed. In the HIV-reactive group, these variables were analyzed according to viral load, protease inhibitor use and CD4⁺ T lymphocyte values. After adjusted values for age and sex, the results showed higher levels of Antithrombin (103%; 88%, p = 0.0001) and Prothrombin Time activities (92.4%; 88.2%, p = 0.019) in the HIV group compared to the control group. We observed higher values of Fibrinogen in protease inhibitor users in both the male (p = 0.043) and female (p = 0.004) groups, and in the female HIV group with detected viral load (p = 0.015). The male HIV group with a CD4⁺ count> 400 cells / mm³ presented higher von Willebrand Factor values (p = 0.036). D-Dimers had higher values in the older age groups (p = 0.003; p = 0.042, respectively). Conclusion: Our results suggest that the elderly with chronic HIV infection with few comorbidities had a better hemostatic profile than negative control group, reflecting the success of treatment. Protease inhibitor use and age punctually altered this profile.

Deciphering Endothelial Dysfunction in the HIV-Infected Population

Cardiovascular disease (CVD), as a possible consequence of endothelial dysfunction, is prevalent among HIV-infected patients despite successful administration of antiretroviral drugs. This warrants the routine clinical assessment of endothelial function in HIV-positive patients to circumvent potential CVD events. Several different non-invasive strategies have been employed to assess endothelial function in clinical research studies yielding inconsistencies among these reports. This review summarises the different techniques used for assessing endothelial function, with a focus on proposed blood-based biomarkers, such as endothelial leukocyte adhesion molecule-1 (E-selectin), soluble intercellular adhesion molecule-1 (sICAM-1), soluble vascular cell adhesion molecule-1 (sVCAM-1), von Willebrand factor (vWF), TNF-α, interleukin 6 (IL6) and soluble thrombomodulin (sTM). The identification of suitable blood-based biomarkers, especially those that can be measured using a point-of-care device, would be more applicable in under-resourced countries where the prevalence of HIV is high.

Vorapaxar for HIV-associated inflammation and coagulopathy (ADVICE): a randomised, double-blind, placebo-controlled trial

BACKGROUND

Increased D-dimer concentrations are associated with poor cardiovascular and other clinical outcomes in people with treated HIV infection. Proteinase activated receptor-1 (PAR-1) is activated by thrombin and overexpressed by immune cells from HIV-infected people. We aimed to study the efficacy of vorapaxar, a licensed inhibitor of PAR-1, in reducing HIV-associated hypercoagulation and inflammation.

METHODS

This was a multicentre, double-blind, randomised, placebo-controlled trial done in seven hospital clinics in Australia and the USA. Eligible participants were HIV-infected, aviraemic, were receiving stable antiretroviral therapy, and had D-dimer concentrations greater than 200 ng/mL. We randomly assigned participants (1:1) using computer-generated block lists of size two to receive vorapaxar (2·5 mg orally daily) or matched placebo for 12 weeks. Participants were reviewed and had a blood sample taken at weeks 1, 4, 8, and 12 during treatment, and at a final visit at week 18. The primary endpoint was treatment group difference in changes from baseline D-dimer concentrations after 8-12 weeks of treatment, and was assessed in the modified intention-to-treat population (participants who had at least one dose of study drug or one follow-up visit). This trial is registered with ClinicalTrials.gov, number NCT02394730, and is closed to new participants.

FINDINGS

Between Oct 21, 2015, and July 14, 2017, 65 eligible patients were randomly assigned to the placebo group (n=31) or vorapaxar group (n=34). One patient from the vorapaxar group did not receive any study drug, and the modified intention-to-treat population was comprised of 33 patients. D-dimer concentrations after 8-12 weeks of treatment did not differ significantly between groups (difference -0·02 log10 ng/mL, 95% CI -0·10 to 0·05; p=0·56). Vorapaxar treatment was safe and well tolerated in this cohort. There were 161 adverse events (n=84 in the placebo group and n=77 in the vorapaxar group), and five protocol-defined serious adverse events that required hospital admission for more than 24 h (n=2 in the placebo group and n=3 in the vorapaxar group). One patient ceased taking vorapaxar because of an adverse event. There were 25 bleeding events, 23 of which were mild, one was moderate, and one was severe.

INTERPRETATION

Vorapaxar had no effect on D-dimer concentrations in HIV-infected patients receiving stable antiretroviral therapy but at risk of poor outcomes. Alternative approaches are needed to reduce hypercoagulation, inflammation, and adverse long-term outcomes in patients with treated HIV infection.

FUNDING

Australian National Health and Medical Research Council, US National Cancer Institute, National Institutes of Health.

Cardiovascular Disease in the Setting of Human Immunodeficiency Virus Infection

Background:

Since the introduction of Antiretroviral Therapy (ART), the life expectancy and health quality for patients infected with Human Immunodeficiency Virus (HIV) have significant-ly improved. Nevertheless, as a result of not only the deleterious effects of the virus itself and pro-longed ART, but also the effects of aging, cardiovascular diseases have emerged as one of the most common causes of death among these patients.

Objective:

The purpose of this review is to explore the new insights on the spectrum of Cardiovascu-lar Disease (CVD) in HIV infection, with emphasis on the factors that contribute to the atherosclerot-ic process and its role in the development of acute coronary syndrome in the setting of infection.

Methods:

A literature search using PubMed, ScienceDirect and Web of Science was performed. Ar-ticles up to Mar, 2017, were selected for inclusion. The search was conducted using MeSH terms, with the following key terms: [human immunodeficiency virus AND (cardiovascular disease OR coronary heart disease) AND (antiretroviral therapy AND (cardiovascular disease OR coronary heart disease))].

Results:

Clinical cardiovascular disease tends to appear approximately 10 years before in infected in-dividuals, when compared to the general population. The pathogenesis behind the cardiovascular, HIV-associated complications is complex and multifactorial, involving traditional CVD risk factors, as well as factors associated with the virus itself - immune activation and chronic inflammation – and the metabolic disorders related to ART regimens.

Conclusion:

Determining the cardiovascular risk among HIV-infected patients, as well as targeting and treating conditions that predispose to CVD, are now emerging concerns among physicians.

Basic Coagulation Parameters among Human Immunodeficiency Virus-Infected Adults in Gondar, Northwest Ethiopia: A Comparative Cross-Sectional Study

Objective

We aimed at assessing the basic coagulation parameters of HIV-infected adults at the University of Gondar Hospital antiretroviral therapy clinic.

Methods

A comparative cross-sectional study was conducted from February to May 2017. A total of 300 study participants, consisting of 100 HAART-naïve HIV-infected adults, 100 HIV-infected adults who were taking HAART, and 100 HIV-seronegative apparently healthy adults, were included. Basic coagulation functional assays such as PT, APTT, and INR were determined by coagulation analyzer. CD4 cells and platelet count were analyzed by FACS count and SYSMEX K-21N automated analyzer, respectively. The data were entered, cleaned, and edited using Epi Info version 7 and analyzed using SPSS version 20. Kruskal-Wallis H, Dunn-Bonferroni pairwise comparison test, and Spearman's rank-order correlation analysis were used for inferential statistics. The results were expressed by a median and presented in tables. P value < 0.05 was considered as statistically significant.

Results

PT, APTT, and INR were significantly higher, whereas platelet count was significantly lower in HIV-infected adults (both who were taking HAART and HAART-naïve) than HIV-seronegative adults (P < 0.001). PT and INR were significantly higher, and platelet count was significantly lower in HAART-naïve HIV-infected adults than HIV-infected adults who were taking HAART. In Spearman's rank-order correlation analysis, APTT has shown a significant negative correlation with a CD4 count in HAART-naïve HIV-infected adults.

Conclusion

HIV-infected adults are more likely to develop coagulation abnormality than HIV-seronegative subjects. Coagulation parameters need to be checked regularly to monitor coagulation disorders in HIV-infected adults.

Pathogenic factors associated with development of disseminated intravascular coagulopathy (DIC) in a tertiary academic hospital in South Africa

Introduction

Disseminated intravascular coagulopathy (DIC) is a thrombotic microangiopathy arising from consumption of both coagulation factors and platelets. DIC is triggered by a number of clinical conditions including severe infection, trauma and obstetric complications. Early diagnosis and treatment of the underlying condition is paramount. A high clinical index of suspicion is needed to ensure that patients at risk of developing DIC are appropriately investigated.

Methods

In order to establish the clinical conditions most frequently associated with DIC, we reviewed all DIC screens received at a tertiary hospital in Johannesburg, South Africa over a 1 year period.

Results

The commonest clinical condition associated with DIC in our population was infection with 84% of patients infected with an identified pathogen. The most frequently diagnosed pathogen was HIV followed by Mycobacterium tuberculosis and other bacterial infections. In the majority of cases, bacteria were isolated from blood cultures. In 47 patients, HIV was the only pathogen which could be isolated. A relative risk ratio of 2.73 and an odds ratio of 29.97 was attributed to HIV for development of a DIC. A malignancy was present in 51 of the patients of which approximately 60% had co-existing infection. No cause could be attributed in 30 patients.

Conclusion

Infection was identified in the majority of the patients diagnosed with DIC in this study. HIV showed the highest relative risk ratio of all pathogens although previous studies have not suggested that HIV was strongly associated with DIC. In almost half of the HIV infected patients, there was no other pathogen isolated despite extensive investigation. This suggests that HIV has a strong association with the development of DIC, warranting further research into the relationship between HIV and disseminated microvascular thrombosis.

[Arterial hemodynamic parameters and cardiovascular risk in HIV patients with controlled infection]

Although viral replication is apparently controlled with highly active antiretroviral therapy, cardiovascular risk of patients living with HIV remains a concern in clinical practice with population ageing. Cardiovascular risk profile in patients living with HIV is changing with the emergence of new parameters related to the persistence of residual viral replication, the antecedent and severity of immunodepression, the resulting chronic inflammation, as well as prolonged exposure to antiretroviral drugs and "classical" cardiovascular risk factors. Estimating risk models in patients living with HIV are not sufficient to integrate duration of exposure and control quality of all cardiovascular risk factors at the individual level. Aortic stiffness is a marker of the alteration of structural and functional properties of the wall of the large arterial trunks. This marker has an independent predictive value for total and cardiovascular mortality in the general population but also in the presence of risk factors and may offer clinical information about accelerated vascular ageing in people living with HIV. Aortic stiffness can be estimated non-invasively by applanation tonometry with carotid-femoral pulse wave velocity. This measure may be useful in clinical practice for early identification of at risk patients. Study of the determinants of aortic stiffening process in this population may optimize cardiovascular prevention.

Effects of antiretroviral treatment and nadir CD4 count in progression to cardiovascular events and related comorbidities in a HIV Brazilian cohort: a multi-stage approach

The use of highly active antiretroviral therapy has resulted in changes of comorbidity profile in people living with HIV (PLHIV), increasing non-AIDS-related events. The occurrence of cardiovascular events is greater in PLHIV, but the mechanism responsible for it is still controversial. This article aimed to investigate factors associated with the progression to cardiovascular events in PLHIV using HAART. A 15-years cohort study with 1135 PLHIV was conducted in Rio de Janeiro-Brazil. Clinical progression was stratified in five states: No comorbidities (s₁), arterial hypertension (s₂), lipid abnormalities (s₃), hypertension and lipid abnormalities (s₄) and major cardiovascular events (stroke, coronary artery disease, thrombosis or death) (s₅). Semi-Markov models evaluated the effects of cardiovascular traditional factors, treatment and clinical covariates on transitions between these states. Hazard Ratios (HR) and 95% confidence intervals (CI) were provided. In addition to traditional factors (age, sex, educational level and skin color), the development of one comorbidity (lipid abnormalities or hypertension) increased in patients with low nadir CD4 (<50 cells/mm³), (HR = 1.59, CI 1.11-2.28 and 1.36, CI 1.11-1.66, respectively). The risk to experience a second comorbidity (s₃→s₄) increased 75% with low nadir CD4. Age was the only factor that increased the risk of major cardiovascular events once having lipid abnormalities with or without hypertension (s₃,s₄→s₅). The prolonged use of certain antiretroviral drugs (abacavir, didanosine, ritonavir, lopinavir, amprenavir and fosamprenavir) increased the risk of direct transition (s₁→s₅) to major cardiovascular events (HR = 5.29, CI 1.16-24.05). This analysis suggests that prolonged use of certain antiretroviral drugs led directly to major cardiovascular events, while low nadir CD4 only affected the occurrence of lipid abnormalities and hypertension. Management strategies, including rational use of complex exams (such as, computed-tomography angiography), statins and antihypertensives, should be developed based on the distinct roles of antiretroviral use and of HIV infection itself on the progression to cardiovascular events.

HIV infection, antiretroviral therapy, and measures of endothelial function, inflammation, metabolism, and oxidative stress

Background

HIV-infected patients have an increased risk of cardiovascular disease (CVD). Impaired endothelial function is an early risk factor for CVD in the general population. It is presumed that HIV infection is associated with impaired endothelial function, but results have been inconsistent.

Objectives

Our objectives were to determine the relationships between HIV infection, virologic suppression with antiretroviral therapy (ART), in vivo measures of conduit artery and microvascular endothelial function, and circulating biomarkers of pathways associated with CVD.

Methods

We performed a cross-sectional analysis of three prospectively enrolled groups from a single center: 28 were HIV-infected and virologically-suppressed on a regimen of FTC/TDF/EFV (HIV+ART+), 44 were HIV-infected but not on ART (HIV+ART-), and 39 were HIV-uninfected healthy volunteers (HIV-) matched to the HIV+ART- group for age, sex, smoking status, and height. None had diabetes, uncontrolled hypertension, known CVD, or other pro-inflammatory condition. Flow mediated dilation (FMD), nitroglycerin-mediated dilation (NTGMD), reactive hyperemia velocity time integral (RHVTI), and FMD/RHVTI of the brachial artery were measured, as well as circulating biomarkers of systemic inflammation, metabolism, oxidative stress, and endothelial activation.

Results

No significant differences were found amongst the three groups in FMD (P = 0.46), NTGMD (P = 0.42), RHVTI (P = 0.17), and FMD/RHVTI (P = 0.22) in unadjusted comparisons. Adjusted ANOVA models which included brachial artery diameter, demographics, and conventional CVD risk factors did not appreciably change these findings. In pairwise comparisons, the HIV+ART- group had significantly higher soluble tumor necrosis factor receptor II, soluble CD163, β-2 microglobulin, interferon-γ- induced protein-10, tissue inhibitor of metalloproteinase-1, and vascular cell adhesion molecule-1 compared to the other two groups (all p<0.05). Correlates of endothelial function differed between study groups.

Conclusion

Although untreated HIV infection was associated with elevated levels of several biomarkers of inflammation and endothelial activation, we were unable to demonstrate differences in measures of conduit artery and microvascular endothelial function in this study population.

Analysis of Retinochoroidal Vasculature in Human Immunodeficiency Virus Infection Using Spectral-Domain OCT Angiography

PURPOSE

To describe the retinochoroidal vascular alterations in patients with human immunodeficiency virus (HIV) infection using en face OCT angiography (OCTA).

DESIGN

Cross-sectional study.

PARTICIPANTS

Twenty-six patients with HIV infection (5 women, with and without HIV retinopathy) were included in the study. Nineteen healthy participants (7 women) with no known ocular disease were recruited as healthy controls.

METHODS

Multimodal imaging was performed using OCTA (Optovue RTVue XR Avanti; Optovue, Inc, Fremont, CA), enhanced-depth imaging OCT (Heidelberg Spectralis; Heidelberg Engineering, Heidelberg, Germany), color fundus photography, and fluorescein angiography (FA). Vessel flow density (VFD) was calculated automatically by the OCTA software. Morphologic changes in the retinochoroidal vasculature in the posterior pole on OCTA were assessed by 2 trained independent graders and were compared with the findings on clinical examination and other imaging techniques.

MAIN OUTCOME MEASURES

Prevalence of microvascular alterations on OCTA among patients with HIV and differences in the VFD in different macular sectors compared with healthy controls.

RESULTS

Among all eyes with clinically detectable HIV retinopathy, there was evidence of retinal vascular telangiectasia, capillary loops, and increased intercapillary spacing. The mean VFD values were lower among patients with HIV retinopathy compared with those with HIV and no retinopathy and healthy controls (both P < 0.05). Foveal avascular zone area was abnormally enlarged among patients with HIV compared with healthy controls (P = 0.05). Five eyes (23.53%) without clinical or angiographic evidence of retinopathy demonstrated retinal vascular telangiectasia and increased intercapillary spacing on OCTA. The inner choroidal vasculature appeared to be mostly unaffected in HIV.

CONCLUSIONS

OCT angiography provides noninvasive high-resolution imaging of the retinochoroidal vascular network in patients with HIV. Compared with conventional imaging, OCTA can demonstrate precise microvascular structural alterations in the retinal vessels and seems to be a sensitive tool in detecting HIV retinopathy.

Coagulation imbalance and neurocognitive functioning in older HIV-positive adults on suppressive antiretroviral therapy

OBJECTIVES

The aim of this study was to compare plasma biomarkers of coagulation between HIV-infected individuals and HIV-uninfected controls and to assess the impact of disturbances in coagulation on neurocognitive functioning in HIV.

DESIGN

A cross-sectional study of 66 antiretroviral therapy treated, virally suppressed, HIV-infected and 34 HIV-uninfected older (≥50 years of age) adults.

METHODS

Participants completed standardized neurobehavioral and neuromedical assessments. Neurocognitive functioning was evaluated using a well validated comprehensive neuropsychological battery. Plasma biomarkers associated with procoagulation (fibrinogen, p-selectin, tissue factor and von Willebrand factor), anticoagulation (antithrombin, protein C and thrombomodulin), fibrinolysis (d-dimer, plasminogen activator inhibitor-1 and plasminogen) were collected. Multivariable linear regression was used to test the interaction of HIV and coagulation on neurocognitive functioning.

RESULTS

Most participants were male (78.0%) and non-Hispanic white (73.0%) with a mean age of 57.8 years. Among HIV-infected participants, mean estimated duration of HIV infection was 19.4 years and median current CD4 cell count was 654 cells/μl. Levels of soluble biomarkers of procoagulation, anticoagulation and fibrinolysis were comparable between the HIV serostatus groups. Coagulation and HIV had an interacting effect on neurocognitive functioning, such that greater coagulation imbalance was associated with poorer neurocognitive functioning among the HIV-infected participants. The moderating effect of coagulation on neurocognition was driven by procoagulant but not anticoagulant or fibrinolytic biomarkers.

CONCLUSIONS

Elevated levels of procoagulants may exert a particularly detrimental effect on neurocognitive functioning among older HIV-infected persons. A better understanding of the specific role of coagulation in the cause of HIV-associated neurocognitive disorders may lead to treatments aimed at reducing coagulopathy, thereby improving neurocognitive outcomes.

Recent advances in understanding hypertension development in sub-Saharan Africa

Consistent reports indicate that hypertension is a particularly common finding in black populations. Hypertension occurs at younger ages and is often more severe in terms of blood pressure levels and organ damage than in whites, resulting in a higher incidence of cardiovascular disease and mortality. This review provides an outline of recent advances in the pathophysiological understanding of blood pressure elevation and the consequences thereof in black populations in Africa. This is set against the backdrop of populations undergoing demanding and rapid demographic transition, where infection with the human immunodeficiency virus predominates, and where under and over-nutrition coexist. Collectively, recent findings from Africa illustrate an increased lifetime risk to hypertension from foetal life onwards. From young ages black populations display early endothelial dysfunction, increased vascular tone and reactivity, microvascular structural adaptions as well as increased aortic stiffness resulting in elevated central and brachial blood pressures during the day and night, when compared to whites. Together with knowledge on the contributions of sympathetic activation and abnormal renal sodium handling, these pathophysiological adaptations result in subclinical and clinical organ damage at younger ages. This overall enhanced understanding on the determinants of blood pressure elevation in blacks encourages (a) novel approaches to assess and manage hypertension in Africa better, (b) further scientific discovery to develop more effective prevention and treatment strategies and

Role of T-Cell Dysfunction, Inflammation, and Coagulation in Microvascular Disease in HIV

BACKGROUND

Compared to uninfected adults, HIV-infected adults on antiretroviral therapy are at increased risk of cardiovascular disease. Given the increase in T-cell dysfunction, inflammation, and coagulation in HIV infection, microvascular dysfunction is thought to contribute to this excess cardiovascular risk. However, the relationships between these variables remain undefined.

METHODS AND RESULTS

This was a cross-sectional study of 358 HIV-infected adults from the SCOPE cohort. Macrovascular endothelial function was assessed using flow-mediated dilation of the brachial artery and microvascular function by reactive hyperemia. T-cell phenotype was determined by flow cytometry. Plasma markers of inflammation (tumor necrosis factor-α, interleukin-6, high-sensitivity C-reactive protein, sCD14) and coagulation (fibrinogen, D-dimer) were also measured. In all HIV+ subjects, markers of inflammation (tumor necrosis factor-α, high-sensitivity C-reactive protein), coagulation (D-dimer) and T-cell activation (CD8+PD1+, CD4+interferon+cytomegalovirus-specific) were associated with worse reactive hyperemia after adjusting for traditional cardiovascular risk factors and co-infections. In treated and suppressed subjects, tumor necrosis factor-α and CD8+PD1+ cells remained associated with worse reactive hyperemia after adjustment. Compared to the untreated subjects, CD8+PD1+ cells were increased in the virally suppressed group. Reactive hyperemia was predictive of flow-mediated dilation.

CONCLUSIONS

CD8+PD1+ cells and tumor necrosis factor-α were associated with microvascular dysfunction in all HIV+ subjects and the treated and suppressed group. Additionally, D-dimer, high-sensitivity C-reactive protein, sCD-14, and interleukin-6 were associated with microvascular dysfunction in all HIV+ subjects. Although T-cell dysfunction, inflammation, and microvascular dysfunction are thought to play a role in cardiovascular disease in HIV, this study is the first to look at which T-cell and inflammatory markers are associated with microvascular dysfunction in HIV-infected individuals.

Associations between antiretroviral use and subclinical coronary atherosclerosis

OBJECTIVES

HIV infection is associated with increased prevalence of subclinical coronary plaque. The extent to which such plaque reflects effects of HIV infection or effects of long-term antiretroviral therapy (ART) use remains unclear and was the goal of this analysis.

DESIGN AND METHODS

We compared the prevalence and extent of coronary plaque and stenosis between users of specific ART drugs or drug classes using coronary computed tomography (CT) among HIV-infected men in the Multicenter AIDS Cohort Study. To account for time-dependent confounders, including cardiovascular disease risk factors and time-varying reasons for using specific treatments, we conducted fully adjusted logistic and linear models with inverse probability of treatment weighting.

RESULTS

There were 618 men who underwent noncontrast coronary CT; 450 also underwent coronary CT angiography. At the time of scanning, 81% had undetectable plasma HIV RNA. In fully adjusted models, cumulative use of zidovudine, abacavir, darunavir, and protease inhibitors as a drug class were inconsistently associated with specific forms of plaque presence or extent.

CONCLUSION

Among virally suppressed HIV-infected men with extensive ART exposure, no consistent associations between use of specific ART drugs and both subclinical coronary plaque presence and extent were apparent. Our findings support the hypothesis that, among virally suppressed persons, type of ART used is not in general a major determinant of subclinical coronary plaque risk.

Novel relationships of markers of monocyte activation and endothelial dysfunction with pulmonary dysfunction in HIV-infected persons

OBJECTIVE

Chronic obstructive pulmonary disease is a common comorbidity in HIV, with prevalence and severity of disease incompletely explained by risk factors such as smoking and age. Unique HIV-associated factors, including microbial translocation, monocyte activation, and endothelial dysfunction, have been described in other comorbidities, but have not been investigated in relation to pulmonary abnormalities in HIV. This study assessed the relationship of these pathologic processes to pulmonary function in HIV-infected and uninfected individuals and determined if relationships were unique to HIV.

DESIGN

Longitudinal observational study.

METHODS

Total 274 participants completed pulmonary function testing. Markers of inflammation (IL-6, IL-8, and TNFα), microbial translocation (lipopolysaccharide, sCD14), monocyte activation (sCD163, sCD14, and IL-2 receptor), and endothelial dysfunction (endothelin-1) were measured at baseline. Cross-sectional and longitudinal analyses were performed, adjusting for pertinent covariates.

RESULTS

In HIV-infected individuals, higher IL-6 and endothelin-1 associated with worse forced expiratory volume in one second (FEV1) percentage-predicted, and higher sCD163 associated with worse FEV1/forced vital capacity. IL-6, TNFα, lipopolysaccharide, sCD163, IL-2 receptor, and endothelin-1 associated with diffusing impairment. sCD163 and endothelin-1 interacted with HIV status in relationship to pulmonary function. In HIV-infected individuals only, baseline endothelin-1 was associated with lower FEV1, and sCD163 and endothelin-1 were associated with lower diffusing capacity during follow-up.

CONCLUSION

Circulating markers of HIV-associated humoral abnormalities are associated with airflow obstruction and diffusing impairment and baseline measures of monocyte activation and endothelial dysfunction associate with lower pulmonary function over time in HIV-infected persons. These findings suggest mechanisms of the disproportionate burden of chronic obstructive pulmonary disease in HIV-infected persons.

What happens to cardiovascular system behind the undetectable level of HIV viremia?

Despite the combined antiretroviral therapy has improved the length and quality of life of HIV infected patients, the survival of these patients is always decreased compared with the general population. This is the consequence of non-infectious illnesses including cardio vascular diseases. In fact large studies have indicated an increased risk of coronary atherosclerotic disease, myocardial infarction even in HIV patients on cART. In HIV infected patients several factors may contribute to the pathogenesis of cardiovascular problems: life-style, metabolic parameters, genetic predisposition, viral factors, immune activation, chronic inflammation and side effects of antiretroviral therapy. The same factors may also contribute to complicate the clinical management of these patients. Therefore, treatment of these non-infectious illnesses in HIV infected population is an emerging challenge for physicians. The purpose of this review is to focus on the new insights in non AIDS-related cardiovascular diseases in patients with suppressed HIV viremia.

TestMeEast: a campaign to increase HIV testing in hospitals and to reduce late diagnosis

Late diagnosis occurs in almost half of those diagnosed in the UK (HIV Prevention England, 2013. Retrieved June 22, 2014, from HIV Prevention England: http://www.hivpreventionengland.org.uk/Campaigns-Current/National-HIV-Testing-Week ). Testing occurs mainly in sexual health and antenatal clinics despite recommendations to test more broadly [Ellis, S., & Curtis, H. (2012). HIV diagnoses and missed opportunities. Results of the British HIV association (BHIVA) National Audit 2010. Clinical Medicine, 12(5), 430-434]. We report the findings of an HIV-testing week campaign to offer testing to those who have blood tests as part of routine care within outpatient clinics and emergency departments of six London hospitals. The campaign target was to test 500 patients a day during the 2013 National HIV Testing Week (NHTW). Clinic staff and medical students were trained to offer routine HIV testing. Linkage to care was arranged for those who tested HIV-positive. During NHTW we tested 2402 of the planned 2500 test target. 2402/4317 (55.6% 95% CI 54.1-57.1%) of those who had routine blood tests were tested for HIV. There were eight HIV-positive tests; three were new diagnoses (all linked to care). The campaign hashtag #TestMeEast achieved a total Twitter "reach" of 238, 860 and the campaign had widespread news coverage. Our campaign showed that staff and students could be trained and mobilised to do thousands of routine HIV tests during a campaign.

Immune activation in the course of HIV-1 infection: Causes, phenotypes and persistence under therapy

Systemic immune activation is a striking consequence of HIV-1 infection. Even in virologically suppressed patients, some hyperactivity of the immune system and even of the endothelium and of the coagulation pathway may persist. Apart from immune deficiency, this chronic activation may contribute to various morbidities including atherothrombosis, neurocognitive disorders, liver steatosis and osteoporosis, which are currently main challenges. It is therefore of major importance to better understand the causes and the phenotypes of immune activation in the course of HIV-1 infection. In this review we will discuss the various causes of immune activation in HIV-1 infected organisms: the presence of the virus together with other microbes, eventually coming from the gut, CD4+ T cell lymphopenia, senescence and dysregulation of the immune system, and/or genetic factors. We will also describe the activation of the immune system: CD4+ and CD8+ T cells, B cells, NKT and NK cells, dendritic cells, monocytes and macrophages, and neutrophils of the inflammation cascade, as well as of the endothelium and the coagulation system. Finally, we will see that antiretroviral therapy reduces the hyperactivity of the immune and coagulation systems and the endothelial dysfunction, but often does not abolish it. A better knowledge of this phenomenon might help us to identify biomarkers predictive of non AIDS-linked comorbidities, and to define new strategies aiming at preventing their emergence.

Is the atherosclerotic process accentuated under conditions of HIV infection, antiretroviral therapy, and protease inhibitor exposure? Meta-analysis of the markers of arterial structure and function

OBJECTIVE

To evaluate the apparent association of human immunodeficiency virus (HIV) infection, antiretroviral therapy (ART), and protease inhibitor (PI) exposure with the functional and structural markers of vasculature.

METHODS

A meta-analysis of the relationship between HIV infection, ART, and PI exposure and the functional and structural markers of vasculature. A systematic literature search was performed electronically using specific eligibility criteria. Weighted mean difference (WMD) and corresponding 95% confidence interval (CI) were calculated and combined appropriately.

RESULTS

Fifty-seven articles were included with nine different outcomes. Compared with HIV-negative patients, HIV-positive patients demonstrated significant elevated intima-media thickness (IMT) (WMD (95% CI) = 0.042 (0.028-0.057)), increased pulse wave velocity (PWV) (0.538 (0.283-0.792)), and reduced flow-mediated vasodilation (FMD) (-2.049 (-2.806 to -1.293)). Elevated IMT was observed in HIV patients receiving ART when compared with those naïve to ART in the 20- to 40-year-old age group (0.078 (0.033-0.123)), the >40-year-old age group (0.038 (0.018-0.057)), and the group comprising >50% males (0.070 (0.041-0.099)). In addition, ART resulted in an increased PWV in HIV patients receiving ART in the group with >50% male proportion (0.628 (0.405-0.851)). HIV patients exposed to PI showed a significant trend toward elevated IMT (0.033 (0.007-0.058)) and increased PWV (0.264 (0.118-0.410)) compared with those without PI exposure.

CONCLUSIONS

The atherosclerotic process was accentuated by elevated IMT, increased PWV, and reduced FMD under condition of HIV infection. Comparison of ART-receiving with ART-naïve patients showed a significant trend toward elevated IMT and increased PWV, especially under treatment with PI-containing drugs.

Endothelial activation and cardiometabolic profiles of treated and never-treated HIV infected Africans

OBJECTIVE

The role the human immunodeficiency virus (HIV) and antiretroviral treatment on endothelial activation, and the subsequent relationship with cardiovascular disease, is not well understood. We investigated endothelial activation, inflammatory and cardiometabolic profiles, and measures of vascular structure and function of 66 antiretroviral treated (ART), 78 never-treated (no-ART) HIV infected and 165 HIV free Africans.

METHODS

Blood samples were obtained for biochemical analysis and blood pressure, pulse wave velocity (PWV) and carotid intima-media thickness (IMT) measurements were performed.

RESULTS

The HIV infection duration was at least five years and the treatment 2.86±0.13 years. The intracellular adhesion molecule (ICAM) and vascular cell adhesion molecule (VCAM) levels were elevated in the HIV infected groups compared to the controls. The odds of higher adhesion molecule levels were increased when HIV infected (especially in the no-ART group); OR no-ART vs. no-HIV: ICAM 3.92 (2.2-7.0); VCAM 16.2 (7.5-35). ICAM and VCAM associated with HIV status and interleukin-6 (IL-6) in the total group (all p<0.01). In both HIV infected groups VCAM associated inversely with CD4 counts (no-ART: β=-0.28, p=0.01; ART: β=-0.22, p=0.07) and TC (no-ART: β=-0.36, p<0.01; ART: β=-0.27, p=0.03). The ART group had an unfavourable lipid profile compared to the no-ART group. The inflammatory markers (C-reactive protein (CRP) and IL-6), PWV and IMT did not differ between the three groups.

CONCLUSION

HIV infected Africans showed endothelial activation when compared to HIV free controls. The endothelial activation was not accompanied by increased inflammation (as measured with CRP and IL-6), arterial stiffness or sub-clinical atherosclerosis.

von Willebrand Factor is elevated in HIV patients with a history of thrombosis

Background: Arterial and venous thrombotic events are more prevalent in HIV infected individuals compared to the general population, even in the era of combination antiretroviral therapy. Although the mechanism is not fully understood, recent evidence suggests a role for chronic immune activation.

Methods: We reviewed the Dutch National HIV registry database for HIV infected patients in Rotterdam with a history of arterial or venous thrombosis and calculated the incidence. We collected samples from patients with and without thrombosis and compared plasma levels of lipopolysaccharide (LPS), LPS binding protein (LBP), soluble CD14 (sCD14), and von Willebrand Factor antigen level (vWF).

Results: During a 10-year period, a total of 60 documented events in 14,026 person years of observation (PYO) occurred, resulting in an incidence rate of 2.50, 2.21, and 4.28 for arterial, venous and combined thrombotic events per 1000 PYO, respectively. The vWF was elevated in the majority of study subjects (mean 2.36 SD ± 0.88 IU/ml); we found a significant difference when comparing venous cases to controls (mean 2.68 SD ± 0.82 IU/ml vs. 2.20 SD ± 0.77 IU/ml; p = 0.024). This difference remained significant for recurrent events (mean 2.78 SD ± 0.75; p = 0.043). sCD14 was positively correlated with LPS (r = 0.255; p = 0.003).

Conclusion: The incidence of venous thrombosis was two-fold higher in HIV infected patients compared to age-adjusted data from general population cohort studies. We couldn't find a clear association between immune activation markers to either arterial or venous thrombotic events. We observed a marked increase in vWF levels as well as a correlation of vWF to first and recurrent venous thrombo-embolic events. These findings suggest that HIV infection is an independent risk factor for coagulation abnormalities and could contribute to the observed high incidence in venous thrombosis. This could be a reason to prolong anti-thrombotic treatment in HIV patients with a history of thrombosis.

A Phase I study to assess the safety, tolerability and pharmacokinetic profile of boceprevir and sildenafil when dosed separately and together, in healthy male volunteers

OBJECTIVES

Boceprevir is a first-generation direct-acting antiviral licensed for the treatment of hepatitis C infection. Sildenafil is an oral therapy for erectile dysfunction. As boceprevir is a potent inhibitor of CYP3A4, potential pharmacokinetic interactions may occur when it is coadministered with sildenafil. The aim of this study was to assess the pharmacokinetic profile of sildenafil and boceprevir when dosed separately and together in healthy volunteers.

METHODS

Thirteen male subjects completed the following study procedures: phase 1 (Day 0), a single dose of 25 mg of sildenafil was administered; washout period (Days 1-9); phase 2 (Days 10-15), 800 mg of boceprevir three times a day was administered; and phase 3 (Day 16), 800 mg of boceprevir and 25 mg of sildenafil were administered. All drugs were administered in the fed state. Intensive pharmacokinetic sampling was undertaken on Days 0, 15 and 16. Differences in the pharmacokinetic parameters of sildenafil, N-desmethyl-sildenafil and boceprevir between phase 3 and the earlier phases were evaluated by changes in the geometric mean ratios (GMRs).

RESULTS

All the drugs were well tolerated with no safety concerns arising. In the presence of boceprevir (phase 3 versus phase 1), the GMR for the plasma Cmax and the AUC24 for sildenafil increased by 1.9-fold (95% CI 1.5-2.4) and 2.7-fold (95% CI 2.1-3.4), respectively, whereas a reduction in the Cmax of N-desmethyl-sildenafil was observed (GMR 0.5, 95% CI 0.4-0.7). No significant changes in boceprevir exposure were observed between phases 3 and 2.

CONCLUSIONS

Exposure of sildenafil is increased in the presence of boceprevir. A dose adjustment of sildenafil is therefore necessary. An initial dose of 25 mg of sildenafil is suggested.

Cardiovascular disease risk in an aging HIV population: not just a question of biology

PURPOSE OF REVIEW

The objective of this review is to appraise recently published literature that describes the relationship between HIV, biologic and environmental risk factors, and cardiovascular disease (CVD) risk with particular emphasis on the aging HIV population and to demonstrate that these biologic and environmental factors may interact to increase the risk of CVD in the HIV population.

RECENT FINDINGS

The mechanisms linking HIV and CVD are multifactorial and encompass biological and 'environmental' modalities including multimorbid conditions that co-occur with HIV, immunologic alterations associated with HIV, polypharmacy (which affects adherence and increases likelihood of adverse drug-drug interactions) and healthcare disparities in CVD risk reduction by HIV status.

SUMMARY

Data regarding optimal treatment strategies that balance immunological restoration and CVD risk reduction are needed.