Use of human immunodeficiency virus-1 protease inhibitors is associated with atherogenic lipoprotein changes and endothelial dysfunction

Exercise to Prevent Accelerated Vascular Aging in People Living With HIV

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

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.

Endothelial dysfunction and cardiovascular diseases in people living with HIV on specific highly active antiretroviral therapy regimen: A systematic review of clinical studies

Despite the improved efficacy of highly active antiretroviral therapy (HAART) in viral suppression, emerging evidence indicates an increased burden of noncommunicable diseases in people living with HIV (PLWH). Immune activation and persistently elevated levels of inflammation have been associated with endothelial dysfunction in PLWH, likely contributing to the development of cardiovascular diseases (CVDs). Here, electronic search databases including PubMed, Google Scholar, Cochrane Library, and Science Direct were used to retrieve scientific evidence reporting on any association between markers of endothelial function and CVD-related outcomes in PLWH on HAART. Extracted data was subjected to quality assessment using the Downs and Black checklist. Most (60 %) of the results indicated the presence of endothelial dysfunction in PLWH on HAART, and this was mainly through reduced flow mediated dilation and elevated serum makers of adhesion molecules like ICAM-1, VCAM-1, and P-selectin. The summarized evidence indicates an association between persistently elevated markers of endothelial dysfunction and a pro-inflammatory state in PLWH on HAART. Only a few studies reported on improved endothelial function markers in PLWH on HAART, while limited evidence is available to prove that endothelial dysfunction is associated with CVD-risk, which could be attributed to therapeutic effects of HAART. Limited studies with relatively high quality of evidence were included in this systematic review. In conclusion, results from this review lay an important foundation for future research, even a meta-analysis, that will improve the understanding of the contributing factors to the burden of CVDs in PLWH on HAART.

Spontaneous bilateral superficial femoral artery pseudoaneurysms and a unilateral posterior tibial artery aneurysm in an immunocompromised patient

Key Clinical Message

The presence of multiple pseudoaneurysms in a patient should prompt investigations for the underlying etiologies including autoimmune and immunosuppressive disease processes. Treatment options include open repair and endovascular stenting.

Abstract

Pseudoaneurysms (also known as false aneurysms) are atypical dilatations or outpouchings from a vessel which are not always contained by the three layers of a normal vessel wall, namely the intima, media, and adventitia. These are distinct from a true aneurysm which has a wall comprising all three layers. The underlying etiology for both true aneurysms and pseudoaneurysm can vary. We present the rare case of bilateral superficial femoral artery pseudoaneurysms, of unknown etiology and a concurrent posterior tibial artery saccular aneurysm in a patient with Human Immunodeficiency Virus (HIV) infection and multiple comorbidities. This was managed using a combination of endovascular covered stent grafts and open surgical repair technique. The patient is doing well on follow-up a year later with no post-operative infections. A literature review of the existing reports of superficial femoral artery pseudoaneurysms and posterior tibial artery aneurysms and their management is also reported.

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 artery endothelial function and aging in people with HIV and HIV-negative individuals

Coronary artery disease (CAD) is a common comorbidity in people with human immunodeficiency virus (HIV) (PWH) and impaired coronary endothelial function (CEF) plays a central role in the pathogenesis of CAD. Age-related impaired CEF among PWH, however, is not well characterized. We investigated the association between CEF and age in males and females with and without HIV using 3-T magnetic resonance imaging (MRI). We measured the changes in coronary cross-sectional area (CSA) and coronary blood flow during isometric handgrip exercise (IHE), an established endothelial-dependent stressor with smaller increases in CSA and coronary blood flow indicative of impaired CEF. We included 106 PWH and 82 individuals without HIV. Differences in demographic and clinical characteristics between PWH and individuals without HIV were explored using Pearson's χ2 test for categorical variables and Welch's t test for continuous variables. Linear regression models were used to examine the association between CEF and age. CEF was significantly lower in PWH as compared with individuals without HIV. Coronary endothelial dysfunction was also present at younger ages in PWH than in the individuals without HIV and there were significant differences in CEF between the PWH and individuals without HIV across age groups. Among the individuals without HIV, the percent changes in CSA were inversely related to age in unadjusted and adjusted models. There was no significant association between CEF and age in PWH. To the best of our knowledge, this is the first study to examine the relationship between age and CEF in PWH, and our results suggest that factors other than age significantly impair CEF in PWH across the life span.NEW & NOTEWORTHY This is the first study to examine the relationship between age and coronary endothelial function (CEF) in people with human immunodeficiency virus (HIV) (PWH). CEF was assessed using magnetic resonance imaging (MRI) in people with and without HIV. Although age and CEF were significantly inversely related in individuals without HIV, there was no association between age and CEF in PWH.

Prevalence and Determinants of Endothelial Dysfunction among Adults Living with HIV in Northwest Nigeria

Background

Endothelial dysfunction constitutes an early pathophysiological event in atherogenesis and cardiovascular disease. This study aimed to assess the prevalence, determinants, and degree of endothelial dysfunction in antiretroviral therapy (ART)-treated people living with HIV (PLWH) in northwestern Nigeria using brachial flow-mediated dilatation (FMD).

Methods

This was a comparative, cross-sectional study. A total of 200 ART-treated adults living with HIV with no evidence of kidney disease were compared with 200 HIV-negative participants attending a tertiary hospital in Kano, Nigeria, between September 2020 and May 2021. Endothelial function was evaluated by measuring FMD with a high-resolution vascular ultrasound transducer. FMD was calculated as the ratio of the brachial artery diameter after reactive hyperemia to baseline diameter and expressed as a percentage of change. Blood and urine samples were obtained from participants in both arms. Urine albumin-to-creatinine ratio (uACR) was calculated using the 2021 CKD-EPI estimated glomerular filtration rate (eGFR) creatinine-cystatin C equation without the race variable, and low-density lipoprotein (LDL) cholesterol was measured using enzymatic method.

Results

The overall mean age (± standard deviation) of the study participants was 42 ± 11 years. Participants in the comparison arm were younger than PLWH (38 ± 11 versus 46 ± 10 years, respectively). The median (interquartile range) uACR was 41.6 (23.2-162.9) mg/g for the ART-treated PLWH versus 14.5 (7.4-27.0) mg/g for healthy controls. PLWH had a significantly lower mean percent FMD when compared to HIV-negative participants (9.8% ± 5.4 versus 12.1% ± 9.2, respectively). Reduced FMD was independently associated with HIV infection (β = -2.83%, 95% CI, -4.44% to -1.21%, p = 0.001), estimated glomerular filtration rate (β = -0.04%, 95% CI, -0.07% to -0.01%, p = 0.004) and LDL cholesterol (β = -1.12%, 95% CI, -2.13% to -0.11%, p = 0.029).

Conclusion

HIV-positive status, lower estimated GFR, and higher LDL cholesterol levels were independently associated with endothelial dysfunction. Future prospective studies with larger cohorts of persons living with HIV (and age- and sex-matched HIV-negative controls) are needed to gain further insight into these important findings. In the interim, aggressive management of modifiable risk factors is warranted.

Posterior reversible encephalopathy syndrome and reversible cerebral vasoconstriction syndrome in patients with COVID-19 infection: is there a link? A systematic review and case report analysis

During the SARS-CoV2 pandemic, several cases of Posterior Reversible Encephalopathy Syndrome (PRES) and of Reversible Cerebral Vasoconstriction Syndrome (RCVS) in COVID-19 patients have been reported, but the link between these syndromes and COVID-19 is unclear. We performed a systematic review, according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement to evaluate whether SARS-CoV2 infection or the drugs used to treat it could be deemed potential risk factors for PRES or RCVS. We performed a literature search. We found 70 articles (60 on PRES and 10 on RCVS) concerning n = 105 patients (n = 85 with PRES, n = 20 with RCVS). We analyzed the clinical characteristics of the two populations separately, then performed an inferential analysis to search for other independent risk factors. We found fewer than usual PRES-related (43.9%) and RCVS-related (45%) risk factors in patients with COVID-19. Such a low incidence of risk factors for PRES and RCVS might suggest the involvement of COVID-19 as an additional risk factor for both diseases due to its capability to cause endothelial dysfunction. We discuss the putative mechanisms of endothelial damage by SARS-CoV2 and antiviral drugs which may underlie the development of PRES and RCVS.

Asthma as a Systemic Disease: Cardiovascular Effects Associated with Asthma

Asthma and cardiovascular disease (CVD) pose significant public health burdens. Airway inflammation is central to asthma pathophysiology and systemic inflammation, which occurs in asthma, is central to CVD pathophysiology. Numerous robust epidemiological studies have demonstrated deleterious systemic cardiovascular effects associated with the asthma syndrome. The cardiovascular effects associated with asthma include arterial injury, atherosclerotic CVD events, atrial fibrillation, and hypertension. Asthma is a heterogeneous disease, however, and the risk of CVD is not homogeneous across the various clinical phenotypes and molecular endotypes, highlighting prior inconsistent associations of asthma and its subtypes with various forms of CVD. The mechanistic underpinnings of the increased CVD risk in asthma remain multifactorial and undefined. Collectively, this supports the need for a precision approach in the identification of individuals with asthma who remain at elevated risk of development of cardiovascular diseases to guide both diagnostic and preventive interventions to decrease CVD risk among individuals living with asthma.

PCSK9 and ANGPTL3 levels correlate with hyperlipidemia in HIV-lipoatrophy, are regulated by fasting and are not affected by leptin administered in physiologic or pharmacologic doses

BACKGROUND

Medications leveraging the leptin, PCSK9, ANGPTL3 and FABP4 pathways are being developed for the treatment of insulin resistance and/or lipid disorders. To evaluate whether these pathways are independent from each other, we assessed the levels of PCSK9, ANGPTL3 and FABP4, in normal subjects and subjects exhibiting HIV and highly active antiretroviral therapy (HAART) induced metabolic syndrome with lipoatrophy and hypoleptinemia. Studies were performed at baseline and during food deprivation for three days with either a placebo or leptin administration at physiological replacement doses to correct fasting induced acute hypoleptinemia and in pharmacological doses.

METHODS

PCSK9, ANGPTL3, FABP4 levels and their correlations to lipoproteins-metabolites were assessed in randomized placebo controlled cross-over studies: a) in 15 normal-weight individuals undergoing three-day admissions in the fed state, in complete fasting with placebo and in complete fasting with leptin treatment in physiologic replacement doses (study 1), b) in 15 individuals day baseline in a fed and three fasting admissions for three days with leptin administered in physiologic, supraphysiologic and pharmacologic doses (study 2), c) in 7 hypoleptinemic men with HIV and HAART-induced lipoatrophy treated with leptin or placebo for two months in the context of a cross over randomized trial (study 3).

RESULTS

Circulating ANGPTL3, PCSK9 and FABP4 were markedly elevated in HIV-lipoatrophy and not affected by leptin treatment. PCSK9 levels correlated with lipids and markers of lipid utilization and lipolysis. ANGPTL3 levels correlated with HDL particles and their lipid composition. FABP4 levels were negatively associated with HDL diameter (HDL-D) and composition. PCSK9 and ANGPTL3 levels decreased during food deprivation by ~65 % and 30 % respectively. Leptin administration at physiologic, supraphysiologic and pharmacologic doses did not affect PCSK9, ANGPTL3 and FABP4 levels.

CONCLUSIONS

PCSK9, ANGPTL3 and FABP4 levels are associated with markers of lipid metabolism and are higher in HIV-lipoatrophy. PCSK9 and ANGPTL3 but not FABP4 decrease in response to food deprivation. PCSK9 and ANGPTL3 regulation is leptin-independent, suggesting independent pathways for lipid regulation. Thus, combining treatments of leptin with PCSK9 and/or ANGPTL3 inhibitors for metabolic diseases should have additive effects and merit further investigation.

CLINICAL TRIAL INFORMATION

ClinicalTrials.gov no. NCT00140231, NCT00140205, NCT00140244.

Immune correlates of cardiovascular co-morbidity in HIV infected participants from South India

BACKGROUND

Understanding the immune correlates of cardiovascular disease (CVD) risk in HIV infection is an important area of investigation in the current era of aging with HIV infection. Less is known about CVD risk and HIV infection in developing nations where additional risk factors may be playing a role in the CVD development. In this study, we assessed the effects of systemic inflammation, microbial translocation (MT), T cell immune activation (IA), and nadir CD4 counts on cardiac function and arterial stiffness as markers of subclinical atherosclerosis in HIV-infected individuals.

METHODS

People with HIV (PWH) who were ART naïve (n = 102) or virally suppressed on ART (n = 172) were stratified on nadir CD4 counts and compared to HIV-uninfected controls (n = 64). Determination was made of cardiac function via radial pulse wave and carotid intima thickness (C-IMT) measurements. Plasma biomarkers of inflammation and MT by ELISA or multiplex assays, and immune activation (IA) of T cells based HLA-DR and CD38 expression were investigated by flow cytometry. T-test, Mann-Whitney U test, and Spearman correlation were used to analyze study parameters.

RESULTS

Reduction in cardiac function with lower cardiac ejection time (p < 0.001), stroke volume (p < 0.001), cardiac output (p = 0.007), higher arterial stiffness (p < 0.05) were identified in ART-naïve participants, compared to PWH on ART (p < 0.05). No significant difference in C-IMT values were noted. Higher inflammatory and MT markers were found in the ART-naïve group compared to treated group who were comparable to uninfected participants, except for having higher TNF-α (p < 0.001) and sCD14 (p < 0.001). Immune activation of CD4 and CD8 T-cells was greater in ART-naïve participants compared to ART-treated and uninfected controls (p < 0.05). Lower nadir CD4 counts, higher inflammation, and higher MT predicted poor cardiac measures in the ART-naïve with nadir CD4 < 200cells/mm³ manifesting the highest arterial stiffness, and lowest cardiac function, whereas ART-treated, even with nadir < 200 cells/mm³ were similar to uninfected in these measures.

CONCLUSIONS

In HIV-infected individuals, initiation of ART even at nadir of < 200 cells/mm³ may prevent or reverse cardiovascular disease outcomes that are easily measurable in low income countries.

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.

Effect of Antiretroviral Therapy on Cardiac Risk Markers in People Living with HIV/AIDS

Introduction:

Chronic HIV infection and antiretroviral therapy (ART) are the major causes of cardiovascular diseases (CVDs) and mortality in HIV patients. This study was conducted to look upon the effect of ART on CVD risk markers in patients on different ART regimens and ART-naïve patients.

Methods:

It was a cross-sectional, observational study done on 120 HIV-infected patients. CV risk markers were assessed and correlated with disease-specific factors within individual subgroups differentiated as Group A (ART naïve), Group B (first-line ART), and Group C (second-line ART). Carotid intimal medial thickness (CIMT) and high-sensitivity C reactive protein (hsCRP) were done to classify cases as having CVD.

Results:

CVD risk parameters were found to be significantly higher in cases on ART, as compared to ART-naïve cases. The mean CIMT among cases in Group C, Group B, and Group A was 0.072 ± 0.01 cm, 0.063 ± 0.01 cm, and 0.055 ± 0.01 cm, respectively (P < 0.01). 95%, 65% and 25% cases in Group C, Group B, and Group A, respectively, had high CIMT (>0.06 cm) and were seen to be directly correlated with disease-related factors, i.e., duration of disease and ART, type of ART, and low CD4 cell counts. hsCRP was significantly increased in 65 out of total 120 cases. The mean hsCRP in Group A, Group B, and Group C was 3.69 ± 3.37, 4.21 ± 3.4, and 5.72 ± 3.54 mg/L, respectively (P < 0.01), which corresponds to the high risk of CVD.

Conclusion:

CVD risk parameters of CIMT and hsCRP are seen to be higher in patients on ART than ART-naive subjects.

Muscle mass, strength, bone mineral density and vascular function in middle-aged people living with HIV vs. age-matched and older controls

Introduction

Combination antiretroviral therapy (cART) substantially extended the life of people living with HIV (PLHIV). However, prolonged HIV infection and cART increase the risk of comorbidities accelerating age-related muscle, bone, and vascular disorders. This cross-sectional study compared muscle mass and strength, bone mineral density (BMD), and vascular function in middle-aged PLHIV treated with cART vs. non-infected age-matched and older controls.

Methods

After careful screening for secondary diseases and medications, body composition, muscular and vascular function were assessed in 12 PLHIV (43.9±8.7 yrs old; HIV-infection for 16.2±8.6 yrs; on cART for 11.6±9.2 yrs), 12 age-matched (CONT, 43.2±8.5 yrs old), and 12 older (OLDER, 74.4±8.3 yrs old) controls through dual x-ray absorptiometry, isokinetic dynamometry, and venous occlusion plethysmography, respectively.

Results

PLHIV and CONT showed similar relative muscle mass (65.3±8.0 vs. 66.9±7.3%, respectively; P= 0.88) and strength (160.7±53.9 vs. 152.0±52.9 N.m⁻¹, respectively; P= 0.90), which were greater than OLDER (80.6±18.8 N.m^−1; P= 0.001). Total BMD was similar in PLHIV (1.04±0.13 g.cm⁻²) and OLDER (1.00±0.15 g.cm⁻², P= 0.86), and both groups presented lower values than CONT (1.20±0.13 g.cm⁻², P< 0.01). No significant difference across groups was detected for macrovascular reactivity (P= 0.32).

Conclusion

Age-related osteopenia might be accelerated in middle-aged PLHIV on prolonged cART, as their BMD approached values found in older adults. On the other hand, muscle mass, isokinetic strength, and vasodilation capacity were similar in PLHIV and age-matched uninfected controls.

Cardiovascular risks associated with protease inhibitors for the treatment of HIV

Introduction: Cumulative use of some first-generation protease inhibitors has been associated with higher rates of dyslipidemia and increased risk of cardiovascular disease. The protease inhibitors most commonly in use are atazanavir and darunavir, which have fewer detrimental lipid effects and greater tolerability. This paper aims to review the evidence of a potential association of these contemporary protease inhibitors with the risk of ischemic CVD and atherosclerotic markers.Areas covered: We searched for publications of randomized trials and observational studies on PubMed from 1 January 2000 onwards, using search terms including: protease inhibitors; darunavir; atazanavir; cardiovascular disease; cardiovascular events; dyslipidemia; mortality; carotid intima media thickness; arterial elasticity; arterial stiffness and drug discontinuation. Ongoing studies registered on clinicaltrials.gov as well as conference abstracts from major HIV conferences from 2015-2020 were also searched.Expert opinion: Atazanavir and darunavir are no longer part of first-line HIV treatment, but continue to be recommended as alternative first line, second- and third-line regimens, as part of two drug regimens, and darunavir is used as salvage therapy. Although these drugs will likely remain in use globally for several years to come, baseline CVD risk should be considered when considering their use, especially as the population with HIV ages.

Role of Brain Arterial Remodeling in HIV-Associated Cerebrovascular Outcomes

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

Non-linear optical imaging of atherosclerotic plaques in the context of SIV and HIV infection prominently detects crystalline cholesterol esters

Chronic HIV infection may exacerbate atherosclerotic vascular disease, which at advanced stages presents as necrotic plaques rich in crystalline cholesterol. Such lesions can catastrophically rupture precipitating myocardial infarct and stroke, now important causes of mortality in those living with HIV. However, in this population little is known about plaque structure relative to crystalline content and its chemical composition. Here, we first interrogated plaque crystal structure and composition in atherosclerotic SIV-infected macaques using non-linear optical microscopy. By stimulated Raman scattering and second harmonic generation approaches both amorphous and crystalline plaque lipid was detected and the crystal spectral profile indicated a cholesterol ester (CE) dominated composition. Versus controls, SIV⁺ samples had a greater number of cholesterol crystals (CCs), with the difference, in part, accounted for by crystals of a smaller length. Given the ester finding, we profiled HIV⁺ plaques and also observed a CE crystalline spectral signature. We further profiled plaques from Ldlr^-/- mice fed a high fat diet, and likewise, found CE-dominate crystals. Finally, macrophage exposure to CCs or AcLDL induced auto-fluorescent puncta that co-stained with the LC3B autophagy sensor. In aggregate, we show that atheromatous plaques from mice, macaques and humans, display necrotic cores dominated by esterified CCs, and that plaque macrophages may induce autophagic vesicle formation upon encountering CCs. These findings help inform our knowledge of plaque core lipid evolution and how the process may incite systemic inflammation.

Endothelial Dysfunction in South African Youth Living With Perinatally Acquired Human Immunodeficiency Virus on Antiretroviral Therapy

BACKGROUND

Human immunodeficiency virus (HIV) and antiretroviral therapy (ART) confer cardiovascular disease (CVD) risk in adults with HIV. Few studies have assessed endothelial dysfunction (ED), an early marker of subclinical CVD risk, in youth living with perinatally acquired HIV (YLPHIV).

METHODS

Using peripheral arterial tonometry, we compared ED in YLPHIV and age-matched youth without HIV. A reactive hyperemic index ≤1.35 was defined as ED. Eligible participants included those aged 9-14 years and on ART ≥6 months at enrollment.

RESULTS

Overall, 431 YLPHIV and 93 youth without HIV with a median age of 14.1 versus 13.9 years, respectively, were included. YLPHIV had a lower BMI z score (BMIZ; -0.2 vs 0.4; P < .01) but higher rates of hypercholesterolemia (10% vs 1%; P = .01) than youth without HIV. Among YLPHIV, mean log viral load (VL) was 4.83 copies/mL with 21.7% having a CD4 count <500 cell/mm3; median duration on ART was 9.8 years with 38% initiating at <2 years of age. YLPHIV had higher rates of ED than youth without HIV (50% vs 34%; P = .01); this relationship persisted after adjusting for age, sex, BMIZ, elevated BP, and hypercholesterolemia (RR, 1.43; P = .02). Among YLPHIV, CD4 count >500 cell/mm3 (RR, 1.04; P = .76), VL (RR, 1.01; P = .78), and current ART class (protease inhibitor based vs nonnucleoside inhibitor based: relative risk, 0.90; P = .186) were not associated with ED after adjustment.

CONCLUSIONS

Even after adjusting for physiologic differences, YLPHIV appear to be at increased risk of ED compared with age-matched youth without HIV. These findings have important implications for the life course of YLPHIV who may be at increased risk of premature CVD and complications.

HIV Protease Inhibitor Ritonavir Impairs Endothelial Function Via Reduction in Adipose Mass and Endothelial Leptin Receptor-Dependent Increases in NADPH Oxidase 1 (Nox1), C-C Chemokine Receptor Type 5 (CCR5), and Inflammation

Background Cardiovascular disease is currently the leading cause of death in patients with human immunodeficiency virus on combination antiretroviral therapy. Although the use of the protease inhibitor ritonavir has been associated with increased prevalence of cardiovascular disease, the underlying mechanisms remain ill-defined. Herein, we tested the hypothesis that ritonavir-mediated lipoatrophy causes endothelial dysfunction via reducing endothelial leptin signaling. Methods and Results Long-term (4 weeks) but not short-term (3 days) treatment with ritonavir reduced body weight, fat mass, and leptin levels and induced endothelial dysfunction in mice. Moreover, ritonavir increased vascular NADPH oxidase 1, aortic H₂O₂ levels as well as interleukin-1β, GATA3 (GATA binding protein 3), the macrophage marker (F4/80), and C-C chemokine receptor type 5 (CCR5) expression. Reactive oxygen species scavenging with tempol restored endothelial function, and both NADPH oxidase 1 and CCR5 deletion in mice protected from ritonavir-mediated endothelial dysfunction and vascular inflammation. Remarkably, leptin infusion markedly improved endothelial function and significantly reduced vascular NADPH oxidase 1, interleukin-1β, GATA3, F4/80, and CCR5 levels in ritonavir-treated animals. Selective deficiency in endothelial leptin receptor abolished the protective effects of leptin infusion on endothelial function. Conversely, selective increases in endothelial leptin signaling with protein tyrosine phosphatase deletion blunted ritonavir-induced endothelial dysfunction. Conclusions All together, these data indicate that ritonavir-associated endothelial dysfunction is a direct consequence of a reduction in adiposity and leptin secretion, which decreases endothelial leptin signaling and leads to a NADPH oxidase 1-induced, CCR5-mediated reduction in NO bioavailability. These latter data also introduce leptin deficiency as an additional contributor to cardiovascular disease and leptin as a negative regulator of CCR5 expression, which may provide beneficial avenues for limiting human immunodeficiency virus infection.

Elevated Eosinophils as a Feature of Inflammation Associated With Hypertension in Virally Suppressed People Living With HIV

Background

People living with HIV (PLWH) are at increased risk of cardiovascular disease, including hypertension, which persists despite effective plasma viral suppression on antiretroviral therapy. HIV infection is characterized by long‐term alterations in immune function, but the contribution of immune factors to hypertension in PLWH is not fully understood. Prior studies have found that both innate and adaptive immune cell activation contributes to hypertension.

Methods and Results

We hypothesized that chronic inflammation may contribute to hypertension in PLWH. To test this hypothesis, we enrolled a cohort of 70 PLWH (44% hypertensive) on a long‐term single antiretroviral therapy regimen for broad phenotyping of inflammation biomarkers. We found that hypertensive PLWH had higher levels of inflammatory cytokines, including tumor necrosis factor‐α receptor 1, interleukin‐6, interleukin‐17, interleukin‐5, intercellular adhesion molecule 1 and macrophage inflammatory protein‐1α. After adjustment for age, sex, and fat mass index, the circulating eosinophils remained significantly associated with hypertension. On the basis of these results, we assessed the relationship of eosinophils and hypertension in 2 cohorts of 50 and 81 039 similar HIV‐negative people; although eosinophil count was associated with prevalent hypertension, this relationship was abrogated by body mass index.

Conclusions

These findings may represent a unique linkage between immune status and cardiovascular physiological characteristics in HIV infection, which should be evaluated further.

Recent advances in understanding lipodystrophy: a focus on lipodystrophy-associated cardiovascular disease and potential effects of leptin therapy on cardiovascular function

Lipodystrophy is a disease characterized by a partial or total absence of adipose tissue leading to severe metabolic derangements including marked insulin resistance, type 2 diabetes, hypertriglyceridemia, and steatohepatitis. Lipodystrophy is also a source of major cardiovascular disorders which, in addition to hepatic failure and infection, contribute to a significant reduction in life expectancy. Metreleptin, the synthetic analog of the adipocyte-derived hormone leptin and current therapy of choice for patients with lipodystrophy, successfully improves metabolic function. However, while leptin has been associated with hypertension, vascular diseases, and inflammation in the context of obesity, it remains unknown whether its daily administration could further impair cardiovascular function in patients with lipodystrophy. The goal of this short review is to describe the cardiovascular phenotype of patients with lipodystrophy, speculate on the etiology of the disorders, and discuss how the use of murine models of lipodystrophy could be beneficial to address the question of the contribution of leptin to lipodystrophy-associated cardiovascular disease.

Antiretroviral drug-induced endothelial dysfunction is improved by dual PPARα/γ stimulation in obesity

Obesity rates are rising in HIV-infected populations; however, the putative role of highly active antiretroviral therapy (HAART) in the development of endothelial and cardiovascular derangements in the presence of pre-existing overweight/obesity is unclear. Although dual peroxisome proliferator-activated receptors-alpha/gamma (PPARα/γ) stimulation mitigates HAART-induced metabolic dysfunction, vascular effects are unresolved. To investigate whether HAART induces vascular dysfunction in obesity and to explore the underlying mechanisms of PPARα/γ stimulation, male Wistar rats were placed on a high-calorie diet for 16 weeks. After 10 weeks, HAART (lopinavir/ritonavir, azidothymidine/lamivudine) with/without PPARα/γ agonist, Saroglitazar, was administered daily for six weeks. Excised thoracic aorta rings were subjected to isometric tension studies and Western blot measurements. HAART+Saroglitazar-treated obese animals recorded lower adiposity indices (4.3 ± 0.5%) vs. HAART only-treated obese rats (5.6 ± 0.3%; p < .01). Maximum acetylcholine-induced vasorelaxation (R_max), was lower in obese+HAART group (76.10 ± 3.58%) vs. obese control (101.40 ± 4.75%; p < .01). However, R_max was improved in obese+ HAART+Saroglitazar (101.00 ± 3.12%) vs. obese+HAART rats (p < .001). The mean LogEC₅₀ was improved in obese+HAART+Saroglitazar vs. obese+HAART group; p = .003. Improved endothelial function in obese+ HAART+Saroglitazar group was associated with upregulation of eNOS, PKB/Akt and downregulated p22-phox expression vs. obese+HAART group. Therefore, PPARα/γ stimulation attenuated HAART-induced endothelial dysfunction by upregulating vasoprotective eNOS, PKB/Akt signaling and downregulating pro-oxidative p22-phox expression.

In-vivo MRI Reveals Changes to Intracerebral Vasculature Caliber in HIV Infection

Objective: To characterize cerebral arterial remodeling in HIV-infected (HIV+) individuals in-vivo, and to study its clinical and immunological associations.

Methods: T2^*-weighted magnetic resonance imagining sequences was used to determine cross-sectional area (vascular caliber) of the anterior (A1 segment) and middle (M1 segment) cerebral arteries in HIV- (control) and HIV+ subjects on antiretroviral therapy. Correlations of A1 caliber with clinical, demographic parameters, and immunological markers in cerebrospinal fluid (CSF) were determined using multivariable analyses.

Results: A1 and M1 calibers from 22 HIV- control subjects (age: median 48.5 years, range 22-60 years, 55% male) and 61 HIV+ subjects (age: median 53 years, range 25–60 years, 67% male) were studied. ANCOVA, adjusting for ethnicity and sex (age was not correlated with M1 or A1 caliber in either group), revealed that HIV+ subjects had larger caliber in the A1 segment than HIV- subjects (4.95 ± 0.14 mm², and 4.47 ± 0.21 mm² respectively, p = 0.048), but caliber of the M1 segment did not differ among the groups (7.21 ± 0.14 mm² and 7.09 ± 0.23 mm² respectively, p = 0.65). In the HIV+ cohort, longer disease duration and higher current CD4 T-cell count were associated with reduced A1 caliber (r =−0.42 and −0.33 respectively, p < 0.05). In addition, increase in cardiovascular disease risk (CVD risk) was associated with a decrease in A1 caliber in the HIV group (r = −0.35, p < 0.05).

Conclusions: This cross-sectional study reveals an increase in A1 caliber in the HIV+ cohort, compared to control subjects, which is especially prominent in early phase of the disease. This increase in caliber may be associated with acute pathological processes in HIV during the initial stages of infection resulting in loss of compliance or thinning of the arterial wall. At later stages, such changes may be confounded by arteriosclerotic changes that are common in later stages of HIV infection. This study suggests there is extensive vessel remodeling in various stages of infection. Long-term longitudinal follow-up of this cohort is planned to further verify this hypothesis and to better understand this MRI marker of intracranial vascular caliber.

Cocaine use modifies the association between antiretroviral therapy and endothelial dysfunction among adults with HIV infection

Cocaine is commonly used among HIV-infected people and may worsen HIV disease progression. In addition, existing evidence suggests a link between antiretroviral regimens and endothelial dysfunction. This study aimed to examine whether the associations of antiretroviral therapy (ART) regimens with endothelial dysfunction may be modified by cocaine use in adults with HIV infection. Between 2003 and 2014, 466 HIV-positive participants residing in Baltimore, Maryland, were enrolled in a study investigating comorbidities associated with HIV/ART. The associations between various risk factors and endothelial dysfunction indicators were examined by robust regression models fitted for the overall subjects and cocaine subgroups, separately. Duration of nonnucleoside reverse-transcriptase inhibitor (NNRTI)-based therapy was negatively associated with plasma vWF:Ag levels in cocaine non-users (β = -.715, SE = .220, P < .05). However, cocaine users on longer-term NNRTI-based regimens had greater plasma endothelin-1 (ET-1) concentrations than their counterparts (β = .003, SE = .001, P < .05). In addition, current cigarette smoking was significantly positively associated with ET-1 concentrations in both cocaine non-users (β = .609, SE = .164, P < .05) and cocaine users (β = .331, SE = .086, P < .05). In conclusion, cocaine use modified the potential effects of NNRTI-based therapy on biomarkers of endothelial dysfunction. These findings suggested that reduction in cocaine use may improve endothelial function in HIV-infected cocaine users.

HIV disease, metabolic dysfunction and atherosclerosis: A three year prospective study

HIV infection is known to be associated with cardiometabolic abnormalities; here we investigated the progression and causes of these abnormalities. Three groups of participants were recruited: HIV-negative subjects and two groups of treatment-naïve HIV-positive subjects, one group initiating antiretroviral treatment, the other remaining untreated. Intima-media thickness (cIMT) increased in HIV-positive untreated group compared to HIV-negative group, but treatment mitigated the difference. We found no increase in diabetes-related metabolic markers or in the level of inflammation in any of the groups. Total cholesterol, low density lipoprotein cholesterol and apoB levels were lower in HIV-positive groups, while triglyceride and Lp(a) levels did not differ between the groups. We found a statistically significant negative association between viral load and plasma levels of total cholesterol, LDL cholesterol, HDL cholesterol, apoA-I and apoB. HIV-positive patients had hypoalphalipoproteinemia at baseline, and we found a redistribution of sub-populations of high density lipoprotein (HDL) particles with increased proportion of smaller HDL in HIV-positive untreated patients, which may result from increased levels of plasma cholesteryl ester transfer protein in this group. HDL functionality declined in the HIV-negative and HIV-positive untreated groups, but not in HIV-positive treated group. We also found differences between HIV-positive and negative groups in plasma abundance of several microRNAs involved in lipid metabolism. Our data support a hypothesis that cardiometabolic abnormalities in HIV infection are caused by HIV and that antiretroviral treatment itself does not influence key cardiometabolic parameters, but mitigates those affected by HIV.

The effect of switching protease inhibitors to raltegravir on endothelial function, in HIV-infected patients

Objective Lipid management is one of the cornerstones of cardiovascular risk reduction. Treatment of HIV infection with protease inhibitors (PIs) may cause dyslipidaemia, whilst the integrase inhibitor raltegravir (RAL) has a relatively favorable effect on plasma lipids. We examined the effect of switching from PIs to RAL on endothelial function, and its effect on immunological and inflammatory parameters. Methods We performed a 16-week open-label prospective crossover study: 8 weeks intervention (switch PIs to RAL) and 8 weeks control (unchanged cART regimen). Flow-mediated dilatation (FMD), inflammatory plasma, and cellular markers of immune activation were measured at weeks 0, 8, and 16. Results Study participants (n = 22) with a median age of 50 years (IQR 42-60) and known HIV infection of 6.5 years (IQR 5.0-17.3) were on stable cART with undetectable HIV viral loads. After 8 weeks of RAL therapy, a reduction in FMD of -0.81% was seen, compared to +0.54% control (pairwise, p = 0.051), while fasting total cholesterol (-17% versus +10%; p < 0.001), LDL cholesterol (-21% versus -3%; p = 0.026), and triglycerides (-41% versus +18%; p = 0.001) significantly decreased during RAL therapy compared to the control. Furthermore, a relation between the change in percentage of B-1 cells and the change in FMD was found (β 0.40, 95%CI 0.16; 0.64, p = 0.005) during treatment with RAL. Finally, during RAL therapy, 27% of the patients experienced an increased ALT rise. Conclusions We present an overall negative study, where switching from PIs to RAL slightly reduced the endothelial function while decreasing plasma lipids, thus possibly decreasing the CVD risk in the long term. A transient elevation of ALT was seen upon switch to RAL.

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.

The HIV protease inhibitor, ritonavir, dysregulates human platelet function in vitro

There are 37 million people globally infected with the Human Immunodeficiency Virus (HIV). People living with HIV can achieve nearly normal lifespans due to the use of antiretroviral drugs (ARVs). However, people living with HIV experience chronic inflammation and increased risk for cardiovascular diseases (CVD) relative to uninfected people. While the cause for this risk is unclear, some ARVs have been associated with CVD, and it is speculated that some ARVs potentiate inflammation in infected individuals. Platelets are a critical link between inflammation and the development and progression of CVD, but the effects of ARVs on platelets are largely understudied. In this study, we examined the effects of ARVs on human platelet function in vitro. Our data show that the ARV ritonavir, a protease inhibitor, severely altered human platelet lipid mediator production (prostaglandin E2 and thromboxane) in both resting and activated platelets. Further characterization revealed that ritonavir altered measures of platelet hemostatic and thrombotic function that included significantly decreased platelet spreading, increased platelet aggregation, and trended toward increased clot strength. These data provide proof-of-principle that ARVs can directly dysregulate human platelets, possibly contributing to inflammation-related comorbidities. These data may provide mechanistic insight into the factors contributing to increased risk of CVD in people living with HIV, and may help guide future development of new HIV agents and ARV regimens that mitigate platelet dysregulation by ARVs.

Posterior reversible encephalopathy syndrome in a patient with HIV/AIDS and immune reconstitution syndrome: a case study and literature review

The etiology of posterior reversible encephalopathy (PRES) is typically multifactorial. Patients with HIV are at risk for the development of this syndrome. We review 17 published cases of HIV and PRES and describe the second reported case of PRES in the setting of HIV and immune reconstitution syndrome (IRIS). IRIS has not yet been described as a risk factor for PRES.

Lipodystrophy diagnosis in people living with HIV/AIDS: prediction and validation of sex-specific anthropometric models

BACKGROUND

Body composition alterations, or lipodystrophy, can lead to serious health problems in people living with HIV/AIDS (PLWHA). The objectives of this study are to predict and validate sex-specific anthropometric predictive models for the diagnosis of lipodystrophy in PLWHA.

METHODS

A cross-sectional design was employed to recruit 106 PLWHA (men = 65 and women = 41) in Brazil during 2013-2014. They were evaluated using dual-energy X-ray absorptiometry, and 19 regions of body perimeters and 6 skinfold thicknesses were taken. Sex-specific predictive models for lipodystrophy diagnosis were developed through stepwise linear regression analysis. Cross-validations using predicted residual error sum of squares was performed to validate each predictive model.

RESULTS

Results support the use of anthropometry for the diagnosis of lipodystrophy in men and women living with HIV/AIDS. A high power of determination with a small degree of error was observed for lipodystrophy diagnosis for men in model six (r² = 0.77, SEE = 0.14, r²_PRESS = 0.73, SEE _PRESS = 0.15), that included ratio of skinfold thickness of subscapular to medial calf, skinfold thickness of thigh, body circumference of waist, formal education _years, time of diagnosis to HIV _months, and type of combined antiretroviral therapy (cART) (with protease inhibitor "WI/PI = 1" or without protease inhibitor "WO/PI = 0"); and model five for women (r² = 0.78, SEE = 0.11, r²_PRESS = 0.71, SEE _PRESS = 0.12), that included skinfold thickness of thigh, skinfold thickness of subscapular, time of exposure to cART _months, body circumference of chest, and race _(Asian) ("Yes" for Asian race = 1; "No" = 0).

CONCLUSIONS

The proposed anthropometric models advance the field of public health by facilitating early diagnosis and better management of lipodystrophy, a serious adverse health effect experienced by PLWHA.

Cardiovascular disease and use of contemporary protease inhibitors: the D:A:D international prospective multicohort study

BACKGROUND

Although earlier protease inhibitors have been associated with increased risk of cardiovascular disease, whether this increased risk also applies to more contemporary protease inhibitors is unknown. We aimed to assess whether cumulative use of ritonavir-boosted atazanavir and ritonavir-boosted darunavir were associated with increased incidence of cardiovascular disease in people living with HIV.

METHODS

The prospective Data Collection on Adverse Events of Anti-HIV Drugs (D:A:D) study consists of people living with HIV-1 from 11 cohorts in Australia, Europe, and the USA. Participants were monitored from Jan 1, 2009, until the earliest of a cardiovascular event, 6 months after the last visit, or until Feb 1, 2016. The outcome of interest was the incidence of cardiovascular disease in adults (aged ≥16 years) living with HIV who were being treated with contemporary treatments. We defined cardiovascular disease as centrally validated myocardial infarction, stroke, sudden cardiac death, or use of invasive cardiovascular procedures, including coronary bypass, coronary angioplasty, and carotid endarterectomy. We used Poisson regression models to assess the associations between cardiovascular disease and the contempoary protease inhibitors atazanavir and darunavir (both boosted with ritonavir).

FINDINGS

49 709 participants were enrolled in the original cohort from 1999 onwards; 35 711 (71·8%) participants with available data on CD4 cell count and viral load at the 2009 baseline were included in the current analysis, and 13 998 (28·2%) participants had insufficent follow-up data after 2009. During a median 6·96 years of follow-up (IQR 6·28-7·08), 1157 people developed cardiovascular disease (incidence rate 5·34 events per 1000 person-years; 95% CI 5·03-5·65). The incidence rate of cardiovascular disease progressively increased from 4·91 events per 1000 person-years (4·59-5·23) in individuals unexposed to ritonavir-boosted darunavir to 13·67 events per 1000 person-years (8·51-18·82) in those exposed to the drug for more than 6 years. The changes associated with ritonavir-boosted atazanavir were less pronounced, showing an incidence rate of 5·03 cardiovascular events per 1000 person-years (4·69-5·37) in unexposed individuals to 6·68 events per 1000 person-years (5·02-8·35) in participants exposed for more than 6 years. After adjustment, keeping factors on the potential causal pathway from boosted protease inhibitor use to cardiovascular disease fixed at baseline, ritonavir-boosted darunavir use was associated with increased risk of cardiovascular disease (incidence rate ratio 1·59; 95% CI 1·33-1·91 per 5 years additional use), but use of ritonavir-boosted atazanavir was not (1·03; 0·90-1·18). This association remained after adjustment for time-updated factors on the potential causal pathway; myocardial infarction and stroke separately; plasma bilirubin concentration; and after stratification by use of ritonavir-boosted darunavir as the first ever protease inhibitor, used in combination with a non-nucleoside reverse transcriptase inhibitor, by previous virological failure, and by those at high risk of cardiovascular disease.

INTERPRETATION

Cumulative use of ritonavir-boosted darunavir, but not of ritonavir-boosted atazanavir, is associated with progressively increasing risk of cardiovascular disease. Causal inference is limited by the observational nature of the D:A:D study. Our findings should prompt investigation into the possible underlying mechanisms of this finding.

FUNDING

The Highly Active Antiretroviral Therapy Oversight Committee.

Short-term folinic acid supplementation and aerobic exercise improve vascular reactivity in HIV-infected individuals

The aim of this study was to determine the effect of supervised exercise and folinic acid supplementation on endothelial function in HIV-infected individuals. A randomized clinical trial, double blinded, was conducted with 16 HIV-infected individuals, antiretroviral therapy (at least 6 months) with undetectable viral load (<50 copies/mL), and CD4 count > 200 cells/mm³. The subjects were randomized to aerobic exercise (n = 5) and daily intake for 4 weeks of 5 mg of folinic acid (n = 6) or placebo (n = 5) groups. To assess endothelial function, venous occlusion plethysmography in the brachial artery by the protocol of reactive hyperemia was performed. The aerobic protocol consisted in cycling exercise, 3 times/week at 60-80% VO₂max, for 4 weeks. Exercise group (Δ6.5 mL/min/100 mL) and folinic acid group (Δ7.3 mL/min/100 mL) improved reactive hyperemia, but no difference was found in placebo group (from Δ -0.3 ml/min/100 ml, time p < 0.001, interaction p = 0.02). Results demonstrate that supervised exercise and folinic acid supplementation in very short term improve endothelial function in HIV-infected individuals. As exercise and folate supplementation are safe and relatively inexpensive, this finding deserves more attention in large randomized clinical trials in an attempt to reduce cardiovascular risk in HIV-infected population.

Carotid intima-media thickness, flow-mediated dilatation and proteinuria in patients of human immunodeficiency virus-positive patients: A case-control study

Introduction

Endothelium-dysfunction (ED) is a surrogate marker of coronary atherosclerotic disease. Carotid intima-media thickness (CIMT), flow-mediated dilatation (FMD), and proteinuria are surrogate markers of ED. Few studies have shown that patients with HIV have impaired endothelial function and are thus at risk of accelerated atherosclerosis.

Materials and Methods

The present study assessed ED in HIV patients by various biophysical parameters as brachial artery FMD, CIMT, and proteinuria. A total of 43 HIV-infected patients were compared with 25 healthy controls who were healthy.

Results

Mean age of patients with HIV was 33.84 ± 5.61 years while that of healthy controls was 31.48 ± 5.40 years. Male to female ratio among cases was 24:19 while among controls was 17:8. Mean CIMT was significantly higher among cases than control (0.513 ± 0.079, 0.452 ± 0.050 mm, respectively, P = 0.001). Percentage change in FMD was significantly lower among cases than control (3.27 ± 2.01, 6.96 ± 1.28, respectively, P = 0.001). Urine protein grading was significantly different between cases and controls (P = 0.007), with stable HIV cases having significantly higher urine protein grading compared to healthy controls. However, no correlation was seen between CIMT, FMD, and proteinuria overall among cases and controls.

Conclusions

HIV-infected patients have significant impairment of endothelial function, in the form of increased CIMT, impaired FMD, and more proteinuria as compared to healthy controls.

HIV-positive youth who are perinatally infected have impaired endothelial function

OBJECTIVE

Evaluating cardiovascular disease risk in children and youth 13 to 24 years old who are facing a life time exposure to both HIV and antiretroviral therapy is a research priority. This study compares endothelial function measured by peripheral arterial tonometry in HIV-positive youth infected perinatally and behaviorally as well as HIV-negative controls.

METHODS

Three groups of participants aged 8-30 year were enrolled; HIV-positive perinatally infected, HIV-positive behaviorally infected on antiretroviral therapy with HIV-1 RNA less than 1000 copies/ml, and HIV-negative controls. We measured the reactive hyperemic index, a measure of endothelial function, using endoPAT (Caesarea, Israel). Markers of systemic inflammation, monocyte activation, and gut integrity were also assessed. Spearman correlations and regression analyses were used to explore relationships between endothelial function measures and other measured variables.

RESULTS

Overall, 119 participants were enrolled: 53 HIV-positive behaviorally infected, 18 HIV-positive perinatally infected, and 48 controls. Overall, 71% were men; 77% African Americans and median age was 22 years old. Median (interquartile range) reactive hyperemic index was lower in the HIV-positive perinatally infected group [1.34 (1.20, 1.42)], compared with the behaviorally infected group [1.52 (1.34, 1.75)] and the control group [1.52 (1.27, 1.80; P < 0.01)]. Soluble CD14, a marker of monocyte activation, intestinal fatty acid-binding protein, a marker of gut integrity and soluble vascular cell adhesion molecule, a marker of vascular dysfunction, were different among the three groups (P ≤ 0.01).

CONCLUSION

HIV-positive youth infected perinatally appear to have higher levels of endothelial dysfunction and immune activation when compared with behaviorally infected youth. Further longitudinal studies are needed to determine whether perinatally infected youth have higher risks of cardiovascular disease.

Relationship Between HIV Infection, Antiretroviral Therapy, Inflammatory Markers, and Cerebrovascular Endothelial Function Among Adults in Urban China

BACKGROUND

Cerebrovascular risk is increased in people living with HIV infection compared with age-matched uninfected individuals. Cerebrovascular endothelial dysfunction related to antiretroviral therapy (ART) and inflammation may contribute to higher stroke risk in HIV infection.

METHODS

We compared cerebral vasoreactivity-a measure of cerebrovascular endothelial function assessed by the breath-holding index (BHI) using transcranial Doppler ultrasound-between virologically suppressed Chinese HIV-infected individuals followed in an HIV clinic in Beijing, China, and uninfected controls. We constructed mixed-effects models to evaluate the association of HIV, ART, and inflammatory markers with cerebral vasoreactivity.

RESULTS

In an unadjusted model, HIV infection was associated with a trend toward lower cerebral vasoreactivity (BHI 1.08 versus 1.26, P = 0.079). In multivariable analyses, cholesterol modified the association between HIV infection and cerebral vasoreactivity (P = 0.015 for interaction). At a lower total cholesterol of 4.15 mmol/L, HIV was associated with lower cerebral vasoreactivity (BHI -0.28, P = 0.019), whereas at a cholesterol of 5.15 mmol/L, the reduction in cerebral vasoreactivity associated with HIV was no longer statistically significant (BHI -0.05, P = 0.64). Among HIV-infected individuals, use of lopinavir/ritonavir compared with efavirenz was associated with lower cerebral vasoreactivity (BHI -0.24, P = 0.040). We did not find a significant association between inflammatory markers and cerebral vasoreactivity.

CONCLUSIONS

Cerebrovascular endothelial dysfunction associated with HIV infection may be most relevant for individuals with less traditional vascular risk, such as those with lower cholesterol. Further study of the impact of ART on cerebrovascular endothelial function is warranted to aid with ART selection in individuals at high cerebrovascular risk.

Changes in Cardiovascular Disease Risk Factors With Immediate Versus Deferred Antiretroviral Therapy Initiation Among HIV-Positive Participants in the START (Strategic Timing of Antiretroviral Treatment) Trial

INTRODUCTION

HIV infection and certain antiretroviral therapy (ART) medications increase atherosclerotic cardiovascular disease risk, mediated, in part, through traditional cardiovascular disease risk factors.

METHODS AND RESULTS

We studied cardiovascular disease risk factor changes in the START (Strategic Timing of Antiretroviral Treatment) trial, a randomized study of immediate versus deferred ART initiation among HIV-positive persons with CD4⁺ cell counts >500 cells/mm³. Mean change from baseline in risk factors and the incidence of comorbid conditions were compared between groups. The characteristics among 4685 HIV-positive START trial participants include a median age of 36 years, a CD4 cell count of 651 cells/mm³, an HIV viral load of 12 759 copies/mL, a current smoking status of 32%, a median systolic/diastolic blood pressure of 120/76 mm Hg, and median levels of total cholesterol of 168 mg/dL, low-density lipoprotein cholesterol of 102 mg/dL, and high-density lipoprotein cholesterol of 41 mg/dL. Mean follow-up was 3.0 years. The immediate and deferred ART groups spent 94% and 28% of follow-up time taking ART, respectively. Compared with patients in the deferral group, patients in the immediate ART group had increased total cholesterol and low-density lipoprotein cholesterol and higher use of lipid-lowering therapy (1.2%; 95% CI, 0.1-2.2). Concurrent increases in high-density lipoprotein cholesterol with immediate ART resulted in a 0.1 lower total cholesterol to high-density lipoprotein cholesterol ratio (95% CI, 0.1-0.2). Immediate ART resulted in 2.3% less BP-lowering therapy use (95% CI, 0.9-3.6), but there were no differences in new-onset hypertension or diabetes mellitus.

CONCLUSIONS

Among HIV-positive persons with preserved immunity, immediate ART led to increases in total cholesterol and low-density lipoprotein cholesterol but also concurrent increases in high-density lipoprotein cholesterol and decreased use of blood pressure medications. These opposing effects suggest that, in the short term, the net effect of early ART on traditional cardiovascular disease risk factors may be clinically insignificant."

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT00867048.

Cardiovascular risk in advanced naïve HIV-infected patients starting antiretroviral therapy: Comparison of three different regimens - PREVALEAT II cohort

BACKGROUND AND AIMS

PREVALEAT (PREmature VAscular LEsions and Antiretroviral Therapy) II is a multicenter, longitudinal cohort study aimed at the evaluation of cardiovascular risk among advanced HIV-positive, treatment-naïve patients starting their first therapy. We hypothesized that these patients, present a higher cardiovascular (CV) risk.

METHODS

The study included all consecutive naïve patients with less than 200 CD4 cells/ml starting antiretroviral therapy. Our primary objective was to evaluate changes in carotid intima- media thickness (IMT). Secondary endpoints included changes in flow mediated vasodilation (FMD), inflammatory markers, triglycerides and cholesterol. Patients were evaluated at time 0, and after 3, 6 and 12 months.

RESULTS

We enrolled 119 patients, stratified into three different groups: patients receiving atazanavir/ritonavir boosted (ATV/r) based regimens, efavirenz (EFV) based regimens and darunavir/ritonavir boosted (DRV/r) based regimens. At baseline, advanced naïve patients showed a relevant deterioration of CV conditions in terms of traditional CV risk factors, endothelial dysfunction and serum biomarkers. During the 12-month follow up period, mean blood lipids significantly increased: total cholesterol from 159 to 190 mg/dL, HDL-C from 31 to 41 mg/dL, and LDL-C from 99 to 117 mg/dL. D-dimers steadily decreased (median level 624 at baseline and 214 at T3), whereas ICAM and VCAM consistently raised. DRV/r and ATV/r determined a more marked decrease of D-dimers as compared to EFV. Regarding the epi-aortic changes (IMT >1 mm or presence of atherosclerotic plaques), patients in the DRV/r group were at risk of developing pathological IMT during the study (OR 6.0, 95% CI 0.9-36.9), as compared to EFV ones.

CONCLUSIONS

CV risk was elevated in advanced naïve patients and tended to remain high in the first year of therapy.

Association of T Cell and Macrophage Activation with Arterial Vascular Health in HIV

HIV-infected individuals are at increased risk of cardiovascular disease (CVD), but the arterial vascular functions affected by persistent innate and cellular immune activation are not well described. We assessed the relationship between immunologic and vascular parameters in 70 HIV-infected adults on efavirenz, tenofovir, and emtricitabine with more than 2 years of virologic suppression and no history of CVD. We measured brachial artery flow-mediated dilation (FMD) using ultrasound and circulating intercellular adhesion molecule 1 (ICAM-1) and vascular cell adhesion molecule 1 (VCAM-1) by multiple immunoassay. We also measured circulating naive (CD45RO^-CCR7⁺CD27⁺), activated (CD38⁺ and CD38⁺DR⁺), exhausted (PD1⁺), senescent (CD57⁺), and memory (CD45RO⁺) CD4⁺ and CD8⁺ T cell subsets by flow cytometry, and macrophage activation markers by ELISA and multiple immunoassay. Regression models were adjusted for age, sex, smoking, duration of antiretroviral therapy (ART), and body mass index. Median age was 45 years (IQR 39, 50), median CD4⁺ count 701 cells/μl (IQR 540, 954), and 43% were female. Lower brachial FMD was associated with a higher percentage of activated CD8⁺ T cells (p < .01), but not associated with macrophage activation. In contrast, higher ICAM-1 and VCAM-1 were associated with sCD163 (p < = .01 for both), macrophage inflammatory protein-1α (p < = .02 for both), and sCD14 (p = .01 for ICAM-1 only). These findings are consistent with the hypothesis that circulating CD8⁺ T cell activation may impair arterial smooth muscle relaxation, while macrophage activation has a role in the expression of endothelial cell proteins involved in immune cell translocation. Both innate and cellular immune activation appear to promote arterial vascular disease in HIV-infected persons on ART using differing mechanisms.

Resveratrol Co-Treatment Attenuates the Effects of HIV Protease Inhibitors on Rat Body Weight and Enhances Cardiac Mitochondrial Respiration

Since the early 1990s human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS) emerged as a global health pandemic, with sub-Saharan Africa the hardest hit. While the successful roll-out of antiretroviral (ARV) therapy provided significant relief to HIV-positive individuals, such treatment can also elicit damaging side-effects. Here especially HIV protease inhibitors (PIs) are implicated in the onset of cardio-metabolic complications such as type-2 diabetes and coronary heart disease. As there is a paucity of data regarding suitable co-treatments within this context, this preclinical study investigated whether resveratrol (RSV), aspirin (ASP) or vitamin C (VitC) co-treatment is able to blunt side-effects in a rat model of chronic PI exposure (Lopinavir/Ritonavir treatment for 4 months). Body weights and weight gain, blood metabolite levels (total cholesterol, HDL, LDL, triglycerides), echocardiography and cardiac mitochondrial respiration were assessed in PI-treated rats ± various co-treatments. Our data reveal that PI treatment significantly lowered body weight and cardiac respiratory function while no significant changes were found for heart function and blood metabolite levels. Moreover, all co-treatments ameliorated the PI-induced decrease in body weight after 4 months of PI treatment, while RSV co-treatment enhanced cardiac mitochondrial respiratory capacity in PI-treated rats. This pilot study therefore provides novel hypotheses regarding RSV co-treatment that should be further assessed in greater detail.

Lack of effects of statins on high-density lipoprotein subfractions in HIV-1-infected patients receiving protease inhibitors

BACKGROUND

We evaluated the effect of 45 days of rosuvastatin or pravastatin treatment on the distribution of HDL subfractions in HIV-1-infected individuals receiving boosted protease inhibitors (PIs) with cardiovascular risk.

METHODS

The distribution of HDL subclasses by gradient gel electrophoresis was blindly assessed in 74 HIV-1-infected individuals receiving boosted PIs at baseline and at day 45 of statin treatment, and compared with the distribution obtained in 63 healthy normolipidemic individuals taken as controls.

RESULTS

No significant modification appeared in HDL distribution between the two arms of statins for the HIV-1-infected individuals. Nevertheless, when compared to controls, HDL subfractions showed a significantly lower HDL2b proportion and significantly higher proportions of HDL2a and HDL3b (P<0.001).

CONCLUSION

No difference was observed in HDL distribution between pravastatin and rosuvastatin after 45 days treatment, in HIV-1-infected individuals under PIs. Nevertheless, when compared to healthy normolipidemic subjects, HDL distribution is clearly different, with a distribution in HIV-infected individuals under PIs associated with an increased cardiovascular risk.

Genetic polymorphisms in the CD14 gene are associated with monocyte activation and carotid intima-media thickness in HIV-infected patients on antiretroviral therapy

HIV-infected individuals on antiretroviral therapy (ART) are at increased risk of cardiovascular disease (CVD). Given the relationship between innate immune activation and CVD, we investigated the association of single-nucleotide polymorphisms (SNPs) in TLR4 and CD14 and carotid intima-media thickness (cIMT), a surrogate measurement for CVD, in HIV-infected individuals on ART and HIV-uninfected controls as a cross-sectional, case-control study. We quantified the frequency of monocyte subsets (CD14, CD16), markers of monocyte activation (CD38, HLA-DR), and endothelial adhesion (CCR2, CX3CR1, CD11b) by flow cytometry. Plasma levels of lipopolysaccharide, sCD163, sCD14, sCX3CL1, and sCCL2, were measured by ELISA. Genotyping of TLR4 and CD14 SNPs was also performed. The TT genotype for CD14/-260SNP but not the CC/CT genotype was associated with elevated plasma sCD14, and increased frequency of CD11b+CD14+ monocytes in HIV-infected individuals. The TT genotype was associated with lower cIMT in HIV-infected patients (n = 47) but not in HIV-uninfected controls (n = 37). The AG genotype for TLR4/+896 was associated with increased CX3CR1 expression on total monocytes among HIV-infected individuals and increased sCCL2 and fibrinogen levels in HIV-uninfected controls. SNPs in CD14/-260 and TLR4/+896 were significantly associated with different markers of systemic and monocyte activation and cIMT that differed between HIV-infected participants on ART and HIV-uninfected controls. Further investigation on the relationship of these SNPs with a clinical endpoint of CVD is warranted in HIV-infected patients on ART.

Urinary albumin-to-creatinine ratio is associated with endothelial dysfunction in HIV-infected patients receiving antiretroviral therapy

Endothelial dysfunction, a marker of cardiovascular (CV) risk, is common in human immunodeficiency virus (HIV)-infected patients. Microalbuminuria is frequent in HIV-infected patients, and is a predictor of renal impairment and CV risk. We investigated the association between microalbuminuria and endothelial dysfunction among HIV-infected patients receiving highly-active antiretroviral therapy (HAART). Endothelial function, measured by brachial artery flow-mediated dilatation (bFMD), and urine albumin-to-creatinine ratio (UACR), were measured in 170 HAART-treated HIV-infected adults. The relationship between UACR and bFMD was evaluated. The prevalence of increased UACR, defined by two cut-off levels (20 mg/g and 30 mg/g), was 29% and 17%. UACR was significantly higher while bFMD was lower among patients with metabolic syndrome (MS). UACR was associated with bFMD (r = −0.31; p < 0.001). This association was stronger in MS-patients (r = −0.44; p = 0.003). UACR above 20 mg/g was associated with an increased risk (OR 2.37, 95% CI 1.15–4.89, p = 0.020) of severely impaired bFMD (bFMD ≤ 2.1%). Patients with MS and increased UACR had the lowest bFMD compared with those with none or one of the two conditions. Microalbuminuria and endothelial dysfunction are positively associated in HIV-infected patients regardless of known confounders. The coexistence of microalbuminuria and MS amplifies their deleterious influence on endothelial function.

Efavirenz and ritonavir-boosted lopinavir use exhibited elevated markers of atherosclerosis across age groups in people living with HIV in Ethiopia

BACKGROUND

HIV patients on highly-active antiretroviral therapy (HAART) have shown elevated incidence of dyslipidemia, lipodystrophy, and markers of cardiovascular disease. Evidence is beginning to emerge that implicates efavirenz (EFV) as a potential mediator of early on-set cardiovascular disease.

METHODS

Pediatric and adult HIV-infected HAART-naïve, EFV-treated, nevirapine (NVP)-treated, and ritonavir-boosted lopinavir (LPV/r)-treated subjects were recruited from Black Lion Hospital in Addis Ababa, Ethiopia. Pulse wave velocity (PWV), carotid intima-media thickness (cIMT), carotid arterial stiffness, brachial artery flow-mediated dilation (FMD), body mass index, waist-to-hip circumference ratio, and skinfold thickness were measured. CD4+ cell count, fasting glucose, lipoprotein profiles and triglycerides were also determined. Results were segmented into pediatric (6-17 years of age), young adults (25-39 years old) and older adults (40-60 years old).

RESULTS

PWV was generally elevated in EFV- and LPV/r-treated subjects compared to NVP-treated subjects across age groups. cIMT was elevated in EFV- and LPV/r-treated compared to NVP-treated older adults and in EFV-treated compared to HAART-naïve older adults. FMD was impaired in EFV- and LPV/r-treated compared to HAART-naïve younger adults, in EFV-treated compared to NVP-treated young and older adults, and in LPV/r-treated compared to NVP-treated older adults. Differences in lipoprotein profiles and skinfold thickness with HAART regimen were observed in pediatric and young adults, but less so in older adults.

CONCLUSIONS

Whereas LPV/r and other protease inhibitors have long been recognized as mediators of HIV/HAART-associated atherosclerosis, this report supports the emerging evidence that EFV may also mediate cardiovascular disease in people living with HIV on HAART.

Heme oxygenase-1-derived bilirubin counteracts HIV protease inhibitor-mediated endothelial cell dysfunction

The use of HIV protease inhibitors (PIs) has extended the duration and quality of life for HIV-positive individuals. However there is increasing concern that this antiviral therapy may promote premature cardiovascular disease by impairing endothelial cell (EC) function. In the present study, we investigated the effect of HIV PIs on EC function and determined if the enzyme heme oxygenase (HO-1) influences the biological action of these drugs. We found that three distinct PIs, including ritonavir, atazanavir, and lopinavir, stimulated the expression of HO-1 protein and mRNA. The induction of HO-1 was associated with an increase in NF-E2-related factor-2 (Nrf2) activity and reactive oxygen species (ROS). PIs also stimulated HO-1 promoter activity and this was prevented by mutating the antioxidant responsive element or by overexpressing dominant-negative Nrf2. In addition, the PI-mediated induction of HO-1 was abolished by N-acetyl-l-cysteine and rotenone. Furthermore, PIs blocked EC proliferation and migration and stimulated the expression of intercellular adhesion molecule-1 and the adhesion of monocytes on ECs. Inhibition of HO-1 activity or expression potentiated the anti-proliferative and inflammatory actions of PIs which was reversed by bilirubin but not carbon monoxide. Alternatively, adenovirus-mediated overexpression of HO-1 attenuated the growth-inhibitory and inflammatory effect of PIs. In contrast, blocking HO-1 activity failed to modify the anti-migratory effect of the PIs. Thus, induction of HO-1 via the ROS-Nrf2 pathway in human ECs counteracts the anti-proliferative and inflammatory actions of PIs by generating bilirubin. Therapeutic approaches targeting HO-1 may provide a novel approach in preventing EC dysfunction and vascular disease in HIV-infected patients undergoing antiretroviral therapy.

Human immunodeficiency virus-associated heart failure in sub-Saharan Africa: evolution in the epidemiology, pathophysiology, and clinical manifestations in the antiretroviral era

The survival of patients with human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS) who have access to highly active antiretroviral therapy (ART) has dramatically increased in recent times. This review focuses on HIV‐associated heart failure in sub‐Saharan Africa (SSA). In HIV infected persons, heart failure may be related to pathology of the pericardium, the myocardium, the valves, the conduction system, or the coronary and pulmonary vasculature. HIV‐associated heart failure can be because of direct consequences of HIV infection, autoimmune reactions, pro‐inflammatory cytokines, opportunistic infections (OIs) or neoplasms, use of ART or therapy for OIs and presence of traditional cardiovascular risk factors. Myocardial involvement includes diastolic dysfunction, asymptomatic left ventricular dysfunction, cardiomyopathy, myocarditis, fibrosis, and steatosis. Pericardial diseases include pericarditis, pericardial effusions (rarely causing tamponade), pericardial constriction, and effusive‐constrictive syndromes. Coronary artery disease is commonly reported in industrial nations, although its prevalence is thought to be low in HIV‐infected persons from SSA.

Novel functions of PXR in cardiometabolic disease

Cardiometabolic disease emerges as a worldwide epidemic and there is urgent need to understand the molecular mechanisms underlying this chronic disease. The chemical environment to which we are exposed has significantly changed in the past few decades and recent research has implicated its contribution to the development of many chronic human diseases. However, the mechanisms of how exposure to chemicals contributes to the development of cardiometabolic disease are poorly understood. Numerous chemicals have been identified as ligands for the pregnane X receptor (PXR), a nuclear receptor functioning as a xenobiotic sensor to coordinately regulate xenobiotic metabolism via transcriptional regulation of xenobiotic-detoxifying enzymes and transporters. In the past decade, the function of PXR in the regulation of xenobiotic metabolism has been extensively studied by many laboratories and the role of PXR as a xenobiotic sensor has been well-established. The identification of PXR as a xenobiotic sensor has provided an important tool for the study of new mechanisms through which xenobiotic exposure impacts human chronic diseases. Recent studies have revealed novel and unexpected roles of PXR in modulating obesity, insulin sensitivity, lipid homeostasis, atherogenesis, and vascular functions. These studies suggest that PXR signaling may contribute significantly to the pathophysiological effects of many known xenobiotics on cardiometabolic disease in humans. The discovery of novel functions of PXR in cardiometabolic disease not only contributes to our understanding of "gene-environment interactions" in predisposing individuals to chronic diseases but also provides strong evidence to inform future risk assessment for relevant chemicals. This article is part of a Special Issue entitled: Xenobiotic nuclear receptors: New Tricks for An Old Dog, edited by Dr. Wen Xie.

Telmisartan to reduce cardiovascular risk in older HIV-infected adults: a pilot study

BACKGROUND

HIV-infected persons are at increased cardiovascular disease (CVD) risk, but traditional CVD therapies are understudied in this population. Telmisartan is an angiotensin receptor blocker (ARB) and peroxisome proliferator-activated receptor-gamma (PPAR-gamma) agonist that improves endothelial function and cardiovascular mortality in HIV-uninfected populations. We assessed the effects of telmisartan on endothelial function in older HIV-infected persons at risk for CVD in a small pilot study.

METHODS

HIV-infected individuals≥50 years old on suppressive antiretroviral therapy (ART) with ≥1 traditional CVD risk factor received open-label telmisartan 80 mg daily for 6 weeks. Brachial artery flow-mediated dilation (FMD) measured endothelial function. The primary endpoint was 6-week change in maximum relative FMD.

RESULTS

Seventeen participants enrolled; 16 completed all evaluations (88% men, 65% non-White, median age 60 years, CD4+T lymphocyte count 625 cells/mm3). Antiretroviral therapy included 71% protease inhibitor (PI), 29% non-nucleoside reverse transcriptase inhibitor (NNRTI), 29% integrase inhibitor, 65% tenofovir, and 29% abacavir. Cardiovascular disease risk factor prevalence included 76% hyperlipidemia, 65% hypertension, 18% smoking, and 12% diabetes mellitus. After 6 weeks, statistically significant blood pressure changes were observed (systolic-16.0 mmHg, diastolic-6.0 mmHg) without significant changes in FMD. In subset analyses, FMD increased more among abacavir-treated, PI-treated, and non-smoking participants.

CONCLUSIONS

No significant FMD changes were observed after 6 weeks of telmisartan therapy; however, abacavir- and PI-treated participants and non-smokers showed greater FMD increases. Additional studies are needed to explore the effects of telmisartan on endothelial function among HIV-infected individuals with traditional CVD and/or ART-specific risk factors.

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.

Efavirenz treatment causes arterial stiffening in apolipoprotein E-null mice

The development of highly active antiretroviral therapy (HAART) has transformed HIV-1 infection from a terminal diagnosis to a chronic, yet manageable disease. However, people living with HIV-1 exhibit a host of non-AIDS-related co-morbidities including cardiovascular disease (CVD). Several HAART drugs have been implicated in the development of CVD; however, the role of efavirenz (EFV), a highly prescribed HAART drug, in early-onset CVD is poorly understood. We treated apolipoprotein E-null (ApoE(-/-)) mice with EFV (75 mg/kg/day) or vehicle, via oral gavage, for 35 days and quantified commonly measured preclinical markers of CVD (intima-media thickening, arterial stiffening) and plaque area. Suprarenal abdominal aortas were subjected to cylindrical biaxial biomechanical testing and standard histology. Aortas from EFV-treated mice demonstrated decreased compliance (i.e., increased arterial stiffness) and decreased axial force and a trend toward decreased in vivo axial stretch, but EFV treatment had no effect on intima-media thickness of the aortic wall or plaque coverage in thoracic aortas and aortic arches. Taken together, these data suggest that EFV leads to arterial stiffening but, for the dose and duration tested, did not lead to elevated plaque progression in ApoE(-/-) mice.