Arterial inflammation in patients with HIV

Lipid Abnormalities and Inflammation in HIV Inflection

Infection with the human immunodeficiency virus (HIV), and subsequent treatment with antiretroviral therapy (ART), is often associated with perturbations in lipid profiles. Furthermore, persistent inflammation, in spite of suppression of viral replication by ART, likely contributes to modifications in lipid composition and function, exacerbating risk for development of cardiovascular disease (CVD). Increased levels of several pro-inflammatory lipid species, including oxidized low-density lipoprotein (LDL) and high-density lipoprotein (HDL), have been measured in HIV-infected persons and are associated with markers of immune activation. The mechanisms linked to this bidirectional relationship in which inflammation increases lipid levels and promotes their modification, and these modified lipid species perpetuate inflammatory processes, require further investigation. Treatment with statins and other lifestyle modifications, including improvement in dietary intake and exercise, are critical to reducing CVD risk. Well-designed clinical trials that take into account the complex relationships among lipids and inflammation within persons infected with HIV need to be considered.

Projecting 10-year, 20-year, and Lifetime Risks of Cardiovascular Disease in Persons Living With Human Immunodeficiency Virus in the United States

Background

Cardiovascular disease (CVD) is an increasing cause of morbidity among persons living with human immunodeficiency virus (HIV; PLWH). We projected cumulative CVD risk in PLWH in care compared to the US general population and persons HIV-uninfected, but at high risk for HIV.

Methods

We used a mathematical model to project cumulative CVD incidence. We simulated a male and female cohort for each of 3 populations: US general population; HIV-uninfected, at high risk for HIV; and PLWH. We incorporated the higher smoking prevalence and increased CVD risk due to smoking into the HIV-infected and HIV-uninfected, at high risk for HIV populations. We incorporated HIV-attributable CVD risk, independent of smoking.

Results

For men, life expectancy ranged from 70.2 to 77.5 years and for women from 67.0 to 81.1 years (PLWH, US general population). Without antiretroviral therapy, lifetime CVD risk for HIV-infected males and females was 12.9% and 9.0%. For males, by age 60, cumulative CVD incidence was estimated at 20.5% in PLWH in care, 14.6% in HIV-uninfected high-risk persons, and 12.8% in the US general population. For females, cumulative CVD incidence was projected to be 13.8% in PLWH in care, 9.7% for high-risk HIV-uninfected persons, and 9.4% in the US general population. Lifetime CVD risk was 64.8% for HIV-infected males compared to 54.8% for males in the US general population, but similar among females.

Conclusions

CVD risks should be a part of treatment evaluation among PLWH. CVD prevention strategies could offer important health benefits for PLWH and should be evaluated.

Lipodystrophy among HIV-Infected Patients Attending Care and Treatment Clinics in Dar es Salaam

Background

HIV infection and long-term HAART use are associated with metabolic and morphological changes. We assessed prevalence, types, and risk factors associated with lipodystrophy among HIV-infected adults attending CTC in Dar es Salaam, Tanzania.

Methods

Analysis included 466 HIV-infected patients. Study protocol involved administration of structured questionnaire to collect sociodemographic and clinical information. Diagnosis of lipodystrophy was based on physician clinical assessment.

Results

Lipodystrophy was present in 95 (20.4%) of the study participants, with lipoatrophy being the most common (49.5%) followed by mixed lipodystrophy (37.9%), and lipohypertrophy was the least prevalent (12.6%). Male gender, older age, long duration on HAART, and use of Stavudine containing regimen were associated with lipodystrophy (all p < 0.05). The risk for lipodystrophy was 1.6 times (AOR = 1.66, 95% CI = 1.01-2.72) for male participants and 13.3 times (AOR = 13.3, 95% CI = 6.4-27.7) for those on HAART. Long duration on HAART and use of Stavudine containing regimen were also associated with increased risk for lipodystrophy. Lipodystrophy was associated with poor perception about own body image and decreased social interactions.

Conclusions

Lipodystrophy is common among HIV-infected patients in Tanzania, especially among male patients and those on HAART. Regular screening, monitoring, and patient awareness are needed for early identification and appropriate management.

Cardiovascular Complications of HIV in Endemic Countries

Effective combination antiretroviral therapy (ART) has enabled human immunodeficiency virus (HIV) infection to evolve from a generally fatal condition to a manageable chronic disease. This transition began two decades ago in high-income countries and has more recently begun in lower income, HIV endemic countries (HIV-ECs). With this transition, there has been a concurrent shift in clinical and public health burden from AIDS-related complications and opportunistic infections to those associated with well-controlled HIV disease, including cardiovascular disease (CVD). In the current treatment era, traditional CVD risk factors and HIV-related factors both contribute to an elevated risk of myocardial infarction, stroke, heart failure, and arrhythmias. In HIV-ECs, the high prevalence of persons living with HIV and growing prevalence of CVD risk factors will contribute to a growing epidemic of HIV-associated CVD. In this review, we discuss the epidemiology and pathophysiology of cardiovascular complications of HIV and the resultant implications for public health efforts in HIV-ECs.

Unraveling Vascular Inflammation: From Immunology to Imaging

Inflammation is a critical factor in early atherosclerosis and its progression to myocardial infarction. The search for valid surrogate markers of arterial vascular inflammation led to the increasing use of positron emission tomography/computed tomography. Indeed, vascular inflammation is associated with future risk for myocardial infarction and can be modulated with short-term therapies, such as statins, that mitigate cardiovascular risk. However, to better understand vascular inflammation and its mechanisms, a panel was recently convened of world experts in immunology, human translational research, and positron emission tomographic vascular imaging. This contemporary review first strives to understand the diverse roles of immune cells implicated in atherogenesis. Next, the authors describe human chronic inflammatory disease models that can help elucidate the pathophysiology of vascular inflammation. Finally, the authors review positron emission tomography-based imaging techniques to characterize the vessel wall in vivo.

Metabolic syndrome and obesity are the cornerstones of liver fibrosis in HIV-monoinfected patients

BACKGROUND

Metabolic syndrome (MetS) and nonalcoholic fatty liver disease have become a common finding in HIV-infected patients. However, the severity, risk factors and pathogenesis of liver fibrosis in this population have been poorly documented.

OBJECTIVES

To assess the impact of MetS on liver fibrosis and analyze the association between MetS, liver fibrosis and markers of adipose tissue and macrophage activation.

METHODS

In a matched cohort of HIV-1-monoinfected patients with and without MetS, after exclusion of other causes of liver disease, we assessed liver stiffness measurement and measured levels of serum adipokines, homeostasis model assessment index and soluble CD163 (sCD163) and CD14 as markers of fat, insulin resistance and macrophage/monocyte activation, respectively.

RESULTS

A total of 468 HIV-monoinfected individuals were enrolled; 405 (203 with MetS/202 without MetS) were analyzed. Patients with MetS were older and 49% had insulin resistance. The prevalence of significant liver fibrosis (≥F2) was higher in patients with MetS [25.1%, 95% confidence interval (19.3-31.2)] compared with those without MetS [7.9%, (4.6-12.5), P < 0.0001]. In multivariate analysis with adjustment on MetS, obesity [odds ratio: 3.0 (1.1-8.4)] and homeostasis model assessment [1.1 (1.007-1.2)] were independent factors of advanced fibrosis (>= F3).. Serum levels of adipokines and sCD163 were significantly associated with the degree of liver fibrosis. When adjusted on MetS, leptin and sCD163 remained strongly associated with fibrosis/cirrhosis, whereas HIV parameters and antiretroviral therapy were not.

CONCLUSION

In HIV-monoinfected patients, MetS is an important risk factor of liver fibrosis. Adipose tissue and macrophage activation might be key players in the development of liver fibrosis but the exact mechanisms need to be elucidated.

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.

Soluble TWEAK may predict carotid atherosclerosis in treated HIV infection

BACKGROUND

Soluble Tumor Necrosis Factor Weak Inducer of Apoptosis (sTWEAK) has been proposed as a novel biomarker of cardiovascular disease risk. This study compares levels of sTWEAK, sCD163 and the sCD163/sTWEAK ratio in HIV-infected and uninfected patients and their associations with cardiovascular and inflammatory factors.

METHODS

The data for our analysis come from 274 HIV-infected adults and 59 controls. HIV participants were on stable antiretroviral therapy (ART). Wilcoxon-Mann-Whitney tests were used for comparing markers between HIV-infected participants with HIV viral load <50 copies/mL (aviremic group), HIV-infected participants with detectable viremia (HIV-1 RNA ≥50 copies/mL; viremic group) and HIV negative participants. Multivariable quantile regression analyses were used to assess associations of sTWEAK and sCD163 with other markers of inflammation and carotid intima-media thickness (cIMT).

RESULTS

Overall, 74% of participants were male; 59% were African-Americans; median age was 40 years and CD4 595 cells/mm3. Overall, HIV-infected participants had reduced sTWEAK and increased sCD163 levels compared to HIV-uninfected participants (p = 0.0001 for both markers). In addition, these biomarkers were significantly different between HIV-infected viremic and aviremic patients (p ≤ 0.01 for both markers). In multivariable models, sTWEAK and sCD163 in aviremic patients were significantly correlated with common carotid artery IMT (p ≤ 0.05). In HIV-infected aviremic participants, sTWEAK and sCD163 were both associated with IL-6, CD14 + CD16 + monocytes (p ≤ 0.02); additionally, sCD163 was associated with D-dimer- (β = -69.5, 0.05), VCAM (β = 72.4, p = 0.05), TNF RI (β = 91.1, p < 0.01), and TNF RII (β = 87.8, p < 0.01).

CONCLUSIONS

HIV-infected participants showed increased systemic inflammatory and monocyte activation markers. Soluble CD163 and sTWEAK levels were associated with carotid intima-media thickness.

HIV-1-Associated Atherosclerosis: Unraveling the Missing Link

Cardiovascular disease, including atherosclerosis and atherosclerosis-associated complications, is an increasing cause of morbidity and mortality in human immunodeficiency virus (HIV) patients in the post-antiretroviral therapy era. HIV alone accelerates atherosclerosis. Antiretroviral therapy; HIV-associated comorbidities, such as dyslipidemia, drug abuse, and opportunistic infections; and lifestyle are risk factors for HIV-associated atherosclerosis. However, our current understanding of HIV-associated atherogenesis is very limited and has largely been obtained from clinical observation. There is a pressing need to experimentally unravel the missing link between HIV and atherosclerosis. Understanding these mechanisms will help to better develop and design novel therapeutic interventions for the treatment of HIV-associated cardiovascular disease. HIV mainly infects T cells and macrophages resulting in the induction of oxidative and endoplasmic reticulum stress, the formation of the inflammasome, and the dysregulation of autophagy. These mechanisms may contribute to HIV-associated atherogenesis. In this review, we will summarize our current understanding and propose potential mechanisms of HIV-associated atherosclerosis.

Application of a Novel CD206+ Macrophage-Specific Arterial Imaging Strategy in HIV-Infected Individuals

Background

The ability to noninvasively assess arterial CD206+ macrophages may lead to improved understanding of human immunodeficiency virus (HIV)-associated cardiovascular disease.

Methods

We trialed a novel macrophage-specific arterial imaging technique.

Results

We demonstrated colocalization between technetium Tc 99m tilmanocept (99mTc-tilmanocept) and CD206+ macrophages ex vivo. In vivo application of 99mTc-tilmanocept single-photon emission computed tomography/computed tomography revealed high-level 99mTc-tilmanocept uptake across 20.4% of the aortic surface volume among HIV-infected subjects, compared with 4.3% among non-HIV-infected subjects (P = .009). Among all subjects, aortic high-level 99mTc-tilmanocept uptake was related to noncalcified aortic plaque volume (r = 0.87; P = .003) on computed tomographic angiography, and this relationship held when we controlled for HIV status.

Conclusion

These first-in-human data introduce a novel macrophage-specific arterial imaging technique in HIV.

Clinical Trials Registration

NCT02542371.

Subclinical atherosclerosis in low Framingham risk HIV patients

BACKGROUND

Pathogenesis of atherosclerosis is complex, and differences between HIV-infected patients and general population cannot be completely explained by the higher prevalence of traditional cardiovascular risk factors. We aimed to analyse the association between inflammation and subclinical atherosclerosis in HIV patients with low Framingham risk score.

MATERIALS AND METHODS

Case-control study.

SETTING

Outpatient Infectious Diseases clinic in a university hospital.

SUBJECTS

HIV-1-infected patients aged > 35 years receiving antiretroviral treatment with viral load < 50 copies/mL and Framingham risk score < 10%.

EXCLUSION CRITERIA

inflammatory diseases; dyslipidaemia requiring statins; smoking > 5 cigarettes/day; diabetes; hypertension; vascular diseases.

MAIN OUTCOME

subclinical atherosclerosis determined by ultrasonography: common carotid intima-media thickness greater than 0·8 mm or carotid plaque presence. Explanatory variables: ribosomal bacterial DNA (rDNA), sCD14, interleukin-6 (IL-6) and TNF-α.

RESULTS

Eighty-four patients were included, 75% male, mean age 42 years and mean CD4+ cells 657 ± 215/mm³ . Median Framingham risk score was 1% at 10 years (percentile 25-75: 0·5-4%). Eighteen patients (21%) had subclinical atherosclerosis; the associated factors were older age (P = 0·001), waist-hip ratio (P = 0·01), time from HIV diagnosis (P = 0·02), rDNA (P = 0·04) and IL-6 (P = 0·01). In multivariate analysis, OR for subclinical atherosclerosis was 7 (95% CI, 1.3-40, P = 0.02) and 9 (95% CI, 1.0-85, P = 0.04) for patients older than 44 years and IL-6 > 6·6 pg/mL, respectively.

CONCLUSIONS

Well-controlled HIV patients with low Framingham risk score have a high prevalence of subclinical carotid atherosclerosis, and the main risk factors are age and inflammation. These patients are not receiving primary prophylaxis for cardiovascular events according to current guidelines.

Acute hyperinsulinemia effects on systemic markers of immune activation in HIV

: The well treated HIV population remains at risk for insulin resistance and chronic immune activation. We tested the effects of acute hyperinsulinemia on inflammation in HIV. Twenty HIV-infected and 10 non-HIV-infected individuals well matched for BMI underwent oral glucose tolerance testing to stimulate insulin secretion and assess for changes in circulating soluble CD163, soluble CD14, and monocyte chemoattract protein 1. Soluble CD14 decreased significantly after stimulation of hyperinsulinemia and no significant changes in soluble CD163 or monocyte chemoattract protein 1 were demonstrated in HIV-infected and non-HIV-infected groups.

HIV Infection and Risk of Cardiovascular Diseases Beyond Coronary Artery Disease

PURPOSE OF REVIEW

Cardiovascular disease (CVD) increasingly afflicts people living with HIV (PLWH) in the contemporary era of antiretroviral therapy (ART). Coronary artery disease (CAD) is the most widely studied cardiovascular problem in PLWH; however, less is known about other clinically relevant subtypes of CVD such as heart failure (HF), cerebrovascular disease, sudden cardiac death, pericardial diseases, and pulmonary hypertension. This paper reviews evidence of other subtypes of CVD as emerging issues in the post-ART era.

RECENT FINDINGS

Recent studies have shown that PLWH have higher risk of HF as well as subclinical impairment of left ventricular (LV) mechanics (systolic and diastolic dysfunction) and myocardial abnormalities (fibrosis and steatosis). The underlying mechanisms, however, are not well-understood. A few studies have also shown higher rates of atrial fibrillation and sudden cardiac death in PLWH. Ischemic stroke is the most common stroke type in the post-ART era, with underlying mechanisms like those identified in CAD: chronic inflammation and associated vasculopathy. Studies of great vessels (carotid artery and aorta) and peripheral arterial disease show heterogeneous results. Small subclinical pericardial effusions are common in PLWH in post-ART era. Pulmonary hypertension continues to be an underdiagnosed and potentially fatal complication of HIV infection. PLWH remain at higher risk for all types of CVD including heart failure, stroke, and arrhythmias in the post-ART era. Chronic inflammation may play an important role in this increased risk. More studies are needed to further elucidate the extent of non-coronary CVD in PLWH and the underlying mechanisms for them.

Pre-clinical carotid atherosclerosis and sCD163 among virally suppressed HIV patients in Botswana compared with uninfected controls

Objectives

Human immune deficiency virus (HIV) is associated with increased cardiovascular disease (CVD) risk, yet the relationship between HIV and carotid atherosclerosis / monocyte activation among virally suppressed HIV-infected patients in sub-Saharan Africa is not well understood.

Methods

We measured traditional CVD risk factors, bilateral distal common carotid intima media thickness (cIMT), presence of carotid plaque and plasma sCD163 levels among virally suppressed HIV-infected adults and HIV-uninfected controls, in a cross-sectional study in Gaborone, Botswana. The associations between HIV status, traditional CVD risk factors, sCD163 and outcome of cIMT were assessed in univariate and multivariate linear regression models.

Results

We enrolled 208 HIV-infected adults (55% Female, mean age 39 years) who had undetectable HIV-1 RNA on antiretroviral therapy and 224 HIV-uninfected controls (47% Female, mean age 37 years). There was no difference in cIMT between study groups, with mean cIMT 0.607mm and 0.599mm in HIV-infected and HIV-uninfected, respectively (p = 0.37). Plasma sCD163 was significantly higher in HIV-infected versus HIV-uninfected persons (1917ng/ml vs 1593ng/ml, p = 0.003), but was not associated with cIMT (p = 0.43 among all, p = 0.72 for HIV-infected only). In the final multivariate model, increased cIMT was associated with older age, being treated for hypertension, and higher non-HDL cholesterol among all (p<0.001, p = 0.03, p<0.001 respectively), and with older age and waist-hip ratio in HIV-infected participants (p = 0.02 & p = 0.02 respectively). Carotid plaque was present in a significantly higher proportion of HIV-infected adults (RR 2.15, 95% CI 1.22, 3.81).

Conclusions

HIV-infected participants aged 30–50 years who have achieved viral suppression did not have increased cIMT when compared to HIV-uninfected controls in Botswana. However, well-controlled HIV was associated with excess monocyte activation. Future work should explore the impact of subclinical atherosclerosis on CVD events among HIV-infected and -uninfected adults in Botswana.

Brief Report: Soluble CD163 in CMV-Infected and CMV-Uninfected Subjects on Virologically Suppressive Antiretroviral Therapy in the ICONA Cohort

AIMS

To contribute to the understanding of the role played by cytomegalovirus (CMV) in sustaining monocyte/macrophage-mediated immune activation in antiretroviral therapy treated HIV-infected subjects.

DESIGN AND METHODS

We selected 23 CMV-uninfected and 46 CMV-infected HIV+ subjects, matched for age, CD4 nadir, HIV infection duration, and viral hepatitis serostatus. All subjects were on successful antiretroviral therapy since at least 1 year. A group of 16 healthy donors with similar age and sex was also included. Plasma levels of tumor necrosis factor-alpha, interleukin-6, sCD163, sCD14, and CMV immunoglobulin G levels were measured in duplicate with human enzyme-linked immunosorbent assay kits.

RESULTS

We found significantly higher sCD163 plasma levels in HIV+CMV+ compared with HIV+CMV- subjects and healthy donors. This augmentation was confirmed also when subjects positive for hepatitis C virus-Ab were excluded from analysis. Interestingly, a correlation between anti-CMV immunoglobulin G levels and sCD163, tumor necrosis factor-alpha, interleukin-6, and sCD14 in HIV+CMV+ subjects was found.

CONCLUSIONS

CMV coinfection could be a major driver of monocyte/macrophage activation in virally suppressed HIV+ individuals and might explain the increased risk of non-AIDS morbidity/mortality in HIV/CMV-coinfected subjects.

Direct Targeting of Macrophages With Methylglyoxal-Bis-Guanylhydrazone Decreases SIV-Associated Cardiovascular Inflammation and Pathology

BACKGROUND

Despite effective combination antiretroviral therapy, HIV-infected individuals develop comorbidities, including cardiovascular disease, where activated macrophages play a key role. To date, few therapies target activated monocytes and macrophages.

METHODS

We evaluated a novel oral form of the polyamine biosynthesis inhibitor methylglyoxal-bis-guanylhydrazone (MGBG) on cardiovascular inflammation, carotid artery intima-media thickness (cIMT), and fibrosis in a simian immunodeficiency virus infection model of AIDS. Eleven simian immunodeficiency virus-infected animals received MGBG (30 mg/kg) once daily and 8 received a placebo control both beginning at 21 days postinfection (dpi). Animals were time sacrificed at 49 days post infection (dpi), when their matched placebo controls developed AIDS (63, 70, 77, 80), or at the study end-point (84 dpi). Aorta, carotid artery, and cardiac tissues were analyzed. Quantitative analyses of macrophage populations and T lymphocytes were done and correlated with cIMT and fibrosis.

RESULTS

MGBG treatment resulted in 2.19-fold (CD163), 1.86-fold (CD68), 2.31-fold (CD206), and 2.12-fold (MAC387) decreases in macrophages in carotid arteries and significant 2.07-fold (CD163), 1.61-fold (CD68), 1.95-fold (MAC387), and 1.62-fold (CD206) decreases in macrophages in cardiac tissues. cIMT (1.49-fold) and fibrosis (2.05-fold) also were significantly decreased with MGBG treatment. Numbers of macrophage and the degree of fibrosis in treated animals were similar to uninfected animals. A positive correlation between decreased macrophage in the carotid artery and cIMT, and cardiac macrophages and fibrosis was found.

CONCLUSIONS

These data demonstrate that directly targeting macrophages with MGBG can reduce cardiovascular inflammation, cIMT, and fibrosis. They suggest that therapies targeting macrophages with HIV could be used in conjunction with combination antiretroviral therapy.

Metabolic Syndrome After HIV Acquisition in South African Women

BACKGROUND

Noncommunicable diseases are common among chronically infected patients with HIV in the developed world, but little is known about these conditions in African cohorts. We assessed the epidemiology of metabolic syndrome among young South African women during the first 3 years after HIV acquisition.

METHODS

A total of 160 women were followed prospectively in the CAPRISA 002 Acute Infection study. Metabolic syndrome was defined as a constellation of hyperlipidemia, hypertension, hyperglycemia/diabetes, and abdominal obesity. Time trends were assessed using generalized estimation equation models.

RESULTS

Median age was 24 years and body mass index 27 kg/m. Prevalence of metabolic syndrome at infection was 8.7% increasing to 19.2% over 36 months (P = 0.001). The proportion of women with body mass index >30 kg/m increased from 34.4% to 47.7% (P = 0.004), those with abnormal waist circumference and elevated blood pressure increased from 33.5% to 44.3% (P = 0.060) and 23.8% to 43.9% (P < 0.001), respectively. Incidence of metabolic syndrome was 9.13/100 person-years (95% CI: 6.02 to 13.28). Predictors of metabolic syndrome were age (per year increase odds ratio (OR) = 1.12; 95% CI: 1.07 to 1.16), time postinfection (per year OR = 1.47; 95% CI: 1.12 to 1.92), family history of diabetes (OR = 3.13; 95% CI: 1.71 to 5.72), and the human leukocyte antigen (HLA)-B*81:01 allele (OR = 2.95; 95% CI: 1.21 to 7.17), whereas any HLA-B*57 or B*58:01 alleles were protective (OR = 0.34; 95% CI: 0.15 to 0.77). HIV-1 RNA (OR = 0.89; 95% CI: 0.62 to 1.27) and CD4 count (OR = 1.03; 95% CI: 0.95 to 1.11) did not predict metabolic syndrome.

CONCLUSIONS

The high burden of metabolic conditions in young South African HIV-infected women highlights the need to integrate noncommunicable disease and HIV care programs. Interventions to prevent cardiovascular disease must start at HIV diagnosis, rather than later during the disease course.

Comparison of the Peripheral Reactive Hyperemia Index with Myocardial Perfusion Reserve by 82Rb PET/CT in HIV-Infected Patients

After the introduction of antiretroviral therapy (ART) the life expectancy of patients infected with human immunodeficiency virus (HIV) is now approaching that of the general population and the importance of non-AIDS co-morbidities is increasing. Specifically, the risk of coronary artery disease (CAD) seems to be higher in HIV-infected patients and an accurate risk prediction of CAD is of high importance for optimal long term treatment. In this study, we assessed the correlation of the endoPAT, which is an office-based CVD screening tool with the myocardial perfusion reserve by ⁸²-rubidium PET/CT. We measured the reactive hyperemia index, which is a measure of the endothelial responsiveness, by the use of an endoPAT device (Itamar Medical, Caesarea, Israel) in 48 ART treated HIV-infected patients with high CD 4 cell counts and viral suppression (HIV-RNA < 20 copies/mL), who had previously undergone measurement of the myocardial perfusion reserve by ⁸²-rubidium PET/CT for study purposes. We found an inverse correlation between the reactive hyperemia index and the myocardial perfusion reserve which most likely indicates different vascular physiology. This study did not find evidence to suggest the immediate implementation of the reactive hyperemia index as a screening tool for early coronary artery disease in well-treated HIV-infected patients pending further validation in larger prospective studies.

HIV infection as vascular risk: A systematic review of the literature and meta-analysis

IMPORTANCE

The vascular risk attributable to HIV infection is rising. The heterogeneity of the samples studied is an obstacle to understanding whether HIV is a vascular risk across geographic regions.

OBJECTIVE

To test the hypothesis that HIV infection is a vascular risk factor, and that the risk conferred by HIV varies by geographical region.

DATA SOURCES

A systematic search of publications was carried out in seven electronic databases: PubMed, The Cochrane Library, EMBASE, Web of Science, LILACS, ClinicalTrials.gov, and WHO International Clinical Trials Registry Platform from inception to July 2015.

STUDY SELECTION

We included longitudinal studies of HIV+ individuals and their risk of vascular outcomes of ≥ 50 HIV+ cases and excluded studies on biomarkers of vascular disease as well as clinical trials.

DATA EXTRACTION AND SYNTHESIS

Data was extracted by one of the authors and independently confirmed by the other two authors. We used incidence rate (IR), incidence risk ratio (IRR) and hazard ratio (HR) with their 95% confidence intervals as measures of risk.

MAIN OUTCOME

All-death, myocardial infarction (MI), coronary heart disease (CHD), any stroke, ischemic stroke (IS) or intracranial hemorrhage (ICH).

RESULTS

We screened 11,482 references for eligibility, and selected 117 for analysis. Forty-four cohorts represented 334,417 HIV+ individuals, 49% from the United States. Compared with their European counterparts, HIV+ individuals in the United States had higher IR of death (IRR 1.78, 1.69-1.88), MI (IRR 1.61, 1.29-2.01), CHD (IRR 2.27, 1.92-2.68), any stroke (IRR 1.94, 1.59-2.38), IS (IRR 1.56, 1.23-1.98), and ICH (IRR 4.03, 2.72-6.14). Compared with HIV- controls and independent of geographical region, HIV was a risk for death (HR 4.77, 4.55-5.00), MI (HR 1.60, 1.49-1.72), any CHD (HR 1.20, 1.15-1.25), any stroke (HR 1.82, 1.53-2.16), IS (HR 1.27, 1.15-1.39) and ICH (HR 2.20, 1.61-3.02). Use of antiretroviral therapy was a consistent risk for cardiac outcomes, while immunosuppression and unsuppressed viral load were consistent risks for cerebral outcomes.

CONCLUSIONS

HIV should be considered a vascular risk, with varying magnitudes across geographical and anatomical regions. We think that strategies to reduce the HIV-related vascular burden are urgent, and should incorporate the disparities noted here.

Soluble CD163 predicts incident chronic lung, kidney and liver disease in HIV infection

OBJECTIVE

To examine if monocyte and macrophage activity may be on the mechanistic pathway to non-AIDS comorbidity by investigating the associations between plasma-soluble CD163 (sCD163) and incident non-AIDS comorbidities in well treated HIV-infected individuals.

DESIGN

Prospective single-center cohort study.

METHODS

Plasma sCD163 was quantified by ELISA technique at study entry in 2004/2005, and non-AIDS comorbidity was identified by International Classification of Disease Tenth revision diagnosis codes and registry linkage in 2015. Associations between sCD163 and incident comorbidity was examined using multivariable Cox proportional hazards models adjusted for pertinent covariates.

RESULTS

In HIV-1-infected individuals (n = 799), the highest quartile of plasma sCD163 was associated with incident chronic lung disease [adjusted hazard ratio (aHR), 3.2; 95% confidence interval (CI): 1.34; 7.46] and incident chronic kidney disease (aHR, 10.94; 95% CI: 2.32; 51.35), when compared with lowest quartiles. Further, (every 1 mg) increase in plasma sCD163 was positively correlated with incident liver disease (aHR, 1.12; 95% CI: 1.05; 1.19). The sCD163 level was not associated with incident cancer, cardiovascular disease or diabetes mellitus.

CONCLUSION

sCD163 was independently associated with incident chronic kidney disease, chronic lung disease and liver disease in treated HIV-1-infected individuals, suggesting that monocyte/macrophage activation may be involved in the pathogenesis of non-AIDS comorbidity and a potential target for therapeutic intervention.

Intermittent hypoxia in obstructive sleep apnoea mediates insulin resistance through adipose tissue inflammation

Obstructive sleep apnoea (OSA) is increasingly associated with insulin resistance. The underlying pathophysiology remains unclear but intermittent hypoxia (IH)-mediated inflammation and subsequent dysfunction of the adipose tissue has been hypothesised to play a key role.We tested this hypothesis employing a comprehensive translational approach using a murine IH model of lean and diet-induced obese mice, an innovative IH system for cell cultures and a tightly controlled patient cohort.IH led to the development of insulin resistance in mice, corrected for the degree of obesity, and reduced insulin-mediated glucose uptake in 3T3-L1 adipocytes, associated with inhibition of the insulin-signalling pathway and downregulation of insulin-receptor substrate-1 mRNA. Providing mechanistic insight, IH induced a pro-inflammatory phenotype of visceral adipose tissue in mice with pro-inflammatory M1 macrophage polarisation correlating with the severity of insulin resistance. Complimentary in vitro analysis demonstrated that IH led to M1 polarisation of THP1-derived macrophages. In subjects without comorbidities (n=186), OSA was independently associated with insulin resistance. Furthermore, we found an independent correlation of OSA severity with the M1 macrophage inflammatory marker sCD163.This study provides evidence that IH induces a pro-inflammatory phenotype of the adipose tissue, which may be a crucial link between OSA and the development of insulin resistance.

Effects of pitavastatin and pravastatin on markers of immune activation and arterial inflammation in HIV

OBJECTIVE

Persistent immune activation is thought to contribute to increased cardiovascular disease risk in HIV and statins may help modulate systemic immune activation. We aimed to compare the effects of two key statins on markers of systemic immune activation and arterial inflammation in the HIV population.

DESIGN

Double-blind, active-controlled, parallel-group comparative trial performed in 45 sites.

METHODS

Two hundred and fifty-two antiretroviral therapy-treated HIV-infected participants with dyslipidemia were randomized (1 : 1) to pitavastatin 4 mg daily vs. pravastatin 40 mg daily in the HIV-infected patieNts and TREatment with PItavastatin vs. pravastatin for Dyslipidemia (INTREPID) trial. In this analysis of the INTREPID trial, we assessed markers of immune activation and arterial inflammation using a modified intent-to-treat population. This trial is registered with ClinicalTrials.gov (NCT01301066).

RESULTS

One hundred and twenty-six participants were randomized to receive pitavastatin and 126 to pravastatin. Ninety-nine participants in the pitavastatin group and 91 participants in the pravastatin group completed the study. Median age was 50 (45, 56) years [median (interquartile range)]. Baseline, low-density lipoprotein-cholestrol (LDL-C) was 153 (135, 171) mg/dl, log HIV-1 viral load was 1.1 ± 0.2 copies/ml, and CD4 cell count was 580 (439, 794) cells/μl. At week 52, the pitavastatin group had a significantly greater reduction (% change) compared with pravastatin in soluble CD14 (sCD14), (-10.0 vs. 0.6%, P = 0.02), oxidized LDL (oxLDL) (-26.9 vs. -17.5%, P = 0.02), and lipoprotein-associated phospholipase 2 (Lp-PLA2) (-26.6 vs. -15.5%, P = 0.005) (pitavastatin vs. pravastatin).

CONCLUSION

Fifty-two weeks of pitavastatin 4 mg daily (vs. pravastatin 40 mg daily) led to a greater reduction in select markers of immune activation and arterial inflammation (sCD14, oxLDL, and LpPLA2) among HIV-infected participants. Further work is needed to assess whether immune-modulatory effects of pitavastatin reduce cardiovascular disease risk in HIV.

Soluble Levels of Receptor for Advanced Glycation Endproducts (RAGE) and Progression of Atherosclerosis in Individuals Infected with Human Immunodeficiency Virus: ACTG NWCS 332

Identification of biomarkers and/or mediators of cardiovascular disease (CVD) associated with HIV infection would be of diagnostic and therapeutic value. As soluble receptor for advanced glycation endproducts (sRAGE) and endogenous secretory (esRAGE) have been implicated in vascular complications in other settings, we investigated whether either soluble form of RAGE was associated with changes in carotid intima-media thickness (CIMT) in HIV-infected patients and HIV-uninfected controls. We found no differences in sRAGE, esRAGE, or CIMT among groups at study entry, or in yearly rates of change in sRAGE, esRAGE, or CIMT by HIV-serostatus (all p > 0.10). However, yearly rates of change in sRAGE (p = 0.07) and esRAGE (p < 0.001) were higher in those taking protease inhibitors, and lower baseline esRAGE levels (p = 0.06) were associated with increased odds of CIMT progression in HIV-infected individuals. Although esRAGE was not altered by HIV-serostatus (p = 0.17), its inverse relationship with CIMT progression in HIV-infected patients suggests a possible role as a mediator of CVD in HIV-infected persons.

Psoriasis as a human model of disease to study inflammatory atherogenesis

Inflammation is known to play a significant role in the process of atherogenesis and cardiovascular disease (CVD). Indeed, patients with chronic inflammatory diseases are at increased risk for cardiovascular events. However, the mechanisms linking chronic inflammation and CVD remain poorly understood. Psoriasis, a chronic inflammatory skin disease associated with a greater risk of early cardiovascular events, provides a suitable human model to study the pathophysiology of inflammatory atherogenesis in humans. Additionally, cytokines such as TNF-α, IL-17A, and other immune pathways are the common links between the pathogenesis of psoriasis and atherosclerosis, and hence the approved treatments for psoriasis, which include selective cytokine inhibition (e.g., anti-TNF, anti-IL-17A, and anti-IL-12/23) and immune modulation (e.g., methotrexate or cyclosporine), provide an opportunity to examine the effect of modulating these pathways on atherogenesis. We have been using this human model in a large, prospective cohort study, and this review summarizes our approach and results of using this human model to study inflammatory atherogenesis. Specifically, we review simultaneous multimodal imaging of several vascular beds using ¹⁸fludeoxyglucose positron emission tomography/computed tomography, ¹⁸fludeoxyglucose positron emission tomography/MRI, and coronary computed tomography angiography as well as cardiovascular biomarkers to better understand how modulation of inflammation may impact vascular diseases.

Interleukin-1 receptor antagonist, a biomarker of response to anti-TB treatment in HIV/TB co-infected patients

OBJECTIVES

Despite the high frequency of tuberculosis-associated immune reconstitution inflammatory syndrome (TB-IRIS) in human immunodeficiency virus (HIV)/TB co-infected patients, no diagnostic test is available. Here, we investigated whether monocyte/macrophage activation markers can predict TB-IRIS occurrence and if they are modulated by anti-TB treatment.

METHODS

Frozen plasma was obtained from 127 HIV/TB co-infected adults naïve for antiretroviral therapy, enrolled in the CAMELIA trial, 36 of whom developed TB-IRIS. Concentrations of IL-1Ra, sCD14, and sCD163 were measured at anti-TB treatment onset (baseline), after 8 weeks of anti-TB treatment and at TB-IRIS time.

RESULTS

At baseline, IL-1Ra and sCD14 concentrations were similar in TB-IRIS and non-IRIS patients. sCD163 concentrations, although significantly higher in TB-IRIS patients, did not remain associated with TB-IRIS occurrence in multivariate analysis. At the time of TB-IRIS, patients displayed higher concentrations of IL-1Ra (p = 0.002) and sCD14 (p < 0.001). The most striking result was the significant decrease in IL-1Ra after 8 weeks of anti-TB treatment (median reduction: -63% (p < 0.0001)).

CONCLUSIONS

None of the biomarkers tested was associated with TB-IRIS occurrence. However, repeated measurement of IL-1Ra could help for the diagnosis of TB-IRIS. The substantial reduction of IL-1Ra under treatment suggests that IL-1Ra could be a surrogate biomarker of anti-TB treatment response in HIV-infected patients.

Association of Arterial and Lymph Node Inflammation With Distinct Inflammatory Pathways in Human Immunodeficiency Virus Infection

Importance

Human immunodeficiency virus (HIV) infection is associated with a high risk of cardiovascular disease and increased arterial inflammation. In HIV, inflammation is also increased within lymph nodes (LNs), tissues known to harbor the virus even among treated and suppressed individuals.

Objective

To test the hypothesis that arterial inflammation is linked to HIV disease activity and to inflammation within HIV-infected tissues (LNs).

Design, Setting, and Participants

For this case-control study, participants were recruited from the SCOPE (Observational Study of the Consequences of the Protease Inhibitor Era) cohort, a clinic-based cohort of individuals receiving care at San Francisco General Hospital and the San Francisco Veteran's Affairs Medical Center. Arterial and LN inflammation were measured using 18F-fluorodeoxyglucose positron emission tomography. Detailed immunophenotyping was performed, along with measurement of viral activity/persistence and of circulating inflammatory biomarkers.

Main Outcomes and Measures

Arterial and LN inflammation.

Results

A total of 74 men were studied (45 HIV-infected men with a median age of 53 years [interquartile range, 49-59 years] and 29 uninfected male controls with a median age of 52 years [interquartile range, 46-56 years]). Lymph node inflammation was higher in HIV-infected individuals and correlated with markers of viral disease activity (viral load, CD8+ T cells, and CD4/CD8 ratio) and CD4+ T-cell activation. Uninfected controls had the lowest LN activity (mean [SD] maximum axillary LN standardized uptake value, 1.53 [0.56]), the elite controller and ART-suppressed groups had intermediate levels of LN (mean [SD] maximum axillary LN standardized uptake value, 2.12 [0.87] and 2.32 [1.79], respectively), and the noncontrollers had the highest activity (mean [SD] maximum axillary LN standardized uptake value, 8.82 [3.08]). Arterial inflammation was modestly increased in HIV-infected individuals and was positively correlated with circulating inflammatory biomarkers (high-sensitivity C-reactive protein and IL-6) and activated monocytes (CD14dimCD16+; nonclassical) but not with markers of HIV. While LN and arterial inflammation were increased in HIV, inflammatory activity in these tissues was not related (r = 0.09, P = .56).

Conclusions and Relevance

While LNs and, to a lesser degree, the arterial wall are inflamed in HIV, inflammation in these tissues is not closely linked. Namely, measures of HIV disease activity are strongly associated with LN inflammation but not with arterial inflammation. These data suggest that LN and arterial inflammation do not share underlying pathways of immune activation and also that therapeutic interventions that reduce viral disease activity may not predictably reduce arterial inflammation in HIV or its downstream consequence (ie, cardiovascular disease).

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.

Association between Immune Markers and Surrogate Markers of Cardiovascular Disease in HIV Positive Patients: A Systematic Review

Background

HIV infection is associated with an increased risk of cardiovascular disease (CVD). Chronic low-grade immune activation is likely one of the driving mechanisms. This systematic review provides an overview of the evidence addressing the relation between immune markers and surrogate markers of CVD (except CIMT) in HIV infection.

Methods

A systematic search was performed in PubMed, Embase and Cochrane Library identifying all articles from 1996 to April 2015. It addressed the relation between immune markers and surrogate markers of CVD (except Carotid Intima-media Thickness) in HIV-positive adults. Two authors, using predefined criteria, independently conducted the selection of articles, critical appraisal and extraction of the data. Analysis focused on immune markers that were assessed most frequently. The review was conducted according to the PRISMA guideline and performed as part of an overarching review registered with PROSPERO (CRD42014010516).

Findings

Twenty-nine articles were selected, describing 34 immune markers and nine different CVD surrogate outcomes: coronary calcium score (13 times) and flow-mediated dilation (10 times) were used most frequently. Twenty-seven studies had a cross-sectional design. CRP, IL-6 and sVCAM-1 were assessed most frequently. None of the immune markers were clearly associated with any of the surrogate CVD outcomes. No effect estimate could be calculated due to marked heterogeneity in study populations, immune markers, outcomes and statistical approaches.

Interpretation

This review could not identify a clear association between any of the immune markers and surrogate CVD outcomes. This may reflect a true lack of association, or may be explained by heterogeneity across studies and lack of follow-up data. Future research should focus on longitudinal studies measuring a select set of immune markers and surrogate CVD outcomes awaiting the primary outcome of clinical cardiovascular events.

Cardiovascular Complications of HIV Infection

HIV-infected individuals are at increased risk for cardiovascular events. Widely used cardiovascular disease (CVD) risk calculators to determine indications for statin treatment are not well validated for use in the HIV-infecte population. Some experts advocate including HIV infection as an independent risk factor for CVD. The effects of antiretroviral therapy on lipid profiles and the potentially increased risk for cardiovascular events must be taken into account when selecting treatment for HIV-infected individuals. There is increasing evidence that chronic immune activation and inflammation play a role in the pathogenesis of CVD in the context of HIV infection. This article summarizes a presentation by Marshall J. Glesby, MD, PhD, at the Ryan White HIV/AIDS Program Clinical Care Conference held in New Orleans, Louisiana, in December 2015.

Effects of atorvastatin on biomarkers of immune activation, inflammation, and lipids in virologically suppressed, human immunodeficiency virus-1-infected individuals with low-density lipoprotein cholesterol <130 mg/dL (AIDS Clinical Trials Group Study A5275)

BACKGROUND

Persistent immune activation and inflammation in virologically suppressed human immunodeficiency virus (HIV) infection are linked to excess cardiovascular risk.

OBJECTIVE

To evaluate atorvastatin as a strategy to reduce cardiovascular risk.

METHODS

A5275 was a multicenter, prospective, randomized, double-blind, placebo-controlled, cross-over pilot study of atorvastatin (10 mg/day for 4 weeks then 20 mg/day for 16 weeks) with a planned enrollment of 97 HIV-infected participants ≥18 years old, receiving boosted protease inhibitor-based antiretroviral therapy for ≥6 months, with plasma HIV-1 RNAs below limits of quantification ≥180 days, and fasting low-density lipoprotein (LDL) cholesterol ≥70 and <130 mg/dL. Primary endpoints were differences of changes ([week 44-week 24]-[week 20-baseline]) in CD4+ and CD8+ T-lymphocyte activation (% CD38+/DR+) and plasma levels of IL-6 and D-dimer. Arms were compared using the Wilcoxon rank-sum tests and also summarized changes pre-to-post atorvastatin treatment. Analyses were as-treated.

RESULTS

Ninety-eight participants were enrolled at 31 U S sites and 73 completed study treatment. Atorvastatin treatment did not decrease T-lymphocyte or monocyte activation, circulating biomarker levels (interleukin-6, D-dimer, soluble CD14, soluble CD163, monocyte chemoattractant protein-1, interferon-gamma-induced protein-10, high-sensitivity C-reactive protein, CD40L, and P-selectin) or white blood cell Krüppel-like Factor 2/4 messenger RNA levels. Pre-to-post atorvastatin reductions in calculated LDL (-38%), oxidized-LDL (-33%), and lipoprotein-associated phospholipase A2 (-31%) were significant (P < .01).

CONCLUSION

In virologically suppressed individuals with HIV infection, atorvastatin did not significantly decrease levels of soluble or cellular biomarkers of immune activation and inflammation but resulted in robust reductions in LDL cholesterol, oxLDL, and lipoprotein-associated phospholipase A2, biomarkers associated with cardiovascular risk.

Fatty liver is associated with an increased risk of diabetes and cardiovascular disease - Evidence from three different disease models: NAFLD, HCV and HIV

Fatty liver, which frequently coexists with necro-inflammatory and fibrotic changes, may occur in the setting of nonalcoholic fatty liver disease (NAFLD) and chronic infections due to either hepatitis C virus (HCV) or human immunodeficiency virus (HIV). These three pathologic conditions are associated with an increased prevalence and incidence of cardiovascular disease (CVD) and type 2 diabetes (T2D). In this multidisciplinary clinical review, we aim to discuss the ever-expanding wealth of clinical and epidemiological evidence supporting a key role of fatty liver in the development of T2D and CVD in patients with NAFLD and in those with HCV or HIV infections. For each of these three common diseases, the epidemiological features, pathophysiologic mechanisms and clinical implications of the presence of fatty liver in predicting the risk of incident T2D and CVD are examined in depth. Collectively, the data discussed in this updated review, which follows an innovative comparative approach, further reinforce the conclusion that the presence of fatty/inflamed/fibrotic liver might be a shared important determinant for the development of T2D and CVD in patients with NAFLD, HCV or HIV. This review may also open new avenues in the clinical and research arenas and paves the way for the planning of future, well-designed prospective and intervention studies.

Imaging High-Risk Atherosclerotic Plaques with PET

OPINION STATEMENT

Atherosclerotic disease, a primary cause of stroke and myocardial infarction, is the most common underlying cause of death worldwide. While atherosclerosis was formerly considered to be a relatively inert structural abnormality, decades of research have since shown that it is a biologically active process, driven by active inflammation. In concert with this conceptual shift, newer strategies to image vascular lesions have evolved. ¹⁸F-fluorodeoxyglucose (FDG) positron emission tomography (PET) imaging has been validated as a non-invasive tool to characterize atherosclerotic inflammation. It is hypothesized that a combination of structural and biological (e.g., inflammatory) imaging may provide better means to assess clinical risk, to assess efficacy of therapy, and to identify new, effective treatments. Limitations remain, however, and further advances in technology and tracer development are required before FDG PET imaging will contribute a significant clinical impact at the level of the individual patient.

Role of immune activation in progression to AIDS

PURPOSE OF REVIEW

The purpose is to review recent insights into the impact of HIV-associated immune activation on AIDS and non-AIDS morbidity and mortality.

RECENT FINDINGS

Immune activation has long been recognized as an important consequence of untreated HIV infection and predictor of AIDS progression, which declines but fails to normalize during suppressive antiretroviral therapy, and continues to predict disease in this setting. Thus, a major research agenda is to develop novel therapies to reduce persistent immune activation in treated HIV infection. Yet, the optimal targets for interventions remain unclear. Both the specific root causes of immune activation and the many interconnected pathways of immune activation that are most likely to drive disease risk in HIV-infected individuals remain incompletely characterized, but recent studies have shed new light on these topics.

SUMMARY

In the context of this review, we will summarize recent evidence helping to elucidate the immunologic pathways that appear most strongly predictive of infectious and noninfectious morbidity. We will also highlight the likelihood that not all root drivers of immune activation - and the discrete immunologic pathways to which they give rise - are likely to produce the same disease manifestations and/or be equally attenuated by early antiretroviral therapy initiation.

Immune activation and cardiovascular disease in chronic HIV infection

PURPOSE OF REVIEW

This article describes the potential contribution of immune activation in the pathogenesis of HIV-associated cardiovascular disease (CVD) - a leading cause of morbidity and mortality among HIV-positive persons with access to antiretroviral therapy (ART).

RECENT FINDINGS

We review recent literature that suggests abnormalities in both adaptive and innate immunity contributes to CVD risk among persons with HIV infection. In particular, potentially atherogenic T-cell mechanisms include persistent high-level T-cell activation (and associated proinflammatory mechanisms), as well as the presence of copathogens (e.g., cytomegalovirus) providing an ongoing stimulus for cytotoxic T-cell responses. More recent data have then emphasized the potential impact of monocyte-/macrophage-mediated inflammation and injury within atherosclerotic lesions. The abnormality driving innate immune activation many not fully reverse with antiretroviral therapy, highlighting the need for interventions that target inflammation as a CVD prevention strategy.

SUMMARY

Premature CVD among persons with HIV infection is due, in part, to persistent abnormalities in immune activation and systemic inflammation despite viral suppression. Prevention strategies for persons with HIV infection include those that target traditional CVD risk factors, as well as newer candidate treatments with potential immunomodulatory benefits.

Trends in Cardiovascular Disease Mortality Among Persons With HIV in New York City, 2001-2012

BACKGROUND

Cardiovascular disease (CVD) has become more prominent among human immunodeficiency virus (HIV)-infected individuals. The extent to which CVD mortality rates are changing is unclear.

METHODS

We analyzed surveillance data for all persons aged ≥13 years with HIV infection between 2001 and 2012 reported to the New York City HIV Surveillance Registry. We examined age-specific and age-standardized mortality rates due to major CVDs. We compared mortality time trends among persons with HIV with the general population, and examined differences among HIV-infected persons by RNA level.

RESULTS

There were 29 588 deaths reported among 145 845 HIV-infected persons. Ten percent of deaths were attributed to CVD as the underlying cause, including chronic ischemic heart disease (42% of CVD deaths), hypertensive diseases (27%), and cerebrovascular diseases (10%). While proportionate mortality due to CVD among persons with HIV increased (6% in 2001 to 15% in 2012, P < .001), the CVD mortality rate decreased from 5.1 to 2.7 per 1000 person-years. After controlling for sex, race/ethnicity, borough of residence, and year, those with HIV had significantly higher CVD mortality than the general population in all age groups through age 65. The CVD mortality rate was highest among viremic persons (adjusted rate ratio [RR], 3.53 [95% confidence interval {CI}, 3.21-3.87]) but still elevated among virally suppressed (<400 copies/mL) persons (adjusted RR, 1.53 [95% CI, 1.41-1.66]) compared with the general population.

CONCLUSIONS

Our findings support continued emphasis by HIV care providers on both viremic control and preventive measures including smoking cessation, blood pressure control, and lipid management.

Altered Monocyte and Endothelial Cell Adhesion Molecule Expression Is Linked to Vascular Inflammation in Human Immunodeficiency Virus Infection

BACKGROUND

Human immunodeficiency virus (HIV)-infected individuals have increased risk for vascular thrombosis, potentially driven by interactions between activated leukocytes and the endothelium.

METHODS

Monocyte subsets (CD14⁺CD16^-, CD14⁺CD16⁺, CD14^DimCD16⁺) from HIV negative (HIV^-) and antiretroviral therapy-treated HIV positive (HIV⁺) participants (N = 19 and 49) were analyzed by flow cytometry for adhesion molecule expression (lymphocyte function-associated antigen 1 [LFA-1], macrophage-1 antigen [Mac-1], CD11c/CD18, very late antigen [VLA]-4) and the fractalkine receptor (CX3CR1); these receptors recognize ligands (intercellular adhesion molecules [ICAMs], vascular cell adhesion molecule [VCAM]-1, fractalkine) on activated endothelial cells (ECs) and promote vascular migration. Plasma markers of monocyte (soluble [s]CD14, sCD163) and EC (VCAM-1, ICAM-1,2, fractalkine) activation and systemic (tumor necrosis factor receptor [TNFR-I], TNFR-II) and vascular (lipoprotein-associated phospholipase A₂ [Lp-PLA₂]) inflammation were measured by enzyme-linked immunosorbent assay.

RESULTS

Proportions of CD16⁺ monocyte subsets were increased in HIV⁺ participants. Among all monocyte subsets, levels of LFA-1 were increased and CX3CR1 levels were decreased in HIV⁺ participants (P < .01). Levels of sCD163, sCD14, fractalkine, ICAM-1, VCAM-1, TNFR-II, and Lp-PLA₂ were also increased in HIV⁺ participants (P < .05), and levels of sCD14, TNFR-I, and TNFR-II were directly related to ICAM-1 and VCAM-1 levels in HIV⁺ participants. Expression of CX3CR1 on monocyte subsets was inversely related to plasma Lp-PLA₂ (P < .05 for all).

CONCLUSIONS

Increased proportions of CD16⁺ monocytes, cells with altered adhesion molecule expression, combined with elevated levels of their ligands, may promote vascular inflammation in HIV infection.

Unstructured treatment interruption: an important risk factor for arterial stiffness in adult Malawian patients with antiretroviral treatment

OBJECTIVES

The aim of the study was to evaluate the impact of unstructured antiretroviral treatment (ART) interruption on arterial stiffness in adult Malawians who are on ART for at least 35 years.

DESIGN

The number of treatment interruption events for at least 60 days during ART treatment was quantified in patients for at least 35 years using retrospective routinely collected clinic data. Treatment interruption data were linked to patient carotid-femoral pulse wave velocity (PWV); PWV more than 10 m/s was set as the threshold for clinically significant cardiovascular disease risk.

METHODS

PWV was measured in patients (on ART ≥ 18 months), during routine ART clinic visits in Blantyre, Malawi, between November 2014 and July 2015. Multivariable linear regression was used to estimate the change in PWV m/s associated with treatment interruption. Multivariable logistic regression was used to estimate risk of PWV more than 10 m/s. All models were controlled for demographic and cardiometabolic risk factors.

RESULTS

In 220 patients (median age 45 years, range 37-80 years), 86 (37.4%) patients had at least one treatment interruption event. Median length of treatment interruption events was 75 days (range 31 days to 8 years). Overall, 31 (14%) patients had a PWV more than 10 m/s. In multivariable analysis, we found a 0.2 increase in PWV m/s per treatment interruption event (0.2, 95% confidence interval 0.1-0.4) and a two-fold increased risk of PWV more than 10 m/s per treatment interruption event (adjusted odds ratio 2.2, 95% confidence interval 1.2-4.0).

CONCLUSION

Treatment interruption in patients with ART for at least 35 years is a common and important risk factor for arterial stiffness. Therefore, the link between treatment interruption and cardiovascular disease in this setting in which traditional risks factors are less prevalent needs to be explored further.

GlycA Is a Novel Biomarker of Inflammation and Subclinical Cardiovascular Disease in Psoriasis

RATIONALE

GlycA, an emerging inflammatory biomarker, predicted cardiovascular events in population-based studies. Psoriasis, an inflammatory disease associated with increased cardiovascular risk, provides a model to study inflammatory biomarkers in cardiovascular disease (CVD). Whether GlycA associates with psoriasis and how it predicts subclinical CVD beyond high-sensitivity C-reactive protein in psoriasis is unknown.

OBJECTIVE

To investigate the relationships between GlycA and psoriasis and between GlycA and subclinical CVD.

METHODS AND RESULTS

Patients with psoriasis and controls (n=412) participated in a 2-stage study. We measured GlycA by nuclear magnetic resonance spectroscopy. National Institutes of Health (NIH) participants underwent 18-F Fluorodeoxyglucose Positron Emission Tomography Computed Tomography (18-FDG PET/CT) scans to assess vascular inflammation (VI) and coronary computed tomographic angiography to quantify coronary artery disease burden. Psoriasis cohorts were young (mean age=47.9), with low cardiovascular risk and moderate skin disease. high-sensitivity C-reactive protein and GlycA were increased in psoriasis compared with controls (GlycA: [PENN: 408.8±75.4 versus 289.4±60.2, P<0.0001; NIH: 415.8±63.2 versus 346.2±46, P<0.0001]) and demonstrated a dose-response with psoriasis severity. In stage 2, VI (β=0.36, P<0.001) and coronary artery disease (β=0.29, P=0.004) associated with GlycA beyond CV risk factors in psoriasis. In receiver operating characteristic analysis, GlycA added value in predicting VI (P=0.01) and coronary artery disease (P<0.01). Finally, initiating anti-tumor necrosis factor therapy (n=16) reduced psoriasis severity (P<0.001), GlycA (463.7±92.5 versus 370.1±78.5, P<0.001) and VI (1.93±0.36 versus 1.76±0.19, P<0.001), whereas GlycA remained associated with VI (β=0.56, P<0.001) post treatment.

CONCLUSIONS

GlycA associated with psoriasis severity and subclinical CVD beyond traditional CV risk and high-sensitivity C-reactive protein. Moreover, psoriasis treatment reduced GlycA and VI. These findings support the potential use of GlycA in subclinical CVD risk assessment in psoriasis and potentially other inflammatory diseases.

Rosuvastatin slows progression of subclinical atherosclerosis in patients with treated HIV infection

OBJECTIVE

To determine the effect of statins on the progression of subclinical atherosclerosis in a population of HIV-infected adults on antiretroviral therapy.

DESIGN

Double-blind, randomized clinical trial.

METHODS

Stopping Atherosclerosis and Treating Unhealthy Bone with RosuvastatiN in HIV infection was a 96-week double-blind, randomized clinical trial of 10 mg daily rosuvastatin (n = 72) vs. placebo (n = 75) in a population of HIV-infected subjects on stable antiretroviral therapy with LDL-cholesterol 130 mg/dl or less (≤3.36 mmol/l) and evidence of heightened T-cell activation (CD8CD38HLA-DR ≥19%) or increased inflammation [high sensitivity C-reactive protein ≥2 mg/l (≥19 mmol/l)]. Change in common carotid artery intima-media thickness (IMT) (CCA-IMT) was the primary outcome. Secondary outcomes were changes in LDL and coronary artery calcium.

RESULTS

Median (Q1, Q3) age was 46 (40, 53) years; 78% were man and 68% African-American; 49% were on a protease inhibitor. Mean (95% confidence interval) change in LDL was -21 (-27 to -15) mg/dl [-0.54 (-0.70 to -0.39) mmol/l] in the rosuvastatin arm. In a multivariable linear mixed-effects model, assignment to statin was associated with 0.019 mm (95% confidence interval: 0.002-0.037 mm) less progression of CCA-IMT over 96 weeks. We did not find substantial effect modification by level of inflammation or immune activation biomarkers, except for a borderline statistically significant interaction for soluble vascular cell adhesion molecule (P = 0.065). There was no difference in coronary artery calcium change (P = 0.61).

CONCLUSION

Rosuvastatin effectively lowers LDL and appears to substantially slow progression of CCA-IMT in patients with treated HIV infection. Future study is needed to determine whether subjects with higher levels of inflammation or immune activation derive greater cardiovascular benefit from statin therapy.

Cardiovascular Disease Risk Prediction in the HIV Outpatient Study

BACKGROUND

 Cardiovascular disease (CVD) risk prediction tools are often applied to populations beyond those in which they were designed when validated tools for specific subpopulations are unavailable.

METHODS

 Using data from 2283 human immunodeficiency virus (HIV)-infected adults aged ≥18 years, who were active in the HIV Outpatient Study (HOPS), we assessed performance of 3 commonly used CVD prediction models developed for general populations: Framingham general cardiovascular Risk Score (FRS), American College of Cardiology/American Heart Association Pooled Cohort equations (PCEs), and Systematic COronary Risk Evaluation (SCORE) high-risk equation, and 1 model developed in HIV-infected persons: the Data Collection on Adverse Effects of Anti-HIV Drugs (D:A:D) study equation. C-statistics assessed model discrimination and the ratio of expected to observed events (E/O) and Hosmer-Lemeshow χ² P value assessed calibration.

RESULTS

 From January 2002 through September 2013, 195 (8.5%) HOPS participants experienced an incident CVD event in 15 056 person-years. The FRS demonstrated moderate discrimination and was well calibrated (C-statistic: 0.66, E/O: 1.01, P = .89). The PCE and D:A:D risk equations demonstrated good discrimination but were less well calibrated (C-statistics: 0.71 and 0.72 and E/O: 0.88 and 0.80, respectively; P < .001 for both), whereas SCORE performed poorly (C-statistic: 0.59, E/O: 1.72; P = .48).

CONCLUSIONS

 Only the FRS accurately estimated risk of CVD events, while PCE and D:A:D underestimated risk. Although these models could potentially be used to rank US HIV-infected individuals at higher or lower risk for CVD, the models may fail to identify substantial numbers of HIV-infected persons with elevated CVD risk who could potentially benefit from additional medical treatment.

HIV, Cocaine Use, and Hepatitis C Virus: A Triad of Nontraditional Risk Factors for Subclinical Cardiovascular Disease

OBJECTIVE

We assessed cross-sectional and longitudinal associations of 3 nontraditional cardiovascular disease risk factors-HIV, cocaine use, and chronic hepatitis C virus infection-with 3 validated markers of subclinical cardiovascular disease: carotid artery plaque, albuminuria, and aortic pulse wave velocity in a well-characterized cohort.

APPROACH AND RESULTS

We measured carotid plaque at baseline and after 24 months, urine albumin/creatinine ratio every 6 months, and pulse wave velocity annually for up to 36 months in a predominantly black cohort of 292 participants (100 HIV negative and 192 HIV positive). Thirty-nine percent had chronic hepatitis C virus infection and 20%, 28%, and 52% were never, past, and current cocaine users, respectively. Sixteen percent, 47%, and 64% of those with none, 1 or 2, or all 3 nontraditional risk factors had ≥2 abnormal cardiovascular disease risk markers (P=0.001). In fully adjusted models that included all 3 nontraditional risk factors, HIV infection was independently associated with carotid plaque progression (increase in the number of anatomic segments with plaque), albuminuria (albumin-creatinine ratio >30 mg/g), albuminuria progression (doubling of albumin-creatinine ratio from baseline to a value >30 mg/g), and pulse wave velocity. Cocaine use was associated with an ≈3-fold higher odds of carotid plaque at baseline, and hepatitis C virus infection was significantly associated with a higher risk of carotid plaque progression.

CONCLUSIONS

These results suggest that HIV infection, cocaine use, and hepatitis C virus infection are important nontraditional risk factors for cardiovascular disease and highlight the need to understand the distinct and overlapping mechanisms of the associations.

Effects of Sodium Restriction on Activation of the Renin-Angiotensin-Aldosterone System and Immune Indices During HIV Infection

BACKGROUND

 Human immunodeficiency virus (HIV)-infected patients demonstrate increased activation of the renin-angiotensin-aldosterone system (RAAS). We evaluated changes in immune markers with physiological RAAS activation.

METHODS

 Immune activation markers were assessed serially in 18 HIV-infected and 7 non-HIV-infected subjects consuming an ad libitum diet followed by a standardized low-sodium diet.

RESULTS

 Levels of CCL-2 (P = .0004) and soluble CD163 (P = .0001) significantly increased with sodium restriction and RAAS activation, compared with levels in individuals with ad libitum sodium intake, among chronically treated HIV-infected subjects (mean duration of ART [±SEM], 11 ± 1 years), but not among non-HIV-infected subjects of similar age and sex.

CONCLUSIONS

 Dietary sodium restriction, which activates RAAS, uniquely stimulates critical indices of immune activation during HIV infection.

CLINICAL TRIALS REGISTRATION

 NCT01407237.

Non-human primate models of SIV infection and CNS neuropathology

Non-human primate models of AIDS and neuroAIDS are the premiere model of HIV infection of the CNS and neuropathogenesis. This review discusses current SIV infection models of neuroAIDS emphasizing findings in the last two years. Consistent in these findings is the interplay between host factors that regulate immune responses to virus and viral replication. Several rapid models of AIDS with consistent CNS pathogenesis exist, each of which modulates by antibody treatment or viruses that cause rapid immune suppression and replicate well in macrophages. Consistent in all of these models are data underscoring the importance of monocyte and macrophage activation, infection and accumulation in the CNS.

Ageing and inflammation in patients with HIV infection

Nowadays, HIV⁺ patients have an expected lifespan that is only slightly shorter than healthy individuals. For this reason, along with the fact that infection can be acquired at a relatively advanced age, the effects of ageing on HIV⁺ people have begun to be evident. Successful anti-viral treatment is, on one hand, responsible for the development of side effects related to drug toxicity; on the other hand, it is not able to inhibit the onset of several complications caused by persistent immune activation and chronic inflammation. Therefore, patients with a relatively advanced age, i.e. aged more than 50 years, can experience pathologies that affect much older citizens. HIV⁺ individuals with non-AIDS-related complications can thus come to the attention of clinicians because of the presence of neurocognitive disorders, cardiovascular diseases, metabolic syndrome, bone abnormalities and non-HIV-associated cancers. Chronic inflammation and immune activation, observed typically in elderly people and defined as 'inflammaging', can be present in HIV⁺ patients who experience a type of premature ageing, which affects the quality of life significantly. This relatively new condition is extremely complex, and important factors have been identified as well as the traditional behavioural risk factors, e.g. the toxicity of anti-retroviral treatments and the above-mentioned chronic inflammation leading to a functional decline and a vulnerability to injury or pathologies. Here, we discuss the role of inflammation and immune activation on the most important non-AIDS-related complications of chronic HIV infection, and the contribution of aging per se to this scenario.

Relationship Between Measures of Adiposity, Arterial Inflammation, and Subsequent Cardiovascular Events

BACKGROUND

The objective of this study was to evaluate how different measures of adiposity are related to both arterial inflammation and the risk of subsequent cardiovascular events.

METHODS AND RESULTS

We included individuals who underwent (18)F-fluorodeoxyglucose positron emission tomography/computed tomography imaging for oncological evaluation. Subcutaneous adipose tissue (SAT) volume, visceral adipose tissue (VAT) volume, and VAT/SAT ratio were determined. Additionally, body mass index, metabolic syndrome, and aortic (18)F-fluorodeoxyglucose uptake (a measure of arterial inflammation) were determined. Subsequent development of cardiovascular disease (CVD) events was adjudicated. The analysis included 415 patients with a median age of 55 (P25-P75: 45-65) and a median body mass index of 26.4 (P25-P75: 23.4-30.9) kg/m(2). VAT and SAT volume were significantly higher in obese individuals. VAT volume (r=0.290; P<0.001) and VAT/SAT ratio (r=0.208; P<0.001) were positively correlated with arterial inflammation. Thirty-two subjects experienced a CVD event during a median follow-up of 4 years. Cox proportional hazard models showed that VAT volume and VAT/SAT ratio were associated with CVD events (hazard ratio [95% confidence interval]: 1.15 [1.06-1.25]; P<0.001; 3.60 [1.88-6.92]; P<0.001, respectively). Body mass index, metabolic syndrome, and SAT were not predictive of CVD events.

CONCLUSIONS

Measures of visceral fat are positively related to arterial inflammation and are independent predictors of subsequent CVD events. Individuals with higher measures of visceral fat as well as elevated arterial inflammation are at highest risk for subsequent CVD events. The findings suggest that arterial inflammation may explain some of the CVD risk associated with adiposity.

Pathophysiology and management of cardiovascular disease in patients with HIV

Results from several studies have suggested that people with HIV have an increased risk of cardiovascular disease, especially coronary heart disease, compared with people not infected with HIV. People living with HIV have an increased prevalence of traditional cardiovascular disease risk factors, and HIV-specific mechanisms such as immune activation. Although older, more metabolically harmful antiretroviral regimens probably contributed to the risk of cardiovascular disease, new data suggest that early and continuous use of modern regimens, which might have fewer metabolic effects, minimises the risk of myocardial infarction by maintaining viral suppression and decreasing immune activation. Even with antiretroviral therapy, however, immune activation persists in people with HIV and could contribute to accelerated atherosclerosis, especially of coronary lesions that are susceptible to rupture. Therefore, treatments that safely reduce inflammation in people with HIV could provide additional cardiovascular protection alongside treatment of both traditional and non-traditional risk factors.