The Relationship Between Impaired Coronary Endothelial Function and Systemic Markers of Inflammation in People Living With HIV

The Association Between HIV-Related Stigma, ART Adherence, and Cardiovascular Disease Risk in People Living With HIV

INTRODUCTION

HIV/AIDS continues to be a significant health issue in sub-Saharan Africa, with stigma likely affecting ART adherence, and subsequently viremia, inflammation, and cardiovascular disease (CVD). We investigated the association between stigma, ART adherence, and CVD risk among people living with HIV (PLWH).

SETTING

A longitudinal study was conducted among 325 PLWH from the Ndlovu Cohort Study, South Africa.

METHODS

Stigma was assessed using a 12-item questionnaire (range: 0-44; higher scores indicate greater stigma). Pulse wave velocity (PWV, CVD surrogate marker) and viral load (VL) were assessed at 12 and 36 months. VL was considered a surrogate marker of ART adherence: VL > 1000 copies indicating poor/no adherence, VL 50-1000 copies suboptimal, and VL < 50 copies good adherence. The relationship between stigma, VL, and PWV was assessed by linear regression and changes in PWV overtime by mixed linear models.

RESULTS

At baseline, PLWH (n = 325, mean age (SD) = 41.1 (10.2) years, 67% female) had mean PWV of 7.3 min/s. Good, suboptimal, and poor adherence were 78%, 15%, and 7%, respectively. The mean (SD) stigma score was 16.9 (1.4) and was not associated with VL and PWV. Suboptimal and poor adherence were associated with higher PWV [beta = 4.18 (95% confidence interval (CI): 1.79 to 6.57)] at 12 months and between 12 and 36 months [beta = 1.30 (95% CI: 0.06 to 2.55)] in mixed model analyses in PLWH older than 49 years, respectively. PWV increased by 0.21 min/s (95% CI: 0.02 to 0.40; P = 0.03) between 12 and 36 months overall.

CONCLUSIONS

In this study, poor ART adherence was associated with higher PWV. The stigma score was low and not associated with ART adherence and PWV.

Immune Dysregulation in Ischemic Heart Disease Among Individuals with Human Immunodeficiency Virus

Individuals with human immunodeficiency virus (HIV) experience an elevated risk of ischemic heart disease and related cardiovascular sequelae. This is due to a combination of factors including traditional comorbidities, adverse effects of antiretroviral therapy, low-level viremia, viral coinfection, mucosal injury, and chronic immune activation and dysregulation. Understanding the underlying mechanisms, especially as they relate to inflammation, has implications for prevention, diagnostics, and therapeutics. This review highlights some of the foundational and recent literature on clinical phenotypes, diagnostic tools, and promising pharmacotherapies, along with future directions for translational research and clinical implementation.

Lipoprotein(a) Is Elevated and Inversely Related to Coronary Endothelial Function in People With HIV

BACKGROUND

HIV-associated cardiovascular disease (CVD) is increasing in prevalence. The mechanisms underlying the heightened cardiovascular risk faced by people with HIV (PWH), however, remain poorly defined. Recent studies indicate an important role of lipoprotein(a) (Lp[a]) in predicting CVD risk in the general population, but little is known regarding its role in HIV-associated CVD. Thus, we sought to evaluate whether Lp(a) is elevated in PWH and if it is associated with impaired coronary endothelial function (CEF), a known mediator of CVD in PWH.

METHODS AND RESULTS

In this cross-sectional study, cardiac magnetic resonance imaging with isometric handgrip exercise, an endothelial dependent stressor, was performed to assess CEF in 65 PWH and 52 controls without HIV. Percent changes in coronary cross-sectional area and coronary blood flow from rest to stress were used to quantify CEF. Lp(a) levels were assessed by immunoturbidimetric assay at the time of magnetic resonance imaging. Lp(a) levels were higher in PWH compared with controls (78 nmol/L [39-137 nmol/L] versus 45.5 nmol/L [18-102.5 nmol/L], P<0.01). Both percent change in coronary cross-sectional area (0.38% [-6.1% to 5.4%] versus 7.43% [2.4%-11.2%], P<0.0005) and coronary blood flow (9.1% [-1.3% to 23.1%] versus 24.1% [3.3%-39.8%], P<0.05) were lower in PWH compared with controls. In PWH, Lp(a) was inversely associated with percent change in coronary cross-sectional area (β=-6.18±1.01%/nmol/L, P<0.001) but not with percent change in coronary blood flow even after adjustment for confounding risk factors. No association between Lp(a) and measures of CEF was observed in individuals without HIV.

CONCLUSIONS

Lp(a) concentrations are elevated in PWH and inversely related to CEF in PWH.

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.

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

PURPOSE OF REVIEW

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

RECENT FINDINGS

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

SUMMARY

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