RAAS Activation Is Associated With Visceral Adiposity and Insulin Resistance Among HIV-infected Patients

HIV-Associated Hypertension: Risks, Mechanisms, and Knowledge Gaps

HIV type 1 (HIV-1) is the causative agent of AIDS. Since the start of the epidemic, HIV/AIDS has been responsible for ≈40 million deaths. Additionally, an estimated 39 million people are currently infected with the virus. HIV-1 primarily infects immune cells, such as CD4+ (cluster of differentiation 4+) T lymphocytes (T cells), and as a consequence, the number of CD4+ T cells progressively declines in people living with HIV. Within a span of ≈10 years, HIV-1 infection leads to the systemic failure of the immune system and progression to AIDS. Fortunately, potent antiviral therapy effectively controls HIV-1 infection and prevents AIDS-related deaths. The efficacy of the current antiviral therapy regimens has transformed the outcome of HIV/AIDS from a death sentence to a chronic disease with a prolonged lifespan of people living with HIV. However, antiviral therapy is not curative, is challenged by virus resistance, can be toxic, and, most importantly, requires lifelong adherence. Furthermore, the improved lifespan has resulted in an increased incidence of non-AIDS-related morbidities in people living with HIV including cardiovascular diseases, renal disease, liver disease, bone disease, cancer, and neurological conditions. In this review, we summarize the current state of knowledge of the cardiovascular comorbidities associated with HIV-1 infection, with a particular focus on hypertension. We also discuss the potential mechanisms known to drive HIV-1-associated hypertension and the knowledge gaps in our understanding of this comorbid condition. Finally, we suggest several directions of future research to better understand the factors, pathways, and mechanisms underlying HIV-1-associated hypertension in the post-antiviral therapy era.

Evaluation of New Hypertension Guidelines on the Prevalence and Control of Hypertension in a Clinical HIV Cohort: A Community-Based Study

The prevalence and control of hypertension (HTN) among people with HIV (PWH) have not been widely studied since the release of newer 2017 ACC/AHA guidelines ("new guidelines"). To address this research gap, we evaluated and compared the prevalence and control of HTN using both 2003 JNC 7 ("old guidelines") and new guidelines. We identified 3,206 PWH with HTN from the DC Cohort study in Washington, DC, between January 2018 and June 2019. We defined HTN using International Classification of Diseases (ICD)-9/-10 diagnosis codes for HTN or ≥2 blood pressure (BP) measurements obtained at least 1 month apart (>139/89 mm Hg per old or >129/79 mm Hg per new guidelines). We defined HTN control based on recent BP (≤129/≤79 mm Hg per new guidelines). We identified socio-demographics, cardiovascular risk factors, and co-morbidities associated with HTN control using multivariable logistic regression [adjusted odds ratio (aOR); 95% confidence interval (CI)]. The prevalence of HTN was 50.9% per old versus 62.2% per new guidelines. Of the 3,206 PWH with HTN, 887 (27.7%) had a recent BP ≤129/≤79 mm Hg, 1,196 (37.3%) had a BP 130-139/80-89 mm Hg, and 1,123 (35.0%) had a BP ≥140/≥90 mm Hg. After adjusting for socio-demographics, cardiovascular risk factors, and co-morbidities, factors associated with HTN control included age 60-69 (vs. <40) years (aOR: 1.42; 95% CI: 1.03-1.98), Hispanic (vs. non-Hispanic Black) race/ethnicity (aOR 1.49; 95% CI: 1.04-2.15), receipt of HIV care at a hospital-based (vs. community-based) clinic (aOR 1.21; 95% CI: 1.00-1.47), being unemployed (aOR 1.42; 95% CI: 1.11-1.83), and diabetes (aOR 1.35; 95% CI: 1.13-1.63). In a large urban cohort of PWH, nearly two-thirds had HTN and less than one-third of those met new guideline criteria. Our data suggest that more aggressive HTN control is warranted among PWH, with additional attention to younger patients and non-Hispanic Black patients.

Evolving mechanisms and presentations of cardiovascular disease in people with HIV: implications for management

People with HIV (PWH) are at elevated risk for cardiovascular diseases (CVDs), including myocardial infarction, heart failure, and sudden cardiac death, among other CVD manifestations. Chronic immune dysregulation resulting in persistent inflammation is common among PWH, particularly those with sustained viremia and impaired CD4+ T cell recovery. This inflammatory milieu is a major contributor to CVDs among PWH, in concert with common comorbidities (such as dyslipidemia and smoking) and, to a lesser extent, off-target effects of antiretroviral therapy. In this review, we discuss the clinical and mechanistic evidence surrounding heightened CVD risks among PWH, implications for specific CVD manifestations, and practical guidance for management in the setting of evolving data.

Adipose Tissue Dysfunction and Energy Balance Paradigms in People Living With HIV

Over the past 4 decades, the clinical care of people living with HIV (PLWH) evolved from treatment of acute opportunistic infections to the management of chronic, noncommunicable comorbidities. Concurrently, our understanding of adipose tissue function matured to acknowledge its important endocrine contributions to energy balance. PLWH experience changes in the mass and composition of adipose tissue depots before and after initiating antiretroviral therapy, including regional loss (lipoatrophy), gain (lipohypertrophy), or mixed lipodystrophy. These conditions may coexist with generalized obesity in PLWH and reflect disturbances of energy balance regulation caused by HIV persistence and antiretroviral therapy drugs. Adipocyte hypertrophy characterizes visceral and subcutaneous adipose tissue depot expansion, as well as ectopic lipid deposition that occurs diffusely in the liver, skeletal muscle, and heart. PLWH with excess visceral adipose tissue exhibit adipokine dysregulation coupled with increased insulin resistance, heightening their risk for cardiovascular disease above that of the HIV-negative population. However, conventional therapies are ineffective for the management of cardiometabolic risk in this patient population. Although the knowledge of complex cardiometabolic comorbidities in PLWH continues to expand, significant knowledge gaps remain. Ongoing studies aimed at understanding interorgan communication and energy balance provide insights into metabolic observations in PLWH and reveal potential therapeutic targets. Our review focuses on current knowledge and recent advances in HIV-associated adipose tissue dysfunction, highlights emerging adipokine paradigms, and describes critical mechanistic and clinical insights.

Mineralocorticoid Receptor Antagonism by Eplerenone and Arterial Inflammation in HIV: The MIRABELLA HIV Study

Importance

The risk for atherosclerotic disease is increased 1.5- to 2.0-fold among persons with HIV (PWH). Increased activation of the renin-angiotensin-aldosterone system may contribute to increased arterial inflammation in this population.

Objective

To determine the effects of eplerenone on arterial inflammation among well-treated PWH without known cardiovascular disease (CVD).

Design, Setting, and Participants

Well-treated PWH who participated in the double-blinded, placebo-controlled, Mineralocorticoid Receptor Antagonism for Cardiovascular Health in HIV (MIRACLE HIV) study between February 2017 and March 2022 assessing the effects of eplerenone on myocardial perfusion were invited to participate in the Mineralocorticoid Receptor Antagonism By Eplerenone to Lower Arterial Inflammation in HIV (MIRABELLA) substudy if there was no current statin use. Participants were enrolled in the MIRABELLA study and underwent additional 18F-fludeoxyglucose-positron emission tomography/computed tomography (18F-FDG PET/CT) imaging of the aorta and carotid arteries to assess arterial inflammation over 12 months of treatment with eplerenone vs placebo.

Interventions

Eplerenone, 50 mg, twice a day vs identical placebo.

Main Outcomes and Measures

The primary outcome was change in target to background ratio (TBR), a measure of arterial wall inflammation, in the index vessel after 12 months of treatment. The index vessel was defined as the vessel (aorta, left carotid artery, or right carotid artery) with the highest TBR at baseline in each participant.

Results

A total of 26 participants (mean [SD] age, 54 [7] years; 18 male [69%]) were enrolled in the study. Treatment groups (eplerenone, 13 vs placebo, 13) were of similar age, sex, and body mass index. Eplerenone was associated with a reduction in TBR of the primary end point, the index vessel (eplerenone vs placebo: model treatment effect, -0.31; 95% CI, -0.50 to -0.11; P = .006; percentage change, -12.4% [IQR, -21.9% to -2.6%] vs 5.1% [IQR, -1.6% to 11.0%]; P = .003). We further observed a significant reduction of the TBR of the most diseased segment (MDS) of the index vessel (eplerenone vs placebo: -19.1% [IQR, -27.0% to -11.9%] vs 6.8% [IQR, -9.1% to 12.1%]; P = .007). A similar result was seen assessing the index vessel of the carotids (eplerenone vs placebo: -10.0% [IQR, -21.8% to 3.6%] vs 9.7% [IQR, -9.8% to 15.9%]; P = .046). Reduction in the TBR of MDS of the index vessel on 18F-FDG PET/CT correlated with improvement in the stress myocardial blood flow on cardiac magnetic resonance imaging (Spearman ρ = -0.67; P = .01).

Conclusion and Relevance

In this small randomized clinical trial, eplerenone was associated with reduction in arterial inflammation among well-treated PWH without known CVD. In addition, reductions in arterial inflammation as measured by 18F-FDG PET/CT were related to improvements in stress myocardial perfusion. Further larger studies should explore whether eplerenone is a potential treatment strategy for inflammatory-mediated CVD in PWH.

Trial Registration

ClinicalTrials.gov Identifier: NCT02740179.

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.

Therapeutic potential of adiponectin in prediabetes: strategies, challenges, and future directions

Adiponectin, an adipose-derived hormone, plays a pivotal role in glucose regulation and lipid metabolism, with a decrease in circulating adiponectin levels being linked to insulin resistance and prediabetes. This review examines the therapeutic potential of adiponectin in managing prediabetes, elucidating on multiple aspects including its role in glucose and lipid metabolism, influence on insulin sensitivity, and anti-inflammatory properties. Moreover, the paper highlights the latest strategies to augment adiponectin levels, such as gene therapy, pharmacological interventions, dietary modifications, and lifestyle changes. It also addresses the challenges encountered in translating preclinical findings into clinical practice, primarily related to drug delivery, safety, and efficacy. Lastly, the review proposes future directions, underlining the need for large-scale human trials, novel adiponectin analogs, and personalized treatment strategies to harness adiponectin's full therapeutic potential in preventing the transition from prediabetes to diabetes.

Sleep-Disordered Breathing and Prevalent Hypertension in Men With and Without HIV

BACKGROUND

Sleep-disordered breathing (SDB) is a known risk factor for hypertension. Despite the well-established link between HIV infection and hypertension, it remains to be determined whether HIV infection modifies the association between SDB and hypertension.

SETTING

The Multicenter AIDS Cohort Study.

METHODS

SDB was assessed using in-home polysomnography in 779 men (436 with and 343 without HIV). The apnea-hypopnea index (AHI) based on oxyhemoglobin desaturation threshold of ≥3% or arousal (AHI 3a ) and ≥4% (AHI 4 ) along with oxygen desaturation index (ODI) were used to quantify SDB severity. Hypertension was defined as a blood pressure ≥140/90 mm Hg, use of antihypertensive medication, or self-report of a clinical diagnosis. The associations between HIV, SDB, and hypertension were characterized using multivariable logistic regression.

RESULTS

The prevalence of hypertension and SDB (AHI 3a ≥ 5 events/hr) was high, with estimates of 53.8% and 82.8%, respectively. Among men without SDB, HIV was independently associated with hypertension, with an adjusted odds ratio (OR) of 3.05 [95% confidence interval (CI): 1.33 to 7.01]. In men without HIV, SDB was associated with hypertension (OR: 2.93; 95% CI: 1.46 to 5.86). No significant increase in the odds of hypertension was noted in men with both HIV and SDB compared with men with either factor alone, with an OR of 3.24 (95% CI: 1.62 to 6.47). These results were consistent across different measures used to define SDB (AHI 3a , AHI 4 , ODI 3 , and ODI 4 ).

CONCLUSIONS

Predictors of hypertension differed by HIV status. SDB was associated with hypertension in men without HIV, but not in men with HIV. Among men with HIV, SDB did not affect the odds of hypertension.

The relationship between adipose tissue RAAS activity and the risk factors of prediabetes: a systematic review and meta-analysis

METHODS

This systematic review was developed in compliance with the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols (PRISMA-2020) standards. This was accomplished by searching clinical MeSH categories in MEDLINE with full texts, EMBASE, Web of Science, PubMed, Cochrane Library, Academic Search Complete, ICTRP and ClinicalTrial.gov. Reviewers examined all the findings and selected the studies that satisfied the inclusion criteria. The Downs and Black Checklist was used to assess for bias, followed by a Review Manager v5. A Forrest plot was used for the meta-analysis and sensitivity analysis. The protocol for this review was registered with PROSPERO CRD42022320252.

RESULTS

The clinical studies (n = 2) comprised 1065 patients with prediabetes and 1103 normal controls. The RAAS measurements were completed in the adipose tissue. The RAAS components, renin and aldosterone were higher in the prediabetic (PD) compared to the control [mean difference (MD) = 0.16, 95% CI 0.16 (-0.13, 0.45), p = 0.25]. Furthermore, the PD group demonstrated higher triglycerides mean difference [MD = 7.84, 95% CI 7.84 (-9.84, 25.51), p = 0.38] and increased BMI [MD = 0.13, 95% CI 0.13 (-0.74, 0.99), p = 0.77] compared to the control. The overall quality of the studies was fair with a median score and range of 17 (16-18).

CONCLUSION

The current study highlights the relationship between increased BMI, RAAS and insulin resistance which is a predictor of prediabetes. The renin is slightly higher in the prediabetes group without any statistical significance, aldosterone is rather negatively associated with prediabetes which may be attributed to the use of anti-hypertensive treatment.

Randomized Placebo-Controlled Trial to Evaluate Effects of Eplerenone on Myocardial Perfusion and Function Among Persons With Human Immunodeficiency Virus (HIV)-Results From the MIRACLE HIV Study

BACKGROUND

Increased renin angiotensin aldosterone system (RAAS) activity may contribute to excess cardiovascular disease in people with HIV (PWH). We investigated how RAAS blockade may improve myocardial perfusion, injury, and function among well-treated PWH.

METHODS

Forty PWH, on stable ART, without known heart disease were randomized to eplerenone 50 mg PO BID (n = 20) or identical placebo (n = 20) for 12 months. The primary endpoints were (1) myocardial perfusion assessed by coronary flow reserve (CFR) on cardiac PET or stress myocardial blood flow (sMBF) on cardiac MRI or (2) myocardial inflammation by extracellular mass index (ECMi) on cardiac MRI.

RESULTS

Beneficial effects on myocardial perfusion were seen for sMBF by cardiac MRI (mean [SD]: 0.09 [0.56] vs -0.53 [0.68] mL/min/g; P = .03) but not CFR by cardiac PET (0.01 [0.64] vs -0.07 [0.48]; P = .72, eplerenone vs placebo). Eplerenone improved parameters of myocardial function on cardiac MRI including left ventricular end diastolic volume (-13 [28] vs 10 [26] mL; P = .03) and global circumferential strain (GCS; median [interquartile range 25th-75th]: -1.3% [-2.9%-1.0%] vs 2.3% [-0.4%-4.1%]; P = .03), eplerenone versus placebo respectively. On cardiac MRI, improvement in sMBF related to improvement in global circumferential strain (ρ = -0.65, P = .057) among those treated with eplerenone. Selecting for those with impaired myocardial perfusion (CFR <2.5 and/or sMBF <1.8), there was a treatment effect of eplerenone versus placebo to improve CFR (0.28 [0.27] vs -0.05 [0.36]; P = .04). Eplerenone prevented a small increase in troponin (0.00 [-0.13-0.00] vs 0.00 [0.00-0.74] ng/L; P = .03) without effects on ECMi (0.9 [-2.3-4.3] vs -0.7 [-2.2--0.1] g/m2; P = .38). CD4+ T-cell count (127 [-38-286] vs -6 [-168-53] cells/μL; P = .02) increased in the eplerenone- versus placebo-treated groups.

CONCLUSIONS

RAAS blockade with eplerenone benefitted key indices and prevented worsening of myocardial perfusion, injury, and function among PWH with subclinical cardiac disease when compared with placebo.

CLINICAL TRIALS REGISTRATION

NCT02740179 (https://clinicaltrials.gov/ct2/show/NCT02740179?term=NCT02740179&draw=2&rank=1).

HIV and hypertension epidemiology

PURPOSE OF REVIEW

The aim of this study was to provide an overview of the burden, pathogenesis, and recent recommendations for treating hypertension among people living with HIV (PLWH). This review is relevant because of the increase in the prevalence of HIV as a chronic disease and the intersection of the increasing prevalence of hypertension.

RECENT FINDINGS

The contribution of HIV to the pathogenesis of hypertension is complex and still incompletely understood. Evidence suggests that chronic inflammation from HIV, antiretroviral treatment (ART), and comorbidities such as renal disease and insulin resistance contribute to developing hypertension in PLWH. Treatment is not distinct from guidelines for HIV-noninfected people. Nonpharmacological guidelines such as decreasing blood pressure by promoting a healthy lifestyle emphasizing exercise, weight loss, and smoking cessation are still recommended in the literature. The pharmacological management of hypertension in PLWH is similar, but special attention must be given to specific drugs with potential interaction with ART regimens. Further research is needed to investigate the pathways and effects of hypertension on HIV.

SUMMARY

There are different pathways to the pathogenesis of hypertension in PLWH. Clinicians should take it into consideration to provide more precise management of hypertension in PLWH. Further research into the subject is still required.

Association of different obesity patterns with hypertension in US male adults: a cross-sectional study

Obesity is an important risk factor for hypertension. We aimed to investigate the association between different obesity patterns and hypertension risk in a large male population in the US. Male participants from the National Health and Nutrition Examination Survey (NHANES) (2007-2018) were enrolled in this cross-sectional study. Social demographic information, lifestyle factors, anthropometric measurements and biochemical measurements were collected. Three obesity patterns were classified according to the body mass index (BMI) and waist circumference (WC), including overweight and general obesity, abdominal obesity, and compound obesity. We adopted multivariate logistic regression to investigate the associations between hypertension and different obesity patterns after adjusting for cofounding factors. Subgroup analysis, stratified by age, smoking, drinking and estimated glomerular filtration rate (eGFR), was also conducted to explore the associations between obesity patterns and hypertension risk among different populations. Moreover, the association between WC and hypertension among male individuals was also explored using restricted cubic spline (RCS) analysis. Receiver operating characteristic (ROC) was used to evaluate the discriminatory power of WC for screening hypertension risk. 13,859 male participants from NHANES survey (2007-2018) were enrolled. Comparing with the normal-weight group, the odds ratios (ORs) [95% confidence interval (CI)] for hypertension in individuals with overweight and general obesity, abdominal obesity and compound obesity were 1.41 [1.17-1.70], 1.97 [1.53-2.54] and 3.28 [2.70-3.99], respectively. Subgroup analysis showed that the effect of different obesity patterns on hypertension risk was highly stable among individuals with different clinical conditions. In addition, WC had a positive correlation with the risk of hypertension (OR: 1.43; 95% CI 1.37-1.52; P < 0.001) in fully adjusted multivariate logistic regression model. RCS analysis showed that the association between WC and hypertension risk was in a nonlinear pattern, and WC had a good discriminatory power for hypertension in ROC analysis. Different patterns of obesity have a great impact on the risk of hypertension among male individuals. Increment of WC significantly increased the hypertension risk. More attention should be paid to the prevention of obesity, especially abdominal obesity and compound obesity in male individuals.

Altered adolescents obesity metabolism is associated with hypertension: a UPLC-MS-based untargeted metabolomics study

Objective

This study aimed to explore the relationship between the plasma metabolites of adolescent obesity and hypertension and whether metabolite alterations had a mediating effort between adolescent obesity and hypertension.

Methods

We applied untargeted ultra-performance liquid chromatography-mass spectrometry (UPLC-MS) to detect the plasma metabolomic profiles of 105 adolescents. All participants were selected randomly based on a previous cross-sectional study. An orthogonal partial least squares- discriminant analysis (OPLS-DA), followed by univariate statistics and enrichment analysis, was used to identify differential metabolites. Using logistic regression for variable selection, an obesity-related metabolite score (OMS, OMS=∑k=1nβnmetabolite n) was constructed from the metabolites identified, and hypertension risk was estimated.

Results

In our study, based on P< 0.05, variable importance in projection (VIP) > 1.0, and impact value > 0.1, we identified a total of 12 differential metabolites. Significantly altered metabolic pathways were the sphingolipid metabolism, purine metabolism, pyrimidine metabolism, phospholipid metabolism, steroid hormone biosynthesis, tryptophan, tyrosine, and phenylalanine biosynthesis. The logistic regression selection resulted in a four-metabolite score (thymidine, sphingomyelin (SM) d40:1, 4-hydroxyestradiol, and L-lysinamide), which was positively associated with hypertension risk (odds ratio: 7.79; 95% confidence interval: 2.13, 28.47; for the quintile 4 compared with quartile 1 of OMS) after multivariable adjustment.

Conclusions

The OMS constructed from four differential metabolites was used to predict the risk of hypertension in adolescents. These findings could provide sensitive biomarkers for the early recognition of hypertension in adolescents with obesity.

Role of renin-angiotensin-aldosterone system activation and other metabolic variables in relation to arterial inflammation in HIV

BACKGROUND

Arterial inflammation remains increased among persons with HIV (PWH) compared with persons without HIV (PWOH) even when controlling for traditional risk factors. We sought to understand whether increased renin-angiotensin-aldosterone system (RAAS) activation may be related to arterial inflammation in PWH and when compared with PWOH.

DESIGN

Twenty PWH and 9 PWOH followed a controlled, standardized low and liberal sodium diet to simulate a RAAS-activated and RAAS-suppressed state, respectively. We measured serum lipoprotein-associated phospholipase A2 (LpPLA2) concentrations following both conditions to assess the physiologic dynamics of aldosterone in relation to arterial inflammation.

RESULTS

LpPLA2 levels were significantly higher among PWH versus PWOH during both the RAAS-activated state[5.3(4.2, 6.1) versus 4.0(3.0, 4.8)nmol/L, median(interquartile range),p = .01]) and RAAS-suppressed state[4.4(3.9, 5.3) versus 3.8(3.4, 4.1)nmol/L,p = .01]. Among PWH, but not PWOH, LpPLA2 increased significantly with RAAS activation(p = .03). LpPLA2 levels measured during the RAAS-suppressed state among PWH remained relatively higher than LpPLA2 levels under both conditions among PWOH. Log LpPLA2 was related to log aldosterone during the RAAS-activated state(r = .39,p = .04) among all participants. Log LpPLA2 was correlated with visceral fat(r = .46,p = .04) and log systolic blood pressure(r = .57,p = .009) during a RAAS-activated state when an increase in aldosterone was stimulated in HIV.

CONCLUSION

LpPLA2 is increased during a RAAS-activated state among PWH, but not among PWOH. Further, LpPLA2 was increased in both RAAS-activated and suppressed states in PWH compared with PWOH. These data suggest a biological link between increased aldosterone and arterial inflammation in this population. Future studies should test RAAS blockade on arterial inflammation as a targeted treatment approach in HIV.

Hypertension and human immunodeficiency virus: A paradigm for epithelial sodium channels?

Hypertension is a risk factor for end organ damage and death and is more common in persons with HIV compared to the general population. Several mechanisms have been studied in the pathogenesis of hypertension. Current evidence suggests that the epithelial sodium channel (ENaC) plays a key role in regulating blood pressure through the transport of sodium and water across membranes in the kidney tubules, resulting in retention of sodium and water and an altered fluid balance. However, there is scarcity of information that elucidates the role of ENaC in HIV as it relates to increasing the risk for development or pathogenesis of hypertension. This review summarized the evidence to date implicating a potential role for altered ENaC activity in contributing to hypertension in patients with HIV.

Emerging Viral Infections and the Potential Impact on Hypertension, Cardiovascular Disease, and Kidney Disease

Viruses are ubiquitous in the environment and continue to have a profound impact on human health and disease. The COVID-19 pandemic has highlighted this with impressive morbidity and mortality affecting the world's population. Importantly, the link between viruses and hypertension, cardiovascular disease, and kidney disease has resulted in a renewed focus and attention on this potential relationship. The virus responsible for COVID-19, SARS-CoV-2, has a direct link to one of the major enzymatic regulatory systems connected to blood pressure control and hypertension pathogenesis, the renin-angiotensin system. This is because the entry point for SARS-CoV-2 is the ACE2 (angiotensin-converting enzyme 2) protein. ACE2 is one of the main enzymes responsible for dampening the primary effector peptide Ang II (angiotensin II), metabolizing it to Ang-(1-7). A myriad of clinical questions has since emerged and are covered in this review. Several other viruses have been linked to hypertension, cardiovascular disease, and kidney health. Importantly, patients with high-risk apolipoprotein L1 (APOL1) alleles are at risk for developing the kidney lesion of collapsing glomerulopathy after viral infection. This review will highlight several emerging viruses and their potential unique tropisms for the kidney and cardiovascular system. We focus on SARS-CoV-2 as this body of literature in regards to cardiovascular disease has advanced significantly since the COVID-19 pandemic.

Expert Panel Review on Nonalcoholic Fatty Liver Disease in Persons With Human Immunodeficiency Virus

Nonalcoholic fatty liver disease (NAFLD) affects 25% of adults in the general population and is a disease spectrum ranging from steatosis to nonalcoholic steatohepatitis (NASH) to end-stage liver disease. NAFLD is an independent risk factor for cardiovascular disease, diabetes mellitus, and all-cause mortality, and NASH cirrhosis is a frequent indication for liver transplantation. In persons with human immunodeficiency virus (PWH), chronic liver disease is the second leading cause of non-human immunodeficiency virus-related mortality. Between 20% and 63% of PWH have NASH, and 14% to 63% have NASH with fibrosis. However, little is known about the optimal diagnostic strategies, risk factors for, and treatment of NAFLD in PWH. Here, we review current data on and identify knowledge gaps in the epidemiology, pathophysiology, diagnosis, and management of NAFLD in PWH and highlight priorities for research.

Pathophysiological Consequences of At-Risk Alcohol Use; Implications for Comorbidity Risk in Persons Living With Human Immunodeficiency Virus

At-risk alcohol use is a significant risk factor associated with multisystemic pathophysiological effects leading to multiorgan injury and contributing to 5.3% of all deaths worldwide. The alcohol-mediated cellular and molecular alterations are particularly salient in vulnerable populations, such as people living with HIV (PLWH), diminishing their physiological reserve, and accelerating the aging process. This review presents salient alcohol-associated mechanisms involved in exacerbation of cardiometabolic and neuropathological comorbidities and their implications in the context of HIV disease. The review integrates consideration of environmental factors, such as consumption of a Western diet and its interactions with alcohol-induced metabolic and neurocognitive dyshomeostasis. Major alcohol-mediated mechanisms that contribute to cardiometabolic comorbidity include impaired substrate utilization and storage, endothelial dysfunction, dysregulation of the renin-angiotensin-aldosterone system, and hypertension. Neuroinflammation and loss of neurotrophic support in vulnerable brain regions significantly contribute to alcohol-associated development of neurological deficits and alcohol use disorder risk. Collectively, evidence suggests that at-risk alcohol use exacerbates cardiometabolic and neurocognitive pathologies and accelerates biological aging leading to the development of geriatric comorbidities manifested as frailty in PLWH.

Evaluation of Mineralocorticoid Receptor Antagonism on Changes in NT-proBNP Among Persons With HIV

Subclinical myocardial dysfunction is prevalent among well-treated persons with HIV (PWH). We have previously demonstrated unique renin-angiotensin-aldosterone system physiology among PWH with metabolic dysregulation. Mineralocorticoid receptor blockade may be a targeted treatment strategy for subclinical heart disease in PWH. Forty-six PWH were randomized to receive either eplerenone 50 mg daily or placebo in a 6-month randomized, double-blinded, placebo-controlled trial. We assessed changes in N-terminal pro-B-type natriuretic peptide (NT-proBNP), a biomarker of cardiac stretch, under controlled posture and dietary conditions. The eplerenone- and placebo-treated groups demonstrated a long duration of HIV with good immunological control. NT-proBNP levels were similar between the groups at baseline (41.1 [20.2, 97.9] vs 48.9 [29.2, 65.4] ng/L, P = .80) and decreased significantly more in the eplerenone- vs placebo-treated groups after 6 months (change NT-proBNP -9.6 [-46.8, 0.3] vs -3.0 [-17.0, 39.9] ng/L, P = .02 for comparison of change between groups). Decreases in NT-proBNP were independent of changes in systolic and diastolic blood pressure, and related to decreases in high-sensitivity C-reactive protein (ρ = 0.32, P = .05) and inversely to increases in serum aldosterone (ρ = -0.33, P = .04) among all participants. Treatment with eplerenone for 6 months vs placebo significantly decreases NT-proBNP levels among PWH, independent of eplerenone’s known blood pressure-lowering effects. Further studies should elucidate whether lowering NT-proBNP in this at-risk metabolic population with subclinical heart disease will offer cardioprotection.

Association of renin and aldosterone with glucose metabolism in a Western European population: the KORA F4/FF4 study

INTRODUCTION

Primary aldosteronism is associated with impaired glucose tolerance. Whether plasma aldosterone and/or renin concentrations are associated with type 2 diabetes and continuous measures of glucose metabolism in the general population is still under debate.

RESEARCH DESIGN AND METHODS

The analyses included 2931 participants of the KORA F4 study at baseline and 2010 participants of the KORA FF4 study after a median follow-up of 6.5 years. The associations of active plasma renin and aldosterone concentrations with type 2 diabetes and continuous measures of glucose metabolism were assessed using logistic and linear regression models. Results were adjusted for sex, age, body mass index (BMI), estimated glomerular filtration rate, potassium, use of ACE inhibitors, angiotensin receptor blockers, beta blockers, diuretics and calcium channel blockers.

RESULTS

Cross-sectionally, renin was associated with type 2 diabetes (OR per SD: 1.25, 95% CI 1.10 to 1.43, p<0.001), fasting glucose, 2-hour glucose, insulin, proinsulin, HOMA-B (homeostasis model assessment of beta cell function) and HOMA-IR (homeostasis model assessment of insulin resistance) (all p values <0.001). Aldosterone was not associated with type 2 diabetes (OR: 1.04, 95% CI 0.91 to 1.19; p=0.547) but with insulin, proinsulin and HOMA-IR (all p values <0.001). The aldosterone-renin ratio was inversely associated with type 2 diabetes and several measures of glucose metabolism. Longitudinally, neither renin (OR: 1.12, 95% CI 0.92 to 1.36) nor aldosterone (OR: 0.91, 95% CI 0.74 to 1.11) were associated with incident type 2 diabetes. Renin was inversely associated with changes of insulin concentrations.

CONCLUSIONS

In the KORA F4/FF4 study, renin and aldosterone were not associated with incident type 2 diabetes and largely unrelated to changes of measures of glucose metabolism. Cross-sectionally, aldosterone was associated with surrogate parameters of insulin resistance. However, these associations were not independent of renin.

Coronary Vasculature and Myocardial Structure in HIV: Physiologic Insights From the Renin-Angiotensin-Aldosterone System

The landscape of HIV medicine dramatically changed with the advent of contemporary antiretroviral therapies, which has allowed persons with HIV (PWH) to achieve good virologic control, essentially eliminating HIV-related complications and increasing life expectancy. As PWH are living longer, noncommunicable diseases, such as cardiovascular disease (CVD), have become a leading cause of morbidity and mortality in PWH with rates that are 50% to 100% higher than in well-matched persons without HIV. In this review, we focus on disease of the coronary microvasculature and myocardium in HIV. We highlight a key hormonal system important to cardiovascular endocrinology, the renin-angiotensin-aldosterone system (RAAS), as a potential mediator of inflammatory driven-vascular and myocardial injury and consider RAAS blockade as a physiologically targeted strategy to reduce CVD in HIV.

Current Considerations for Clinical Management and Care of People with HIV: Findings from the 11th Annual International HIV and Aging Workshop

The number of people with HIV (PWH) aged 50 years or older continues to steadily increase. The convergence of age- and HIV-related complications in these individuals presents a challenge for both patients and clinicians alike. New findings continue to emerge, as numerous researchers evaluate the combined impact of these two factors on quality of life, physiological systems, and mental health in PWH. Since its first occurrence in 2009, the International Workshop on HIV and Aging has served as a multidisciplinary meeting to share basic biomedical data, clinical trial results, treatment strategies, and epidemiological recommendations, toward better understanding and outcomes among like-minded scientific professionals. In this article, we share a selection of key findings presented in plenary talks at the 11th Annual International Workshop on HIV and Aging, held virtually from September 30, 2020 to October 2, 2020. We will also address the future directions of HIV and aging research, to further assess how the aging process intersects with chronic HIV.

HIV Associated Preeclampsia: A Multifactorial Appraisal

Introduction: This review explores angiogenesis, vascular dysfunction, the complement system, RAAS, apoptosis and NETosis as potential pathways that are dysregulated during preeclampsia, HIV infection and ART usage. Results: HIV-1 accessory and matrix proteins are protagonists for the elevation of oxidative stress, apoptosis, angiogenesis, and elevation of adhesion markers. Despite the immunodeficiency during HIV-1 infection, HIV-1 exploits our cellular defence arsenal by escaping cell-mediated lysis, yet HIV-1 infectivity is enhanced via C5a release of TNF-α and IL-6. This review demonstrates that PE is an oxidatively stressed microenvironment associated with increased apoptosis and NETosis, but with a decline in angiogenesis. Immune reconstitution in the duality of HIV-1 and PE by protease inhibitors, HAART and nucleoside reverse transcriptase, affect similar cellular pathways that eventuate in loss of endothelial cell integrity and, hence, its dysfunction. Conclusions: HIV-1 infection, preeclampsia and ARTs differentially affect endothelial cell function. In the synergy of both conditions, endothelial dysfunction predominates. This knowledge will help us to understand the effect of HIV infection and ART on immune reconstitution in preeclampsia.

Chronic binge alcohol and ovariectomy dysregulate omental adipose tissue metaboproteome in simian immunodeficiency virus-infected female macaques

Effective antiretroviral therapy (ART) has significantly reduced mortality of people living with HIV (PLWH), and the prevalence of at-risk alcohol use is higher among PLWH. Increased survival and aging of PLWH is associated with increased prevalence of metabolic comorbidities especially among menopausal women, and adipose tissue metabolic dysregulation may be a significant contributing factor. We examined the differential effects of chronic binge alcohol (CBA) administration and ovariectomy (OVX) on the omental adipose tissue (OmAT) proteome in a subset of simian immunodeficiency virus (SIV)-infected macaques of a longitudinal parent study. Quantitative discovery-based proteomics identified 1,429 differentially expressed proteins. Ingenuity Pathway Analysis (IPA) was used to calculate z-scores, or activation predictions, for functional pathways and diseases. Results revealed that protein changes associated with functional pathways centered around the "OmAT metaboproteome profile." Based on z-scores, CBA did not affect functional pathways of metabolic disease but dysregulated proteins involved in adenosine monophosphate-activated protein kinase (AMPK) signaling and lipid metabolism. OVX-mediated proteome changes were predicted to promote pathways involved in glucose- and lipid-associated metabolic disease. Proteins involved in apoptosis, necrosis, and reactive oxygen species (ROS) pathways were also predicted to be activated by OVX and these were predicted to be inhibited by CBA. These results provide evidence for the role of ovarian hormone loss in mediating OmAT metaboproteome dysregulation in SIV and suggest that CBA modifies OVX-associated changes. In the context of OVX, CBA administration produced larger metabolic and cellular effects, which we speculate may reflect a protective role of estrogen against CBA-mediated adipose tissue injury in female SIV-infected macaques.

Contribution of Adipose Tissue to the Chronic Immune Activation and Inflammation Associated With HIV Infection and Its Treatment

White adipose tissue (AT) contributes significantly to inflammation – especially in the context of obesity. Several of AT’s intrinsic features favor its key role in local and systemic inflammation: (i) large distribution throughout the body, (ii) major endocrine activity, and (iii) presence of metabolic and immune cells in close proximity. In obesity, the concomitant pro-inflammatory signals produced by immune cells, adipocytes and adipose stem cells help to drive local inflammation in a vicious circle. Although the secretion of adipokines by AT is a prime contributor to systemic inflammation, the lipotoxicity associated with AT dysfunction might also be involved and could affect distant organs. In HIV-infected patients, the AT is targeted by both HIV infection and antiretroviral therapy (ART). During the primary phase of infection, the virus targets AT directly (by infecting AT CD4 T cells) and indirectly (via viral protein release, inflammatory signals, and gut disruption). The initiation of ART drastically changes the picture: ART reduces viral load, restores (at least partially) the CD4 T cell count, and dampens inflammatory processes on the whole-body level but also within the AT. However, ART induces AT dysfunction and metabolic side effects, which are highly dependent on the individual molecules and the combination used. First generation thymidine reverse transcriptase inhibitors predominantly target mitochondrial DNA and induce oxidative stress and adipocyte death. Protease inhibitors predominantly affect metabolic pathways (affecting adipogenesis and adipocyte homeostasis) resulting in insulin resistance. Recently marketed integrase strand transfer inhibitors induce both adipocyte adipogenesis, hypertrophy and fibrosis. It is challenging to distinguish between the respective effects of viral persistence, persistent immune defects and ART toxicity on the inflammatory profile present in ART-controlled HIV-infected patients. The host metabolic status, the size of the pre-established viral reservoir, the quality of the immune restoration, and the natural ageing with associated comorbidities may mitigate and/or reinforce the contribution of antiretrovirals (ARVs) toxicity to the development of low-grade inflammation in HIV-infected patients. Protecting AT functions appears highly relevant in ART-controlled HIV-infected patients. It requires lifestyle habits improvement in the absence of effective anti-inflammatory treatment. Besides, reducing ART toxicities remains a crucial therapeutic goal.

Mechanisms and primary prevention of atherosclerotic cardiovascular disease among people living with HIV

PURPOSE OF REVIEW

To highlight mechanisms of elevated risk of atherosclerotic cardiovascular disease (ASCVD) among people living with HIV (PLWH), discuss therapeutic strategies, and opportunities for primary prevention.

RECENT FINDINGS

HIV-associated ASCVD risk is likely multifactorial and due to HIV-specific factors and traditional risk factors even in the setting of treated and suppressed HIV disease. Although a growing body of evidence suggests that inflammation and immune activation are key drivers of atherogenesis, therapies designed to lower inflammation including colchicine and low-dose methotrexate have not improved secondary cardiovascular endpoints among PLWH. Statins continue to be the mainstay of management of hyperlipidemia in HIV, but the impact of newer lipid therapies including proprotein convertase subtilisin/kexin type 9 inhibitors on ASCVD risk among PLWH is under investigation. Aside from the factors mentioned above, healthcare disparities are particularly prominent among PLWH and thus likely contribute to increased ASCVD risk.

SUMMARY

Our understanding of mechanisms of elevated ASCVD risk in HIV continues to evolve, and the optimal treatment for CVD in HIV aside from targeting traditional risk factors remains unknown. Future studies including novel therapies to lower inflammation, control of risk factors, and implementation science are needed to ascertain optimal ways to treat and prevent ASCVD among PLWH.

A Narrative Review of the Renin-Angiotensin-Aldosterone System in the Placenta and Placental Bed of HIV Infected Women of African Ancestry with Preeclampsia

PURPOSE OF REVIEW

Both HIV infection and preeclampsia (PE), a pregnancy-specific disorder of hypertension and multi-system organ involvement, have high prevalence rates especially in low-to-middle-income countries. The immunoexpression of specific renin-angiotensin-aldosterone system (RAAS) receptors in the placenta and placental bed interface may forecast the risk of PE.

RECENT FINDINGS

Preeclampsia is a leading risk factor for mortality worldwide and remains a challenge in HIV-infected individuals especially those on antiretroviral therapy (ART). Irregular RAAS stimulation may be linked to the pathophysiology of hypertension in HIV infection and in PE. The AT1 receptor is expressed across all trimesters of pregnancy, within placental tissue, eliciting vasoconstriction. This increased expression is associated with the severity of PE, implying that the increased expression may be involved in the pathogenesis of this pregnancy disorder. The AT2 receptor expression in normotensive pregnancies was shown to be lower as compared to non-pregnant individuals. Furthermore, in the PE placental bed, the AT2 receptor is the predominant receptor subtype and is found in extravillous trophoblast cells where they facilitate vasodilation. However, AT4R in placentae of PE pregnancies are found to be significantly reduced compared to normotensives pregnancies. The data on the role played by the RAAS pathway in pregnancy is conflicting. Investigation into a tissue-based RAAS with emphasis on immune-expression within the placenta and placental bed may help resolve this conundrum.

General and abdominal obesity and incident hypertension among people living with HIV on antiretroviral therapy

Hypertension is highly prevalent among people living with HIV (PLWH). We sought to characterize the hypertension incidence among PLWH on antiretroviral therapy, focusing on the effect of change in general and abdominal obesity on hypertension during follow-up. This was a prospective analysis of 229 treated PLWH aged over 40 years without hypertension at baseline. Overall a median follow-up of 2.9 years, 26.2% PLWH developed hypertension. In multivariable models, compared to those without obesity measures at both baseline and follow-up visit, PLWH with general obesity at both occasions (adjusted odds ratio [aOR] = 3.83, P = 0.006) or at baseline only (aOR = 5.45, P = 0.003), abdominal obesity (measured as waist circumference) at both occasions (aOR = 3.87, P = 0.001) or at follow-up only (aOR = 2.27; 9P = 0.060), abdominal obesity (measured as waist-to-hip ratio) at both occasions (aOR = 2.27, P = 0.077) were at increased risk of incident hypertension. Our data show that both general and abdominal obesity especially in the persistent status increase the hypertension risk in treated PLWH.

Duration of antiretroviral therapy among people living with HIV and incidence of hypertension in Ghana

Understanding the differential rates of incident hypertension among People Living with HIV (PLWH) based of duration of exposure to combination antiretroviral therapy (cART) may provide insights into the pathogenesis of hypertension in this population. Utilizing the dataset of a prospective study conducted at a Ghanaian tertiary medical center, we evaluated factors associated with incident hypertension among PLWH previously naïve to cART before study enrollment (cART newly prescribed group, n = 221) versus PLWH established on cART for at least a year (cART established group, n = 212). New-onset hypertension was diagnosed as clinic BP > 140/90 mmHg on two separate clinic visits over 12-month follow-up. Cox proportional hazards regression models were used to assess factors associated with incident hypertension. Mean age of new versus cART established was 41.1 ± 8.2 versus 45.1 ± 8.6 years (p < .001), with more women in the cART established group (68.3 vs. 82%, p = .0009). There were 105 (24.3%) episodes of incident hypertension over 328 person-years follow-up (PYFU), incidence rate of 320.1 (95% CI: 263.1-385.9)/1000 PYFU, with higher rates in new versus cART established (476.6/1000 PYFU vs. 222.8/1000 PYFU, p = 0.0002). Overall, age by increasing decile (aHR 0.76; 95% CI: 0.59-0.98), log HIV-1 viral load (aHR 1.16; 1.04-1.35), and use of tenofovir (aHR 1.66; 1.04-2.64) were associated with incident hypertension. While CD4 counts, age, BMI, pre-diabetes, and urban/peri-urban residency were independently associated with hypertension in the cART established group; no independent predictors were identified among the cART newly prescribed group. Further studies to explore the potential mechanisms underlying incidence of hypertension in PLWH are warranted.

Hypertension and Metabolic Syndrome in Persons with HIV

PURPOSE OF REVIEW

With the advent of highly active antiretroviral therapy (ART), the life span of persons with HIV (PWH) has been nearly normalized. With aging, prevalence of the metabolic syndrome (MetS), including hypertension, has increased in the HIV population and exceeds that in the general population in some studies. This is due to a combination of traditional risk factors in addition to the effects attributable to the virus and ART. We review recent findings on the mechanisms contributing to MetS and hypertension in PWH, particularly those specific to the viral infection and to ART.

RECENT FINDINGS

Activation of the renin-angiotensin-aldosterone system (RAAS) and chronic immune activation contribute to the development of MetS and hypertension in PWH. HIV proteins and some ART agents alter adipocyte health contributing to dyslipidemias, weight gain, and insulin resistance. HIV infection also contributes to hypertension by direct effects on the RAAS that intertwine with inflammation by the RAAS also contributing to T cell activation. Recent data suggest that in addition to current ART, therapeutic targeting of the MetS and hypertension in PWH, by interfering with the RAAS, treating insulin resistance directly or by use of immunomodulators that dampen inflammation, may be critical for preventing or treating these risk factors and to improve overall cardiovascular complications in the HIV-infected aging population.

IL (Interleukin)-1 Receptor Antagonist Increases Ang (Angiotensin [1–7]) and Decreases Blood Pressure in Obese Individuals

IL (Interleukin)-1 antagonism decreases blood pressure in obese individuals. The underlying mechanisms are unknown. Based on experimental data, we hypothesized an effect of IL-1 antagonism via modulation of the renin-angiotensin-aldosterone system. In this explorative study, we examined shorter- (2 days) and longer-term effects (4 weeks) of IL-1 antagonism (anakinra/Kineret) on renin-angiotensin system peptide profiles and on hemodynamic parameters assessed by noninvasive measurement in obese (body mass index ≥30 kg/m 2 ) individuals from 2 interventional trials (a prospective interventional trial [n=73] and a placebo controlled-double blinded interventional trial [n=67]). A total of 140 patients were included. Systolic blood pressure decreased after short-term (absolute difference −5.2 mm Hg [95% CI, −8.5 to −1.8]; P =0.0006) and after longer-term treatment with anakinra (absolute difference −3.9 mm Hg [95% CI, −7.59 to −0.21]; P =0.04), with no change in blood pressure in the placebo group. Upon IL-1 antagonism, equilibrium levels of Ang II (angiotensin II), Ang I, aldosterone, and renin remained unchanged. In contrast, Ang (1–7) peptide levels increased after 4 weeks (between-group difference 16.35 pmol/L [95% CI, 1.22–30.17], P =0.03), as well as the Ang (1–7)/Ang II ratio (between-group difference 0.42 [95% CI, 0.17–0.67], P =0.02) in comparison to placebo. Consistently, the stroke systemic vascular resistance index significantly decreased in the anakinra group (between-group difference of −62.65 dyn/sec per cm −5 per m 2 [95% CI, −116.94 to −18.36], P =0.008, consistent with a 25% decrease). IL-1 antagonism increased the vasodilatory Ang (1–7) peptide after 4 weeks of treatment in obese individuals, paralleled by a decrease in peripheral vascular resistance. These findings point to an IL-1 mediated blood pressure-lowering mechanism via modulation of Ang (1–7).

Registration—

URL: https://www.clinicaltrials.gov . Unique identifiers: NCT02227420 and NCT02672592.

Serum Lipocalin 2 (Neutrophil Gelatinase-Associated Lipocalin) in Relation to Biomarkers of Inflammation and Cardiac Stretch During Activation of the Renin-Angiotensin-Aldosterone System in Human Immunodeficiency Virus

PURPOSE

To evaluate the relationship of lipocalin 2 to inflammation and cardiac injury with increased aldosterone in human immunodeficiency virus (HIV).

METHODS

A standardized 6-day low-sodium diet was used to stimulate renin-angiotensin-aldosterone system (RAAS) activation, and serum lipocalin 2 and biomarkers of inflammation and cardiac stretch were assessed among persons with or without HIV.

RESULTS

Lipocalin 2 levels increased with RAAS activation compared with suppression in the HIV group (median level [interquartile range], 71.3 [59.2-99.7] vs 67.0 [51.8-86.3] ng/mL; P = .01). During RAAS activation, lipocalin 2 was related to biomarkers of inflammation (tumor necrosis factor α [P = .007]), monocyte/macrophage activation (soluble CD163 [P = .005] and chemokine [C-C motif] ligand 2 [P = .03]), and markers of cardiac stretch (brain natriuretic peptide [P < .001] and N-terminal fragment of the prohormone brain natriuretic peptide [P = .001]) in HIV.

CONCLUSION

Lipocalin 2 may be important in modulating aldosterone-induced inflammation, monocyte activation, and cardiac stretch during RAAS activation in HIV.

CLINICAL TRIAL REGISTRATION

NCT01407237.

Obesity and Fat Metabolism in Human Immunodeficiency Virus-Infected Individuals: Immunopathogenic Mechanisms and Clinical Implications

Metabolic complications relating to complex effects of viral and immune-mediated mechanisms are now a focus of clinical care among persons living with human immunodeficiency virus (PLHIV), and obesity is emerging as a critical problem. To address knowledge gaps, the US National Institutes of Health sponsored a symposium in May 2018 entitled "Obesity and Fat Metabolism in HIV-infected Individuals." Mechanisms relating to adipose dysfunction and fibrosis, immune function, inflammation, and gastrointestinal integrity were highlighted as contributors to obesity among PLHIV. Fibrotic subcutaneous adipose tissue is metabolically dysfunctional and loses its capacity to expand, leading to fat redistribution, including visceral obesity and ectopic fat accumulation, promoting insulin resistance. Viral proteins, including viral protein R and negative regulatory factor, have effects on adipogenic pathways and cellular metabolism in resident macrophages and T cells. HIV also affects immune cell trafficking into the adipose compartments, with effects on adipogenesis, lipolysis, and ectopic fat accumulation. Key cellular metabolic functions are likely to be affected in PLHIV by gut-derived cytokines and altered microbiota. There are limited strategies to reduce obesity specifically in PLHIV. Enhancing our understanding of critical pathogenic mechanisms will enable the development of novel therapeutics that may normalize adipose tissue function and distribution, reduce inflammation, and improve insulin sensitivity in PLHIV.

Characteristics, Prevention, and Management of Cardiovascular Disease in People Living With HIV: A Scientific Statement From the American Heart Association

As early and effective antiretroviral therapy has become more widespread, HIV has transitioned from a progressive, fatal disease to a chronic, manageable disease marked by elevated risk of chronic comorbid diseases, including cardiovascular diseases (CVDs). Rates of myocardial infarction, heart failure, stroke, and other CVD manifestations, including pulmonary hypertension and sudden cardiac death, are significantly higher for people living with HIV than for uninfected control subjects, even in the setting of HIV viral suppression with effective antiretroviral therapy. These elevated risks generally persist after demographic and clinical risk factors are accounted for and may be partly attributed to chronic inflammation and immune dysregulation. Data on long-term CVD outcomes in HIV are limited by the relatively recent epidemiological transition of HIV to a chronic disease. Therefore, our understanding of CVD pathogenesis, prevention, and treatment in HIV relies on large observational studies, randomized controlled trials of HIV therapies that are underpowered to detect CVD end points, and small interventional studies examining surrogate CVD end points. The purpose of this document is to provide a thorough review of the existing evidence on HIV-associated CVD, in particular atherosclerotic CVD (including myocardial infarction and stroke) and heart failure, as well as pragmatic recommendations on how to approach CVD prevention and treatment in HIV in the absence of large-scale randomized controlled trial data. This statement is intended for clinicians caring for people with HIV, individuals living with HIV, and clinical and translational researchers interested in HIV-associated CVD.

Factors Associated With Insulin Resistance in Adults With HIV Receiving Contemporary Antiretroviral Therapy: a Brief Update

PURPOSE OF REVIEW

This narrative review summarizes recent data on factors associated with insulin resistance (IR) in adults with HIV, including contemporary antiretroviral therapy (ART).

RECENT FINDINGS

IR remains common in persons with HIV, even those receiving contemporary ART. Generalized and abdominal obesity and ectopic fat are correlates of IR, and emerging data have identified associations with biomarkers of inflammation and immune activation. Small studies suggest associations between mitochondria and IR. In ART-naïve individuals, IR increased within 4 weeks of starting ART in persons receiving contemporary boosted protease inhibitors or an integrase inhibitor. The importance of IR in non-diabetic persons with HIV will continue to grow as the population ages and obesity increases. Non-invasive estimates of IR appear to perform well in persons with HIV, but clinically relevant cutoffs are uncertain. Unexpected metabolic effects of newer HIV integrase inhibitors have been reported; thus, careful observation for and studies of IR are still warranted.

Prior exposure to thymidine analogs and didanosine is associated with long-lasting alterations in adipose tissue distribution and cardiovascular risk factors

BACKGROUND

Thymidine analogs and didanosine (ddI) have been associated with redistribution of body fat from subcutaneous adipose tissue (SAT) to visceral adipose tissue (VAT), which, in turn, is a risk factor for cardiovascular disease. We explored differences in adipose tissue distribution between people living with HIV (PLWH) with prior exposure to thymidine analogs and/or ddI, without exposure, and uninfected controls and the association with cardiovascular disease risk factors.

METHODS

In all, 761 PLWH from the Copenhagen Comorbidity in HIV Infection study, and 2283 age and sex-matched uninfected controls from the Copenhagen General Population Study were included. PLWH were stratified according to prior exposure to thymidine analogs and/or ddI. VAT and SAT were determined by abdominal computed tomography scan. Hypotheses were tested using regression analyses.

RESULTS

Exposure to thymidine analogs and/or ddI was associated with 21.6 cm larger VAT (13.8-29.3) compared to HIV infection without exposure. HIV-negative status was associated with similar VAT compared to HIV infection without exposure. Cumulative exposure to thymidine analogs and/or ddI [3.7 cm per year (2.3-5.1)], but not time since discontinuation [-1.1 cm per year (-3.4 to 1.1)], was associated with VAT. Prior exposure to thymidine analogs and/or ddI was associated with excess risk of hypertension [adjusted odds ratio (aOR) 1.62 (1.13-2.31)], hypercholesterolemia [aOR 1.49 (1.06-2.11)], and low high-density lipoprotein [aOR 1.40 (0.99-1.99)].

CONCLUSIONS

This study suggests a potentially irreversible and harmful association of thymidine analogs and ddI with VAT accumulation, which appears be involved in the increased risk of hypertension, hypercholesterolemia, and low high-density lipoprotein found in PLWH with prior exposure to thymidine analogs and/or ddI, even years after treatment discontinuation.

Oxytocin response to controlled dietary sodium and angiotensin II among healthy individuals

Oxytocin, while classically known for its role in parturition, lactation, and social behavior, also has been implicated in the control of sodium homeostasis in animal models. To improve our understanding of oxytocin physiology in humans, we measured basal oxytocin levels under low- and liberal-dietary-sodium conditions and following a peripheral angiotensin II (ANG II) infusion. Ten healthy individuals underwent a 6-day standardized low-sodium diet and a 6-day liberal-sodium diet. Each diet was followed by a graded ANG II infusion for 30-min sequential intervals at doses of 0.3, 1.0, and 3.0 ng·kg^-1·min^-1. Fasting serum oxytocin was assessed before and after ANG II infusion. Basal oxytocin levels (1,498.5 ± 94.7 vs. 1,663.3 ± 213.9 pg/ml, P = 0.51) did not differ after the low- and liberal-sodium diets. Following the ANG II infusion, ANG II levels and mean arterial pressure significantly increased as expected. In contrast, the ANG II infusion significantly lowered oxytocin levels from 1,498.5 ± 94.7 vs. 1,151.7 ± 118.1 pg/ml ( P < 0.001) on the low-sodium diet and from 1,663.3 ± 213.9 vs. 1,095.2 ± 87.4 pg/ml ( P = 0.03) on the liberal-sodium diet. The percent change in oxytocin following the ANG II infusion did not differ by sodium diet (-25 ± 5% vs. -28 ± 7% low- vs. liberal-sodium conditions, P > 0.99). Dietary sodium intake did not affect circulating oxytocin levels among healthy individuals. Systemic oxytocin levels were significantly suppressed following a peripheral ANG II infusion independent of dietary sodium conditions.

Significant Association of Aldosterone and Liver Fat Among HIV-Infected Individuals With Metabolic Dysregulation

Objective

Fatty liver disease is increased among individuals with HIV. We sought to explore how aldosterone, a key hormone linked to insulin resistance and inflammation, relates to liver fat in the large population of individuals with HIV and metabolic abnormalities.

Methods

Forty-six individuals with HIV and increased waist circumference and dysglycemia were assessed for liver fat using proton magnetic resonance spectroscopy. Serum aldosterone level was obtained following strictly controlled posture conditions and a standardized sodium diet and was related to liver fat.

Results

Among the entire group [median (interquartile range) liver fat: 5% (3%, 12%) and homeostatic model assessment of insulin resistance: 1.74 (1.21, 2.83)], serum aldosterone significantly correlated with liver fat (r = 0.31; P = 0.049). Liver fat level was significantly higher in those with aldosterone above vs below the median [8% (3%, 20%) vs 4% (2%, 10%); P = 0.02]. In the presence of metabolic syndrome, individuals with aldosterone levels above vs below the median had markedly elevated liver fat values [14% (9%, 23%) vs 5% (3%, 12%); P = 0.005] and increased presence of fatty liver disease (FLD; 92% vs 50%; P = 0.02). Controlling for metabolic syndrome, hepatitis C virus, and alcohol use, aldosterone was a significant and independent predictor of liver fat (β estimate: 0.6038, P = 0.01; overall model r² = 0.41, P = 0.0005) and FLD (OR: 1.38, P = 0.02; overall model r² = 0.28, P = 0.002).

Conclusion

These data highlight a robust association between aldosterone and liver fat among individuals with HIV and metabolic dysregulation. Increased aldosterone may be a risk factor for liver fat accumulation among the population with HIV.

Randomized, Placebo-Controlled Trial to Evaluate Effects of Eplerenone on Metabolic and Inflammatory Indices in HIV

CONTEXT

HIV-infected individuals demonstrate increased renin-angiotensin-aldosterone system activation in association with visceral adiposity, insulin resistance, and inflammation. A physiologically based treatment approach targeting mineralocorticoid receptor (MR) blockade may improve metabolic and inflammatory indices in HIV.

OBJECTIVE

To investigate effects of eplerenone on insulin sensitivity, inflammatory indices, and other metabolic parameters in HIV.

DESIGN

Six-month, double-blind, randomized, placebo-controlled trial.

SETTING

Academic clinical research center.

PARTICIPANTS

HIV-infected individuals with increased waist circumference and abnormal glucose homeostasis.

INTERVENTION

Eplerenone 50 mg or placebo daily.

OUTCOME

The primary end point was change in insulin sensitivity measured by the euglycemic-hyperinsulinemic clamp technique. Secondary end points included change in body composition and inflammatory markers.

RESULTS

Forty-six individuals were randomized to eplerenone (n = 25) vs placebo (n = 21). Eplerenone did not improve insulin sensitivity [0.48 (-1.28 to 1.48) vs 0.43 (-1.95 to 2.55) mg/min/μIU/mL insulin; P = 0.71, eplerenone vs placebo] when measured by the gold standard euglycemic-hyperinsulinemic clamp technique. Intramyocellular lipids (P = 0.04), monocyte chemoattractant protein-1 (P = 0.04), and high-density lipoprotein (P = 0.04) improved among those randomized to eplerenone vs placebo. Trends toward decreases in interleukin-6 (P = 0.10) and high-sensitivity C-reactive protein (P = 0.10) were also seen with eplerenone vs placebo. Plasma renin activity and aldosterone levels increased in the eplerenone vs placebo-treated group, demonstrating expected physiology. MR antagonism with eplerenone was well tolerated among the HIV population, with no considerable changes in blood pressure or potassium.

CONCLUSION

MR blockade may improve selected metabolic and inflammatory indices in HIV-infected individuals. Further studies are necessary to understand the clinical potential of MR antagonism in HIV.

Hypertension in people living with HIV

PURPOSE OF REVIEW

This review describes what is known concerning the burden of hypertension among people living with HIV (PLHIV), and also addresses relevant topics with respect to its risk factors and clinical management.

RECENT FINDINGS

Hypertension is highly prevalent in HIV-positive populations, and may be more common than in HIV-negative populations. Risk factors contributing to the development of hypertension in PLHIV include demographic factors, genetic predisposition, lifestyle, comorbidities such as obesity, antiretroviral therapy-related changes in body composition, and potentially also immunodeficiency, immune activation and inflammation, as well as effects from antiretroviral therapy itself. Clinical management of hypertension in PLHIV requires awareness for drug-drug interactions between antiretroviral drugs and antihypertensive drugs. Awareness, treatment, and control of hypertension in PLHIV is currently suboptimal and should be improved.

SUMMARY

The burden of hypertension among PLHIV is high and its pathophysiology most likely multifactorial. Elucidating the exact pathophysiology of hypertension in PLHIV is vital as this may provide new targets to impact and improve clinical management. In the meantime, efforts should be made to improve hypertension management as per existing clinical guidelines in order to safeguard cardiovascular health and quality of life in PLHIV.

Heart fat in HIV: marker or mediator of risk?

PURPOSE OF REVIEW

The review aims to summarize the literature describing the clinical impact of cardiac fat depots in patients with HIV infection.

RECENT FINDINGS

People living with HIV (PLHIV) have accelerated rates of cardiovascular disease, and are prone to the development of ectopic fat deposition. Specifically, PLHIV have higher volumes of epicardial and intracardiac fat quantified by noninvasive imaging. Higher volumes of epicardial fat may be related to antiretroviral therapy duration and chronic inflammation, independently of other measures of body adiposity such as BMI. They have been associated with increased coronary artery calcium, myocardial perfusion defects, death, and myocardial infarction. The association with risk may be partly mediated through direct actions of cytokines and adipokines produced by the adipose tissue. Furthermore, HIV-infected patients have increased myocardial fat deposition that is also associated with antiretroviral therapy duration, and may be responsible for myocardial systolic and diastolic dysfunction.

SUMMARY

PLHIV have increased fat deposition surrounding and inside the heart that may serve as an important imaging marker of risk but may also directly mediate coronary artery disease and cardiac dysfunction. Although robust data of targeted therapies is lacking, some pharmacotherapies may be able to reduce cardiac fat volumes. In the meantime, as the evidence grows, physicians may consider intensifying preventive strategies and monitoring in patients with abnormal heart fat on noninvasive imaging.

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

OBJECTIVE

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

DESIGN

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

METHODS

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

RESULTS

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

CONCLUSION

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

Excessive Adiposity and Metabolic Dysfunction Relate to Reduced Natriuretic Peptide During RAAS Activation in HIV

PURPOSE

Natriuretic peptides (NPs) negatively feedback on the renin-angiotensin-aldosterone system (RAAS) and play a critical role in preserving cardiac structure and maintaining metabolic homeostasis. Well-treated HIV-infected individuals are at risk for fat redistribution and demonstrate evidence of RAAS dysregulation, which relates to metabolic dysfunction. We investigated circulating NPs in relation to RAAS physiology and metrics of body composition in HIV.

METHODS

We assessed atrial natriuretic peptide, brain natriuretic peptide (BNP), and amino terminal pro B-type natriuretic peptide (NT-proBNP) during acute activation of the RAAS using a low-sodium controlled diet among 20 HIV-infected and 10 non-HIV-infected individuals well phenotyped for body composition.

RESULTS

BNP was significantly lower [median, 60 (interquartile range, 44, 152) pg/mL vs 196 (91, 251) pg/mL, respectively; P = 0.04], and serum aldosterone was higher, among HIV-infected than among non-HIV-infected individuals. BNP was significantly and inversely associated with body composition [waist circumference: r = -0.46 (P = 0.04); BMI: r = -0.55 (P = 0.01); body adiposity index: r = -0.49 (P = 0.03)], metabolic indices [total cholesterol: r = -0.44 (P = 0.05), insulin resistance calculated by using homeostatic model assessment: r = -0.44 (P = 0.05); mean arterial pressure: r = -0.44 (P = 0.05)], and serum aldosterone (r = -0.49; P = 0.03) among the HIV-infected group. These relationships were not demonstrated in the non-HIV-infected group. In a four-group comparison stratifying by HIV serostatus and above or below a body mass index (BMI) of 25 kg/m2, BNP decreased significantly across groups; it was highest in non-HIV-infected patients with a BMI <25 kg/m2 and lowest in HIV-infected patients with a BMI ≥25 kg/m2 (overall P = 0.01).

CONCLUSION

Relatively reduced NP, particularly BNP, among HIV-infected individuals with excess adiposity may contribute to reduced suppression of aldosterone and potentially drive aldosterone-mediated metabolic complications. Strategies that target RAAS blockade and/or augment NPs may be useful to reduce cardiometabolic disease among HIV-infected individuals in whom these systems are perturbed.

The Fat of the Matter: Obesity and Visceral Adiposity in Treated HIV Infection

PURPOSE OF REVIEW

The aim of this review is to summarize knowledge of the prevalence, relevant physiology, and consequences of obesity and visceral adiposity in HIV-infected adults, including highlighting gaps in current knowledge and future research directions.

RECENT FINDINGS

Similar to the general population, obesity prevalence is increasing among HIV-infected persons, and obesity and visceral adiposity are associated with numerous metabolic and inflammatory sequelae. However, HIV- and antiretroviral therapy (ART)-specific factors may contribute to fat gain and fat quality in treated HIV infection, particularly to the development of visceral adiposity, and sex differences may exist. Obesity and visceral adiposity commonly occur in HIV-infected persons and have significant implications for morbidity and mortality. Future research should aim to better elucidate the HIV- and ART-specific contributors to obesity and visceral adiposity in treated HIV infection, with the goal of developing targeted therapies for the prevention and treatment of obesity and visceral adiposity in the modern ART era.

Practical Review of Recognition and Management of Obesity and Lipohypertrophy in Human Immunodeficiency Virus Infection

Background

Obesity and lipohypertrophy are common in treated human immunodeficiency virus (HIV) infection and contribute to morbidity and mortality among HIV-infected adults on antiretroviral therapy (ART).

Methods

We present a consensus opinion on the diagnosis, clinical consequences, and treatment of excess adiposity in adults with treated HIV infection.

Results

Obesity and lipohypertrophy commonly occur among HIV-infected adults on ART and may have overlapping pathophysiologies and/or synergistic metabolic consequences. Traditional, HIV-specific, and ART-specific risk factors all contribute. The metabolic and inflammatory consequences of excess adiposity are critical drivers of non-AIDS events in this population. Although promising treatment strategies exist, further research is needed to better understand the pathophysiology and optimal treatment of obesity and lipohypertrophy in the modern ART era.

Conclusions

Both generalized obesity and lipohypertrophy are prevalent among HIV-infected persons on ART. Aggressive diagnosis and management are key to the prevention and treatment of end-organ disease in this population and critical to the present and future health of HIV-infected persons.

Insulin Resistance in HIV-Patients: Causes and Consequences

Here we review how immune activation and insulin resistance contribute to the metabolic alterations observed in HIV-infected patients, and how these alterations increase the risk of developing CVD. The introduction and evolution of antiretroviral drugs over the past 25 years has completely changed the clinical prognosis of HIV-infected patients. The deaths of these individuals are now related to atherosclerotic CVDs, rather than from the viral infection itself. However, HIV infection, cART, and intestinal microbiota are associated with immune activation and insulin resistance, which can lead to the development of a variety of diseases and disorders, especially with regards to CVDs. The increase in LPS and proinflammatory cytokines circulating levels and intracellular mechanisms activate serine kinases, resulting in insulin receptor substrate-1 (IRS-1) serine phosphorylation and consequently a down regulation in insulin signaling. While lifestyle modifications and pharmaceutical interventions can be employed to treat these altered metabolic functions, the mechanisms involved in the development of these chronic complications remain largely unresolved. The elucidation and understanding of these mechanisms will give rise to new classes of drugs that will further improve the quality of life of HIV-infected patients, over the age of 50.