Fenofibrate improves the atherogenic lipid profile and enhances LDL resistance to oxidation in HIV-positive adults

Fenofibrate for COVID-19 and related complications as an approach to improve treatment outcomes: the missed key for Holy Grail

Introduction

Fenofibrate is an agonist of peroxisome proliferator activated receptor alpha (PPAR-α), that possesses anti-inflammatory, antioxidant, and anti-thrombotic properties. Fenofibrate is effective against a variety of viral infections and different inflammatory disorders. Therefore, the aim of critical review was to overview the potential role of fenofibrate in the pathogenesis of SARS-CoV-2 and related complications.

Results

By destabilizing SARS-CoV-2 spike protein and preventing it from binding angiotensin-converting enzyme 2 (ACE2), a receptor for SARS-CoV-2 entry, fenofibrate can reduce SARS-CoV-2 entry in human cells Fenofibrate also suppresses inflammatory signaling pathways, which decreases SARS-CoV-2 infection-related inflammatory alterations. In conclusion, fenofibrate anti-inflammatory, antioxidant, and antithrombotic capabilities may help to minimize the inflammatory and thrombotic consequences associated with SARSCoV-2 infection. Through attenuating the interaction between SARS-CoV-2 and ACE2, fenofibrate can directly reduce the risk of SARS-CoV-2 infection.

Conclusions

As a result, fenofibrate could be a potential treatment approach for COVID-19 control.

Obstructive Sleep Apnea Affects Lacrimal Gland Function

Purpose

To determine the effect of obstructive sleep apnea syndrome (OSA) on lacrimal gland function and its mechanism.

Methods

Male mice aged seven to eight weeks were housed in cages with cyclic intermittent hypoxia to mimic OSA, and the control group was kept in a normal environment. Slit-lamp observation, fluorescein staining, and corneal sensitivity detection are used to assess cornea changes. Tear secretion was detected by phenol red cotton thread, and the pathological changes of lacrimal gland were observed by hematoxylin and eosin staining, oil red O staining, cholesterol and triglyceride kits, immunofluorescence staining, immunohistochemical staining, real-time polymerase chain reaction, transmission electron microscopy, and Western blot.

Results

Studies revealed a decreased tear secretion, corneal epithelial defects and corneal hypersensitivity. Myoepithelial cell damage, abnormal lipid accumulation, reduced cell proliferation, increased apoptosis and inflammatory cell infiltration in the lacrimal gland were also seen. Hifα and NF-κB signaling pathways, moreover, were activated, while Pparα was downregulated, in the lacrimal glands of OSA mice. Fenofibrate treatment significantly alleviated pathological changes of the lacrimal gland induced by OSA.

Conclusion

OSA disturbs the Hifα/Pparα/NF-κB signaling axis, which affects lacrimal gland structure and function and induces dry eye.

Exploration and Development of PPAR Modulators in Health and Disease: An Update of Clinical Evidence

Peroxisome proliferator-activated receptors (PPARs) are nuclear receptors that govern the expression of genes responsible for energy metabolism, cellular development, and differentiation. Their crucial biological roles dictate the significance of PPAR-targeting synthetic ligands in medical research and drug discovery. Clinical implications of PPAR agonists span across a wide range of health conditions, including metabolic diseases, chronic inflammatory diseases, infections, autoimmune diseases, neurological and psychiatric disorders, and malignancies. In this review we aim to consolidate existing clinical evidence of PPAR modulators, highlighting their clinical prospects and challenges. Findings from clinical trials revealed that different agonists of the same PPAR subtype could present different safety profiles and clinical outcomes in a disease-dependent manner. Pemafibrate, due to its high selectivity, is likely to replace other PPARα agonists for dyslipidemia and cardiovascular diseases. PPARγ agonist pioglitazone showed tremendous promises in many non-metabolic disorders like chronic kidney disease, depression, inflammation, and autoimmune diseases. The clinical niche of PPARβ/δ agonists is less well-explored. Interestingly, dual- or pan-PPAR agonists, namely chiglitazar, saroglitazar, elafibranor, and lanifibranor, are gaining momentum with their optimistic outcomes in many diseases including type 2 diabetes, dyslipidemia, non-alcoholic fatty liver disease, and primary biliary cholangitis. Notably, the preclinical and clinical development for PPAR antagonists remains unacceptably deficient. We anticipate the future design of better PPAR modulators with minimal off-target effects, high selectivity, superior bioavailability, and pharmacokinetics. This will open new possibilities for PPAR ligands in medicine.

Drug therapies for HIV-related metabolic disorders

INTRODUCTION

Human immunodeficiency virus (HIV) has become a chronic disease often associated with dyslipidaemia and insulin resistance. Combination antiretroviral therapy (cART) may contribute to metabolic disturbances, eventually leading to increased cardiovascular disease (CVR) in this population. Escalating interventions to decrease CVR include promoting a healthy lifestyle, such as quitting smoking, diet and regular exercise. If they do not achieve the goals, a change of cART should be considered, followed by or used concomitantly with the use of chemical therapies.

AREAS COVERED

The aim of this article is to review the available drug therapies for the treatment of metabolic disorders in HIV-infected patients and to examine their safety and effectiveness in this population. A review of the literature was conducted, highlighting the most relevant articles.

EXPERT OPINION

Switching strategies can be useful but its expected benefit is not high. Therefore, chemical intervention is often needed. Statins have been proven to reduce CVR in the general population and in HIV-infected patients. Simvastatin is contraindicated in patients treated with boosted PI due to interactions; atorvastatin is safe at submaximal dose and needs close monitoring, while pravastatin lacks lipid-lowering potency, and rosuvastatin and pitavastatin are safe. Ezetimibe and fibrates are also safe and effective in HIV-infected patients and can be used in combination with statins. The management of glucose homeostatic disorders in HIV-infected patients follows the same guidelines as in the general population. However, there are specific considerations with respect to the interactions of particular medications with cART. When drug therapy is needed, metformin is the first-line drug. Decisions regarding second- and third-line drugs should be carefully individualized.

Clinical management of dyslipidaemia associated with combination antiretroviral therapy in HIV-infected patients

The introduction of potent combination antiretroviral therapy (cART) has had a remarkable impact on the natural history of HIV infection, leading to a dramatic decline in the mortality rate and a considerable increase in the life expectancy of HIV-positive people. However, cART use is frequently associated with several metabolic complications, mostly represented by lipid metabolism alterations, which are reported very frequently among persons treated with antiretroviral agents. In particular, hyperlipidaemia occurs in up to 70%-80% of HIV-positive subjects receiving cART and is mainly associated with specific antiretroviral drugs belonging to three classes of antiretroviral agents: NRTIs, NNRTIs and PIs. The potential long-term consequences of cART-associated dyslipidaemia are not completely understood, but an increased risk of premature coronary heart disease has been reported in HIV-infected patients on cART, so prompt correction of lipid metabolism abnormalities is mandatory in this population. Dietary changes, regular aerobic exercise and switching to a different antiretroviral regimen associated with a more favourable metabolic profile are the first steps in clinical management, but lipid-lowering therapy with fibrates or statins is often required. In this case, the choice of hypolipidaemic drugs should take into account the potential pharmacokinetic interactions with many antiretroviral agents.

A Prospective, Multicentre, Open-Label Single-Arm Exploratory Study to Evaluate Efficacy and Safety of Saroglitazar on Hypertriglyceridemia in HIV Associated Lipodystrophy

Objective

This study was designed to explore the efficacy and safety of saroglitazar 4 mg on hypertriglyceridemia in patients with HIV associated lipodystrophy.

Methods

During this 12-week prospective, multi-centric, open-label, single arm exploratory study, 50 patients were enrolled to receive saroglitazar 4 mg orally once daily in the morning before breakfast. The primary efficacy endpoint was the percent change in triglyceride (TG) levels from baseline to Week 6 and Week 12. The secondary efficacy endpoints were assessment of low-density-lipoprotein (LDL), very-low-density-lipoprotein (VLDL), high-density-lipoprotein (HDL), non-HDL cholesterol, total cholesterol, apo-lipoprotein (Apo) A1, Apo B, and C-peptide and fasting insulin for HOMA beta and HOMA IR. Safety assessment was performed during the study.

Results

Saroglitazar 4 mg significantly decreased the serum TG levels from baseline at Week 6 (percent change: -40.98; 95% CI: -50.82, -31.15) and Week 12 (percent change -45.11; 95% CI: -52.37, -37.86). Reduction in VLDL cholesterol (percent change: -46.33; 95% CI: -52.89, -39.76) and total cholesterol (percent change: 7.37; 95% CI: 1.96, 12.78) was observed at week 12 from baseline. Saroglitazar increased HDL cholesterol (percent change: 34.56, 95% CI: 22.22, 46.90), Apo A1 (percent change: 33.16; 95% CI: 18.69, 47.63) and Apo B (percent change: 10.55, 95% CI: 2.86, 18.25) levels at week 12 from baseline. Saroglitazar treatment led to increase in the C-peptide (percent change: 59.42, 95% CI: 48.78, 70.06), fasting insulin levels (percent change: 47.10; 95% CI: 38.63, 55.57), HOMA of beta cell function for C-peptide (percent change: 71.67; 95% CI: 39.09, 104.26) and HOMA of insulin resistance for C-peptide (percent change: 58.29, 95% CI: 46.74, 69.83) at week 12 from baseline. Saroglitazar treatment was safe and well tolerated in this study.

Conclusion

Overall, the observed changes in lipid profile after 12 weeks of saroglitazar treatment were in the direction of improvement in patients with HIV associated lipodystrophy.

Trial Registration

Clinical Trial Registry of India Phase II/CTRI/2010/091/000107

Treatment of dyslipidemia in HIV

Patients infected with HIV have a high risk of developing dyslipidemia. Effective therapeutic strategies can be challenging due to an increase risk of drug interactions and other comorbidities. Understanding the underlying pathophysiology and the principles of pharmacological and non-pharmacological therapeutic interventions can be of value in the appropriate management of dyslipidemia in the HIV-infected patient.

Managing dyslipidemia in HIV/AIDS patients: challenges and solutions

Human immunodeficiency virus (HIV) is a chronic disease associated with dyslipidemia and insulin resistance. In addition, the administration of combination antiretroviral therapy is associated with an increase in the incidence of metabolic risk factors (insulin resistance, lipoatrophy, dyslipidemia, and abnormalities of fat distribution in HIV patients). HIV dyslipidemia is a common problem, and associated with an increase in incidence of cardiovascular disease. Further challenges in the management of HIV dyslipidemia are the presence of diabetes and metabolic syndrome, nonalcoholic fatty liver disease, hypothyroidism, chronic kidney disease, the risk of diabetes associated with statin administration, age and ethnicity, and early menopause in females. Dyslipidemia in patients with HIV is different from the normal population, due to the fact that HIV increases insulin resistance and HIV treatment not only may induce dyslipidemia but also may interact with lipid-lowering medication. The use of all statins (apart from simvastatin and lovastatin) is safe and effective in HIV dyslipidemia, and the addition of ezetimibe, fenofibrate, fish oil, and niacin can be used in statin-unresponsive HIV dyslipidemia. The management of dyslipidemia and cardiovascular disease risks associated with HIV is complex, and a certain number of patients may require management in specialist clinics run by specialist physicians in lipid disorders. Future research is needed to address best strategies in the management of hyperlipidemia with HIV infection.

Dyslipidemia in HIV-infected individuals

Metabolic complications continue to play a major role in the management of HIV infection. Dyslipidemia associated with HIV infection and with the use of combined antiretroviral therapy includes elevations in triglycerides, reduced high-density cholesterol, and variable increases in low-density and total cholesterol. The association between dyslipidemia and specific antiretroviral agents has been underscored. Multiple pathogenic mechanisms by which HIV and antiretroviral agents lead to dyslipidemia have been hypothesized, but they are still controversial. The potential clinical and pathological consequences of HIV-associated hyperlipidemia are not completely known, but several studies reported an increased risk of coronary artery disease in HIV-positive individuals receiving combined antiretroviral therapy. HIV-infected persons who have hyperlipidemia should be managed similarly to those without HIV infection in accordance with the National Cholesterol Education Program. Life style changes are the primary target. Statins and fibrates and/or modification in antiretroviral therapy are possible approaches to this problem.

Management of dyslipidemia in HIV-infected patients

Antiretroviral therapy has dramatically increased survival for HIV-infected individuals. As this population lives longer, coronary heart disease has become an important comorbid condition. Dyslipidemia in HIV-infected individuals is a complex condition, with multiple contributing factors including the HIV virus itself, individual genetic characteristics and antiretroviral therapy-induced metabolic changes. Effective management of dyslipidemia in this population is essential to reduce cardiovascular risk but presents multiple challenges due to interactions between antiretroviral therapy agents and lipid-lowering medications.

Combination of niacin and fenofibrate with lifestyle changes improves dyslipidemia and hypoadiponectinemia in HIV patients on antiretroviral therapy: results of "heart positive," a randomized, controlled trial

CONTEXT

HIV patients on antiretroviral therapy (ART) have a unique dyslipidemia [elevated triglycerides and non-high-density lipoprotein-cholesterol (HDL-C), low HDL-C] with insulin resistance (characterized by hypoadiponectinemia).

OBJECTIVE

The aim was to test a targeted, comprehensive, additive approach to treating the dyslipidemia.

DESIGN AND SETTING

We conducted a randomized, double-blind, placebo-controlled, 24-wk trial of lifestyle modification, fenofibrate, and niacin in multiethnic HIV clinics at an academic center.

PARTICIPANTS

Hypertriglyceridemic adult patients were stratified on three combinations of ART classes. Subjects retained at the first measurement (2 wk) after entry were included in the analysis (n = 191).

INTERVENTIONS

Subjects were randomized into five treatment groups: usual care (group 1); low-saturated-fat diet and exercise (D/E; group 2); D/E + fenofibrate (group 3); D/E + niacin (group 4); or D/E + fenofibrate + niacin (group 5).

MAIN OUTCOME MEASURES

We measured changes in fasting triglycerides, HDL-C, and non-HDL-C (primary), and in insulin sensitivity, glycemia, adiponectin, C-reactive protein, energy expenditure, and body composition (secondary). Data were analyzed as a factorial set of treatment combinations using a mixed repeated measures model, last observation carried forward, and complete case approaches (groups 2-5), and as an unstructured set of treatments (groups 1-5).

RESULTS

Fenofibrate improved triglycerides (P = 0.002), total cholesterol (P = 0.02), and non-HDL-C (P = 0.003), whereas niacin improved HDL-C (P = 0.03), and both drugs decreased the total cholesterol-to-HDL-C ratio (P = 0.005-0.01). The combination of D/E, fenofibrate, and niacin provided maximal benefit, markedly reducing triglycerides (-52% compared to usual care; P = 0.003), increasing HDL-C (+12%; P < 0.001), and decreasing non-HDL-C (-18.5%; P = 0.003) and total cholesterol-to-HDL-C ratio (-24.5%; P < 0.001). Niacin doubled adiponectin levels.

CONCLUSIONS

A combination of fenofibrate and niacin with low-saturated-fat D/E is effective and safe in increasing HDL-C, decreasing non-HDL-C and hypertriglyceridemia, and ameliorating hypoadiponectinemia in patients with HIV/ART-associated dyslipidemia.

Treatment with pravastatin and fenofibrate improves atherogenic lipid profiles but not inflammatory markers in ACTG 5087

OBJECTIVES

Statins and fibrates alter lipids, apolipoproteins and inflammatory markers in persons without HIV. The objective of this study was to evaluate changes in lipoproteins, apolipoproteins and other markers of inflammation with the use of pravastatin and fenofibrate.

DESIGN

Evaluation of participants in ACTG A5087, a randomized trial of pravastatin 40 mg/day or fenofibrate 200 mg/day for the treatment of dyslipidemia. Participants that failed single-agent therapy at week 12 were given the combination.

METHODS

Participants with available specimens were tested for apolipoproteins A1 and B, adiponectin, plasminogen-activator inhibitor type 1 (PAI-1), P-selectin, and high-sensitivity C-reactive protein (hs-CRP).

RESULTS

74 participants (37 per randomized arm) received either pravastatin or fenofibrate for 12 weeks with 60 receiving combination treatment from weeks 12-48. There were no significant changes in hs-CRP, PAI-1, and P-selectin. From baseline to week 12, the median Apo B levels (-8 mg/dL, P=0.01 for fenofibrate and -27 mg/dL, P<0.01 for pravastatin) and ApoB/A1 ratios (-0.16, P<0.01 for both arms) significantly decreased. From baseline to week 48, median adiponectin (-1 ng/dL, P<0.01), Apo B (-22 mg/dL, P<0.01) and Apo B/A1 ratios (-0.2, P<0.01) all decreased in those who went on combination therapy, whereas Apo A1 (9.5 mg/dL, P=0.01) levels increased.

CONCLUSION

Treatment with pravastatin or fenofibrate improves the atherogenic lipid profile within the first 12 weeks and is sustained through 48 weeks with combination therapy. Adiponectin levels decrease with lipid-lowering therapy. However, markers of inflammation and platelet activation were not appreciably changed suggesting that the biologic properties of these agents differ in persons with HIV infection.

HIV and HAART-Associated Dyslipidemia

Effective highly active antiretroviral therapy (HAART) for human immunodeficiency virus-1 (HIV) infection has led to marked improvement in life-expectancy for those infected with HIV. Despite reductions in the incidence of AIDS with effective treatment, patients continue to experience considerable morbidity and mortality from non-AIDS illness such as premature cardiovascular disease, liver failure and renal failure. These morbidities, particularly premature cardiovascular disease, are thought to be related to a combination of the effects of an ageing HIV-infected population coupled with long-term effects of HIV infection and antiretroviral therapy (ART). One of the principle drivers behind the well documented increase in the risk of cardiovascular disease in HIV-infected patients is dyslipidemia.

This review will focus on the clinical presentation of HIV and ART-associated dyslipidemia, what is known of its patho-physiology, including associations with use of specific antiretroviral medications, and suggest screening and management strategies.

Fenofibrate in the treatment of dyslipidemia associated with HIV infection

IMPORTANCE TO THE FIELD

Dyslipidemia is common among HIV-infected patients receiving antiretroviral therapy. A higher risk of coronary heart disease (CHD) is associated with specific antiretroviral medications. The aging of HIV infected people and the intersection of other CHD risk factors have led to the need for developing effective interventions to lower the risk of CHD events.

AREAS COVERED IN THIS REVIEW

The authors review current literature on the use of fenofibrate and related derivatives in HIV-infected people with dyslipidemia using antiretroviral therapy.

WHAT THE READER WILL GAIN

Fibrates have been demonstrated to reduce the risk of CHD events in HIV seronegative individuals with mixed results on survival benefits. There are no published studies of CHD outcomes using fibrates in people with HIV infection. Several studies conducted in HIV infected people demonstrate the ability of fenofibrate to lower triglycerides and increase high-density lipoprotein cholesterol levels with few adverse events. The authors review the pharmacology and clinical efficacy/safety of the use of fenofibrate in people with HIV infection.

TAKE HOME MESSAGE

Fenofibrate is a generally safe and useful agent for the treatment of mixed dyslipidemia and hypertriglyceridemia in people with HIV infection though limited data are available particularly on clinical outcomes.

Premature onset of cardiovascular disease in HIV-infected individuals: the drugs and the virus

Life expectancy in HIV-infected individuals has been greatly enhanced through immunologic restoration and virologic suppression resulting from antiretroviral therapy. Current clinical HIV care in Western countries focuses on treatment of drug toxicities and prevention of comorbidities. These non-AIDS HIV-related comorbidities, such as cardiovascular disease, occur even in individuals with virologic suppression and manifest at an earlier age than when normally presenting in the general population. While traditional risk factors are present in many HIV-infected individuals who develop cardiovascular disease, the additional roles of HIV-related chronic inflammation and immune activation as well as chronic HIV viremia may be significant. This review provides current evidence for the contributions of the virus, in terms of both chronic viremia and its contribution via chronic low-level inflammation, immune activation, premature immune senescence and dyslipidemia, to the pathogenesis of HIV-related cardiovascular disease, and balances this against the propensity of specific antiretroviral therapies to cause cardiovascular disease, in particular through altered cholesterol metabolism.

Treatment of dyslipidemia in HIV-infected patients

IMPORTANCE OF THE FIELD

Patients infected with HIV are at high risk for dyslipidemia, insulin resistance and cardiovascular disease. Therapies to reverse these risks are complex, sometimes controversial, and not uniformly effective.

AREAS COVERED IN THIS REVIEW

Pathophysiology of the lipid abnormalities in HIV is discussed, including the causes of alterations in triglycerides, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol and insulin resistance. We discuss the therapy of dyslipidemia in HIV using a combination of available clinical evidence and expert opinion based on extensive clinical experience, with discussions of lifestyle intervention and diet, conventional pharmacotherapy with lipid-lowering medications including statins, fibrates, niacin and thiazolidinediones for dyslipidemia, and newer therapeutic approaches including omega fatty acids, acipimox, growth hormone and leptin.

WHAT THE READER WILL GAIN

A detailed understanding of the pathophysiology and rational or evidence-based approach to therapy of lipid abnormalities in patients infected with HIV.

TAKE HOME MESSAGE

Treatment of dyslipidemia in patients with HIV is challenging and complicated by the risk of drug interactions. Appropriate therapy requires a sound understanding of pathophysiology and the principles of pharmacological and nonpharmacological therapeutic interventions. An evidence-based approach that combines lifestyle changes and drugs that are both safe and effective, singly and in combination, is described.

Lipid management in patients who have HIV and are receiving HIV therapy

Dyslipidemia now is recognized as a significant potential adverse event in HIV-infected patients who are receiving antiretroviral therapy. HIV-infected persons who have hyperlipidemia should be managed similarly to those without HIV infection in accordance with the National Cholesterol Education Program. Providers must treat the HIV infection first; if dyslipidemia develops, patients should be prescribed lipid-lowering therapies or should consider modifying their current antiretroviral therapy, if indicated. Evidence for these two strategies is discussed.

Treatment of hyperlipidaemia with fenofibrate and related fibrates

BACKGROUND

Fenofibrate is the most widely used fibrate. Its efficacy and tolerability in the treatment of hypertriglyceridaemia and combined hyperlipidaemia have been demonstrated in several clinical trials.

OBJECTIVE

To review the pharmacology, lipid-lowering and extra-lipid effects of fenofibrate and to preview ABT-335, an investigational new fenofibric acid molecule.

RESULTS

The effects of fenofibrate are mediated through the active metabolite fenofibric acid, and are described in detail in the paper. ABT-335 is a salt of fenofibric acid and, unlike fenofibrate, does not require first pass metabolism to the active moiety. ABT-335 is being developed for combination use with statins, and has recently completed three large Phase III randomised controlled trials in which the efficacy and safety of ABT-335 in combination with the three most commonly prescribed statins, atorvastatin, simvastatin and rosuvastatin, was evaluated in patients with mixed dyslipidaemia.

CONCLUSION

ABT-335 in combination with statins may provide a safe and efficacious treatment modality that enables achievement of several therapeutic goals in patients with mixed dyslipidaemia who have high cardiovascular risk.

Lipid and apoprotein profile in HIV-1-infected patients after CD4-guided treatment interruption

OBJECTIVES

The aims of the present study were to determine if metabolic abnormalities and cytokine derangements are modified in HIV-1-infected patients after 12 months on treatment interruption (TI).

DESIGN

The design of this study was prospective randomized study.

METHODS

Longitudinal multicenter study in HIV-1-infected patients with a 12-month follow-up. Patients on stable highly active antiretroviral therapy, with CD4 count >600/microL and HIV RNA <50 copies/mL for at least 6 months, were randomized to interrupt therapy or continue ongoing highly active antiretroviral therapy. Lipids (total cholesterol, triglycerides), apoproteins (A1, B, and E), and adipocytokines (leptin, adiponectin, plasminogen activator inhibitor-1, monocyte chemotactic protein-1, Interleukin-6, Interleukin-8, and tumor necrosis factor-alpha) were measured at baseline and at month 12. Multiplex suspension bead array immunoassay was performed using the Luminex 100 analyzer to identify protein expression in plasma.

RESULTS

Patients who underwent TI (n = 19) had a significant decrease in median cholesterol levels (P < 0.001), while median triglyceride levels remained unchanged. There was a significant decrease in Apo-A1 levels (P = 0.048) and Apo-B levels (P < 0.001) and an increase in tumor necrosis factor-alpha levels (P = 0.034). Given the greater decrease in Apo-B, the ratio Apo-A1/Apo-B increased after 12 months of TI (from 3.4 to 5.1, P = 0.008). We did not find significant variations in leptin or adiponectin levels. In patients who continued on highly active antiretroviral therapy (n = 18), there were no significant changes in any of the measured parameters.

CONCLUSION

The lipid profile and apoproteins levels change toward a less atherogenic profile after TI, arguing against a lipid-mediated mechanism to explain the increased cardiovascular risk in patients who interrupt treatment.

Association of non-HDL cholesterol with subclinical atherosclerosis in HIV-positive patients

OBJECTIVES

To assess the relationship between non-classical cardiovascular (CV) risk factors including non-HDL cholesterol (non-HDL-C), apolipoprotein B, triglycerides to HDL ratio, LDL size, inflammation or oxidative stress parameters and carotid intima-media thickness (CIMT), in order to better identify prevention or therapeutic targets. In addition, we studied the relationship between metabolic syndrome (MS) and CIMT.

METHODS

Cross-sectional study including 232 HIV-positive (HIV+) adults (80% treated by combined antiretroviral therapy) extracted from the ANRS CO3 Aquitaine Cohort.

RESULTS

There was a significant association of higher non-HDL-C (p<0.01), apolipoprotein B (p<0.01) levels or TG/HDL ratio (p<0.05) with higher CIMT when compared the first vs fourth quartile, while there is no association between CIMT and LDL-C (p=0.09) or LDL size (p=0.55). In multivariate analysis, only the TG/HDL molar ratio > 1.5 tend toward significance (p=0.08). MS was observed in only 7.3% of patients with the NCEP-ATP III definition and 11.2% with the IDF criteria. Whatever the used definition, there was a significant association between MS presence and increased CIMT (p<0.05) in univariate and multivariate model.

CONCLUSIONS

Non-HDL-C, TG/HDL ratio and apolipoprotein B levels, which are closely linked to lipid disorders associated to the MS, appear as stronger predictive markers than LDL-C for screening subclinical atherosclerosis in HIV+ populations. Achieving non-HDL-C target defined by the NCEP-ATP III guidelines appears of great importance to reduce CV complications in HIV+ patients.

HIV lipodystrophy and its metabolic consequences: implications for clinical practice

BACKGROUND

The introduction of highly active antiretroviral therapy (HAART) around 1996 markedly reduced mortality and morbidity from human immunodeficiency virus (HIV) infection. As life expectancy has improved, the chronic complications of HIV and HAART have become increasingly relevant.

SCOPE

This article provides an overview of the HIV-associated lipodystrophy, its pathogenesis and its clinical consequences (based on a search strategy in PubMed including literature published to November 2007).

FINDINGS

Lipodystrophy syndrome is characterized by abnormal fat distribution syndrome associated with metabolic disturbances and includes insulin resistance, deranged glucose and lipid metabolism. It is associated with increased risks of progression to type 2 diabetes and cardiovascular disease. Robust diagnostic criteria are required for lipodystrophy, and subsequent prospective cohort studies and randomized controlled trials are then required to determine the etiology and prognosis of lipodystrophy, and to evaluate therapeutic interventions for this consequence of HAART. Therapies to improve insulin resistance have been tried but they are frequently ineffective, and are limited by potential toxicity in this population. Hence, current management options for HIV associated lipodystrophy are limited and are mostly based on avoidance of risk factors and switching of antiretroviral drugs.

CONCLUSION

As the '3 by 5 strategy' of providing HIV drugs to the developing world is implemented worldwide, the numbers of patients adhering to antiretroviral medicines is dramatically increasing. One must be aware that in reducing the burden of acute retroviral disease, the treatments proposed might lead to significant rates of metabolic complications and further exacerbation of the epidemic of diabetes and cardiovascular disease.

The management of dyslipidaemias in antiretroviral-treated HIV infection: a systematic review

OBJECTIVES

The aim of the study was to assess the currently available evidence concerning the management of dyslipidaemias in HIV-infected individuals treated with antiretroviral therapy.

METHODS

Randomized trials, published within the 5 years preceding 5 October 2005, were identified in PubMed Medline, Embase, and The Cochrane Central Register of Controlled Trials. Studies were then included or excluded, dependent on their meeting inclusion/exclusion criteria. The evidence obtained in the studies that were included was assessed using methods employed by the Scottish Intercollegiate Guidelines Network (SIGN).

RESULTS

Thirteen relevant trials were identified, concerning the use of statins, fibrates, antiretroviral drug switches and insulin-sensitizing drugs. Most contained small numbers of trial participants.

CONCLUSIONS

Most studies suggested beneficial effects and satisfactory safety profiles for the interventions studied. However, the insulin-sensitizing drug rosiglitazone appeared to have some detrimental effects on lipid profiles. With the small numbers of participants in the majority of studies, these studies were likely to have been inadequately powered to assess the effects of the interventions examined. Larger trials are therefore necessary.

Use of metabolic drugs and fish oil in HIV-positive patients with metabolic complications and associations with dyslipidaemia and treatment targets

BACKGROUND

Highly active antiretroviral therapy (HAART) with protease inhibitors (PI) is successful in suppressing viral replication, but may lead to a range of metabolic abnormalities associated with cardiovascular disease (CVD).

OBJECTIVES

The first objective of the study was to compare baseline demographic and clinical characteristics between PI users and non-PI users referred to a specialized metabolic clinic during 1999-2003. The second objective was to assess the associations of prescription drugs and fish oil with dyslipidaemia and to determine whether or not patients achieved treatment targets during 6 months of treatment.

METHODS

A retrospective analysis was performed using two sets of charts based on standardized forms with entries for personal data, drug treatment and clinical history. Anonymous linkage with the British Columbia HIV/AIDS Drug Treatment Program and the hospital laboratory was performed to gather information about HAART prescriptions and blood work.

RESULTS

In total, 237 patients were included in the study. There were few differences in any demographic or clinical factors between PI users and non-PI users. Compared with controls not taking lipid-lowering drugs or fish oil (n=48), statins appeared to be the only agent that was significantly associated with a reduced total cholesterol concentration (-15.6%; P=0.009). Fibrate treatment was associated with the largest reduction of triglyceride concentration (-37.4%; P=0.012), closely followed by fish oil (n=18;-32%; P=0.027). Six-month treatment success rates ranged between 17 and 43% of patients for total cholesterol (<5.2 mmol/L) and between 15 and 44% of patients for triglycerides (<2.3 mmol/L).

CONCLUSIONS

Despite the apparent lowering of blood lipids with drug and fish oil treatments, a majority of patients in these treatment groups (56.5-83.3%) still had elevated concentrations after 6 months.

The clinical significance of the size of low-density-lipoproteins and the modulation of subclasses by fibrates

BACKGROUND

Beyond total low-density-lipoproteins (LDL) levels, increasing evidence suggests that the 'quality' of LDL exerts a great influence on the cardiovascular risk. Several studies have also shown that the therapeutic modulation of LDL size is of benefit in reducing the risk of cardiovascular events. Hypolipidaemic treatment is able to alter LDL subclass distribution but strong variations have been noticed among different agents. Fibrates have a major impact on triglyceride metabolism and in modulating LDL size and subclasses, but variations exist among the different molecules.

METHODOLOGY

A literature search (by Medline and Scopus) was performed using the following headings: 'small dense LDL', 'LDL size', 'LDL subfractions', 'LDL subclasses', 'LDL distribution' and 'fenofibrate', 'bezafibrate', 'ciprofibrate' and 'gemfibrozil' up to 20 January 2007. The authors also manually reviewed the references of selected articles for any pertinent material.

RESULTS

Analysis of all published studies revealed that treatment with fenofibrate, ciprofibrate, bezafibrate and gemfibrozil is usually beneficial, and fenofibrate may be more efficacious than the other molecules. This is supported by using all the available techniques in subjects with a very wide range of lipid alterations.

CONCLUSION

Among the different agents, fenofibrate has been found to be particularly effective in modulating LDL size and subclasses in patients at higher cardiovascular risk, such as those with type 2 diabetes or the metabolic syndrome.

Reduction in triglyceride level with N-3 polyunsaturated fatty acids in HIV-infected patients taking potent antiretroviral therapy: a randomized prospective study

To assess the evolution of triglyceride (TG) levels in HIV-infected patients receiving stable potent antiretroviral therapy treated with N-3 polyunsaturated fatty acids (PUFAs), a prospective double-blind randomized design for a reliable assessment of TG evolution was performed. One hundred twenty-two patients with TG levels >2 g/L and < or =10 g/L after a 4-week diet (baseline TG: 4.5 +/- 1.9 g/L) were randomized for 8 weeks to N-3 PUFAs (2 capsules containing 1 g of fish oil 3 times daily, n = 60), or placebo (1 g of paraffin oil capsules, n = 62). An 8-week open-label phase of N-3 PUFAs followed. Evaluation criteria were TG percent change at week 8, percentage of responders (normalization or > or =20% TG decrease), and safety issues. Ten patients with baseline TG levels >10 g/L were not randomized and received N-3 PUFAs as open treatment. The difference (PUFA - placebo) in TG percent change at week 8 was -24.6% (range: -40.9% to -8.4%; P = 0.0033), the median was -25.5% in the PUFA group versus 1% in the placebo group, and mean TG levels at week 8 were 3.4 +/- 1.8 g/L and 4.8 +/- 3.1 g/L, respectively. TG levels were normalized in 22.4% (PUFA) versus 6.5% (placebo) of patients (P = 0.013) with a > or =20% reduction in 58.6% (PUFA) versus 33.9% (placebo) of patients (P = 0.007). Under the open-label phase of N-3 PUFAs, the decrease in TG levels was sustained at week 16 for patients in the PUFA group (mean TG: 3.4 +/- 1.7 g/L), whereas a 21.2% decrease in TG levels occurred for patients in the placebo group (mean TG: 3.3 +/- 1.4 g/L). No significant differences were observed between groups in the occurrence of adverse events. The median TG change at week 8 was -43.6% (range: Q1-Q3; 95% CI: -66.5% to -4.6%) for patients with baseline TG levels >10 g/L. The difference in mean total cholesterol between groups (PUFA - placebo) at week 8 was -8.5% (P = 0.0117). This study demonstrated the efficacy of PUFAs to lower elevated TG levels in treated HIV-infected hypertriglyceridemic patients. N-3 PUFAs have a good safety profile.

Venous and arterial thrombosis in patients with HIV infection

Thromboembolic complications in HIV-infected patients have been reported. To our knowledge, no case-control studies have compared the prevalence of thromboembolic events between HIV-positive and HIV-negative individuals. One hundred and sixty-nine HIV-infected patients and 180 randomly selected blood donors were enrolled. Selected patients completed a specific questionnaire and were subsequently interviewed. Information was collected on family and personal history of cardiovascular disorders and the presence of personal risk factors for venous and arterial thrombosis. All reported events were adjudicated only if adequate documentation of objective tests was available. Mean age and sex were similar in the two groups. A vascular event was documented in six HIV-infected patients (3.55%) and in none of the controls (P=0.0108). Family history of cardiovascular disorders, cigarette smoking and hypertriglyceridemia were more prevalent in HIV patients than in controls. In multivariate analysis, neither family traditional cardiovascular risk factors nor HIV infection were independently associated with the presence of thromboembolic events. The results confirm the hypothesis that HIV-positive patients have an increased risk of thromboembolic disorders. Whether this increased risk has been provoked by HIV infection itself or by other associated risk factors for cardiovascular events, such as cigarette smoking and hypertriglyceridemia, remain to be clarified.

Increased plasma levels of oxysterols, in vivo markers of oxidative stress, in patients with familial combined hyperlipidemia: reduction during atorvastatin and fenofibrate therapy

Familial combined hyperlipidemia (FCHL), the most common inherited disorder of lipid metabolism, is associated with an increased risk of atherosclerosis that is not fully explained by the metabolic disturbances of these patients. Oxidative damage to lipid components accumulating in the plasma of FCHL patients might contribute to explaining this lack of evidence. Cholesterol is one of the preferential targets of oxidation in LDL and this may contribute to setting a proatherogenetic phenotype in FCHL. We investigated plasma oxysterols (7-ketocholesterol and 7beta-hydroxycholesterol) and alpha-tocopherol as in vivo hallmarks of lipid-related oxidative stress. Oxidative stress hallmarks were measured in 45 FCHL patients and 54 sex- and age-matched healthy controls; in FCHL patients, oxidative stress and lipid profile parameters were also assessed in response to lipid-lowering drugs in a 24-week randomized, open-label trial with atorvastatin or fenofibrate. FCHL patients showed markedly increased levels of oxysterols (p < 0.001) and reduced alpha-tocopherol/total lipids (p < 0.001) compared to controls. These differences were independent of the presence of clinical atherosclerosis and persisted after correction for hyperlipidemia. Atorvastatin and fenofibrate significantly improved the lipid profile and caused a comparable decrease in plasma oxysterols, with the normalization of 7-ketocholesterol and a significant reduction of 7beta-hydroxycholesterol (p < 0.001). These drugs also decreased the ratio of alpha-tocopherol/total lipids by more than 30% (p < 0.001). In conclusion, FCHL patients showed increased hallmarks of cholesterol oxidation and decreased levels of alpha-tocopherol/total lipids. Atorvastatin and fenofibrate displayed comparable efficiency in decreasing oxysterols, but they further decreased lipid-corrected alpha-tocopherol levels in plasma. More research work is needed to understand the clinical meaning of these findings, which may help to understand the role of oxidative stress in FCHL and lipid-lowering therapy.

Clinical importance and therapeutic modulation of small dense low-density lipoprotein particles

The National Cholesterol Education Programme Adult Treatment Panel III accepted the predominance of small dense low-density lipoprotein (sdLDL) as an emerging cardiovascular disease (CVD) risk factor. Most studies suggest that measuring low-density lipoprotein (LDL) particle size, sdLDL cholesterol content and LDL particle number provides additional assessment of CVD risk. Therapeutic modulation of small LDL size, number and distribution may decrease CVD risk; however, no definitive causal relationship is established, probably due to the close association between sdLDL and triglycerides and other risk factors (e.g., high-density lipoprotein, insulin resistance and diabetes). This review addresses the formation and measurement of sdLDL, as well as the relationship between sdLDL particles and CVD. The effect of hypolipidaemic (statins, fibrates and ezetimibe) and hypoglycaemic (glitazones) agents on LDL size and distribution is also discussed.

Cardiovascular disease and toxicities related to HIV infection and its therapies

Cardiovascular manifestations of HIV vary according to disease stage, treatment regimen and geographical location. Common cardiac complications of HIV disease in patients off highly active antiretroviral therapy (HAART) include dilated cardiomyopathy, myocarditis, pericardial effusion, endocarditis, pulmonary hypertension and non-antiretroviral drug-related cardiotoxicity. However, with the introduction of HAART that has substantially modified the course of HIV disease by lengthening survival, additional cardiovascular consequences are a result of the metabolic syndrome with a propensity toward hyperlipidaemia and atherosclerotic heart disease. Because most of the world's HIV-infected patients have not been treated with HAART, the principal HIV-associated cardiovascular manifestations of patients off HAART are reviewed and new knowledge about the prevalence, pathogenesis and treatment in the HAART era are emphasised in this review. Exercise, a nonpharmacological approach to treating HAART-associated metabolic syndrome, is also discussed.

Fenofibrate: a novel formulation (Triglide) in the treatment of lipid disorders: a review

Cardiovascular disease is the major cause of mortality worldwide and accounts for approximately 40% of all deaths. Dyslipidemia is one of the primary causes of atherosclerosis and effective interventions to correct dyslipidemia should form an integral component of any strategy aimed at preventing cardiovascular disease. Fibrates have played a major role in the treatment of hyperlipidemia for more than two decades. Fenofibrate is one of the most commonly used fibrates worldwide. Since fenofibrate was first introduced in clinical practice, a major drawback has been its low bioavailability when taken under fasting conditions. Insoluble Drug Delivery-Microparticle fenofibrate is a new formulation that has an equivalent extent of absorption under fed or fasting conditions. In this review, we will discuss the clinical pharmacology of fenofibrate, with particular emphasis on this novel formulation, as well as its lipid-modulating and pleiotropic actions. We will also analyze the major trial that evaluated fibrates for primary and secondary prevention of cardiovascular disease, the safety and efficacy profile of fibrate-statin combination treatment, and the current recommendations regarding the use of fibrates in clinical practice.

Low-density lipoprotein size and cardiovascular risk assessment

A predominance of small, dense low-density lipoproteins (LDL) has been accepted as an emerging cardiovascular risk factor by the National Cholesterol Education Program Adult Treatment Panel III. LDL size seems to be an important predictor of cardiovascular events and progression of coronary heart disease and evidences suggests that both quality (particularly small, dense LDL) and quantity may increase cardiovascular risk. However, other authors have suggested that LDL size measurement does not add information beyond that obtained by measuring LDL concentration, triglyceride levels and HDL concentrations. Therefore, it remains debatable whether to measure LDL particle size in cardiovascular risk assessment and, if so, in which categories of patient. Therapeutic modulation of LDL particle size or number appears beneficial in reducing the risk of cardiovascular events, but no clear causal relationship has been shown, because of confounding factors, including lipid and non-lipid variables. Studies are needed to investigate the clinical significance of LDL size measurements in patients with coronary and non-coronary forms of atherosclerosis; in particular, to test whether LDL size is associated with even higher vascular risk, and whether LDL size modification may contribute to secondary prevention in such patients.

What a Cardiologist Needs to Know About Patients With Human Immunodeficiency Virus Infection

Patient case: A 48-year-old man with human immunodeficiency virus (HIV) infection developed chronic chest pain that started after a bout of pneumonia. He has hypertension and has smoked cigarettes in the past. His current medications include Kaletra and Combivir. His total cholesterol was 331 mg/L, his HDL cholesterol was 27 mg/L, his triglycerides were 935 mg/L, and his LDL cholesterol could not be calculated. How should this patient be evaluated and managed?

Impact of HIV and highly active antiretroviral therapy on leukocyte adhesion molecules, arterial inflammation, dyslipidemia, and atherosclerosis

Highly active antiretroviral therapy (HAART) has greatly extended the lives of people infected with the human immunodeficiency virus (HIV). This reduced risk of early death from opportunistic infections or other sequelae of HIV infection, however, means that other possible causes of death emerge. Myocardial infarction has become a matter of particular concern. Two of the main sources of cardiovascular disease in this population are believed to be vascular inflammation and dyslipidemia. We review the evidence for this hypothesis and discuss the relationship of HIV to vascular inflammation. Current treatment guidelines do not recommend the immediate initiation of HAART unless warranted, potentially allowing long-term, unchecked viral impact on the development of atherosclerosis. Finally, we consider the protease inhibitors traditionally included in HAART regimens and their relationship to the development of dyslipidemia, as well as other classes of antiretrovirals, such as the non-nucleoside reverse transcriptase inhibitors, which might be a better choice for patients with cardiovascular risks. Other strategies, such as pharmacologic, nutritional, and physical activity interventions are discussed. The patients who might benefit most are those in whom the precursors of vascular plaques, such as fatty streak, smooth muscle cell, macrophage, and T-lymphocyte aggregation not yet identified by echocardiographic and biopsy findings have already developed as a result of unchecked viral inflammation and replication.

Les désordres lipidiques des patients atteints d’affections causées par le VIH

Before the availability of protease inhibitors, elevated triglyceride levels were frequently observed in patients with advanced-stage HIV infection. Since the addition of protease inhibitors to combination treatments, metabolic side effects (alterations in distribution of adipose tissue and metabolic disorders combining dyslipidemia, insulin-resistance and glucose intolerance) have been observed in HIV-positive patients receiving these treatments. Reverse transcriptase nucleoside inhibitors also provoke metabolic disorders. Dyslipidemia is defined by an increase in triglyceride levels of varying and sometimes major intensity, either isolated or combined with a more moderate increase in LDL-cholesterol, while HDL-cholesterol levels may decrease or remain unchanged. These metabolic alterations are potentially atherogenic and may explain these patients' increased risk of cardiovascular disorders. Their mechanism is complex and not yet clearly elucidated. The infection, the improvement in patients' general health and immune status, and individual predisposing factors are probably involved. Treatment probably plays a major role, since the different drugs in these two classes show effects of clearly different intensity. In vitro and ex vivo studies suggest that protease inhibitors alter adipocyte differentiation and induce insulin resistance. Reverse transcriptase nucleoside inhibitors modify adipocyte metabolism too, promoting tissue atrophy. Endocrine factors (cortisol and growth hormones) are also likely to have a role in this hypertrophy of adipose, especially visceral, tissue. These metabolic abnormalities result mainly from the effects of the antiretroviral drugs, notably protease inhibitors, on the hepatic lipid metabolism and on tissue sensitivity to insulin. Lipodystrophy contributes to these abnormalities, as does the reduction in cytokine secretion by adipose tissue. Management of these metabolic disorders is based primarily on a change in the drug regimen (administration of the least deleterious combinations), followed by standard dietary measures and, when necessary, lipid-lowering agents.

High Prevalence of Small Dense LDL as an Underestimated Component of Heart Transplantation–Induced Dyslipidemia: Potential Role in Graft Coronary Vasculopathy?

Heart transplantation-induced dyslipidemia is a recognized risk factor for cardiac allograft vasculopathy that affects survival prognosis. Beyond increased lipids, low-density lipoprotein (LDL) size and systemic factors, including glucose intolerance, oxidative stress, and inflammation, must be taken into account as components of the atherosclerotic risk. The aim of this study was to explore the atherogenic profile of heart transplant recipients (HTR) by assessing lipid parameters, glycemia, oxidative stress status, and inflammation in 59 transplant patients (follow-up of 6 +/- 3 years) compared to 20 healthy volunteers. Classical hypercholesterolemia and hypertriglyceridemia were observed in HTR compared to controls, associated with increased apoCIII levels (0.13 +/- 0.6 vs 0.07 +/- 0.03 g/L, P < .01). Mean LDL size was reduced in HTR compared to controls (25.22 +/- 0.72 vs 26.06 +/- 0.54 nm, P < .001) with an abnormally high prevalence (69% vs 0%, P < .001) of small dense LDL (<25.5 nm). Hyperglycemia (7.3 +/- 3 vs 5.4 +/- 0.8 mmol/L, P < .05) and inflammation (high-sensitive CRP: 3.1 +/- 3 vs 1.6 +/- 0.9 mg/L, P < .001) were evidenced in HTR since no difference in oxidative stress parameters was observed. In conclusion, a high prevalence of small dense LDL is an important component of posttransplantation dyslipidemia.

The effects of HIV protease inhibitors on carbohydrate and lipid metabolism

Since the introduction of HIV protease inhibitors (PIs), disorders of glucose and lipid metabolism have emerged. In dissecting out the direct effect on lipid and glucose metabolism, it has become apparent that individual PIs have different effects on metabolism. Some PIs such as indinavir acutely induce insulin resistance. PIs have also been shown to cause other disorders of glucose metabolism, including impairment of insulin secretion and increased endogenous glucose production. Individual PIs also have different effects on lipid metabolism. Ritonavir predominantly increases triglyceride and very low-density lipoprotein cholesterol levels. Limited studies in HIV-negative volunteers suggest that several of the PIs do not increase low-density lipoprotein cholesterol levels. This review examines the direct effects of PIs on glucose and lipid metabolism by assessing prospective studies of HIV-infected and healthy normal volunteers, and in vitro studies.

The effects of HIV protease inhibitors on carbohydrate and lipid metabolism

Since the introduction of HIV protease inhibitors (PIs), disorders of glucose and lipid metabolism have emerged. In dissecting out the direct effect on lipid and glucose metabolism, it has become apparent that individual PIs have different effects on metabolism. Some PIs such as indinavir acutely induce insulin resistance. PIs have also been shown to cause other disorders of glucose metabolism, including impairment of insulin secretion and increased endogenous glucose production. Individual PIs also have different effects on lipid metabolism. Ritonavir predominantly increases triglyceride and very low-density lipoprotein cholesterol levels. Limited studies in HIV-negative volunteers suggest that several of the PIs do not increase low-density lipoprotein cholesterol levels. This review examines the direct effects of PIs on glucose and lipid metabolism by assessing prospective studies of HIV-infected and healthy normal volunteers, and in vitro studies.