Niacin in HIV-infected individuals with hyperlipidemia receiving potent antiretroviral therapy

Nutritional Issues and Positive Living in Human Immunodeficiency Virus/AIDS

Nutritional counseling has been shown to improve dietary intake in individuals with human immunodeficiency virus (HIV)/AIDS. Registered dietitians/nutritionists can individualize diet interventions to optimize effectiveness in treating metabolic consequences of the HIV infection or highly active antiretroviral therapy. Nutrition management for individuals infected with HIV can be helpful in maintaining lean body weight, combating oxidative stress, reducing complications from hyperglycemia and hyperlipidemia, and managing gastrointestinal function. Consideration should be given to including the expertise of a registered dietitian/nutritionist.

Glucagon like peptide-1 receptor agonists may ameliorate the metabolic adverse effect associated with antiretroviral therapy

The number of people living with HIV and AIDS (PLWHA) reached to almost 40 million, half of which are under antiretroviral treatment (ART). Although the introduction of this therapy significantly improved the life span and quality of PLWHA, metabolic complications of these people remains to be an important issue. These metabolic complications include hyperlipidemia, abnormal fat redistribution and diabetes mellitus, which are defined as lipodystrophy syndrome. Glucagon-like peptide-1 (GLP-1) is a neuropeptide secreted from intestinal L cells and recently developed GLP-1 receptor agonists (GLP-1RAs) stimulate insulin secretion, improve weight control and reduce cardiovascular outcomes. This class of drugs may be a valuable medication in the treatment of HIV-associated metabolic adverse effects and extend the life expectancy of patients infected with HIV.

Adverse Effects Associated With Antiretroviral Therapy and Potential Management Strategies

A variety of adverse drug reactions (ADRs) affecting many organ systems may be observed with antiretroviral therapy (ARV), and they can be differentiated into short- and long- term effects, class effects, or individual drug effects. Commonly seen ADRs include dermatological reactions, associated with nonnucleoside reverse transcriptase inhibitors (NNRTIs) and some protease inhibitors (PIs), and gastrointestinal problems, a major side effect of PIs and of some nucleoside reverse transcriptase inhibitors (NRTIs). Metabolic complications are frequently reported in HIV-infected patients on ARV and often coexist. Lipodystrophy, hyperinsulinemia/hyperglycemia, and bone disorders (osteoporosis, osteonecrosis) are mainly associated with PIs, while lactic acidemia/acidosis are primarily a problem of NRTIs. Hyperlipidemia may be caused by almost all PIs, few NRTIs, and NNRTIs. All antiretroviral drug classes may cause both asymptomatic and symptomatic hepatotoxicity, although nevirapine is the agent most implicated in hepatic events. More drug-specific ADRs include nephrotoxicity (indinavir and tenofovir), central nervous system problems (efavirenz), hematological disturbances (zidovudine), and hypersensitivity reactions (abacavir). Anticipation of ADRs may influence a patient’s decision to delay ARV or to choose specific and potentially less active agents. Occurrence of ADRs may significantly impact a patient’s quality of life and drug adherence. Pharmacists counseling HIV-infected patients should be aware of common ADRs with ARV and potential management strategies.

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.

Lipid Management in Human Immunodeficiency Virus

The development and use of antiretroviral medications to treat patients infected with human immunodeficiency virus (HIV) has dramatically changed the course of this disease from one that was fatal to a chronic and more manageable condition. Recommendations and guidelines for the general population are presented in this review with suggestions as to how they may be applied to this patient population. Issues for which there is little or no information available are noted to highlight the many gaps in our knowledge regarding diagnosis and management of dyslipidemia for patients living with HIV.

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.

Lipid management in human immunodeficiency virus

The development and use of antiretroviral medications to treat patients infected with human immunodeficiency virus (HIV) has dramatically changed the course of this disease from one that was fatal to a chronic and more manageable condition. Recommendations and guidelines for the general population are presented in this review with suggestions as to how they may be applied to this patient population. Issues for which there is little or no information available are noted to highlight the many gaps in our knowledge regarding diagnosis and management of dyslipidemia for patients living with HIV.

Current topics in HIV-1 pathogenesis: The emergence of deregulated immuno-metabolism in HIV-infected subjects

HIV-1 infection results in long-lasting activation of the immune system including elevated production of pro-inflammatory cytokine/chemokines, and bacterial product release from gut into blood and tissue compartments, which are not fully restored by antiretroviral therapies. HIV-1 has also developed numerous strategies via viral regulatory proteins to hijack cell molecular mechanisms to enhance its own replication and dissemination. Here, we reviewed the relationship between viral proteins, immune activation/inflammation, and deregulated metabolism occurring in HIV-1-infected patients that ultimately dampens the protective innate and adaptive arms of immunity. Defining precisely the molecular mechanisms related to deregulated immuno-metabolism during HIV-1 infection could ultimately help in the development of novel clinical approaches to restore proper immune functions in these patients.

Extended-Release Niacin Versus Fenofibrate in HIV-Infected Participants With Low High-Density Lipoprotein Cholesterol: Effects on Endothelial Function, Lipoproteins, and Inflammation

BACKGROUND

Low levels of high-density lipoprotein cholesterol (HDL-C) are common in individuals with human immunodeficiency virus (HIV) infection, persist during antiretroviral therapy (ART), and are associated with increased cardiovascular disease (CVD) risk.

METHODS

Virologically controlled participants without CVD on stable ART with low HDL-C (men <40 mg/dL, women <50 mg/dL) and triglycerides >150 mg/dL were randomized to receive open-label extended-release niacin 1500 mg/day with aspirin 325 mg/day or fenofibrate 200 mg/day for 24 weeks. The primary endpoint was the week 24 within-arm change in brachial artery flow-mediated dilation (FMD) in participants with complete follow-up scans.

RESULTS

Of 99 participants, 74 had complete data (35 niacin, 39 fenofibrate). Median age was 45 years, 77% were male, median CD4(+) count was 561 cells/µL, and brachial FMD was 4.2%. Median HDL-C was 32 mg/dL for men and 38 mg/dL for women, low-density lipoprotein cholesterol was 103 mg/dL, and triglycerides were 232 mg/dL. In men, HDL-C increased a median of 3 mg/dL with niacin and 6.5 mg/dL with fenofibrate (P < .001 for both). In women, HDL-C increased a median of 16 mg/dL with niacin and 8 mg/dL with fenofibrate (P = .08 for both). After 24 weeks, there was no significant change in FMD in either arm; the median (interquartile range) change was +0.6% (-1.6 to 2.3) with niacin (P = .28) and +0.5% (-1.0 to 3.0) with fenofibrate (P = .19). Neither treatment significantly affected C-reactive protein, interleukin 6, or D-dimer levels.

CONCLUSIONS

Despite improvements in lipids, niacin or fenofibrate treatment for 24 weeks did not improve endothelial function or inflammatory markers in participants with well-controlled HIV infection and low HDL-C.

CLINICAL TRIALS REGISTRATION

NCT01426438.

Impact of antiretroviral therapy on lipid metabolism of human immunodeficiency virus-infected patients: Old and new drugs

For human immunodeficiency virus (HIV)-infected patients, the 1990s were marked by the introduction of highly active antiretroviral therapy (HAART) representing a new perspective of life for these patients. The use of HAART was shown to effectively suppress the replication of HIV-1 and dramatically reduce mortality and morbidity, which led to a better and longer quality of life for HIV-1-infected patients. Apart from the substantial benefits that result from the use of various HAART regimens, laboratory and clinical experience has shown that HAART can induce severe and considerable adverse effects related to metabolic complications of lipid metabolism, characterized by signs of lipodystrophy, insulin resistance, central adiposity, dyslipidemia, increased risk of cardiovascular disease and even an increased risk of atherosclerosis. New drugs are being studied, new therapeutic strategies are being implemented, and the use of statins, fibrates, and inhibitors of intestinal cholesterol absorption have been effective alternatives. Changes in diet and lifestyle have also shown satisfactory results.

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.

Effect of colesevelam and niacin on low-density lipoprotein cholesterol and glycemic control in subjects with dyslipidemia and impaired fasting glucose

BACKGROUND

Niacin monotherapy in patients with dyslipidemia and impaired fasting glucose (IFG) may result in hyperglycemia. Colesevelam has the unique dual approvals to lower low-density lipoprotein cholesterol (LDL-C) and to improve glycemic control in type 2 diabetes mellitus.

OBJECTIVES

The aim of our study was to evaluate the effect of combined colesevelam and niacin treatment on LDL-C-lowering and glycemic control in subjects with IFG and dyslipidemia.

METHODS

Men or women ≥ 18 years of age, with dyslipidemia (non-high-density lipoprotein cholesterol ≥ 100 mg/dL and ≤ 220 mg/dL; high-density lipoprotein cholesterol < 60 mg/dL) and fasting plasma glucose (FPG) ≥ 90 mg/dL and ≤ 145 mg/dL were randomly assigned 1:1 to colesevelam (3750 mg/d) with niacin titration (n = 70) or placebo with niacin titration (n = 70) over 12 weeks. Niacin was titrated from 500 mg/d up to a maximum of 2000 mg/d as tolerated, and all subjects took enteric-coated aspirin daily. Lipid and glycemic efficacy parameters were assessed as well as safety evaluations of adverse events, vital signs, alanine aminotransferase, aspartate aminotransferase, hematology, and urinalysis.

RESULTS

Adjunct colesevelam had significantly greater LDL-C-lowering effect than niacin alone (placebo); -20.67% vs -12.86%, respectively (P = .0088). Niacin-mediated increases in FPG were significantly less with adjunct colesevelam (1.8 mg/dL vs 6.7 mg/dL; P = .0046), and fewer colesevelam subjects had increases of ≥ 10 mg/dL in FPG (8 vs 17, respectively). Adjunct colesevelam resulted in significantly smaller increases in hemoglobin A1c than placebo (0.06% vs 0.18%, respectively; P = .005). Consistent with hemoglobin A1c and FPG changes, fructosamine levels significantly decreased with colesevelam treatment (-5.0 μmol/L) but increased with placebo (3.0 μmol/L; P =.0255).

CONCLUSIONS

Colesevelam as an adjunct to niacin therapy further lowers LDL-C while obviating the adverse effects of niacin on glucose metabolism in patients with dyslipidemia and IFG.

Nutritional and metabolic correlates of cardiovascular and bone disease in HIV-infected patients

The treatment of HIV infection has dramatically reduced the incidence of AIDS-related illnesses. At the same time, non-AIDS-related illnesses such as cardiovascular and bone disease are becoming more prevalent in this population. The mechanisms of these illnesses are complex and are related in part to the HIV virus, antiretroviral medications prescribed for HIV infection, traditional risk factors exacerbated by HIV, and lifestyle and nutritional factors. Further prospective research is needed to clarify the mechanisms by which HIV, antiretroviral medications, and nutritional abnormalities contribute to bone and cardiovascular disease in the HIV population. Increasingly, it is being recognized that optimizing the treatment of HIV infection to improve immune function and reduce viral load may also benefit the development of non-AIDS-related illnesses such as cardiovascular and bone disease.

Management of the metabolic effects of HIV and HIV drugs

Morphologic and metabolic abnormalities, including subcutaneous adipose tissue wasting, central adipose tissue accumulation, dyslipidemia and disorders of glucose metabolism are common among HIV-infected patients receiving highly active antiretroviral therapy (HAART) and contribute to the risk of cardiovascular disease in this population. The pathogenesis of these disorders is due to complicated interactions between effects of chronic HIV infection, HAART medications and patient factors, including genetic susceptibility. HAART has transformed HIV into a chronic condition for many patients and as a result the majority of HIV-infected patients in many areas of the developed world will soon be aged ≥50 years. Given that metabolic and cardiovascular diseases increase with aging, knowledge of the optimal management of these conditions is essential for practitioners caring for HIV-infected patients, including endocrine subspecialists. This Review highlights the clinical management of these disorders, focusing on the latest evidence regarding the efficacy of treatment strategies, newly available medications and potential interactions between HAART medications and medications used to treat metabolic disorders.

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.

Effect of extended-release niacin on hormone-sensitive lipase and lipoprotein lipase in patients with HIV-associated lipodystrophy syndrome

BACKGROUND

HIV-associated lipodystrophy syndrome is strongly associated with antiretroviral treatment in patients with human immunodeficiency virus (HIV). Niacin is thought to affect hormone-sensitive lipase (HSL) and lipoprotein lipase (LPL) expression in peripheral and intra-abdominal fat (IAF).

OBJECTIVE

This study investigated the effect of extended-release niacin (ERN) on adipose HSL and LPL expression in patients with HIV-associated lipodystrophy syndrome.

METHODS

Changes in IAF and peripheral fat content and HSL and LPL expression were examined in 4 HIV-infected patients recruited from a prospective study treated with ERN. Patients underwent limited 8 slice computerized tomography abdominal scans, dual-energy X-ray absorptiometry scans, and skin punch biopsies of the mid-thigh at baseline and after 12 weeks of ERN. All subjects were on stable highly active antiretroviral therapy prior to and during the study. Changes in body habitus were self-reported.

RESULTS

Normalized HSL expression decreased in 3 patients and normalized LPL expression increased in all 4 patients when comparing pre- and post-ERN treated samples. All subjects showed a decrease in total cholesterol (TC) and triglyceride (TG) levels.

CONCLUSIONS

Preliminary analysis suggests ERN may induce changes in HSL and LPL expression. This method is a feasible approach to identify changes in adipose RNA expression involved with lipolysis.

Lipid metabolism in treated HIV Infection

Patients infected with the human immunodeficiency virus (HIV) are prone to a great number of lipid and lipoprotein disturbances, as a result of both the infection itself and direct effects on lipid metabolism from the drugs used to treat HIV infection. These lipid disorders account for at least part of the increased risk of cardiovascular disease seen in this population. In general, evaluation and interventions for dyslipidemia in HIV-infected individuals should follow guidelines established for the general population. Special consideration, however, must be given to the potential for adverse drug interactions between lipid lowering drugs and the agents used to treat HIV infection. In this review, we summarize what is known about the relative tendency of different antiretroviral drugs to alter lipid levels, and suggest an approach to intervention for dyslipidemia in this population.

Lipodystrophy: pathophysiology and advances in treatment

Lipodystrophy is a medical condition characterized by complete or partial loss of adipose tissue. Not infrequently, lipodystrophy occurs in combination with pathological accumulation of adipose tissue at distinct anatomical sites. Patients with lipodystrophy exhibit numerous metabolic complications, which indicate the importance of adipose tissue as an active endocrine organ. Not only the total amount but also the appropriate distribution of adipose tissue depots contribute to the metabolic state. Genetic and molecular research has improved our understanding of the mechanisms underlying lipodystrophy. Circulating levels of hormones secreted by the adipose tissue, such as leptin and adiponectin, are greatly reduced in distinct subpopulations of patients with lipodystrophy. This finding rationalizes the use of these adipokines or of agents that increase their circulating levels, such as peroxisome proliferator-activated receptor γ (PPARγ) agonists, for therapeutic purposes. Other novel therapeutic approaches, including the use of growth hormone and growth-hormone-releasing factors, are also being studied as potential additions to the therapeutic armamentarium. New insights gained from research and clinical trials could potentially revolutionize the management of this difficult-to-treat condition.

Assessment and modification of cardiovascular disease risk in the HIV-infected individual

HIV-infected patients are living decades longer than before owing to combination antiretroviral therapy. However, complications are emerging in this population at rates higher than the general population, including cardiovascular disease (CVD). HIV-infected patients have many traditional risk factors that account for a significant part of their increased risk of CVD. However, HIV factors, including complications from antiretroviral therapy and increased inflammation associated with chronic HIV infection, also play a role. Clinicians need to be ever-vigilant to calculate and help attenuate any modifiable CVD risk factors for each HIV-infected individual.

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.

Markers of atherosclerosis and inflammation and mortality in patients with HIV infection

OBJECTIVE

HIV-infected patients are at increased risk for cardiovascular disease, which may be mediated in part by inflammation. Surrogate marker studies suggest an increased prevalence of vascular abnormalities in HIV infection. We examined the association of all-cause mortality in HIV-infected patients with carotid artery intima-media thickness (cIMT) and high-sensitivity C-reactive protein (hsCRP).

DESIGN AND METHODS

Baseline risk factors, cIMT and hsCRP were prospectively measured in 327 HIV-infected participants. Follow-up time with median of 3.1 years was calculated from baseline to death or censored dated 7/31/07. Cox Proportional Hazards models were used to study risk factors associated with mortality.

RESULTS

Thirty-eight (11.6%) of participants have died since study enrollment. cIMT was significantly higher in those who died and decedents were significantly more likely to have cIMT above the 75th percentile. Those who died had higher hsCRP than those alive and more had hsCRP values above 3mg/L. CD4 count was lower and log(10) viral load was higher in decedents, but antiretroviral regimens were similar in both groups. cIMT and hsCRP levels were significantly associated with mortality (HR = 2.74, 95% CI 1.26-5.97, p = 0.01; HR = 2.38, 95% CI 1.15-4.9, p = 0.02).

CONCLUSIONS

Our study demonstrated a strong association of carotid IMT and hsCRP with all-cause death in this HIV-infected population despite being similar with respect to exposure to antiretroviral medications. Together these surrogate markers may be indices of chronic inflammation and unfavorable outcomes in HIV-positive patients.

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.

Insulin resistance and diabetes mellitus associated with antiretroviral use in HIV-infected patients: pathogenesis, prevention, and treatment options

The contribution of current antiretroviral treatment regimens to the long-term survival of HIV-infected individuals is accompanied by increased risk of glucose metabolism abnormalities in this patient population. The risk of insulin resistance and diabetes in HIV-infected patients receiving antiretroviral treatment stems from 2 sources: exposure to the same environmental factors that have led to an increased incidence of these conditions in the general population and the negative effects on glucose metabolism inherent to components of antiretroviral treatment regimens. This article reviews the pathogenesis and diagnosis of insulin resistance and diabetes and the contribution of components of antiretroviral therapy regimens to increased risk for these conditions. Optimization of antiretroviral treatment regimens for HIV-infected patients with or at increased risk for development of abnormalities in glucose metabolism is discussed.

A multimodal, evidence-based approach to achieve lipid targets in the treatment of antiretroviral-associated dyslipidemia: case report and review of the literature

Metabolic abnormalities associated with the treatment of human immunodeficiency virus (HIV) infection are well-recognized problems that increase cardiovascular risk. As a result of the complexity of treating both HIV- and antiretroviral-related comorbidities, strategies that improve adverse drug events while maintaining viral control are in critical need. Although guidelines have somewhat helped in the general approach and in first-line strategies for managing dyslipidemia in patients receiving antiretrovirals, a paucity of data exist to guide clinicians in treating patients whose conditions are refractory to first-line options or who are at substantial risk for cardiovascular events. Further complicating the choice of lipid-lowering strategy is the lack of randomized controlled data from the HIV-affected population and a concern about clinically significant drug-drug interactions. We describe an HIV-infected patient with efavirenz-associated dyslipidemia at very high cardiovascular risk who had not achieved his primary or secondary lipid goals despite 2 years of treatment in a lipid specialty clinic. Lipid control was accomplished in 10 weeks with a targeted, stepwise approach of switching efavirenz to nevirapine, followed by rosuvastatin 20 mg/day, which was sustained for at least 10 months. Of most importance, this outcome was achieved without any clinically significant alteration in virologic or immunologic control. This case report highlights the potential for a pharmacist-guided, multistep approach that addresses HIV-related dyslipidemia and incorporates the pharmacokinetic literature to guide lipid-lowering therapy and promote the attainment of goals based on current standards of care.

Effects of niacin on glucose control in patients with dyslipidemia

Niacin (nicotinic acid), the most effective available pharmacotherapy for increasing high-density lipoprotein cholesterol, also lowers triglycerides and hence may be useful, alone or in combination with hydroxymethylglutaryl coenzyme A reductase inhibitors (statins), to offset residual cardiovascular risk in patients with mixed or diabetic dyslipidemia. We conducted a review of published consensus guidelines since 2000 and an English-language PubMed search of prospective, randomized controlled trials and open-label studies from January 1, 1990, through December 31, 2007, concerning the effects of niacin, alone or in combination with statins, on glycemic regulation in dyslipidemic patients (with or without diabetes mellitus). For search terms, we used the title words niacin or nicotinic acid and key words including diabetes, diabetic, dyslipidemia, glucose, glycemic, HbA1c, hemoglobin, hyperglycemia, human, insulin, postprandial, and safety. Retrospective and observational studies, case reports, and case studies were excluded. On the basis of our analysis, the effects of niacin (< or =2.5 g/d), alone or in combination with statins, on fasting glucose (an increase of 4%-5%) and hemoglobin A1c levels (an increase of < or =0.3%) are modest, transient or reversible, and typically amenable to adjustments in oral hypoglycemic regimens without discontinuing niacin. Niacin therapy was infrequently associated with incident diabetes or the need for new insulin prescriptions. Studies showed important clinical benefits of niacin or niacin-statin regimens despite modest effects on glucose control. On a population basis, significant reductions in incidences of cardiovascular events and the degree of atherosclerotic progression associated with long-term niacin (or niacin-statin) therapy in patients with diabetic dyslipidemia outweigh the typically mild effects of this therapy on glycemic regulation. Consensus guidelines recommend monitoring glycemic control after initiating niacin treatment or increasing its dosage.

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.

Metabolic effects of protease inhibitor-sparing antiretroviral regimens given as initial treatment of HIV-1 Infection (AIDS Clinical Trials Group Study A5095)

OBJECTIVE

To assess metabolic changes after initiation of protease inhibitor (PI)-sparing regimens in antiretroviral-naive patients.

METHODS

Metabolic changes were analyzed within the triple-nucleoside (zidovudine [ZDV]/lamivudine [3TC]/abacavir [ABC])-containing, 3-drug efavirenz (EFV) [ZDV/3TC + EFV]-containing, and 4-drug EFV [ZDV/3TC/ABC + EFV]-containing arms of the AIDS Clinical Trials Group multicenter trial A5095. Metabolic values were compared with published US general population norms.

RESULTS

From week 0 to week 24, all arms exhibited similar mild median increases in glucose and decreases in insulin sensitivity, whereas changes in lipids were greater in the ZDV/3TC + EFV and ZDV/3TC/ABC + EFV arms than in the ZDV/3TC/ABC arm: triglyceride (TG; 7, 18, and -1 mg/dL, respectively), total cholesterol (TC; 23, 28, and 5 mg/dL, respectively), low-density lipoprotein cholesterol (LDL-C; 9, 14, and 1 mg/dL, respectively), and high-density lipoprotein cholesterol (HDL-C; 10, 10, and 5 mg/dL, respectively). Adjusted mean study lipid values of all study participants at week 0 and week 96 compared with those of the National Health and Nutrition Examination Survey (NHANES) 1999 through 2002 values were: TG (148, 187, and 123 mg/dL, respectively), TC (164, 195, and 203 mg/dL, respectively), HDL-C (35, 47, and 51 mg/dL, respectively), and LDL-C (101, 117, and 123 mg/dL, respectively) (P < or = 0.005 for each value vs. NHANES values).

CONCLUSIONS

Similar mild increases in glucose and decreases in insulin sensitivity were observed in all regimens, whereas lipids were modestly higher in the EFV-containing arms. Compared with general population norms, the metabolic dysfunctions of concern after these PI-sparing therapies were increasingly abnormal TC and lower (but improved relative to baseline) HDL-C levels.

Alteraciones lipídicas y riesgo cardiovascular asociado a la terapia antirretroviral

Dyslipidemia is common in HIV-infected patients receiving antiretroviral therapy (ART) and it is often associated with the use of specific antiretroviral drugs. The phenotypic profile can include elevated triglycerides or cholesterol alone, or mixed patterns with varying changes in LDL and HDL lipoproteins, which imply different levels of cardiovascular risk. Growing evidence indicates that ART-associated hyperlipidemia accelerates the development of atherosclerosis and coronary heart disease in HIV-infected patients. In recent years, a number of retrospective database reviews and prospective cohort studies have reported a higher incidence of coronary events in patients receiving ART, which seems to be closely related with the presence of dyslipidemia and the duration of exposure to ART. Although the clinical benefit of treating ART-related dyslipidemia remains unproven, most experts recommend a policy of cardiovascular disease prevention and management similar to that used in non-HIV-infected individuals. In addition, the use of antiretrovirals associated with a more favorable lipid profile is considered. Clinical experience with lipid-lowering therapy in HIV-infected patients is still limited, but there is increasing data confirming its efficacy and safety in this setting. Drug interactions should be taken into account when statins are used in patients receiving protease inhibitors.

Metabolic abnormalities in HIV-infected patients: An update

In recent years, substantial progress has been made in our understanding of the pathogenesis, risk factors, and treatment of glucose and lipid abnormalities in HIV-infected patients. Newer antiretrovirals, such as abacavir and tenofovir in the nucleoside reverse transcriptase class and atazanavir in the protease inhibitor class, have been shown to improve metabolic profiles compared to other medications. In addition, new information regarding the efficacy of glucose and lipid-lowering medications in HIV-infected patients has become available. It has also been demonstrated that aggressive risk factor modification can reduce the burden of cardiovascular disease in this population. This article reviews these recent advances in order to help providers respond to these important clinical challenges.

Improved triglycerides and insulin sensitivity with 3 months of acipimox in human immunodeficiency virus-infected patients with hypertriglyceridemia

CONTEXT

Metabolic abnormalities such as hypertriglyceridemia remain a challenge for optimizing long-term health in HIV-infected patients.

OBJECTIVE

Elevation of free fatty acids (FFAs) may contribute to hyperlipidemia and insulin resistance in HIV. We evaluated the efficacy and safety of chronic inhibition of lipolysis in HIV-infected men and women with hypertrigyceridemia. We hypothesized that acipimox would lead to significant reductions in triglycerides and improved insulin sensitivity, compared with placebo.

DESIGN

A 3-month, randomized, double-blind, controlled trial of acipimox (250 mg thrice daily) vs. placebo was conducted in 23 HIV-infected men and women with hypertriglyceridemia (>150 mg/dl), abnormal fat distribution, and no current lipid-lowering therapy. The primary outcome variable was triglyceride concentration, and insulin sensitivity measured by hyperinsulinemic euglycemic clamp was a secondary outcome.

SETTING

The study was conducted at an academic medical center.

RESULTS

Acipimox resulted in significant reductions in FFAs [mean change -0.38 (0.06) vs. 0.08 (0.06) mEq/liter with placebo, -68 vs. +17% change from mean baseline, P < 0.0001], decreased rates of lipolysis (P < 0.0001), and a median triglyceride decrease from 238 mg/dl at baseline to 190 mg/dl, compared with an increase from 290 to 348 mg/dl in the placebo group (P = 0.01). Acipimox improved insulin sensitivity [acipimox +2.31 (0.74) vs. placebo -0.21 (0.90) mg glucose per kilogram lean body mass per minute, or +31 vs. -2% change from mean baseline values, P = 0.04]. Improvements in insulin sensitivity were significantly correlated with reductions in FFAs (r = -0.62, P = 0.003) and lipolysis (r = -0.59, P = 0.005).

CONCLUSIONS

Acipimox resulted in significant sustained reductions in lipolysis, improved glucose homeostasis, and significant but modest reductions in triglycerides in HIV-infected individuals with abnormal fat distribution and hypertriglyceridemia. Improvement in overall metabolic profile with acipimox suggests a potential clinical utility for this agent that requires further investigation.

Safety and Efficacy of Extended-Release Niacin for the Treatment of Dyslipidaemia in Patients with HIV Infection: Aids Clinical Trials Group Study A5148

Background

Dyslipidaemia is very common in patients with HIV infection, but current therapies are often suboptimal. Since niacin may cause insulin resistance and hepatotoxicity, it has generally been avoided in this setting.

Methods

Non-diabetic male subjects ( n=33) who had well-controlled HIV infection on antiretroviral therapy, fasting triglycerides ≥2.26 mmol/l and non-high density lipoprotein cholesterol (non-HDL-C) ≥4.66 mmol/l received escalating doses of extended-release niacin (ERN) up to 2,000 mg nightly for up to 44 weeks.

Results

Fourteen subjects (42%) had pre-diabetes at entry. Twenty-three subjects (70%) received the maximum dose, eight (24%) received 1,500 mg. Niacin was well-tolerated. Only four subjects (12%) discontinued study treatment. There were small increases in fasting glycaemia and insulin resistance estimated by the homeostasis model assessment, but insulin resistance measures from the 2-h oral glucose tolerance test only transiently worsened. No subject developed persistent fasting hyperglycaemia; one had persistently elevated 2-h glucose >11.1 mmol/l. There were no significant changes in serum transaminases or uric acid. At week 48, the median change in fasting lipid levels in mmol/l (interquartile range) were: total cholesterol -0.21 (-1.35, -0.05), HDL-C +0.013 (-0.03,+0.28), non-HDL-C -0.49 (-1.37, +0.08) and triglycerides -1.73 (-3.68, -0.72). Favourable changes in large HDL and large very low density lipoprotein particle concentration were observed by nuclear magnetic resonance spectroscopy.

Conclusions

ERN in doses up to 2,000 mg daily was safe, well-tolerated and efficacious in HIV-infected subjects with atherogenic dyslipidaemia. Increases in glycaemia and insulin resistance tended to be transient.

Current concepts in the diagnosis and management of metabolic complications of HIV infection and its therapy

Changes in fat distribution, dyslipidemia, disordered glucose metabolism, and lactic acidosis have emerged as significant challenges to the treatment of human immunodeficiency virus (HIV) infection. Over the past decade, numerous investigations have been conducted to better define these conditions, identify risk factors associated with their development, and test potential therapeutic interventions. The lack of standardized diagnostic criteria, as well as disparate study populations and research methods, have led to conflicting data regarding the diagnosis and treatment of metabolic and body shape disorders associated with HIV infection. On the basis of a review of the medical literature published and/or data presented before April 2006, we have prepared a guide to assist the clinician in the detection and management of these complications.

Heart positive: design of a randomized controlled clinical trial of intensive lifestyle intervention, niacin and fenofibrate for HIV lipodystrophy/dyslipidemia

Dyslipidemia and insulin resistance occur in a large proportion of HIV-infected patients treated with highly active antiretroviral therapy (HAART); anthropomorphic changes, such as lipoatrophy and central obesity, occur in a subset of patients. This cluster of clinical features, which is termed HIV lipodystrophy, places patients at increased risk for cardiovascular disease. Currently, there is no consensus on the appropriate therapy for the management of HIV lipodystrophy for which the underlying defects are enhanced lipolysis, impaired fat oxidation, increased hepatic VLDL-triglyceride synthesis and secretion, and impaired disposal of intestinally-derived lipoprotein-triglycerides. We describe the design of a randomized, placebo-controlled trial to compare the effects of usual care to diet, exercise and lipid-lowering drugs on lipid profiles of patients with HIV lipodystrophy. The trial will randomize 200 patients into five groups. Outcomes of usual care, diet and exercise alone or in combination with niacin, fenofibrate or both medications will be compared after six months. Unique aspects of the design include an interactive Internet Diet Management system to increase ATP-III recommended dietary compliance for metabolic syndrome, and a supervised program of aerobic and resistance exercises. The study is powered to detect a 20% decrease in triglycerides with the lifestyle intervention and an additional 20% improvement with the addition of niacin and/or fenofibrate. Secondary outcomes include assessment of lipid profile changes, LDL and HDL particle size, plasma cholesterol ester transport protein activity, visceral and subcutaneous fat distribution, glucose tolerance, insulin resistance, and leptin and adiponectin levels.

Coronary heart disease in HIV-infected patients

Increased risk of coronary heart disease has emerged as a long-term concern among HIV-infected patients receiving antiretroviral therapy. HIV-infected patients may have modifiable risk factors for heart disease that are associated with HIV itself, antiretroviral therapy, or factors unrelated to HIV. Dyslipidemia, insulin resistance, and diabetes mellitus are often multifactorial in origin. Patients with lipodystrophy frequently have a constellation of metabolic changes that may predispose them to accelerated atherosclerosis. There is also concern about contributions of chronic inflammation and prothrombotic tendencies in the pathogenesis of coronary heart disease in the HIV-infected population. Several epidemiological studies support an increased relative risk of myocardial infarction in HIV-infected patients on highly active antiretroviral therapy. Although absolute risk appears low in the short term, patients may accrue significant risk over time. Clinicians are advised to assess coronary heart disease risk in HIV-infected patients and to intervene to reduce the impact of modifiable risk factors.

Body shape, lipid, and cardiovascular complications of HIV therapy

Metabolic complications of HIV therapy have emerged as a vexing problem for individuals living with HIV infection and their clinicians. These adverse effects threaten health and quality of life as well as adherence to HIV treatment. Among the most common metabolic complications confronting clinicians are body shape changes and dyslipidemia. The pathogenesis of these disorders remains elusive, challenging the development of treatment strategies particularly for fat redistribution. Switching from metabolically offensive antiretrovirals has yielded improvements in both body shape and dyslipidemia. In addition, therapeutic approaches that have been developed for the treatment of dyslipidemia in HIV-uninfected patients, can with important caveats be applied to HIV therapy-associated lipid disorders. Aggressive assessment of cardiovascular disease risk and intervention is likely to reduce the incidence of cardiovascular disorders in HIV-infected patients. Development of antiretrovirals with fewer metabolic adverse effects will reduce the incidence of these and similar disorders during HIV therapy.

Treatment of dyslipidaemia in HIV-infected persons

Accumulating evidence suggests that HIV-infected individuals have an increased risk of cardiovascular events. This risk seems to be at least partially mediated by dyslipidaemia, which is related to the use of highly active antiretroviral therapy (HAART). As HIV-infected individuals live longer due to HAART, their cardiovascular risk will invariably increase. Because HAART is likely to be used indefinitely, HAART-related dyslipidaemia has emerged as a major cardiovascular concern. This article summarises the evaluation of dyslipidaemia and cardiovascular risk in HIV-infected individuals, the potential pathophysiological and genetic mechanisms involved in HAART-related dyslipidaemia and the current treatment approaches. In general, dyslipidaemia is evaluated and treated as in HIV-negative persons. The first step is cardiovascular risk assessment and the determination of target lipid levels. A healthier lifestyle and, in particular, smoking cessation should be promoted. Lowering levels of low-density lipoprotein cholesterol (or, in the setting of significant hypertriglyceridaemia, non-high-density lipoprotein cholesterol) is the primary target of intervention. Switching HAART to a more lipid-favourable regimen should be considered if this does not jeopardise virological control. Many patients will need lipid-lowering drug therapy. Appropriate low-density lipoprotein cholesterol target levels may be more difficult to reach than in the HIV-negative population, and the potential for drug interactions when using lipid-lowering agents together with HAART needs to be considered. The identification of HAART strategies with no or minimal metabolic toxicity, and the identification of the safest and most efficacious lipid-lowering therapies for HIV-infected individuals with dyslipidaemia are important research goals.