Effects of pravastatin on lipoproteins and endothelial function in patients receiving human immunodeficiency virus protease inhibitors

Statin Therapy and Flow-Mediated Dilation: A Systematic Review and Dose-Response Meta-Analysis Using the GRADE of Data from Randomized Controlled Trials

INTRODUCTION

A previous meta-analysis reported the positive effects of statin therapy on endothelial function. However, the obtained result had several limitations that necessitated updating the information in this field. Therefore, a systematic and meta-analysis review was conducted to determine whether statin therapy could improve endothelial function, as assessed by flow-- mediated dilation (FMD).

METHODS

MEDLINE, SciVerse Scopus, and Clarivate Analytics Web of Science were searched to identify randomized placebo-controlled trials assessing the impact of statin therapy on FMD. A random-effects model was used for meta-analysis to calculate the mean difference in weight. Meta- regression and subgroup analyses were used to identify sources of heterogeneity. In addition, nonlinear dose-response, quality of evidence, influence analysis, and publication bias evaluation were assessed using standard methods.

RESULT

Thirty-five trials (41 arms) involving 2178 participants were included in the meta-analysis study. Statin treatment significantly improved FMD [weighted mean difference (WMD): 1.7%, 95% CI: 1.3-2.2, p < 0.001). However, significant heterogeneity was observed (I2=97.9%, p < 0.001). The results of the subgroup analysis showed that health status can contribute to heterogeneity. Non-linear dose-response analysis revealed the most significant improvement in FMD with atorvastatin at a dose of 20 mg/day and simvastatin at 80 mg/day.

CONCLUSION

Statin therapy significantly improved endothelial function, as assessed by FMD. These changes are clinically significant, but their use should be approached with caution.

Pravastatin for lowering lipids

BACKGROUND

A detailed summary and meta-analysis of the dose-related effect of pravastatin on lipids is not available.

OBJECTIVES

Primary objective To assess the pharmacology of pravastatin by characterizing the dose-related effect and variability of the effect of pravastatin on the surrogate marker: low-density lipoprotein (LDL cholesterol). The effect of pravastatin on morbidity and mortality is not the objective of this systematic review. Secondary objectives • To assess the dose-related effect and variability of effect of pravastatin on the following surrogate markers: total cholesterol; high-density lipoprotein (HDL cholesterol); and triglycerides. • To assess the effect of pravastatin on withdrawals due to adverse effects.

SEARCH METHODS

The Cochrane Hypertension Information Specialist searched the following databases for randomized controlled trials (RCTs) up to September 2021: CENTRAL (2021, Issue 8), Ovid MEDLINE, Ovid Embase, Bireme LILACS, the WHO International Clinical Trials Registry Platform, and ClinicalTrials.gov. We also contacted authors of relevant papers regarding further published and unpublished work. The searches had no language restrictions.

SELECTION CRITERIA

Randomized placebo-controlled trials evaluating the dose response of different fixed doses of pravastatin on blood lipids over a duration of three to 12 weeks in participants of any age with and without evidence of cardiovascular disease.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed eligibility criteria for studies to be included, and extracted data. We entered lipid data from placebo-controlled trials into Review Manager 5 as continuous data and withdrawal due to adverse effects (WDAEs) data as dichotomous data. We searched for WDAEs information from all trials. We assessed all trials using Cochrane's risk of bias tool under the categories of sequence generation, allocation concealment, blinding, incomplete outcome data, selective reporting, and other potential biases.

MAIN RESULTS

Sixty-four RCTs evaluated the dose-related efficacy of pravastatin in 9771 participants. The participants were of any age, with and without evidence of cardiovascular disease, and pravastatin effects were studied within a treatment period of three to 12 weeks. Log dose-response data over the doses of 5 mg to 160 mg revealed strong linear dose-related effects on blood total cholesterol and LDL cholesterol, and a weak linear dose-related effect on blood triglycerides. There was no dose-related effect of pravastatin on blood HDL cholesterol. Pravastatin 10 mg/day to 80 mg/day reduced LDL cholesterol by 21.7% to 31.9%, total cholesterol by 16.1% to 23.3%,and triglycerides by 5.8% to 20.0%. The certainty of evidence for these effects was judged to be moderate to high. For every two-fold dose increase there was a 3.4% (95% confidence interval (CI) 2.2 to 4.6) decrease in blood LDL cholesterol. This represented a dose-response slope that was less than the other studied statins: atorvastatin, rosuvastatin, fluvastatin, pitavastatin and cerivastatin. From other systematic reviews we conducted on statins for its effect to reduce LDL cholesterol, pravastatin is similar to fluvastatin, but has a decreased effect compared to atorvastatin, rosuvastatin, pitavastatin and cerivastatin. The effect of pravastatin compared to placebo on WADES has a risk ratio (RR) of 0.81 (95% CI 0.63 to 1.03). The certainty of evidence was judged to be very low.

AUTHORS' CONCLUSIONS

Pravastatin lowers blood total cholesterol, LDL cholesterol and triglyceride in a dose-dependent linear fashion. This review did not provide a good estimate of the incidence of harms associated with pravastatin because of the lack of reporting of adverse effects in 48.4% of the randomized placebo-controlled trials.

A Systematic Review and Meta-Analysis on the Impact of Statin Treatment in HIV Patients on Antiretroviral Therapy

The rate of new human immunodeficiency virus (HIV) infections globally is alarming. Although antiretroviral therapy (ART) improves the quality of life among this group of patients, ARTs are associated with risk of cardiovascular diseases (CVD). Moreover, virally suppressed patients still experience immune activation associated with HIV migration from reservoir sites. Statins are widely recommended as therapeutic agents to control ART-related CVD; however, their impacts on the cluster of differentiation (CD)4 count and viral load are inconsistent. To assess the effect of statins on markers of HIV infections, immune activation and cholesterol, we thoroughly reviewed evidence from randomised controlled trials. We found 20 relevant trials from three databases with 1802 people living with HIV (PLHIV) on statin-placebo treatment. Our evidence showed no significant effect on CD4 T-cell count standardised mean difference (SMD): (-0.59, 95% confidence intervals (CI): (-1.38, 0.19), p = 0.14) following statin intervention in PLHIV on ART. We also found no significant difference in baseline CD4 T-cell count (SD: (-0.01, 95%CI: (-0.25, 0.23), p = 0.95). Our findings revealed no significant association between statins and risk of viral rebound in PLHIV with undetectable viral load risk ratio (RR): (1.01, 95% CI: (0.98, 1.04), p = 0.65). Additionally, we found a significant increase in CD8⁺CD38⁺HLA-DR⁺ T-cells (SMD (1.10, 95% CI: (0.93, 1.28), p < 0.00001) and CD4⁺CD38⁺HLA-DR⁺ T-cells (SMD (0.92, 95% CI: (0.32, 1.52), p = 0.003). Finally, compared to placebo, statins significantly reduced total cholesterol (SMD: (-2.87, 95% CI: (-4.08, -1.65), p < 0.0001)). Our results suggest that the statin lipid-lowering effect in PLHIV on ART may elevate immune activation without influencing the viral load and CD4 count. However, due to the limited evidence synthesised in this meta-analysis, we recommend that future powered trials with sufficient sample sizes evaluate statins' effect on CD4 count and viral load, especially in virally suppressed patients.

Effectiveness and safety of statins on outcomes in patients with HIV infection: a systematic review and meta-analysis

Statins are hypolipidaemic in human immunodeficiency virus (HIV) positive individuals. However, their effect on all-cause mortality and rate of discontinuation is unclear. We conducted a systematic review to evaluate the impact of statins on all-cause mortality, discontinuation rates, and risk of adverse effects among HIV patients on highly active antiretroviral therapy (HAART). We searched four electronic databases from inception until October 2021 for trials and cohort studies evaluating the effects of statin treatment versus placebo in HIV patients. Forty-seven studies involving 91,594 patients were included. Statins were associated with significantly lower risk of discontinuation (RR, 0.701; 95% CI 0.508-0.967; p = 0.031). The risk of all-cause mortality (RR, 0.994; 95% CI 0.561-1.588; p = 0.827), any adverse effects (RR, 0.780; 95% CI 0.564-1.077; p = 0.131) and, diabetes mellitus (RR, 0.272; 95% CI 0.031-2.393; p = 0.241) with statin treatment were lower but not statistically significant compared to placebo/control. Statin treatment was associated with a trend of higher but statistically insignificant risk of myalgia (RR, 1.341; 95% CI 0.770-2.333; p = 0.299), elevated creatine kinase (RR, 1.101; 95% CI 0.457-2.651; p = 0.830) and liver enzyme activities (RR, 1.709; 95% CI 0.605-4.831; p = 0.312). Clinicians should consider the nocebo effect in the effective management of PLWH on statins, who present with common adverse effects such as myalgia and, elevated levels of creatine kinase and liver enzymes.

The Effect of Atorvastatin + Aspirin on the Endothelial Function Differs with Age in Patients with HIV: A Case-Control Study

BACKGROUND

Patients with HIV are more likely to present with cardiovascular disease when compared to the general population.

OBJECTIVE

This was a case-control study that aimed to assess which factors were associated with a reduction in the carotid intima-media thickness (IMT) and an increase in the brachial artery flow-mediated dilation (FMD) in HIV patients who received atorvastatin + aspirin during a period of 6 months.

METHODS

A secondary analysis of a clinical trial was conducted, which included people living with HIV infection and low cardiovascular risk. A total of 38 patients allocated to the intervention arm and treated for 6 months with a combination of atorvastatin + aspirin were included. All participants underwent a carotid and brachial artery ultrasound, both at the beginning and the end of the study. Cases that responded with an increase of >10% of the brachial dilatation (FMD) and reduction of the carotid intima-media thickness (IMT) were considered cases, and those who did not respond were considered controls. We assessed the factors associated with the positive responses obtained through IMT and FMD.

RESULTS

A reduction in the IMT was not significantly associated with any of the evaluated risk factors: age (p=0.211), gender (p=0.260), smoking (p=0.131) or time since HIV diagnosis (p=0.836). An increase in the FMD was significantly associated with age amongst those in the 40-59 age group, p = 0.015 (OR = 4.37; 95% CI: 1.07-17.79).

CONCLUSIONS

Older individuals were more likely to present with an increased FMD after 6 months of treatment with atorvastatin + aspirin.

Effects of HIV Infection on Arterial Endothelial Function: Results From a Large Pooled Cohort Analysis

OBJECTIVE

To determine the effects of HIV serostatus and disease severity on endothelial function in a large pooled cohort study of people living with HIV infection and HIV- controls. Approach and Results: We used participant-level data from 9 studies: 7 included people living with HIV (2 treatment-naïve) and 4 had HIV- controls. Brachial artery flow-mediated dilation (FMD) was measured using a standardized ultrasound imaging protocol with central reading. After data harmonization, multiple linear regression was used to examine the effects of HIV- serostatus, HIV disease severity measures, and cardiovascular disease risk factors on FMD. Of 2533 participants, 986 were people living with HIV (mean 44.4 [SD 11.8] years old) and 1547 were HIV- controls (42.9 [12.2] years old). The strongest and most consistent associates of FMD were brachial artery diameter, age, sex, and body mass index. The effect of HIV+ serostatus on FMD was strongly influenced by kidney function. In the highest tertile of creatinine (1.0 mg/dL), the effect of HIV+ serostatus was strong (β=-1.59% [95% CI, -2.58% to -0.60%], P=0.002), even after covariate adjustment (β=-1.36% [95% CI, -2.46% to -0.47%], P=0.003). In the lowest tertile (0.8 mg/dL), the effect of HIV+ serostatus was strong (β=-1.90% [95% CI, -2.58% to -1.21%], P<0.001), but disappeared after covariate adjustment. HIV RNA viremia, CD4+ T-cell count, and use of antiretroviral therapy were not meaningfully associated with FMD.

CONCLUSIONS

The significant effect of HIV+ serostatus on FMD suggests that people living with HIV are at increased cardiovascular disease risk, especially if they have kidney disease.

Safety and Impact of Low-dose Methotrexate on Endothelial Function and Inflammation in Individuals With Treated Human Immunodeficiency Virus: AIDS Clinical Trials Group Study A5314

BACKGROUND

Chronic inflammation in treated HIV infection is associated with mortality and atherosclerotic cardiovascular disease (ASCVD). We evaluated the safety and potential efficacy of low-dose methotrexate (LDMTX) in treated HIV.

METHODS

This was a phase 2 randomized, double-blind, multicenter trial in adults ≥40 years old with treated HIV, with CD4+ T-cell count ≥400 cells/μL and with/at increased risk for ASCVD. Participants received LDMTX (5-15 mg/week) or placebo (plus folic acid) for 24 weeks and were followed for an additional 12 weeks. Primary endpoints were safety and brachial artery flow-mediated dilation (FMD).

RESULTS

The 176 participants (90% male) had a median (Q1, Q3) age of 54 (49, 59) years. LDMTX was associated with decreases in CD4+ T cells at week 24 and CD8+ T cells at weeks 8, 12, and 24. Eleven participants (12.8%) experienced safety events in the LDMTX group vs 5 (5.6%) in placebo (Δ = 7.2%, upper 1-sided 90% CI, 13.4%; Pnoninferiority = .037). Week 24 change in FMD was 0.47% with LDMTX and 0.09% with placebo (P = .55). No inflammatory markers changed differentially with LDMTX compared to placebo.

CONCLUSIONS

Adults with HIV and increased ASCVD risk treated with LDMTX had more safety events than with placebo, but the prespecified noninferiority margin of 15% was not exceeded. LDMTX had no significant effect on endothelial function or inflammatory biomarkers but was associated with a significant decrease in CD8+ T cells. The balance of risks and potential benefits of LDMTX in this population will require additional investigation.

CLINICAL TRIALS REGISTRATION

NCT01949116.

Association between statin use, atherosclerosis, and mortality in HIV-infected adults

BACKGROUND

While HIV infection is associated with increased cardiovascular risk, benefit from statin is not well established in HIV-infected adults. We assessed whether statins are associated with a decrease in carotid artery intima-media thickness (cIMT) progression and all-cause mortality in HIV-infected adults who are at elevated ASCVD risk and recommended for statins.

METHODS

Carotid IMT was measured at baseline and follow-up in 127 HIV-infected adults who meet ACC/AHA criteria to be on statins. Inverse probability of treatment weighting (IPTW) was used to address selection bias. Multivariable models were used to control for baseline characteristics.

RESULTS

28 subjects (22%) were on statins and 99 subjects (78%) were not. Mean cIMT at baseline was 1.2 mm (SD = 0.34) in statin users and 1.1 mm (SD = 0.34) in non-users, and the multivariable adjusted difference was 0.05mm (95%CI -0.11, 0.21 p = 0.53). After 3.2 years of follow-up, average cIMT progression was similar in statin users and non-users (0.062mm/yr vs. 0.058 mm/yr) and the multivariable adjusted difference over the study period was 0.004 mm/yr (95% CI -0.018, 0.025, p = 0.74). All-cause mortality appeared higher in non-statin users compared with statin users, but the difference was not significant (adjusted HR = 0.74, 95%CI 0.17-3.29, p = 0.70).

CONCLUSION

In a HIV cohort who had elevated ASCVD risk and meet ACC/AHA criteria for statins, treatment with statins was not associated with a reduction in carotid atherosclerosis progression or total mortality. Future studies are needed to further explore the impact of statins on cardiovascular risk in the HIV-infected population.

Current pharmacotherapy for the treatment of dyslipidemia associated with HIV infection

Introduction: Cardiovascular disease is an important cause of morbidity and mortality in persons with human immunodeficiency virus (PWH). The risk of atherosclerotic cardiovascular disease (ASCVD) is higher in PWH compared to uninfected persons. Dyslipidemia is a critical link in the pathogenesis of ASCVD in PWH. Chronic inflammation associated with HIV infection may drive both dyslipidemia and ASCVD. Areas covered: The authors review the evidence for using lipid-lowering therapy in PWH and includes an overview of the utility and complexity of using statins in PWH, in particular, drug interactions, safety, and efficacy. In addition, data covering alternate therapies like omega-3 fatty acids, fibrates, niacin, ezetimibe, and PCSK-9 inhibitors are reviewed. Expert opinion: Dyslipidemia is a common problem in PWH. The risk of ASCVD is higher in PWH. Lipid-lowering therapy reduces the risk of ASCVD, but clinical endpoint trials are lacking in PWH. Statin therapy is the mainstay of primary prevention for ASCVD. The timing of when to initiate primary prevention with statins in PWH is unclear. Beyond statins, there are limited data that other lipid-lowering agents have utility in PWH. Ongoing trials like the REPRIEVE trial will inform the community about the optimal approach to lipid-lowering therapy in PWH.

Brachial Artery Echogenicity and Grayscale Texture Changes in HIV-Infected Individuals Receiving Low-Dose Methotrexate

Objective- We evaluated the biological effects of low-dose methotrexate on 3 novel brachial artery grayscale ultrasound measures that may indicate subclinical arterial injury. Approach and Results- Exploratory analysis from a clinical trial of people with HIV infection at increased cardiovascular disease risk who were randomly assigned to low-dose methotrexate (target dose 15 mg/wk) or placebo. Brachial artery ultrasound grayscale median, gray level difference statistic texture-contrast (GLDS-CON), and gray level texture entropy were measured at baseline and after 24 weeks of intervention. Findings from the intention-to-treat (N=148) and adequately-dosed (N=118) populations were consistent, so the adequately-dosed population results are presented. Participants were a median (Q1, Q3) age of 54 (50, 60) years. After 24 weeks, the low-dose methotrexate intervention was associated with a 25.4% (-18.1, 58.6; P=0.007) increase in GLDS-CON compared with 1.3% (-29.1, 44.7; P=0.97) with placebo ( P=0.05) and a 0.10 u (-0.06, 0.23; P=0.026) increase in entropy compared with 0.02 u (-0.11, 0.14; P=0.54) with placebo ( P=0.14). At week 24, changes in CD4+ T cells correlated inversely with changes in GLDS-CON (ρ=-0.20; P=0.031), and entropy (ρ=-0.21; P=0.023). Changes in D-dimer levels, but no other inflammatory biomarkers, also correlated inversely with changes in GLDS-CON (ρ=-0.23; P=0.014) and entropy (ρ=-0.26; P=0.005). Conclusions- Brachial artery GLDS-CON and entropy increased after 24 weeks of low-dose methotrexate, though the latter was not significantly different from placebo. Grayscale changes were associated with decreases in CD4+ T-cell and D-dimer concentrations and may indicate favorable arterial structure changes.

Low-density lipoprotein cholesterol response after statin initiation among persons living with human immunodeficiency virus

BACKGROUND

Meta-analyses of general population studies report mean low-density lipoprotein cholesterol (LDL-C) reductions of 30% to <50% with moderate-intensity and ≥50% with high-intensity statins. Persons living with human immunodeficiency virus (PLWH) are at high risk for atherosclerotic cardiovascular disease (ASCVD), yet many have elevated LDL-C.

OBJECTIVE

To evaluate LDL-C response after statin initiation among PLWH.

METHODS

We conducted a retrospective cohort study of PLWH initiating statins between 2009 and 2013 (N = 706). Patients were categorized into mutually exclusive groups in the following hierarchy: history of coronary heart disease (CHD), diabetes, prestatin LDL-C ≥190 mg/dL, 10-year predicted ASCVD risk ≥7.5%, and none of the above (ie, unknown statin indication). The primary outcome was a ≥30% reduction in LDL-C after statin initiation.

RESULTS

Among patients initiating statins, 5.8% had a history of CHD, 13.6% had diabetes, 6.2% had LDL-C ≥190 mg/dL, 35.4% had 10-year ASCVD risk ≥7.5%, and 39.0% had an unknown statin indication. Among patients with a history of CHD, 31.7% achieved a ≥30% LDL-C reduction compared with 25.0%, 59.1%, and 33.9% among those with diabetes, LDL-C ≥190 mg/dL, and 10-year ASCVD risk ≥7.5%, respectively. In multivariable adjusted analyses and compared to patients with an unknown statin indication, LDL-C ≥ 190 mg/dL was associated with a prevalence ratio for an LDL-C reduction ≥30% of 1.81 (95% confidence interval, 1.34-2.45), whereas no statistically significant association was present for history of CHD, diabetes, and 10-year ASCVD risk ≥7.5%.

CONCLUSION

A low percentage of PLWH achieved the expected reductions in LDL-C after statin initiation, highlighting an unmet need for ASCVD risk reduction.

Association of Human Immunodeficiency Virus Infection and Risk of Peripheral Artery Disease

BACKGROUND

The effect of human immunodeficiency virus (HIV) on the development of peripheral artery disease (PAD) remains unclear. We investigated whether HIV infection is associated with an increased risk of PAD after adjustment for traditional atherosclerotic risk factors in a large cohort of HIV-infected (HIV+) and demographically similar HIV-uninfected veterans.

METHODS

We studied participants in the Veterans Aging Cohort Study from April 1, 2003 through December 31, 2014. We excluded participants with known prior PAD or prevalent cardiovascular disease (myocardial infarction, stroke, coronary heart disease, and congestive heart failure) and analyzed the effect of HIV status on the risk of incident PAD events after adjusting for demographics, PAD risk factors, substance use, CD4 cell count, HIV-1 ribonucleic acid, and antiretroviral therapy. The primary outcome is incident peripheral artery disease events. Secondary outcomes include mortality and amputation in subjects with incident PAD events by HIV infection status, viral load, and CD4 count.

RESULTS

Among 91 953 participants, over a median follow up of 9.0 years, there were 7708 incident PAD events. Rates of incident PAD events per 1000 person-years were higher among HIV+ (11.9; 95% confidence interval [CI], 11.5-12.4) than uninfected veterans (9.9; 95% CI, 9.6-10.1). After adjustment for demographics, PAD risk factors, and other covariates, HIV+ veterans had an increased risk of incident PAD events compared with uninfected veterans (hazard ratio [HR], 1.19; 95% CI, 1.13-1.25). This risk was highest among those with time-updated HIV viral load >500 copies/mL (HR, 1.51; 95% CI, 1.38-1.65) and CD4 cell counts <200 cells/mm³ (HR, 1.91; 95% CI, 1.71-2.13). In contrast, HIV+ veterans with time updated CD4 cell count ≥500 cells/mm³ had no increased risk of PAD (HR, 1.03; 95% CI, 0.96-1.11). Mortality rates after incident PAD events are high regardless of HIV status. HIV infection did not affect rates of amputation after incident PAD events.

CONCLUSIONS

Infection with HIV is associated with a 19% increased risk of PAD beyond that explained by traditional atherosclerotic risk factors. However, for those with sustained CD4 cell counts <200 cells/mm³, the risk of incident PAD events is nearly 2-fold higher whereas for those with sustained CD4 cell counts ≥500 cells/mm³ there is no excess risk of incident PAD events compared with uninfected people.

Human Immunodeficiency Virus Infection, Antiretroviral Therapy, and Statin: a Clinical Update

PURPOSE OF REVIEW

This clinical update is intended to focus in relationship between HIV infection and use of antiretroviral therapy (ART) and statin.

RECENT FINDINGS

Though ART significantly changed the course of HIV infection, it is related to numerous side effects principally to the lipid profile. In this way, statins became one of the most used lipid-lowering therapies in this population. In our clinical update, we evaluated studies that demonstrate the relationship and molecular mechanisms that HIV infection and ART use trigger dyslipidemia and also the use of statin to reduce this condition. We have demonstrated that use of statin can be used in dyslipidemic HIV-infected people as long as there is no drug interaction with ART. Recently, studies using rosuvastatin have shown greater effects when compared to the other statins.

Conflicting effects of atazanavir therapy on atherosclerotic risk factors in stable HIV patients: A randomized trial of regimen switch to atazanavir

Bilirubin acts as a potent endogenous antioxidant, with higher concentrations associated with lower rates of CVD; the antiretroviral drug atazanavir (ATV) increases bilirubin levels but may also increase von Willebrand factor levels. We tested the hypothesis that increasing endogenous bilirubin using ATV would improve cardiometabolic risk factors and vascular function in older patients with HIV. Ninety participants were enrolled in two study protocols. In protocol 1, we evaluated markers of inflammation, thrombosis, and conduit artery endothelial function in subjects on non-ATV containing regimens. Participants were randomly assigned to continue baseline treatment or switch to an ATV-based regimen. Measurements were made at baseline and 28 days. In the protocol 2, we enrolled 30 subjects who received atazanavir for more than one year and were compared to the aim 1 protocol subjects at baseline. 60 subjects were enrolled in the first protocol (mean age 53, +/- 6 years), with 31 randomized to ATV and 29 continuing baseline treatment. Atazanavir significantly increased serum total bilirubin levels (p<0.001) and acutely but not chronically plasma total antioxidant capacity (p<0.001). An increase in von Willebrand Factor (p<0.001) and reduction in hs-CRP (p = 0.034) were noted. No changes were seen in either flow-mediated endothelium-dependent or vasodilation. In cross-sectional analysis (second protocol), similar findings were seen in the baseline attributes of non-atazanavir-based and long-term atazanavir users. Increasing serum bilirubin levels with atazanavir in subjects with HIV reduces hs-CRP, temporarily reduces oxidative stress, but increases von Willebrand Factor. Atazanavir does not improve endothelial function of conduit arteries.

Trial registration: ClinicalTrials.gov NCT03019783.

Evidence-based review of statin use in patients with HIV on antiretroviral therapy

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Cardiovascular disease is up to two times more prevalent in patient with HIV.

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Based on pharmacokinetic and clinical data, atorvastatin and pravastatin are generally considered safe for HIV patients receiving ART.

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Rosuavstatin is generally safe if started at a low dose and a maximum 20 mg per day.

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Fluvastatin, lovastatin, and simvastatin should be avoided in patients with HIV receiving ART.

Introduction

As a result of improved safe and effective therapeutic options for human immunodeficiency virus (HIV), life expectancy of those living with HIV is increasing leading to new challenges (e.g., management of chronic diseases). Some chronic diseases (e.g., cardiovascular disease [CVD]), are up to two times more prevalent in patients with HIV. Statins are a mainstay of therapy for prevention of CVD; but, clinicians should be aware that not all statins are appropriate for use in the HIV population, especially those receiving antiretroviral therapy (ART). The purpose of this article is to review the pharmacokinetic and clinical data for statin therapy in HIV-infected patients receiving ART.

Methods

A systematic literature search using PubMed and MEDLINE databases was performed using each statin drug name combined with HIV, pharmacokinetics, AIDS, and/or human immunodeficiency virus. English language trials published from 1946 to November 2016 were considered, and results were limited to clinical efficacy trials.

Results

In general, atorvastatin and pravastatin are safe and effective for patients treated with protease-inhibitor (PI) or non-nucleoside reverse transcriptase inhibitor-based ART. Rosuvastatin is generally considered safe if started at a low dose, but should be avoided if possible in patients receiving PI-based ART. Pitavastatin has limited supporting evidence, but appears safe for use based on its pharmacokinetic properties and low number of drug interactions. Fluvastatin, lovastatin, and simvastatin should be avoided in patients receiving ART due to drug interactions, adverse events, and/or limited clinical data.

Conclusion

Clinicians need to be familiar with the intricacies of statin selection for the prevention of CVD in patients with HIV on ART.

Statins to improve cardiovascular outcomes in treated HIV infection

PURPOSE OF REVIEW

To evaluate evidence that statins reduce cardiovascular risk in patients living with HIV.

RECENT FINDINGS

Moderate to high-dose atorvastatin and rosuvastatin appear to reduce noncalcified coronary plaque volume and slow progression of carotid intima-media thickness in patients with treated HIV infection. Expected lipoprotein changes with statins on the background of modern antiretroviral therapy are similar to the general population. In addition to lipids, the statin benefit may be mediated in part by improvements in vascular inflammation and levels of T-cell and monocyte activation. One concern is the potential for rosuvastatin to cause insulin resistance. Decisions to prescribe statins must be done in the context of global risk assessment, but traditional risk calculators such as the Framingham Risk Score or the American College of Cardiology/American Heart Association pooled-risk equations underestimate risk in this population. Furthermore, many patients with subclinical disease would not be recommended for statins according to the most recent American College of Cardiology/American Heart Association guidelines.

SUMMARY

Statins are likely to improve cardiovascular outcomes for patients with HIV, but results of the first outcome study are not expected until 2020. In the meantime, clinicians should individualize statin prescriptions, and should consider using more potent statins (rosuvastatin, atorvastatin, and pitavastatin) when possible.

Pathophysiology and management of cardiovascular disease in patients with HIV

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

A PRISMA-compliant systematic review and meta-analysis of randomized controlled trials investigating the effects of statin therapy on plasma lipid concentrations in HIV-infected patients

Statin therapy may lower plasma lipid concentrations, but the evidence in HIV-infected patients is still unclear. Therefore, we aimed to investigate the impact of statin therapy on plasma lipid concentrations through a systematic review of the literature and meta-analysis of available randomized controlled trials (RCTs). The literature search included PUBMED, SCOPUS, Web of Science and Google Scholar up to October 30, 2015. The meta-analysis was performed using either a fixed-effects or random-effect model according to I(2) statistic. Effect sizes were expressed as weighted mean difference (WMD) and 95% confidence interval (CI). Two investigators independently reviewed the title or abstract, further reviewed the full-texts and extracted information on study characteristics and study outcomes. Meta-analysis of 12 RCTs with 697 participants suggested significant reductions in plasma concentrations of low density lipoprotein (LDL) cholesterol (WMD: -0.72mmol/L [-27.8mg/dL], 95%CI: -1.04, -0.39, p<0.001; I(2)=85.7%), total cholesterol (WMD: -1.03mmol/L [-39.8mg/dL], 95%CI: -1.42, -0.64, p<0.001; I(2)=94.7%) and non-high density lipoprotein cholesterol (non-HDL-C) (WMD: -0.81mmol/L [-31.3mg/dl], 95%CI: -1.32, -0.30, p=0.002; I(2)=76.5%), and elevations in HDL-C (WMD: 0.072mmol/L [2.8mg/dL], 95%CI: 0.053, 0.092, p<0.001; I(2)=0%) following treatment with statins (mostly of moderate-intensity). No significant alteration in plasma triglycerides (TG) concentrations was found (WMD: -0.16mmol/L [-14.2mg/dL], 95%CI: -0.61, 0.29, p=0.475; I(2)=90.2%). All these effects were robust in sensitivity analysis, suggesting that the computed effect is not driven by any single study. In subgroup analysis, no significant difference was found among different statins in terms of changing plasma concentrations of LDL-C, HDL-C and TG. However, atorvastatin was found to be more efficacious in reducing plasma total cholesterol concentrations (p<0.001). In conclusion, the meta-analysis suggested significant reductions in plasma concentrations of LDL-C, total cholesterol and non-HDL-C, and elevations in HDL-C, but no significant alteration in plasma TG following treatment with statins.

The role of statins in the setting of HIV infection

HIV-infected individuals are at an increased risk of cardiovascular disease (CVD) and other HIV-related co-morbidities. This is due in part to dyslipidemia associated with antiretroviral therapy and increased inflammation and immune activation from chronic HIV infection. Statins not only have potent lipid-lowering properties but are also anti-inflammatory and immunomodulators. Studies suggest that statin therapy in the HIV-infected population may decrease the risk of CVD and other non-AIDS-defining co-morbidities. This review summarizes the recent literature on statin use in the HIV setting.

Comparative safety and efficacy of statins for primary prevention in human immunodeficiency virus-positive patients: a systematic review and meta-analysis

The efficacy and safety of different statins for human immunodeficiency virus (HIV)-positive patients in the primary prevention setting remain to be established. In the present meta-analysis, 18 studies with 736 HIV-positive patients receiving combination antiretroviral therapy (cART) and treated with statins in the primary prevention setting were included (21.0% women, median age 44.1 years old). The primary endpoint was the effect of statin therapy on total cholesterol (TC) levels. Rosuvastatin 10 mg and atorvastatin 10 mg provided the largest reduction in TC levels [mean -1.67, 95% confidence interval (CI) (-1.99, -1.35) mmol/L; and mean -1.44, 95% CI (-1.85, -1.02) mmol/L, respectively]. Atorvastatin 80 mg and simvastatin 20 mg provided the largest reduction in low-density lipoprotein (LDL) [mean -2.10, 95% CI (-3.39, -0.81) mmol/L; and mean -1.57, 95% CI (-2.67, -0.47) mmol/L, respectively]. Pravastatin 10-20 mg [mean 0.24, 95% CI (0.10, 0.38) mmol/L] and atorvastatin 10 mg [mean 0.15, 95% CI (0.007, 0.23) mmol/L] had the largest increase in high-density lipoprotein, whereas atorvastatin 80 mg [mean -0.60, 95% CI (-1.09, -0.11) mmol/L] and simvastatin 20 mg [mean -0.61, 95% CI (-1.14, -0.08) mmol/L] had the largest reduction in triglycerides. The mean discontinuation rate was 0.12 per 100 person-years [95% CI (0.05, 0.20)], and was higher with atorvastatin 10 mg [26.5 per 100 person-years, 95% CI (-13.4, 64.7)]. Meta-regression revealed that nucleoside reverse transcriptase inhibitors-sparing regimens were associated with reduced efficacy for statin's ability to lower TC. Statin therapy significantly lowers plasma TC and LDL levels in HIV-positive patients and is associated with low rates of adverse events. Statins are effective and safe when dose-adjusted for drug-drug interactions with cART.

Effects of pravastatin, phytosterols, and combination therapy on lipid profile in HIV-infected patients: an open-labelled, randomized cross-over study

BACKGROUND

To determine the effects of 40 mg of pravastatin, 2 g of phytosterols, and combination therapy on lipid profiles and to compare the reduction of LDL cholesterol between combination therapy and monotherapy.

METHODS

Thirty-six HIV-infected patients treated with ARVs who had high LDL cholesterol levels but no current usage of any lipid-lowering agents were enrolled into the open-labelled, randomized, cross-over study. All patients were assigned randomly into one of four intervention groups: (1) pravastatin 40 mg cross-over to the combination of pravastatin 40 mg and phytosterols 2 g (combination group), (2) the combination group cross-over to pravastatin 40 mg, (3) phytosterols 2 g cross-over to the combination group, and (4) the combination group cross-over to phytosterols 2 g. Each active treatment lasted 4 weeks with a wash-out period of 4 weeks.

RESULTS

The baseline mean TC, TG, HDL-c, and LDL-c levels in 36 HIV patients were 248.09 ± 34.73, 172.36 ± 125.44, 54.92 ± 16.67, and 175.13 ± 29.00 mg/dl, respectively. Pravastatin, phytosterols, and combination therapy reduced TC and LDL-c but TG and HDL-c were not significantly different from the baselines. The mean LDL-c reductions in the pravastatin, phytosterols, and the combination groups were 28.76 ± 9.32, 9.12 ± 7.84, and 27.08 ± 15.58%, respectively. The LDL-c levels in the pravastatin and combination groups were reduced more than in the phytosterols group (p < 0.01). There was no difference in the LDL-c reduction between the combination and pravastatin monotherapy groups (-25.61 ± 10.43 vs. -28.12 ± 14.07%, p = 0.555).

CONCLUSION

Pravastatin had moderate potency on LDL-c lowering in HIV patients but could not bring LDL-c to goal. Adding phytosterols to pravastatin for a 4-week duration could not demonstrate any additional lipid-lowering effect

TRIAL REGISTRATION

Thai Clinical Trial Registry: TCTR20150126002 date: January 23, 2015.

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.

Effects of statin therapy on coronary artery plaque volume and high-risk plaque morphology in HIV-infected patients with subclinical atherosclerosis: a randomised, double-blind, placebo-controlled trial

BACKGROUND

HIV-infected patients have a high risk of myocardial infarction. We aimed to assess the ability of statin treatment to reduce arterial inflammation and achieve regression of coronary atherosclerosis in this population.

METHODS

In a randomised, double-blind, placebo-controlled trial, 40 HIV-infected participants with subclinical coronary atherosclerosis, evidence of arterial inflammation in the aorta by fluorodeoxyglucose (FDG)-PET, and LDL-cholesterol concentration of less than 3.37 mmol/L (130 mg/dL) were randomly assigned (1:1) to 1 year of treatment with atorvastatin or placebo. Randomisation was by the Massachusetts General Hospital (MGH) Clinical Research Pharmacy with a permuted-block algorithm, stratified by sex with a fixed block size of four. Study codes were available only to the MGH Research Pharmacy and not to study investigators or participants. The prespecified primary endpoint was arterial inflammation as assessed by FDG-PET of the aorta. Additional prespecified endpoints were non-calcified and calcified plaque measures and high risk plaque features assessed with coronary CT angiography and biochemical measures. Analysis was done by intention to treat with all available data and without imputation for missing data. The trial is registered with ClinicalTrials.gov, number NCT00965185.

FINDINGS

The study was done from Nov 13, 2009, to Jan 13, 2014. 19 patients were assigned to atorvastatin and 21 to placebo. 37 (93%) of 40 participants completed the study, with equivalent discontinuation rates in both groups. Baseline characteristics were similar between groups. After 12 months, change in FDG-PET uptake of the most diseased segment of the aorta was not different between atorvastatin and placebo, but technically adequate results comparing longitudinal changes in identical regions could be assessed in only 21 patients (atorvastatin Δ -0.03, 95% CI -0.17 to 0.12, vs placebo Δ -0.06, -0.25 to 0.13; p=0.77). Change in plaque could be assessed in all 37 people completing the study. Atorvastatin reduced non-calcified coronary plaque volume relative to placebo: median change -19.4% (IQR -39.2 to 9.3) versus 20.4% (-7.1 to 94.4; p=0.009, n=37). The number of high-risk plaques was significantly reduced in the atorvastatin group compared with the placebo group: change in number of low attenuation plaques -0.2 (95% CI -0.6 to 0.2) versus 0.4 (0.0, 0.7; p=0.03; n=37); and change in number of positively remodelled plaques -0.2 (-0.4 to 0.1) versus 0.4 (-0.1 to 0.8; p=0.04; n=37). Direct LDL-cholesterol (-1.00 mmol/L, 95% CI -1.38 to 0.61 vs 0.30 mmol/L, 0.04 to 0.55, p<0.0001) and lipoprotein-associated phospholipase A2 (-52.2 ng/mL, 95% CI -70.4 to -34.0, vs -13.3 ng/mL, -32.8 to 6.2; p=0.005; n=37) decreased significantly with atorvastatin relative to placebo. Statin therapy was well tolerated, with a low incidence of clinical adverse events.

INTERPRETATION

No significant effects of statin therapy on arterial inflammation of the aorta were seen as measured by FDG-PET. However, statin therapy reduced non-calcified plaque volume and high-risk coronary plaque features in HIV-infected patients. Further studies should assess whether reduction in high-risk coronary artery disease translates into effective prevention of cardiovascular events in this at-risk population.

FUNDING

National Institutes of Health, Harvard Clinical and Translational Science Center, National Center for Research Resources.

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.

High-fat meals do not impair postprandial endothelial function in HIV-infected and uninfected men

Prior studies have demonstrated impaired endothelium-dependent flow-mediated dilation (FMD) in healthy subjects following a high-fat meal. Compared to uninfected individuals, HIV-infected persons have been shown to have impaired FMD. We examined the effect of two different high-fat meals on endothelial function in HIV-infected and uninfected men. We performed a randomized, parallel group crossover study comparing 47 white men [18 HIV-uninfected, 9 HIV-infected and antiretroviral therapy (ART)-naïve, and 20 HIV-infected men on ART]. Fasting participants consumed one of two randomly assigned high-fat meals of either saturated or polyunsaturated fat, followed at least 24 h later by the other meal. Brachial artery ultrasound measurements to assess vascular reactivity were performed before and 3 h after each dietary challenge. There was no significant difference in mean baseline or postprandial FMD between HIV-infected and HIV-uninfected participants (mean baseline FMD±SD, 9.0%±5 vs. 9.2%±5, p=0.9; mean postprandial FMD±SD, 9.0%±4.7 vs. 9.1%±4.7, p=0.96, respectively). No significant difference in baseline or postprandial change in FMD was found between meals or HIV treatment groups. Fasting lipids and glucose, CD4(+) count, and viral load did not predict FMD in HIV-infected participants. In contrast to previous reports, this study did not demonstrate impaired endothelium-dependent vasodilation after high-fat meals in either HIV-infected or HIV-uninfected men. Moreover, HIV infection itself may not be the primary explanation for the abnormal endothelial function reported in HIV-infected individuals.

Arterial disease in patients with human immunodeficiency virus infection: what has imaging taught us?

With advances in antiretroviral therapy (ART), individuals with human immunodeficiency virus (HIV) infection are living longer and increasingly die of non-HIV-related diseases, such as cardiovascular disease (CVD). Several observational studies suggest that HIV-infected patients on ART are at increased risk of CVD; however, the precise mechanisms underlying the association between HIV infection and CVD risk are uncertain. Atherosclerosis and arterial disease in HIV-infected individuals is a multifactorial process with several potential targets for research and therapeutic intervention. This paper critically reviews the contributions of imaging to our understanding of arterial disease, atherosclerosis, and CVD risk in HIV-infected individuals. In general, the findings of studies using carotid ultrasound, coronary computed tomographic angiography, and aortic positron emission tomography agree with those from observational studies of CVD events and suggest that HIV infection is associated with an increased risk of CVD. Observational studies of CVD outcomes and studies using carotid intima-media thickness suggest that there is a moderate increase in CVD risk related to HIV serostatus. Less can be said about the role of ART and specific ART therapies in CVD risk, mainly because imaging studies have had serious methodological limitations that diminish their generalizability. Brachial artery reactivity testing has been especially useful for elucidating the arterial pathophysiology of HIV infection and its treatments, as well as the arterial effects of interventions for treating HIV and dyslipidemia. Aortic positron emission tomography has been especially useful for evaluating arterial inflammation. Coronary artery calcium has not proven to be a useful marker of subclinical atherosclerosis in HIV-infected individuals. Imaging studies support the intriguing hypothesis that persistent inflammation and immune dysregulation contribute to increased CVD risk among treated and suppressed patients with HIV infection.

Systematic review: Evaluating the effect of lipid-lowering therapy on lipoprotein and lipid values

PURPOSE

This systematic review was performed to summarize published experience using low density lipoprotein particle number (LDL-P) to monitor the efficacy of lipid-lowering pharmacotherapies.

METHODS

Studies were identified from a literature search of MEDLINE (January 1, 2000 - June 30, 2012); and abstract searches of select conferences. All accepted studies reported mean (or median) nuclear magnetic resonance (NMR)-based LDL-P values for at least 10 subjects receiving lipid lowering pharmacotherapy.

RESULTS

Searches revealed 36 studies (with 61 treatment arms) in which LDL-P measurements were reported pre- and post-treatment. Most studies also reported changes in low-density lipoprotein cholesterol (LDL-C), but fewer studies reported changes in apolipoprotein B (apoB)(n = 20) and non-HDL-C (n = 28). Treatments included statins (22 arms/15 studies), fibrates (7 arms/7 studies), niacin (7 arms/6 studies), bile acid sequestrants (5 arms/2 studies), an anti-apoB oligonucleotide (2 arms/2 studies), combination therapies (8 arms/6 studies), anti-diabetics (5 arms/4 studies), and, other treatments (5 arms/2 studies). Lipid-lowering pharmacotherapy resulted in reductions in mean LDL-P in all but two studies. In several statin studies, the percent reductions in LDL-P were smaller than reductions in LDL-C, comparable changes were reported when LDL-P and apoB, were reported.

CONCLUSIONS

Study-level data from this systemic review establish that different lipid lowering agents can lead to discordance between LDL-P and LDL-C, therefore, basing LDL-lowering therapy only on the achievement of cholesterol goals may result in a treatment gap. Therefore, the use of LDL-P for monitoring lipid-lowering therapy, particularly for statins, can provide a more accurate assessment of residual cardiovascular risk.

Vitamin D levels and markers of arterial dysfunction in HIV

HIV-infected patients have low vitamin D levels as well as an increase in cardiovascular (CVD) risk. We examined the relationship between vitamin D and three markers of arterial dysfunction among HIV-infected individuals on stable antiretroviral (ARV) therapy. Levels of 25-hydroxyvitamin D [25(OH)D] were assessed by chemiluminescent immunoassay (DiaSorin) in 100 enrollees into the Hawaii Aging with HIV-Cardiovascular Cohort Study, a cohort of HIV-infected subjects age ≥ 40 years on stable (≥ 6 months) ARV therapy. The relationships between 25(OH)D levels and brachial artery flow-mediated dilation (FMD), right common carotid artery intima-media thickness (cIMT), and coronary artery calcium (CAC) were examined. Analytical methods included Pearson's correlations, Kruskal-Wallis tests, relative risks, and linear regression models. The cohort was 86% male and 60% white with a median age of 52 years and CD4 of 510 cells/mm(3). The median (Q1, Q3) level of 25(OH)D was 27.9 ng/ml (21.8, 38.3). There were 72 FMD, 50 cIMT, and 90 CAC measurements available for analyses. A significant correlation was observed between 25(OH)D levels and FMD (r=0.30, p=0.01) but not with cIMT (r=-0.05, p=0.76). In a linear regression model, Framingham risk score attenuated the relationship between FMD and 25(OH)D. Those with lower 25(OH)D levels were at slightly higher risk of having CAC (RR=1.02, p=0.04). Among those with CAC, lower 25(OH)D levels were not associated with higher CAC scores (p=0.36). Lower vitamin D levels are associated with evidence of subclinical arterial dysfunction in HIV-infected individuals. The significance of these findings warrants further investigation.

Heart rate variability and non-linear dynamics in risk stratification

The time-domain measures and power–spectral analysis of heart rate variability (HRV) are classic conventional methods to assess the complex regulatory system between autonomic nervous system and heart rate and are most widely used. There are abundant scientific data about the prognostic significance of the conventional measurements of HRV in patients with various conditions, particularly with myocardial infarction. Some studies have suggested that some newer measures describing non-linear dynamics of heart rate, such as fractal measures, may reveal prognostic information beyond that obtained by the conventional measures of HRV. An ideal risk indicator could specifically predict sudden arrhythmic death as the implantable cardioverter-defibrillator (ICD) therapy can prevent such events. There are numerically more sudden deaths among post-infarction patients with better preserved left ventricular function than in those with severe left ventricular dysfunction. Recent data support the concept that HRV measurements, when analyzed several weeks after acute myocardial infarction, predict life-threatening ventricular tachyarrhythmias in patients with moderately depressed left ventricular function. However, well-designed prospective randomized studies are needed to evaluate whether the ICD therapy based on the assessment of HRV alone or with other risk indicators improves the patients’ prognosis. Several issues, such as the optimal target population, optimal timing of HRV measurements, optimal methods of HRV analysis, and optimal cutpoints for different HRV parameters, need clarification before the HRV analysis can be a widespread clinical tool in risk stratification.

Hypertriglyceridemia, Metabolic Syndrome, and Cardiovascular Disease in HIV-Infected Patients: Effects of Antiretroviral Therapy and Adipose Tissue Distribution

The use of combination antiretroviral therapy (CART) in HIV-infected patients has resulted in a dramatic decline in AIDS-related mortality. However, mortality due to non-AIDS conditions, particularly cardiovascular disease (CVD) seems to increase in this population. CART has been associated with several metabolic risk factors, including insulin resistance, low HDL-cholesterol, hypertriglyceridemia and postprandial hyperlipidemia. In addition, HIV itself, as well as specific antiretroviral agents, may further increase cardiovascular risk by interfering with endothelial function. As the HIV population is aging, CVD may become an increasingly growing health problem in the future. Therefore, early diagnosis and treatment of cardiovascular risk factors is warranted in this population. This paper reviews the contribution of both, HIV infection and CART, to insulin resistance, postprandial hyperlipidemia and cardiovascular risk in HIV-infected patients. Strategies to reduce cardiovascular risk are also discussed.

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.

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.

Heart rate variability and non-linear dynamics in risk stratification

The time-domain measures and power-spectral analysis of heart rate variability (HRV) are classic conventional methods to assess the complex regulatory system between autonomic nervous system and heart rate and are most widely used. There are abundant scientific data about the prognostic significance of the conventional measurements of HRV in patients with various conditions, particularly with myocardial infarction. Some studies have suggested that some newer measures describing non-linear dynamics of heart rate, such as fractal measures, may reveal prognostic information beyond that obtained by the conventional measures of HRV. An ideal risk indicator could specifically predict sudden arrhythmic death as the implantable cardioverter-defibrillator (ICD) therapy can prevent such events. There are numerically more sudden deaths among post-infarction patients with better preserved left ventricular function than in those with severe left ventricular dysfunction. Recent data support the concept that HRV measurements, when analyzed several weeks after acute myocardial infarction, predict life-threatening ventricular tachyarrhythmias in patients with moderately depressed left ventricular function. However, well-designed prospective randomized studies are needed to evaluate whether the ICD therapy based on the assessment of HRV alone or with other risk indicators improves the patients' prognosis. Several issues, such as the optimal target population, optimal timing of HRV measurements, optimal methods of HRV analysis, and optimal cutpoints for different HRV parameters, need clarification before the HRV analysis can be a widespread clinical tool in risk stratification.

Short-term effects of extended-release niacin on endothelial function in HIV-infected patients on stable antiretroviral therapy

OBJECTIVE

To assess the short-term effects of extended-release niacin (ERN) on endothelial function in HIV-infected patients with low high-density lipoprotein-cholesterol (HDL-c) levels.

METHODS

Randomized controlled study to determine the short-term effects of ERN on endothelial function, measured by flow-mediated vasodilation (FMD) of the brachial artery, in HIV-infected adults with low HDL-c. Participants on stable HAART with fasting HDL-c less than 40 mg/dl and low-density lipoprotein-cholesterol less than 130 mg/dl were randomized to ERN or control arms. ERN treatment started at 500 mg/night and titrated to 1500 mg/night for 12 weeks. Controls received the same follow-up but were not given ERN (no placebo). Participants were excluded if they had a history of cardiac disease, uncontrolled hypertension, diabetes mellitus, or were on lipid-lowering medications such as statins and fibrates. Change in FMD was compared between arms with respect to baseline HDL-c.

RESULTS

Nineteen participants were enrolled: 89% men, median age 50 years, 53% white/non-Hispanic, median CD4 cell count 493 cells/microl, and 95% of them had HIV RNA below 50 copies/ml. Participants receiving ERN had a median HDL-c (interquartile range) increase of 3.0 mg/dl (0.75 to 5.0) compared with -1.0 mg/dl in controls (-6.0 to 2.5), a P value is equal to 0.04. The median change in FMD was 0.91% (-2.95 to 2.21) for ERN and -0.48% (-2.65 to 0.98) for controls (P = 0.67). However, end of study FMD for ERN was significantly different from controls after adjusting for baseline differences in FMD and HDL-c, 6.36% (95% confidence interval 4.85-7.87) and 2.73% (95% confidence interval 0.95-4.51) respectively, a P value is equal to 0.048.

CONCLUSION

This pilot study demonstrated that short-term niacin therapy could improve endothelial function in HIV-infected patients with low HDL-c.

Change to atazanavir/ritonavir treatment improves lipids but not endothelial function in patients on stable antiretroviral therapy

OBJECTIVE

Protease inhibitors and other antiretroviral drugs have been associated with dyslipidemia, endothelial dysfunction, and increased cardiovascular disease risk. The protease inhibitor atazanavir has an advantageous lipid profile; we studied its effects on arterial function and other metabolic and inflammatory cardiovascular disease risk factors.

DESIGN

Prospective, randomized, multinational trial in HIV-infected patients receiving stable protease inhibitor-based therapy with plasma HIV RNA less than 500 copies/ml and fasting low-density lipoprotein cholesterol more than 130 mg/dl, or triglycerides more than 200 mg/dl.

METHODS

Patients were randomized to continue their current protease inhibitor or switch the protease inhibitor to atazanavir and continue ritonavir if given as a protease inhibitor booster for 24 weeks. Brachial artery flow-mediated dilation, lipoproteins, and inflammatory and metabolic markers were measured at baseline, week 12, and week 24. Median changes within (signed rank test) and between (Wilcoxon test) arms were calculated.

RESULTS

Twenty-six patients switched to atazanavir (all continued on ritonavir); 24 remained on their protease inhibitor regimen. Median CD4 cell count was 499 cells/mul, total cholesterol 204 mg/dl, low-density lipoprotein cholesterol 122 mg/dl, and triglycerides 244 mg/dl. There were no significant changes in flow-mediated dilation after 12 and 24 weeks. At 24 weeks, significant changes in the atazanavir vs. continued protease inhibitor group were observed for total cholesterol (-25 vs. +1.5 mg/dl, P = 0.009), triglycerides (-58 vs. +3.5 mg/dl, P = 0.013), and nonhigh-density lipoprotein cholesterol (-27 vs. -0.5 mg/dl, P = 0.014).

CONCLUSION

In dyslipidemic individuals with suppressed HIV RNA on stable therapy, changing the protease inhibitor to atazanavir/ritonavir for 24 weeks improved lipids; however, endothelial function, inflammatory, and metabolic markers did not change.

Antiretroviral therapy with heart

Antiretroviral therapy (ART) has resulted in a substantial improvement in the morbidity and mortality associated with human immunodeficiency virus (HIV) infection. As this population ages, cardiovascular disease is becoming an increasingly important health burden. It is clear that many factors are involved in the development of this problem, with traditional risk factors (smoking, dyslipidemia, diabetes, family history, hypertension) the main contributors. ART and HIV infection itself can modify the risk of cardiovascular disease. Not only does this increased risk seem to be mediated through effects on traditional cardiovascular risk factors, namely dyslipidemia and insulin resistance, but there is also some evidence that HIV and ART may be associated with accelerated atherosclerosis and endothelial dysfunction. Current data are conflicting and further investigation into this area is needed. Drugs from both nucleoside reverse transcriptase inhibitor and protease inhibitor classes have been demonstrated to increase cardiovascular risk; however these effects are variable not only between classes but also between drugs in the same class. As newer therapies become available (in existing and new drug classes), the cardiovascular impact of these will need careful evaluation. Currently published guidelines suggest regular monitoring of cardiovascular risks (both before and after commencing ART) and pre-emptive treatment. Existing risk assessment tools have not been fully validated in an HIV setting and need to be used with caution. Lifestyle modification, in the first instance, and pharmacological intervention to reduce traditional risk factors are important management strategies. Initiating, or switching to, ART with a lower potential for metabolic derangement should also be considered.

HIV-1 antiretrovirals induce oxidant injury and increase intima-media thickness in an atherogenic mouse model

A growing body of evidence suggests HIV patients are at a greater risk for developing atherosclerosis. However, clinical investigations have generated conflicting results with regard to whether antiretrovirals are independently involved in the development of HIV-associated atherosclerosis. By administering antiretrovirals in an atherogenic mouse model, we determined whether two commonly prescribed antiretrovirals, the protease inhibitor indinavir and the nucleoside reverse transcriptase inhibitor AZT, can induce premature atherosclerosis. C57BL/6 mice were administered an atherogenic diet+/-AZT, indinavir, or AZT plus indinavir for 20 weeks. Aortic intima-media thickness (IMT) and cross-sectional area (CSA) were determined. Compared to controls, treatment with AZT, indinavir or AZT plus indinavir, significantly increased aortic IMT and CSA. This suggests that antiretrovirals can directly exacerbate atherogenesis, in the absence of interaction with a retroviral infection. To elucidate the role of oxidant injury in the drug-induced initiation of atherosclerosis, a separate group of mice were treated for 2 weeks with an atherogenic diet+/-AZT, indinavir or AZT plus indinavir. Aortic reactive oxygen species (ROS) production and glutathione/glutathione disulfide (GSH/GSSG) ratios, as well as plasma levels of 8-isoprostanes (8-iso-PGF(2alpha)) and lipids were determined. At 2 weeks, aortic ROS was increased and GSH/GSSG ratios were decreased in all antiretroviral treatment groups. Plasma 8-iso-PGF(2alpha) was increased in the AZT and AZT plus indinavir-treated groups. At 20 weeks, increased ROS production was maintained for the AZT and indinavir treatment groups, and increased 8-iso-PGF(2alpha) levels remained elevated in the AZT treatment group. Cholesterol levels were moderately elevated in the AZT and AZT plus indinavir-treated groups at 2 but not 20 weeks. Conversely, indinavir treatment increased plasma cholesterol at 20 but not 2 weeks. Thus, though effects on plasma lipid levels occurred, with effects of the individual antiretrovirals variable across the treatment period, there was consistent evidence of oxidant injury across both early and late time points. Together with the known metabolic abnormalities induced by antiretrovirals, drug-induced oxidant production may contribute to the development of antiretroviral-associated atherosclerosis.

Coronary and peripheral endothelial function in HIV patients studied with positron emission tomography and flow-mediated dilation: relation to hypercholesterolemia

BACKGROUND

The mechanisms underlying increased cardiovascular risk in HIV patients in antiretroviral therapy (ART) are not known. Our aim was to study the endothelial function of the coronary arteries by cardiac perfusion positron emission tomography (PET), in HIV patients with normal or high cholesterol levels. Flow mediated dilation (FMD) of the brachial artery and circulating endothelial markers were also assessed.

METHODS AND RESULTS

HIV patients in ART with total cholesterol <or= 5.5 mmol/L (215 mg/dL; n = 13) or total cholesterol >or= 6.5 mmol/L (254 mg/dL; n = 12) and healthy controls (n = 14) were included. (13)NH(3) perfusion PET, FMD, and measurement of plasma levels of E-Selectin, ICAM-1, VCAM-1, tPAI-1, and hs-CRP were performed. Baseline myocardial perfusion and the coronary flow reserve measured by PET (3.2 +/- 0.3, 3.2 +/- 0.3 and 3.0 +/- 0.3; ns) was similar in HIV patients with normal or high total cholesterol and controls. FMD did not differ between the groups and was 4.6 +/- 1.1%, 5.1 +/- 1.2%, and 4.6 +/- 0.8%, respectively. Increased levels of plasma E-Selectin, ICAM-1, tPAI-1, and hs-CRP were found in HIV patients when compared to controls (p < 0.05). E-Selectin and ICAM-1 levels were higher in HIV patients receiving protease inhibitors (PI) compared to those not receiving PI (p < 0.05). None of the measured endothelial biomarkers differed between the normal and high cholesterol HIV groups.

CONCLUSIONS

In ART-treated HIV patients with a low overall cardiovascular risk, no sign of endothelial dysfunction was found not even in hypercholesterolemic patients. Also, the increased level of plasma endothelial markers found in HIV patients was not related to hypercholesterolemia.

Drug/Drug interaction between lopinavir/ritonavir and rosuvastatin in healthy volunteers

OBJECTIVES

This open-label, single-arm, pharmacokinetic (PK) study in HIV-seronegative volunteers evaluated the bioequivalence of rosuvastatin and lopinavir/ritonavir when administered alone and in combination. Tolerability and lipid changes were also assessed.

METHODS

Subjects took 20 mg of rosuvastatin alone for 7 days, then lopinavir/ritonavir alone for 10 days, and then the combination for 7 days. Intensive PK sampling was performed on days 7, 17, and 24.

RESULTS

Twenty subjects enrolled, and PK data were available for 15 subjects. Geometric mean (+/-SD) rosuvastatin area under the concentration time curve (AUC)[0,tau] and maximum concentration (Cmax) were 47.6 ng.h/mL (+/-15.3) and 4.34 ng/mL (+/-1.8), respectively, when given alone versus 98.8 ng.h/mL (+/-65.5) and 20.2 ng/mL (+/-16.9) when combined with lopinavir/ritonavir (P < 0.0001). The geometric mean ratio was 2.1 (90% confidence interval [CI]: 1.7 to 2.6) for rosuvastatin AUC[0,tau] and 4.7 (90% CI: 3.4 to 6.4) for rosuvastatin Cmax with lopinavir/ritonavir versus rosuvastatin alone (P < 0.0001). There was 1 asymptomatic creatine phosphokinase elevation 17 times the upper limit of normal (ULN) and 1 liver function test elevation between 1.1 and 2.5 times the ULN with the combination.

CONCLUSIONS

Rosuvastatin low-density lipoprotein reduction was attenuated with lopinavir/ritonavir. Rosuvastatin AUC and Cmax were unexpectedly increased 2.1- and 4.7-fold in combination with lopinavir/ritonavir. Rosuvastatin and lopinavir/ritonavir should be used with caution until the safety, efficacy, and appropriate dosing of this combination have been demonstrated in larger populations.

The roles of HIV-1 proteins and antiretroviral drug therapy in HIV-1-associated endothelial dysfunction

Since the emergence of highly active antiretroviral therapy (HAART), human immunodeficiency virus-1 (HIV-1)-infected patients have demonstrated dramatic decreases in viral burden and opportunistic infections, and an overall increase in life expectancy. Despite these positive HAART-associated outcomes, it has become increasingly clear that HIV-1 patients have an enhanced risk of developing cardiovascular disease over time. Clinical studies are instrumental in our understanding of vascular dysfunction in the context of HIV-1 infection. However, most clinical studies often do not distinguish whether HIV-1 proteins, HAART, or a combination of these 2 factors cause cardiovascular complications. This review seeks to address the roles of both HIV-1 proteins and antiretroviral drugs in the development of endothelial dysfunction because endothelial dysfunction is the hallmark initial step of many cardiovascular diseases. We analyze recent in vitro and in vivo studies examining endothelial toxicity in response to HIV-1 proteins or in response to the various classes of antiretroviral drugs. Furthermore, we discuss the multiple mechanisms by which HIV-1 proteins and HAART injure the vascular endothelium in HIV-1 patients. By understanding the molecular mechanisms of HIV-1 protein- and antiretroviral-induced cardiovascular disease, we may ultimately improve the quality of life of HIV-1 patients through better drug design and the discovery of new pharmacological targets.

Insulin resistance predicts endothelial dysfunction and cardiovascular risk in HIV-infected persons on long-term highly active antiretroviral therapy

OBJECTIVE

Cardiovascular disease risk among persons with HIV is likely multifactorial, thus testing a variety of available noninvasive vascular ultrasound and other surrogate tests may yield differing results. To address this issue, we assessed multiple metabolic and clinical predictors of endothelial function and carotid intima-media thickness in HIV-infected subjects and compared results with HIV-negative controls.

DESIGN

Prospective, cross-sectional study of 50 HIV-infected, healthy adults on stable highly active antiretroviral therapy matched to 50 HIV-negative controls by age, sex, race, and body mass index.

METHODS

Flow-mediated vasodilation of the brachial artery, carotid intima-media thickness, dual energy X-ray absorptiometry (HIV-infected subjects), and fasting insulin, lipids, and oral glucose tolerance tests were performed. Results were compared between HIV-infected and control groups.

RESULTS

Fifty percent of subjects were African-American with 34% women. Among HIV-infected, mean CD4 cell count was 547 cells/microl; 90% had HIV RNA less than 50 copies/ml. There were no significant differences between HIV-infected and control subjects with regard to brachial artery flow-mediated vasodilation or carotid intima-media thickness. In multivariate analyses of the HIV cohort, independent predictors of endothelial dysfunction (lower flow-mediated vasodilation) were increasing insulin resistance, greater alcohol consumption, and higher baseline brachial artery diameter (P < 0.05); predictors of increased carotid intima-media thickness were hypertension, higher trunk/limb fat ratio, and insulin resistance (P < 0.05).

CONCLUSION

In this HIV cohort on modern highly active antiretroviral therapy with well controlled HIV, there were no significant differences with regard to preclinical markers of cardiovascular disease. Insulin resistance was a strong predictor of impaired brachial artery flow-mediated vasodilation and increased carotid intima-media thickness, and may be an important cardiovascular disease risk factor in the HIV population.

Long-term effects of pravastatin and fosinopril on peripheral endothelial function in albuminuric subjects

The purpose of this double-blind, randomized, placebo-controlled trial was to determine the long-term effects of pravastatin and fosinopril treatment on peripheral endothelial function in subjects with albuminuria. Subjects (mean age 51 years, 63% male) were randomized to pravastatin 40 mg or matching placebo and to fosinopril 20mg or matching placebo. Using high resolution ultrasound, flow-mediated dilation (FMD) and nitroglycerin-induced dilation (NID) was assessed at baseline and after 4 years of treatment in a total of 276 subjects. At baseline, mean+/-standard error FMD was 4.73+/-0.49% and NID was 10.86+/-0.67%. Pravastatin significantly reduced total cholesterol and LDL cholesterol (p<0.01) and randomization to pravastatin was associated with a non-significant improvement of 18.9% in FMD (+0.80+/-0.95, p=0.09), without a significant change in NID. Interestingly, pravastatin significantly increased FMD by 34.9% in men (+1.23, p=0.04), but only 1.1% in women (+0.06, p=0.95). Fosinopril was not associated with a change in FMD or NID despite significantly decreasing urinary albumin excretion, systolic and diastolic blood pressure (all p<0.01). In conclusion, after 4 years of follow-up, pravastatin treatment tended to increase FMD and this effect was predominantly present in men. Fosinopril treatment did not modify FMD during long-term follow-up.

Cross-sectional study of endothelial function in HIV-infected patients in Brazil

Antiretroviral therapy (ART) in HIV-infected patients has been associated with an increased risk of cardiovascular disease. This study evaluates vascular endothelial dysfunction of the peripheral circulation in Brazilian HIV-infected subjects on ART or naive to ART compared to a control group matched for age and body mass index (BMI). We performed a cross-sectional comparative study to measure postischemic peak flow-mediated dilation (FMD) of the brachial artery and the response to glyceryl trinitrate (GTN) in HIV-infected patients and healthy controls in Salvador, Bahia, Brazil. Endothelial vasomotor function was evaluated by assessing brachial artery FMD. Forty-four HIV-infected individuals (33 ARV treated and 11 ART naive) were compared to 25 healthy controls matched for age and BMI. FMD % was significantly lower for the ART-experienced patients compared to the ART-naive patients and was also significantly different from controls (ART experienced 8.2 +/- 6.0% vs. 19.3 +/- 4.8% vs. 23.3 +/- 6.1%), respectively (p < 0.0001). The cholesterol, triglyceride, and ALT levels were significantly higher in the ART-experienced group compared to the ART-naive and control subjects (p < 0.028); however, linear regression analysis revealed a statistically significant association of endothelial dysfunction as a dependent variable only with ARV treatment in HIV-infected subjects (p = 0.03). The association of endothelial dysfunction with ARV therapy in HIV-infected patients was independent of protease inhibitor-containing regimens or dyslipidemia. This dysfunction may contribute to the risk for HIV-associated atherosclerosis.