Intima-Media Thickness in the Carotid and Femoral Arteries for Detection of Arteriosclerosis in Human Immunodeficiency Virus-Positive Individuals

BACKGROUND

The prevalence of atherosclerosis is higher in HIV-positive people, who also experience it earlier than the general population.

OBJECTIVES

To assess and compare the prevalence of atherosclerosis evaluated by the intima-media thickness of carotid and femoral arteries, and by the ankle-brachial pressure index (ABPI) in HIV patients treated or not treated with protease inhibitors (PIs) and controls.

METHODS

Eighty HIV+ subjects (40 using PIs and 40 not using PIs) and 65 controls were included in the study. Atherosclerosis was diagnosed by (carotid and femoral) ITM measurement and ABPI. Classical risk factors for atherosclerosis and HIV were compared between the groups by statistical tests. A p ≤ 0.05 was considered significant.

RESULTS

An IMT > P75 or the presence of plaque was higher in the HIV+ than in the control group (37.5% vs 19%, p = 0.04). Comparative analysis showed a significant difference (p=0.014) in carotid IMT between HIV+ with PIs (0.71 ± 0.28 mm), without PIs 0.63 ± 0.11 mm and, and controls (0.59 ± 0.11 mm). There was no significant difference in femoral IMT between the groups or in ABPI between HIV+ subjects and controls. However, a significant difference (p=0.015) was found between HIV+ patients not treated with PIs (1.17 [1.08 - 1.23]), and controls 1.08 [1.07 - 1.17]).

CONCLUSION

In HIV patients, atherosclerosis is more prevalent and seems to occur earlier with particular characteristics compared with HIV-negative subjects.

Role of systemic inflammation scores for prediction of clinical outcomes in patients treated with atazanavir not boosted by ritonavir in the Italian MASTER cohort

Background

Atazanavir (ATV) not boosted by ritonavir (uATV) has been frequently used in the past for switching combination antiretroviral therapy (cART). However, the clinical outcomes and predictors of such strategy are unknown.

Methods

An observational study was carried out on the Italian MASTER, selecting HIV infected patients on cART switching to an uATV-containing regimen. Baseline was set as the last visit before uATV initiation. In the primary analysis, a composite clinical end-point was defined as the first occurring of any condition among: liver, cardiovascular, kidney, diabetes, non AIDS related cancer or death events. Incidence of AIDS events and incidence of composite clinical end-point were estimated. Kaplan-Meier and multivariable Cox regression analysis were used to assess predictors of the composite clinical end-point.

Results

436 patients were observed. The majority of patients were males (61.5%) and Italians (85.3%), mean age was 42.7 years (IQR: 37.7–42), the most frequent route of transmission was heterosexual intercourse (47%), followed by injection drug use (25%) and homosexual contact (24%); the rate of HCV-Ab positivity was 16.3%. Patients were observed for a median time of 882 days (IQR: 252-1,769) under uATV. We recorded 93 clinical events (3 cardiovascular events, 20 kidney diseases, 33 liver diseases, 9 non AIDS related cancers, 21 diabetes, 7 AIDS events), and 19 deaths, accounting for an incidence of 3.7 (composite) events per 100 PYFU. At multivariable analysis, factors associated with the composite clinical end-point were intravenous drug use as risk factor for HIV acquisition vs. heterosexual intercourses [HR: 2.608, 95% CI 1.31–5.19, p = 0.0063], HIV RNA per Log₁₀ copies/ml higher [HR: 1.612, 95% CI 1.278–2.034, p < 0.0001], number of switches in the nucleoside/nucleotide (NRTI) backbone of cART (performed to compose the uATV regimen under study or occurred in the past) per each more [HR: 1.085, 95% CI 1.025–1.15, p = 0.0051], Fib-4 score per unit higher [HR: 1.03, 95% CI 1.018–1.043, p < 0.0001] and Neutrophil/lymphocytes ratio (NLR inflammation score) per Log₁₀ higher [HR: 1.319, 95% CI 1.047–1.662, p = 0.0188].

Conclusions

Intravenous drug users with high HIV RNA, high Fib-4 levels and more heavily exposed to antiretroviral drugs appeared to be more at risk of clinical events. Interestingly, high levels of inflammation measured through NLR, were also associated with clinical events. So, these patients should be monitored more strictly.

HIV Infection and Primary Prevention of Cardiovascular Disease: Lights and Shadows in the HAART Era

With the progressive increase in life-expectancy of human immunodeficiency virus (HIV)-positive patients in the "highly active antiretroviral therapy" (HAART) era, co-morbidities, particularly cardiovascular (CV) diseases (CVD) are emerging as an important concern. The pathophysiology of CVD in this population is complex, due to the interaction of classical CV risk factors, viral infection and the effects of antiretroviral therapy (ARV). The role of ARV drugs in HIV is double edged. While these drugs reduce systemic inflammation, an important factor in CV development, they may at the same time be proatherogenic by inducing dyslipidemia, body fat redistribution and insulin resistance. In these patients primary prevention is challenging, considering the lower median age at which acute coronary syndromes occur. Furthermore prevention is still limited by the lack of robust evidence-based, HIV-specific recommendations. Therefore we performed a comprehensive evaluation of the literature to analyze current knowledge on CVD prevalence in HIV-infected patients, traditional and HIV-specific risk factors and risk stratification, and to summarize the recommendations for primary prevention of CVD in this HIV population.

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.

Factors involved in continuance of atazanavir-based regimens: Results from a cohort of HIV1-positive patients

We evaluated predictive factors involved in durability and therapeutic failure of atazanavir (ATV)-based antiretroviral regimens with or without ritonavir (r) in real life setting. This retrospective study of HIV-1-positive patients evaluated the factors related to ATV continuance and the time-dependent probability of therapeutic failure (HIV-RNA >200 copies/mL and concomitant discontinuation of ATV). We also investigated the rate of therapeutic failure and the variations in total bilirubin levels from starting unboosted ATV-based regimens. The study involved 1030 patients: 183 treatment-naïve patients (17.8%) started ATV/r (17 subsequently switched to unboosted ATV); 653 (63.4%) switched to ATV/r from previous antiretroviral regimens (121 subsequently switched to unboosted ATV); and 194 (18.8%) switched to unboosted ATV from previous ATV-free regimens. The median ATV follow-up was 28 months (interquartile range 7-56). The risk of ATV discontinuation was significantly lower in patients switched to unboosted ATV from ATV/r (HR 0.45; p < 0.0001). The discontinuation of ATV correlated with female gender (HR 1.26; p = 0.035), use of a zidovudine/didanosine/stavudine containing backbone (HR 1.8; p = 0.004), and a baseline CD4+ cell counts of <200/μL (HR 1.54; p = 0.003), the last of which was also associated with a higher risk of therapeutic failure (HR 2.42; p = 0.001). Total bilirubin levels were significantly lower in the patients switching from ATV/r to unboosted ATV. Unboosted ATV-based therapies are safe and effective options in patients whose immuno-virological conditions are stable, and allow the long-term survival of ATV-containing regimens.

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.

Insulin resistance in treated HIV infection

Insulin resistance (IR) was one of the first metabolic complications reported with highly active antiretroviral therapy for HIV infection. It continues to be of concern despite the introduction of newer antiretrovirals with safer metabolic profiles and is associated with inflammation and the development of diabetes mellitus. As the HIV-infected population ages, the prevalence of IR is likely to rise. Specific antiretrovirals can increase insulin resistance through two principal mechanisms, either directly by interfering with insulin signalling at the cellular level or indirectly as a consequence of defects in lipid metabolism (lipotoxocity) arising from antiretroviral toxicities such as the IR observed in those with HIV-associated lipodystrophy. There is considerable overlap between different antiretrovirals in their propensity to cause IR making it more difficult to attribute development of IR to a particular antiretroviral medication. In addition, in the setting of a generalised epidemic of obesity that exists in many populations worldwide, HIV-infected patients may be more prone to the consequences of antiretroviral-induced insulin resistance and diabetes mellitus. Optimal screening and treatment strategies for IR in treated HIV infection have not been established. In this article we review current opinion on insulin resistance in HIV and identify potential areas for future research.

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.

Lipid Metabolism and Cardiovascular Risk in HIV-1 Infection and HAART: Present and Future Problems

Many infections favor or are directly implicated with lipid metabolism perturbations and/or increased risk of coronary heart disease (CHD). HIV itself has been shown to increase lipogenesis in the liver and to alter the lipid profile, while the presence of unsafe habits, addiction, comorbidities, and AIDS-related diseases increases substantially the risk of cardiovascular disease (CVD) in the HIV-infected population. Antiretroviral therapy reduces such stimuli but many drugs have intrinsic toxicity profiles impacting on metabolism or potential direct cardiotoxicity. In a moment when the main guidelines of HIV therapy are predating the point when to start treating, we mean to highlight the contribution of HIV-1 to lipid alteration and inflammation, the impact of antiretroviral therapy, the decisions on what drugs to use to reduce the probability of having a cardiovascular event, the increasing use of statins and fibrates in HIV-1 infected subjects, and finally the switch strategies, that balance effectiveness and toxicity to move the decision to change HIV drugs. Early treatment might reduce the negative effect of HIV on overall cardiovascular risk but may also evidence the impact of drugs, and the final balance (reduction or increase in CHD and lipid abnormalities) is not known up to date.

HIV-protease inhibitors suppress skeletal muscle fatty acid oxidation by reducing CD36 and CPT1 fatty acid transporters

Infection with human immunodeficiency virus (HIV) and treatment with HIV-protease inhibitor (PI)-based highly active antiretroviral therapies (HAART) is associated with dysregulated fatty acid and lipid metabolism. Enhanced lipolysis, increased circulating fatty acid levels, and hepatic and intramuscular lipid accumulation appear to contribute to insulin resistance in HIV-infected people treated with PI-based HAART. However, it is unclear whether currently prescribed HIV-PIs directly alter skeletal muscle fatty acid transport, oxidation, and storage. We find that ritonavir (r, 5micromol/l) plus 20micromol/l of atazanavir (ATV), lopinavir (LPV), or darunavir (DRV) reduce palmitate oxidation(16-21%) in differentiated C2C12 myotubes. Palmitate oxidation was increased following exposure to high fatty acid media but this effect was blunted when myotubes were pre-exposed to the HIV-PIs. However, LPV/r and DRV/r, but not ATV/r suppressed palmitate uptake into myotubes. We found no effect of the HIV-PIs on FATP1, FATP4, or FABPpm but both CD36/FAT and carnitine palmitoyltransferase 1 (CPT1) were reduced by all three regimens though ATV/r caused only a small decrease in CPT1, relative to LPV/r or DRV/r. In contrast, sterol regulatory element binding protein-1 was increased by all 3 HIV-PIs. These findings suggest that HIV-PIs suppress fatty acid oxidation in murine skeletal muscle cells and that this may be related to decreases in cytosolic- and mitochondrial-associated fatty acid transporters. HIV-PIs may also directly impair fatty acid handling and partitioning in skeletal muscle, and this may contribute to the cluster of metabolic complications that occur in people living with HIV.

A formalized teaching, practice, and research partnership with the Veterans Affairs North Texas Health Care System: a model for advancing academic partnerships

In 1999, the Texas Tech University Health Sciences Center School of Pharmacy expanded its Dallas/Fort Worth presence by creating a regional campus for pharmacy students in their third and fourth years (P3 and P4 years) of the program. This expansion was driven by the need for additional practice sites. The VANTHCS was an obvious choice for the school due to the similarity of missions for clinical practice, education, and research. The VANTHCS and pharmacy school renovated a 4,000 square foot building, which includes classrooms, conference rooms, a student lounge, and faculty offices (expanded to 8,000 square feet in 2003). To date, the school has invested $1 million in the building. From a practice perspective, VANTHCS purchases faculty professional services from the school to augment its clinical specialist staff. These professional practice contracts provide VANTHCS with 12 additional clinical pharmacy specialists serving 50% of their time in multiple specialty areas. The collaboration has also allowed for expansion of clinical teaching, benefitting both institutions. In addition to the pharmacy student interns on P3 and P4 practice experiences, the collaboration allows for 8 to 10 postgraduate pharmacy residents to train with VANTHCS clinical specialists and school faculty members each year. The VANTHCS/pharmacy school collaboration has clearly enhanced the ability of both institutions to exceed their teaching, research, and practice goals in a cost-effective manner.

Efficacy and safety of atazanavir-ritonavir plus abacavir-lamivudine or tenofovir-emtricitabine in patients with hyperlipidaemia switched from a stable protease inhibitor-based regimen including one thymidine analogue

Randomized, open-label, prospective clinical trial assessing efficacy and safety on hyperlipidemia of a switching from a regimen including one protease inhibitor and one thymidine analogue to atazanavir/ritonavir plus abacavir/lamivudine or tenofovir/emtricitabine. Adult HIV-infected patients on their first antiretroviral therapy (of at least 48-week duration), including one protease inhibitor and zidovudine or stavudine, with stable immunovirologic features, and having diagnosis of persisting hyperlipidemia, were randomized to replace current treatment with atazanavir/ritonavir plus abacavir/lamivudine (arm A) or tenofovir/emtricitabine (arm B), and were followed for 48 weeks. Eighty-nine patients were enrolled: 42 patients were randomized to arm A, and 47 to arm B. At the end of the 48-week follow-up, incidence of virologic failure was comparable in both arms, and associated with a poor drug compliance. Increase in CD4 lymphocyte count was significantly higher in arm A after a 24-week study period (62.5 versus 39.2 x 10(6) cells/L; p < 0.05), while immunologic responses were comparable at the end of 48-week follow-up (91.5 versus 83.6; p > 0.05). A statistically significant reduction (-15.4%) in mean triglyceridaemia versus respective baseline values was reported in both groups (p < 0.05), without statistically significant difference between arm A and B. Similar results were reported for total cholesterol and low-density lipoprotein (LDL) cholesterol levels. Safety and tolerability profiles were comparable in both groups. Switching from a protease inhibitor- and thymidine analogue-based antiretroviral regimen to atazanavir/ritonavir plus abacavir/lamivudine or tenofovir/emtricitabine proved effective in the management of hyperlipidemia, without significant differences in lipid-lowering effect, virologic efficacy, and safety profile between these regimens.

Efficacy and safety of ritonavir-boosted and unboosted atazanavir among antiretroviral-naïve patients

PURPOSE

Evaluate responses and safety of ritonavir-boosted atazanavir ("boosted atazanavir") compared to unboosted atazanavir among antiretroviral-naïve patients in the clinical managed care setting.

METHOD

Observational cohort analysis of atazanavir use (comparing ritonavir-boosted to non-boosted) at Kaiser Permanente and Group Health Cooperative from 2003 to 2006. Antiretroviral-naïve patients initiating atazanavir were followed through 52 weeks of treatment.

RESULTS

443 patients were prescribed atazanavir (69 non-boosted; 15.5%). Boosted and non-boosted atazanavir groups were similar with respect to gender and age. Boosted atazanavir use was associated with greater odds achieving HIV RNA <400 c/mL (odds ratio [OR] = 3.24, p = .008), greater decrease in HIV RNA (-0.37 log10/mL, p = .03), greater increase in CD4 T-cell count (+59 cells/microL, p = .01), and greater increase in total bilirubin (+1.21 mg/dL as opposed to +0.56 mg/dL, p .001). There were no statistically significant differences for glucose, liver transaminases, total cholesterol, or LDL cholesterol elevations. There were greater odds of maximal viral control when atazanavir was combined with tenofovir or zidovudine in combination with lamivudine (or emtricitabine).

CONCLUSIONS

Ritonavir-boosted atazanavir is associated with greater virologic control and immune response through 52 weeks compared to non-boosted atazanavir, without greater risk of adverse events except elevated bilirubin. Thus, ritonavir-boosted atazanavir is the preferred method of prescribing atazanavir.

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.