Preclinical atherosclerosis due to HIV infection: carotid intima-medial thickness measurements from the FRAM study

Management of dyslipidemia in HIV-infected patients

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

High rate of coronary artery abnormalities in adolescents and young adults infected with human immunodeficiency virus early in life

We completed a cross-sectional study of individuals infected with human immunodeficiency virus in early childhood using cardiac magnetic resonance imaging and magnetic resonance angiography. Coronary artery abnormality (CAA) was defined by the presence of luminal narrowing and irregularity of the coronary vessel wall. More than 50% of participants (14/27) had evidence of CAA. Individuals had a high rate of CAA, suggesting possible early atherosclerosis.

Hypertension and obesity as cardiovascular risk factors among HIV seropositive patients in Western Kenya

BACKGROUND

There is increased risk of cardiovascular disease among HIV seropositive individuals. The prevalence of HIV is highest in sub-Saharan Africa; however, HIV-related cardiovascular risk research is largely derived from developed country settings. Herein, we describe the prevalence of hypertension and obesity in a large HIV treatment program in Kenya.

METHODS

We performed a retrospective analysis of the electronic medical records of a large HIV treatment program in Western Kenya between 2006 and 2009. We calculated the prevalence of hypertension and obesity among HIV+ adults as well as utilized multiple logistic regression analyses to examine the relationship between clinical characteristics, HIV-related characteristics, and hypertension.

RESULTS

Our final sample size was 12,194. The median systolic/diastolic blood pressures were similar for both sexes (male: 110/70 mmHg, female: 110/70 mmHg). The prevalence of hypertension among men and women were 11.2% and 7.4%, respectively. Eleven percent of men and 22.6% of women were overweight/obese (body mass index ≥25 kg/m(2)). Ordinal logistic regression analyses showed that overweight/obesity was more strongly associated with hypertension among HIV+ men (OR 2.41, 95% CI 1.88-3.09) than a higher successive age category (OR 1.62, 95% CI 1.40-1.87 comparing 16-35, 36-45 and >45 years categories). Among women, higher age category and overweight/obesity were most strongly associated with hypertension (age category: OR 2.21, 95% CI 1.95-2.50, overweight/obesity: OR 1.80, 95% CI 1.50-2.16). Length of time on protease inhibitors was not found to be related to hypertension for men (OR 1.62, 95% CI 0.42-6.20) or women (OR 1.17, 95% CI 0.37-2.65) after adjustment for CD4 count, age and BMI.

CONCLUSION

In Western Kenya, there is a high prevalence of hypertension and overweight/obesity among HIV+ patients with differences observed between men and women. The care of HIV+ patients in sub-Saharan Africa should also include both identification and management of associated cardiovascular risk factors.

Growing Old with HIV

The intersection of chronic HIV infection, its treatment, and lifestyle with aging has become a topic of considerable fascination during this, the third decade of the AIDS epidemic. An understanding of the pathophysiology of this intersection may provide valuable insights into our general understanding of human aging. This review summarizes the results of recent publications that may have considerable impact on screening and management strategies in the aging HIV-infected population.

Association between use of HMG CoA reductase inhibitors and mortality in HIV-infected patients

INTRODUCTION

HIV infection is a disease associated with chronic inflammation and immune activation. Antiretroviral therapy reduces inflammation, but not to levels in comparable HIV-negative individuals. The HMG-coenzyme A reductase inhibitors (statins) inhibit several pro-inflammatory processes and suppress immune activation, and are a logical therapy to assess for a possible salutary effect on HIV disease progression and outcomes.

METHODS

Eligible patients were patients enrolled in the Johns Hopkins HIV Clinical Cohort who achieved virologic suppression within 180 days of starting a new highly active antiretroviral therapy (HAART) regimen after January 1, 1998. Assessment was continued until death in patients who maintained a virologic suppression, with right-censoring of their follow-up time if they had an HIV RNA > 500 copies/ml. Cox proportional hazards regression was used to assess statin use as a time-varying covariate, as well as other demographic and clinical factors.

RESULTS

A total of 1538 HIV-infected patients fulfilled eligibility criteria, of whom 238 (15.5%) received a statin while taking HAART. There were 85 deaths (7 in statin users, 78 in non-users). By multivariate Cox regression, statin use was associated with a relative hazard of 0.33 (95% CI: 0.14, 0.76; P =  0.009) after adjusting for CD4, HIV-1 RNA, hemoglobin and cholesterol levels at the start of HAART, age, race, HIV risk group, prior use of ART, year of HAART start, NNRTI vs. PI-based ART, prior AIDS-defining illness, and viral hepatitis coinfection. Malignancy, non-AIDS-defining infection and liver failure were particularly prominent causes of death.

DISCUSSION

Statin use was associated with significantly lower hazard of dying in these HIV-infected patients who were being effectively treated with HAART as determined by virologic suppression. Our results suggest the need for confirmation in other observational cohorts, and if confirmed, the need for a clinical trial of statin use in HIV infection.

Regional fat deposition and cardiovascular risk in HIV infection: the FRAM study

HIV-infected individuals are at increased risk for cardiovascular disease (CVD) and lipodystrophy, but the relationship between regional adipose tissue (AT) depots and CVD risk is not well described. We determined regional AT volumes and CVD risk in an analysis of 586 HIV-infected and 280 control FRAM study subjects using whole-body magnetic resonance imaging (MRI) and the Framingham Risk Score (FRS). Median FRS and FRS >10% were higher in HIV than control men (4.7% vs. 3.7%, p=0.0002; 16% vs. 4%, p<0.0001). HIV and control women had similarly low FRS (1.1% vs. 1.2%, p=0.91). In controls, total AT and all regional AT depots showed strong positive correlations with FRS (p<0.001) in men and weaker positive correlations in women. Greater visceral AT (VAT) and lower leg subcutaneous AT (SAT) volumes were associated with elevated FRS in HIV subjects with a trend for upper trunk SAT. Controls in the lowest quartile of leg SAT had the lowest FRS (1.5%), whereas HIV with similarly low leg SAT had the highest FRS (4.0%, p<0.001 vs. controls). Increased VAT is associated with CVD risk, but the risk is higher in HIV-infected individuals relative to controls at every level of VAT. Peripheral lipoatrophy (as measured by leg SAT) is associated with striking increased CVD risk in HIV-infected patients even after controlling for VAT, whereas low leg SAT is associated with low CVD risk in controls.

Cardiovascular implications of HIV-induced dyslipidemia

Cardiovascular disease (CVD) is currently the second most frequent cause of death (after cancer) among HIV-positive subjects. The clinical use of highly active antiretroviral therapy (HAART) has dramatically reduced mortality and morbidity in HIV-positive population, leading to prolonged and improved quality of life. However, as mortality and morbidity from AIDS-related conditions improve, CVD assumes increasing magnitude. It is estimated that by 2015 more than 50% of HIV-positive patients will be older than 50 years. Since age is a major unmodifiable cardiovascular risk factor, the risk for CVD in this population will significantly and progressively increase in the near future. A large part of the risk for cardiovascular events appears to be a result of lipid abnormalities characterizing HIV-positive persons. This review focuses on HIV-associated lipid abnormalities and CVD. Lipid abnormalities may be related to either viral infection, HAART or both. Dyslipidemia characterizing HIV-infected patients has become a therapeutic target to reduce cardiovascular risk of HIV-treated patients. HAART-treated patients show an atherogenic lipid profile comprised of low HDL-cholesterol levels, hypertrigliceridemia and increased levels of small-LDL particles. Current guidelines for the treatment of dyslipidemia and reducing cardiovascular risk in HIV-positive patients suggest that when lifestyle modifications (i.e., diet and exercise) and switching antiretroviral therapy are not enough, statins should be the first-line therapy for dyslipidemia. HDL raising interventions (niacin and fibrates) should be considered to raise HDL levels and lower triglyceride in HIV-infected patients. Implications of lipid-related interventions in HIV-treated patients to avoid drug interactions and their adverse effects are also discussed.

Longitudinal assessment of metabolic abnormalities in adolescents and young adults with HIV-infection acquired perinatally or in early childhood

Metabolic complications of HIV pose challenges for health maintenance among young adults who acquired HIV in early childhood. Between July 2004 and July 2009, we evaluated 47 HIV-infected subjects who acquired HIV in early life. Participants completed glucose tolerance testing; insulin, lipid, urine albumin, and creatinine determinations; and dual-energy x-ray absorptiometry scans. Longitudinal data were available for 39 subjects; duration of follow-up was 26.4 ± 16.8 months. At baseline, participants were 17.1 ± 3.9 years old; and duration of antiretroviral therapy was 12.7 ± 3.4 years. CD4 count was 658 ± 374 cells per cubic millimeter, and 55% had undetectable viral load. Impaired glucose tolerance was present in 15%; 33% had insulin resistance (homeostasis model assessment of insulin resistance >4.0). Furthermore, 52% had triglycerides of at least 150 mg/dL, 36% had high-density lipoprotein cholesterol less than 40 mg/dL, 18% had low-density lipoprotein cholesterol of at least 130 mg/dL, and 25% had total cholesterol of at least 200 mg/dL. Microalbuminuria was present in 15% of participants and was inversely correlated with CD4% (P = .001). During follow-up, more than one third remained insulin resistant; lipid parameters tended to improve. There were significant increases in body mass index (P = .0002), percentage leg fat (P = .008), and percentage trunk fat (P = .002). Impaired glucose tolerance, insulin resistance, dyslipidemia, and microalbuminuria are common among young adults with HIV. Long-term exposure to therapy may translate into substantial persistent metabolic risk.

HIV-1 and recombinant gp120 affect the survival and differentiation of human vessel wall-derived mesenchymal stem cells

BACKGROUND

HIV infection elicits the onset of a progressive immunodeficiency and also damages several other organs and tissues such as the CNS, kidney, heart, blood vessels, adipose tissue and bone. In particular, HIV infection has been related to an increased incidence of cardiovascular diseases and derangement in the structure of blood vessels in the absence of classical risk factors. The recent characterization of multipotent mesenchymal cells in the vascular wall, involved in regulating cellular homeostasis, suggests that these cells may be considered a target of HIV pathogenesis. This paper investigated the interaction between HIV-1 and vascular wall resident human mesenchymal stem cells (MSCs).

RESULTS

MSCs were challenged with classical R5 and X4 HIV-1 laboratory strains demonstrating that these strains are able to enter and integrate their retro-transcribed proviral DNA in the host cell genome. Subsequent experiments indicated that HIV-1 strains and recombinant gp120 elicited a reliable increase in apoptosis in sub-confluent MSCs. Since vascular wall MSCs are multipotent cells that may be differentiated towards several cell lineages, we challenged HIV-1 strains and gp120 on MSCs differentiated to adipogenesis and endotheliogenesis. Our experiments showed that the adipogenesis is increased especially by upregulated PPARγ activity whereas the endothelial differentiation induced by VEGF treatment was impaired with a downregulation of endothelial markers such as vWF, Flt-1 and KDR expression. These viral effects in MSC survival and adipogenic or endothelial differentiation were tackled by CD4 blockade suggesting an important role of CD4/gp120 interaction in this context.

CONCLUSIONS

The HIV-related derangement of MSC survival and differentiation may suggest a direct role of HIV infection and gp120 in impaired vessel homeostasis and in genesis of vessel damage observed in HIV-infected patients.

HIV infection and cocaine use induce endothelial damage and dysfunction in African Americans

BACKGROUND

Clinical and epidemiological evidence suggests that HIV infection and cocaine use are associated with an increased risk of premature atherosclerosis. The underlying mechanisms linking HIV infection and cocaine use with early atherosclerosis remain elusive.

METHODS AND RESULTS

Endothelin-1 (ET-1) levels in 360 African American participants in Baltimore, Maryland were measured. Quantile regression analysis was performed to examine the associations between ET-1, HIV infection, cocaine use, and other relevant clinical factors. The median of ET-1 in plasma, (1.05 pg/mL with interquartile range: 0.73, 1.40) for those with HIV infection was significantly higher than values for those without HIV infection (0.74 pg/mL with interquartile range: 0.61, 0.93). The median of ET-1 was markedly higher in chronic cocaine users (0.96 pg/mL with interquartile range: 0.71, 1.36) than that in non-cocaine users (0.72 pg/mL with interquartile range: 0.58, 1.06). Multivariate quantile regression suggested that HIV infection and duration of cocaine use were independently associated with plasma ET-1 levels after controlling for potential confounding factors.

CONCLUSIONS

This study may provide insight into the mechanism of premature atherosclerosis in HIV-infected cocaine users and suggest that measurement of ET-1 in plasma can be used as a marker of early atherosclerosis in HIV infected patients and cocaine users.

HIV infection, inflammation, immunosenescence, and aging

Although antiretroviral therapy for HIV infection prevents AIDS-related complications and prolongs life, it does not fully restore health. Long-term treated patients remain at higher than expected risk for a number of complications typically associated with aging, including cardiovascular disease, cancer, osteoporosis, and other end-organ diseases. The potential effect of HIV on health is perhaps most clearly exhibited by a number of immunologic abnormalities that persist despite effective suppression of HIV replication. These changes are consistent with some of the changes to the adaptive immune system that are seen in the very old ("immunosenescence") and that are likely related in part to persistent inflammation. HIV-associated inflammation and immunosenescence have been implicated as causally related to the premature onset of other end-organ diseases. Novel therapeutic strategies aimed at preventing or reversing these immunologic defects may be necessary if HIV-infected patients are to achieve normal life span.

Approach to dyslipidemia, lipodystrophy, and cardiovascular risk in patients with HIV infection

There is a significant prevalence (20%–80% depending on the population and the study) of lipid disorders and other cardiovascular risk factors in people living with HIV infection. This review focuses on HIV and HIV treatment–associated metabolic and cardiovascular concerns, including dyslipidemias, lipodystrophy syndromes, endothelial dysfunctions, and associated metabolic events such as insulin resistance. Emerging hypotheses of the underlying pathophysiology of these issues, with impact on selection of specific antiretroviral treatment (ART) strategies, therapy, and preventive approaches to decreasing cardiovascular risk and other problems associated with these syndromes are discussed. Screening for cardiovascular risk as part of the decision of starting antiretroviral therapy, and during care of patients with HIV regardless of ART therapy status, is suggested with particular areas of focus. Statins, other hyperlipidemic therapies, treatment for specific problems arising due to lipodystrophy, and implications on ART selection to avoid drug interactions and adverse effects are also discussed.

Reduced kidney function and preclinical atherosclerosis in HIV-infected individuals: the study of fat redistribution and metabolic change in HIV infection (FRAM)

BACKGROUND/AIMS

Reduced kidney function and albuminuria are associated with higher risk for cardiovascular disease (CVD) and mortality in HIV-infected individuals. We investigated whether reduced estimated glomerular filtration rate (eGFR) and albuminuria are associated with subclinical vascular disease, as assessed by carotid intima-medial thickness (cIMT).

METHODS

Cross-sectional analysis of 476 HIV-infected individuals without clinical evidence of CVD enrolled in the Fat Redistribution and Metabolic Change in HIV infection (FRAM) study, using multivariable linear regression. eGFR(Cys) and eGFR(Cr) were calculated from cystatin C and creatinine levels. Albuminuria was defined as a positive urine dipstick (≥ 1+) or urine albumin-to-creatinine ratio ≥ 30 mg/g. Common and internal cIMT were measured by high-resolution B-mode ultrasound.

RESULTS

In unadjusted analyses, eGFR(Cys) and eGFR(Cr) were strongly associated with com- mon and internal cIMT. Each 10 ml/min/1.73 m2 decrease in eGFR(Cys) and eGFR(cr) was associated with a 0.008 mm higher common cIMT (p = 0.003, p = 0.01) and a 0.024 and 0.029 mm higher internal cIMT (p = 0.003), respectively. These associations were eliminated after adjustment for age, gender, and race. Albuminuria showed little association with common or internal cIMT in all models.

CONCLUSIONS

In HIV-infected individuals without prior CVD, reduced kidney function and albuminuria were not independently associated with subclinical vascular disease, as assessed by cIMT. These results suggest that research should focus on searching for novel mechanisms by which kidney disease confers cardiovascular risk in HIV-infected individuals.

Combination antiretroviral therapy

Combination antiretroviral therapy (cART) was one of the greatest achievements in medicine in the twentieth century. It has rapidly evolved during the last 10 years from suboptimal monotherapy to an effective triple therapy that can change the natural history of HIV-1 infection from a deadly disease to a chronic, manageable condition. However, a dreadful toll of long-term toxicity was experienced by HIV-1-infected patients in the cART era. We have recently entered in a new phase of cART, in which efficacy has been increased and toxicity minimized. Currently, the greatest challenge is to make cART available to everybody who needs it with the future prospects of HIV-1 eradication.

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

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

HIV-1 and the macrophage

Macrophages and CD4+ T cells are natural target cells for HIV-1, and both cell types contribute to the establishment of the viral reservoir that is responsible for continuous residual virus replication during antiretroviral therapy and viral load rebound upon treatment interruption. Scientific findings that support a critical role for the infected monocyte/macrophage in HIV-1-associated diseases, such as neurological disorders and cardiovascular disease, are accumulating. To prevent or treat these HIV-1-related diseases, we need to halt HIV-1 replication in the macrophage reservoir. This article describes our current knowledge of how monocytes and certain macrophage subsets are able to restrict HIV-1 infection, in addition to what makes macrophages respond less well to current antiretroviral drugs as compared with CD4+ T cells. These insights will help to find novel approaches that can be used to meet this challenge.

Cardiovascular implications from untreated human immunodeficiency virus infection

Atherosclerotic cardiovascular disease (CVD) has become an important cause of morbidity and mortality among individuals with human immunodeficiency virus (HIV) infection with access to antiretroviral medications, as the risk for AIDS has fallen and life expectancy improved. Traditional CVD risk factors are often more common among individuals with HIV infection, and traditional prevention strategies remain important. Recent data have revealed that untreated HIV infection itself amplifies additional pro-atherogenic mechanisms related to immune activation, inflammation, coagulation, and lipoprotein particle changes (e.g. high-density lipoprotein particles). Some of these mechanisms are attenuated, though incompletely, with antiretroviral therapy (ART)-related suppression of HIV replication. Exposure to ART is also associated with variable toxicity that may simultaneously decrease (via viral suppression) and increase CVD risk. Ultimately, additional adjunctive treatment will be needed to mitigate premature CVD risk among contemporary HIV-infected patients with access to ART.

T cell activation and senescence predict subclinical carotid artery disease in HIV-infected women

Background. Individuals infected with human immunodeficiency virus (HIV) have increased risk of cardiovascular events. It is unknown whether T cell activation and senescence, 2 immunologic sequelae of HIV infection, are associated with vascular disease among HIV-infected adults.

Methods. T cell phenotyping and carotid ultrasound were assessed among 115 HIV-infected women and 43 age- and race/ethnicity-matched HIV-uninfected controls participating in the Women's Interagency HIV Study. Multivariate analyses were used to assess the association of T cell activation (CD38⁺HLA-DR⁺) and senescence (CD28⁻CD57⁺) with subclinical carotid artery disease.

Results. Compared with HIV-uninfected women, frequencies of CD4⁺CD38⁺HLA-DR⁺, CD8⁺CD38⁺HLA-DR⁺, and CD8⁺CD28⁻CD57⁺ T cells were higher among HIV-infected women, including those who achieved viral suppression while receiving antiretroviral treatment. Among HIV-infected women, adjusted for age, antiretroviral medications, and viral load, higher frequencies of activated CD4⁺ and CD8⁺ T cells and immunosenescent CD8⁺ T cells were associated with increased prevalence of carotid artery lesions (prevalence ratio_lesions associated with activated CD4⁺ T cells, 1.6 per SD [95% confidence interval {CI}, 1.1–2.2]; P = .02; prevalence ratio_lesions associated with activated CD8⁺ T cells, 2.0 per SD [95% CI, 1.2–3.3]; P < .01; prevalence ratio_lesions associated with senescent CD8⁺ T cells, 1.9 per SD [95% CI, 1.1–3.1]; P = .01).

Conclusions. HIV-associated T cell changes are associated with subclinical carotid artery abnormalities, which may be observed even among those patients achieving viral suppression with effective antiretroviral therapy.

Tobacco use and nicotine dependence among HIV-infected and uninfected injection drug users

INTRODUCTION

Urban U.S. populations are burdened by intersecting epidemics of HIV infection, injection drug use, and cigarette smoking. Given the substantial morbidity attributable to tobacco in these populations, we characterized smoking behaviors, nicotine addiction, and tobacco exposure among HIV-infected and HIV-uninfected injection drug users (IDUs) in Baltimore, Maryland.

METHODS

Smoking behaviors among participants in the ALIVE Study were assessed using interviewer-administered questionnaires. Smoking history and nicotine dependence (Fagerstrom Index scores) were compared by HIV and drug injecting status. Serum cotinine (a nicotine metabolite) was measured for a sample of participants by enzyme immunoassay.

RESULTS

Among 1052 participants (29.7% HIV-infected, 39.8% active injectors), 85.2% were current smokers and 9.3% were former smokers. Smoking prevalence, age at smoking initiation, and cumulative tobacco exposure were similar by HIV status. Median Fagerstrom scores of 4 for HIV-infected and HIV-uninfected smokers indicated moderate nicotine dependence. Daily cigarette consumption was identical by HIV status (median 10 cigarettes), although HIV-infected participants were less likely to smoke 1+ pack daily compared to HIV-uninfected participants (18.0% vs. 26.9%, p=0.001). Compared to former injectors, active injectors had higher smoking prevalence (90.5% vs. 81.7%, p=0.0001), greater daily cigarette consumption (30.7% vs. 19.6% smoked 1+ pack daily, p=0.0001), and slightly higher Fagerstrom scores (median 5 vs. 4). Cotinine levels paralleled self-reported cigarette consumption.

DISCUSSION

Tobacco use is extremely common among inner-city IDUs. Smoking behavior and nicotine dependence did not materially differ by HIV status but were associated with active drug injection. Cessation efforts should target the dual dependence of cigarettes and drugs experienced among this population.

Association of age and comorbidity with physical function in HIV-infected and uninfected patients: results from the Veterans Aging Cohort Study

HIV clinical care now involves prevention and treatment of age-associated comorbidity. Although physical function is an established correlate to comorbidity in older adults without HIV infection, its role in aging of HIV-infected adults is not well understood. To investigate this question we conducted cross-sectional analyses including linear regression models of physical function in 3227 HIV-infected and 3240 uninfected patients enrolled 2002-2006 in the Veterans Aging Cohort Study-8-site (VACS-8). Baseline self-reported physical function correlated with the Short Form-12 physical subscale (ρ = 0.74, p < 0.001), and predicted survival. Across the age groups decline in physical function per year was greater in HIV-infected patients (β(coef) -0.25, p < 0.001) compared to uninfected patients (β(coef) -0.08, p = 0.03). This difference, although statistically significant (p < 0.01), was small. Function in the average 50-year old HIV-infected subject was equivalent to the average 51.5-year-old uninfected subject. History of cardiovascular disease was a significant predictor of poor function, but the effect was similar across groups. Chronic pulmonary disease had a differential effect on function by HIV status (Δβ(coef) -3.5, p = 0.03). A 50-year-old HIV-infected subject with chronic pulmonary disease had the equivalent level of function as a 68.1-year-old uninfected subject with chronic pulmonary disease. We conclude that age-associated comorbidity affects physical function in HIV-infected patients, and may modify the effect of aging. Longitudinal research with markers of disease severity is needed to investigate loss of physical function with aging, and to develop age-specific HIV care guidelines.

Impact of atazanavir-based HAART regimen on the carotid intima-media thickness of HIV-infected persons: a comparative prospective cohort

OBJECTIVE

With the advent of highly active antiretroviral therapy regimens, it is crucial to consider their long-term benefits to risk ratios among HIV-infected persons. The impact of protease inhibitors on the cardiovascular risk is controversial.

DESIGN

This observational cohort was designed to investigate the cardiovascular impact of boosted atazanavir (ATV/r), a protease inhibitor that does not provide major dyslipidemia or insulin resistance.

SETTING

This study was carried out at the University Hospital of Brest (France).

PATIENTS

Among the 229 HIV-infected persons of the cohort, 33 cases treated by ATV/r-containing regimen since less than 6 months were compared to 99 age-matched and sex-matched ATV/r naive controls.

INTERVENTION

None.

MAIN OUTCOME MEASURE

The main outcome measure was carotid intima-media thickness (cIMT) at the baseline, 6, 12, and 18 months.

RESULTS

Although the cIMT was not different at inclusion (0.633 ± 0.05 vs. 0.666 ± 0.09, P = 0.07), the cIMT course significantly decreased (P = 0.018) in cases at 18 months. The differences remained significant even after adjustment on the variables that differed between cases and controls (P < 0.1) at inclusion (high-density lipoprotein cholesterol, cardiovascular family history) and the cumulated and current exposure to the nucleosidic reverse transcriptase inhibitor, nonnucleosidic reverse transcriptase inhibitor, and protease inhibitor class.

CONCLUSION

Despite similar HIV and cardiovascular characteristics at baseline, cIMT decreased after 6 months of follow-up among the patients exposed to ATV/r, even after adjustment for the exposure to the three antiretroviral classes. Considering the shortcomings of this study, especially the absence of randomization and the heterogeneity of the control group, the benefit of ATV/r treatment in patients with high cardiovascular should be confirmed by randomized trials.

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

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

Atherosclerosis: pathogenesis and increased occurrence in individuals with HIV and Mycobacterium tuberculosis infection

Atherosclerosis is a leading cause of coronary heart disease and stroke. Since 1981, more than 980,000 cases of AIDS have been reported in the United States. According to the Centers for Disease Control, more than 1 million Americans may be infected with HIV. By killing or damaging CD4+ T cells of the body’s immune system, HIV progressively destroys the body’s ability to fight infections. People diagnosed with AIDS often suffer from life-threatening diseases caused by opportunistic infections such as tuberculosis. HIV-infected individuals have increased risks for atherosclerosis. This review summarizes the effects of oxidized low density lipoproteins in impairing macrophage functions in individuals with atherosclerosis (with and without HIV infection) thereby enhancing the susceptibility to Mycobacterium tuberculosis infection.

Associations of antiretroviral drug use and HIV-specific risk factors with carotid intima-media thickness

BACKGROUND

Previous research has demonstrated an increase in carotid intima-media thickness (cIMT) in HIV-infected individuals compared to controls. However, the reason for this increased level of subclinical vascular disease is unknown.

OBJECTIVE

To identify HIV-related risk factors for increased cIMT.

METHODS

We evaluated the relationship between HIV-related characteristics (including markers of HIV disease severity and use of antiretroviral therapy) and cIMT measurements in the internal/bulb and common carotid regions among 538 HIV-infected participants from the Study of Fat Redistribution and Metabolic Change in HIV Infection (FRAM). We used Bayesian model averaging to estimate the posterior probability of candidate HIV and non-HIV-related risk factors being true predictors of increased cIMT. Variables with a posterior probability of more than 50% were used to develop a selected regression model for each of the anatomic regions.

RESULTS

For common cIMT, the Bayesian model selection process identified age, African-American race, and systolic and diastolic blood pressure with probability more than 95%, HDL cholesterol with probability 85% and Hispanic ethnicity with probability 51%. Among the HIV-related factors included in the analysis, only tenofovir use was selected (51% probability). In the selected model, duration of tenofovir use was associated with lower common cIMT (-0.0094 mm/year of use; 95% confidence interval: -0.0177 to -0.0010). For internal cIMT, no HIV-related risk factors were above the 50% posterior probability threshold.

CONCLUSION

We observed an inverse association between duration of tenofovir use and common carotid cIMT. Whether this association is causal or due to confounding by indication needs further investigation.

Initiation of antiretroviral therapy at higher nadir CD4+ T-cell counts is associated with reduced arterial stiffness in HIV-infected individuals

OBJECTIVE

HIV infection is associated with increased rates of cardiovascular disease. We sought to evaluate whether initiation of HIV therapy at higher nadir CD4(+) T-cell counts might reduce cardiovascular risk, as measured by arterial stiffness.

DESIGN

We conducted a cross-sectional study of 80 HIV-infected men who were antiretroviral-treated with undetectable plasma HIV RNA levels.

METHODS

Participants underwent noninvasive assessment of arterial stiffness by pulse wave analysis (augmentation index normalized for heart rate of 75 bpm) and carotid-femoral pulse wave velocity, both sensitive measures of cardiovascular risk. A generalized linear model was used to determine the relationship between cardiovascular and HIV-related predictors, and arterial stiffness.

RESULTS

In unadjusted analyses, predictors of arterial stiffness included age, blood pressure, antihypertensive medication use, and nadir CD4(+) T-cell count below 350 cells/microl (all P < 0.05). After adjusting for both cardiovascular risk factors (age, blood pressure, antihypertensive medication use, diabetes, hypercholesterolemia, and smoking) and HIV-related covariates, nadir CD4(+) T-cell count below 350 cells/microl was independently associated with a 0.41 m/s increase in pulse wave velocity (95% confidence interval 0.03-0.79, P = 0.03) and a 7.3% increase in augmentation index (augmentation index normalized for heart rate of 75 bpm; 95% confidence interval 2.6-11.9, P = 0.003). Neither duration of antiretroviral therapy nor exposure to protease inhibitors was associated with arterial stiffness.

CONCLUSION

Among treated HIV-infected individuals, arterial stiffness is independently associated with both traditional cardiovascular risk factors as well as a low nadir CD4(+) T-cell count. Our data suggest that cardiovascular risk among HIV-infected individuals could be reduced through early initiation of antiretroviral therapy, before CD4 T-cell counts are depressed, a concept that should be tested prospectively in future studies.

Traditional risk factors and D-dimer predict incident cardiovascular disease events in chronic HIV infection

OBJECTIVE

Cardiovascular disease (CVD) contributes significantly to HIV-related morbidity and mortality. Chronic immune activation and inflammation are thought to augment the progression of atherosclerotic disease. In this retrospective, case-control study of HIV-infected individuals, we investigated the association of traditional cardiac risk factors, HIV-related disease, and inflammation with CVD events.

METHODS

HIV-infected individuals who experienced an incident CVD event while enrolled in National Institutes of Health clinical protocols from 1995 to 2009 were matched 2: 1 to HIV-infected individuals without known CVD. Markers of inflammation and cell activation were measured in serum or plasma using ELISA-based assays and peripheral mononuclear cells by four-color flow cytometry.

RESULTS

Fifty-two patients experienced an incident CVD event. Events were related to smoking, dyslipidemia, hyperglycemia, and family history as well as elevated D-dimer, soluble vascular cell adhesion molecule-1, tissue inhibitor of metalloproteinase-1, and soluble tissue factor, but not high-sensitivity C-reactive protein. No significant differences in antiviral therapy, CD4 T-cell count, or CD38 and human leukocyte antigen-DR expression were identified between patients and controls. In multivariable analysis, smoking, family history, D-dimer, and glucose were independently related to CVD risk.

CONCLUSION

In this cohort, CVD risk was related to traditional CVD risk factors and markers of thrombosis and endothelial damage, but not to high-sensitivity C-reactive protein or markers of T-cell activation such as CD38/human leukocyte antigen-DR coexpression. D-dimer may help identify HIV-infected patients at elevated CVD risk.

Coronary heart disease risk assessment in HIV-infected patients: a comparison of Framingham, PROCAM and SCORE risk assessment functions

OBJECTIVES

The aim of this was to compare the performance of the Framingham, Systematic Coronary Risk Evaluation (SCORE) and Prospective Cardiovascular Munster (PROCAM) scoring systems in the risk assessment of HIV-infected patients with no overt vascular disease.

METHODS

A cross-sectional study of 220 HIV-infected patients was conducted at the outpatient clinic of a referral and training centre in infectious and parasitic diseases in Belo Horizonte, Brazil. The Framingham, SCORE and PROCAM equations were calculated. Patients were classified as having low, moderate or high risk, which according to the Framingham and PROCAM equations corresponded to < 10%, 10-20% and > 20% respectively, and according to SCORE corresponded to < 3%, 3-4% and > or = 5% respectively. Cohen's kappa coefficient was used to assess agreement between the methods.

RESULTS

Of a total of 220 HIV-infected patients, 56 were antiretroviral (ARV)-naïve while 164 had already been treated with ARV. The prevalence of patients with a high 10-year cardiovascular risk was 3.7%, 2.5% and 1.9% according to the Framingham, PROCAM and SCORE equations respectively. The degree of agreement was moderate between the Framingham and PROCAM risk estimates (kappa = 0.433; p < 0.001), poor-to-fair between the Framingham and SCORE estimates (kappa = 0.220; p < 0.001) and moderate between the PROCAM and SCORE systems (kappa = 0.478; p < 0.001).

CONCLUSIONS

There are differences in risk assessment and in the identification of high risk individuals between the three risk functions under evaluation and only a prospective study will be capable of assessing which offers the best current sensitivity, specificity and predictive values for the population under investigation.

Effect of inter-reader variability on outcomes in studies using carotid intima media thickness quantified by carotid ultrasonography

Systematic differences between readers or equipment in imaging studies are not uncommon; failure to account for such differences when using Carotid Ultrasonography may introduce bias into associations between carotid intima media thickness (cIMT) and outcomes. We demonstrate the impact of this source of systematic measurement error (SME) using data on 5,521 participants from the Multi-Ethnic Study of Atherosclerosis (MESA) and 661 participants from the Study of Fat Redistribution and Metabolic Change in HIV Infection (FRAM). Participants were between 37 and 78 years old. Two outcomes were considered: (1) the effect of HIV infection on cIMT (between study) and (2) the association of cIMT with cardiovascular events (within study). All estimates were adjusted for demographics (age, gender, and ethnicity) and for traditional cardiovascular disease risk factors (smoking, blood pressure, diabetes and cholesterol). When comparing the FRAM and MESA cohorts to estimate the association of HIV infection on common cIMT, accounting for machine and reader variability (between study variability) reduced the difference associated with HIV infection from +0.080 mm (95% Confidence Interval (CI):0.065-0.095) to +0.037 mm (95% CI:0.003 to 0.072) while internal cIMT declined from +0.254 mm (95% CI:0.205-0.303) to +0.192 mm (95% CI:0.076-0.308). Attenuation of the association between cIMT and cardiovascular endpoints occurred when within study reader variability was not accounted for. The effect of SME due to use of multiple readers or machines is most important when comparisons are made between two different study populations. Within-cohort measurement error dilutes the association with events.

Abacavir and cardiovascular risk

PURPOSE OF REVIEW

This review focuses on current studies addressing the association of abacavir (ABC) therapy and myocardial risk in HIV-infected patients, discusses potential pathogenetic mechanisms, and suggests a preliminary algorithm for decision making regarding ABC therapy in daily clinical practise.

RECENT FINDINGS

The D:A:D study was the first to reveal an increased rate of myocardial infarction in patients recently treated with ABC. Subsequent analyses of both cohort studies as well as prospective randomized clinical trials largely confirmed this association. Although these studies varied considerably by design and their ability to control for confounders, they provide early support that ABC therapy can increase the risk for cardiovascular disease. The pathogenesis of this association remains elusive. Preliminary cross-sectional studies suggest the involvement of inflammation associated with ABC.

CONCLUSION

Prospective studies are required to provide additional evidence for the association of ABC therapy and cardiovascular events. In individual patients with underlying high cardiovascular risk, replacement of ABC may be considered, if it can be substituted by alternative equally effective treatment.

A genome-wide association study of carotid atherosclerosis in HIV-infected men

BACKGROUND

The role of host genetics in the development of subclinical atherosclerosis in the context of HIV-infected persons who are being treated with highly active antiretroviral therapy (HAART) is not well understood.

METHODS

The present genome-wide association study (GWAS) is based on 177 HIV-positive Caucasian males receiving HAART who participated in the Fat Redistribution and Metabolic Change in HIV Infection (FRAM) Study. Common and internal carotid intima-media thicknesses (cIMT) measured by B-mode ultrasound were used as a subclinical measure of atherosclerosis. Single nucleotide polymorphisms (SNPs) were assayed using the Illumina HumanCNV370-quad beadchip. Copy Number Variants (CNV) were inferred using a hidden Markov Model (PennCNV). Regression analyses were used to assess the association of common and internal cIMT with individual SNPs and CNVs, adjusting for age, duration of antiretroviral treatment, and principal components to account for potential population stratification.

RESULTS

Two SNPs in tight linkage disequilibrium, rs2229116 (a missense, nonsynonymous polymorphism (IIe to Val)) and rs7177922, located in the ryanodine receptor (RYR3) gene on chromosome 15 were significantly associated with common cIMT (P-value < 1.61 x 10). The RYR gene family has been known to play a role in the etiology of cardiovascular disease and has been shown to be regulated by HIV TAT protein.

CONCLUSION

These results suggest that in the context of HIV infection and HAART, a functional SNP in a biologically plausible candidate gene, RYR3, is associated with increased common carotid IMT, which is a surrogate for atherosclerosis.

Association between kidney function and albuminuria with cardiovascular events in HIV-infected persons

BACKGROUND

Cardiovascular disease (CVD) is now a leading cause of death in HIV-infected persons; however, risk markers for CVD are ill defined in this population. We examined the association between longitudinal measures of kidney function and albuminuria with risk of atherosclerotic CVD and heart failure in a contemporary cohort of HIV-infected individuals.

METHODS AND RESULTS

We followed a national sample of 17 264 HIV-infected persons receiving care in the Veterans Health Administration for (1) incident CVD, defined as coronary, cerebrovascular, or peripheral arterial disease, and (2) incident heart failure. Rates of CVD and heart failure were at least 6-fold greater in the highest-risk patients with an estimated glomerular filtration rate (eGFR) <30 mL/min per 1.73 m(2) and albuminuria > or =300 mg/dL versus those with no evidence of kidney disease (eGFR > or =60 mL/min per 1.73 m(2) and no albuminuria). After multivariable adjustment, eGFR levels 45 to 59, 30 to 44, and <30 mL/min per 1.73 m(2) were associated with hazard ratios for incident CVD of 1.46 (95% confidence interval, 1.15 to 1.86), 2.03 (1.47 to 2.82), and 1.99 (1.46 to 2.70) compared with eGFR > or =60 mL/min per 1.73 m(2). Similarly, albuminuria levels 30, 100, and > or =300 mg/dL had hazard ratios for CVD of 1.28 (1.09 to 1.51), 1.48 (1.15 to 1.90), and 1.71 (1.30 to 2.27) compared with absent albuminuria. The associations between eGFR and albuminuria with heart failure were larger in magnitude and followed the same trends.

CONCLUSIONS

In this national sample of HIV-infected persons, eGFR and albuminuria levels were strongly associated with risk of CVD and heart failure. Kidney function and albuminuria provide complementary prognostic information that may aid CVD risk stratification in HIV-infected persons.

Increased prevalence of subclinical coronary atherosclerosis detected by coronary computed tomography angiography in HIV-infected men

OBJECTIVE

The degree of subclinical coronary atherosclerosis in HIV-infected patients is unknown. We investigated the degree of subclinical atherosclerosis and the relationship of traditional and nontraditional risk factors to early atherosclerotic disease using coronary computed tomography angiography.

DESIGN AND METHODS

Seventy-eight HIV-infected men (age 46.5 +/- 6.5 years and duration of HIV 13.5 +/- 6.1 years, CD4 T lymphocytes 523 +/- 282; 81% undetectable viral load), and 32 HIV-negative men (age 45.4 +/- 7.2 years) with similar demographic and coronary artery disease (CAD) risk factors, without history or symptoms of CAD, were prospectively recruited. 64-slice multidetector row computed tomography coronary angiography was performed to determine prevalence of coronary atherosclerosis, coronary stenosis, and quantitative plaque burden. RESULTS HIV-infected men demonstrated higher prevalence of coronary atherosclerosis than non-HIV-infected men (59 vs. 34%; P = 0.02), higher coronary plaque volume [55.9 (0-207.7); median (IQR) vs. 0 (0-80.5) microl; P = 0.02], greater number of coronary segments with plaque [1 (0-3) vs. 0 (0-1) segments; P = 0.03], and higher prevalence of Agatston calcium score more than 0 (46 vs. 25%, P = 0.04), despite similar Framingham 10-year risk for myocardial infarction, family history of CAD, and smoking status. Among HIV-infected patients, Framingham score, total cholesterol, low-density lipoprotein, CD4/CD8 ratio, and monocyte chemoattractant protein 1 were significantly associated with plaque burden. Duration of HIV infection was significantly associated with plaque volume (P = 0.002) and segments with plaque (P = 0.0009) and these relationships remained significant after adjustment for age, traditional risk factors, or duration of antiretroviral therapy. A total of 6.5% (95% confidence interval 2-15%) of our study population demonstrated angiographic evidence of obstructive CAD (>70% luminal narrowing) as compared with 0% in controls.

CONCLUSION

Young, asymptomatic, HIV-infected men with long-standing HIV disease demonstrate an increased prevalence and degree of coronary atherosclerosis compared with non-HIV-infected patients. Both traditional and nontraditional risk factors contribute to atherosclerotic disease in HIV-infected patients.

The macrophage: the intersection between HIV infection and atherosclerosis

HIV-infected individuals are at increased risk of coronary artery disease (CAD) with underlying mechanisms including chronic immune activation and inflammation secondary to HIV-induced microbial translocation and low-grade endotoxemia; direct effects of HIV and viral proteins on macrophage cholesterol metabolism; and dyslipidemia related to HIV infection and specific antiretroviral therapies. Monocytes are the precursors of the lipid-laden foam cells within the atherosclerotic plaque and produce high levels of proinflammatory cytokines such as IL-6. The minor CD14+/CD16+ "proinflammatory" monocyte subpopulation is preferentially susceptible to HIV infection and may play a critical role in the pathogenesis of HIV-related CAD. In this review, the central role of monocytes/macrophages in HIV-related CAD and the importance of inflammation and cholesterol metabolism are discussed.

Women and HIV infection: the makings of a midlife crisis

With the advent of highly active antiretroviral agents, women with HIV infection can expect to live longer than ever before. This increased survival has led to concerns about the long-term implications of HIV disease and its treatment. Women with HIV infection appear to lose ovarian function earlier in life than women without HIV infection. They also have evidence of reduced bone mineral density and increased cardiovascular risk. Moreover, many of these increases in risk factors are present even prior to the menopausal transition. All of these risks, present at midlife, augur poorly for future health and describe a substantially increased burden of disease likely to accrue to HIV-infected women as they enter older age groups. Further compounding the adversity faced by the HIV infected, the demographics of women most vulnerable to this disease include adverse social and economic influences, both of which worsen their long-term prognosis. For example, drug use and poverty are related to more severe menopausal symptoms and chronic stress is related to worse psychological and cardiovascular risk. An understanding of how menopause interacts with HIV infection is therefore most important to alert the clinician to perform surveillance for common health problems in postmenopausal women, and to address directly and appropriately symptomatology during the menopausal transition.