Factors associated with accelerated atherosclerosis in HIV-1-infected persons treated with protease inhibitors

Circulating levels of cardiac troponin T are associated with coronary noncalcified plaque burden in HIV-infected adults: a pilot study

HIV infection and/or antiretroviral therapy may increase the risk of subclinical coronary atherosclerosis. However, patients with chronic kidney disease (CKD) and those without IV access cannot undergo contrast-enhanced coronary CT angiography (CCTA). This study was to explore the relationship between cardiac troponin T (cTnT) levels and the extent of coronary plaque burden, as assessed by CCTA in those with HIV infection. Between June and September 2017, 58 HIV-infected participants were recruited and underwent contrast-enhanced CCTA. cTnT was measured with the Elecsys Troponin T Gen 5 STAT assay, and noncalcified plaque burden was quantified using coronary plaque analysis. Robust regression model was employed to perform primary statistical analysis. Univariate robust regression analysis indicated that male gender, cardiovascular risk score defined by the 2013 ACC/AHA cardiovascular risk score algorithm, and cTnT levels were significantly associated with noncalcified plaque volume index (NCPI). Final robust regression analyses showed that only cTnT (log scale) was independently associated with the NCPI (regression coefficient: 0.0453 with 95% CI: 0.0151, 0.0755, p = 0.003). These results of this study suggest that cTnT may be a promising marker for coronary plaque burden, especially in patients with HIV-associated CKD or without IV access.

HIV Infection Itself May Not Be Associated With Subclinical Coronary Artery Disease Among African Americans Without Cardiovascular Symptoms

Background

The key objectives of this study were to examine whether HIV infection itself is associated with subclinical coronary atherosclerosis and the potential contributions of cocaine use and antiretroviral therapies (ARTs) to subclinical coronary artery disease (CAD) in HIV‐infected persons.

Methods and Results

Between June 2004 and February 2015, 1429 African American (AA) adults with/without HIV infection in Baltimore, Maryland, were enrolled in an observational study of the effects of HIV infection, exposure to ART, and cocaine use on subclinical CAD. The prevalence of subclinical coronary atherosclerosis was 30.0% in HIV‐uninfected and 33.7% in HIV‐infected (P=0.17). Stratified analyses revealed that compared to HIV‐uninfected, HIV‐infected ART naïve were at significantly lower risk for subclinical coronary atherosclerosis, whereas HIV‐infected long‐term ART users (≥36 months) were at significantly higher risk. Thus, an overall nonsignificant association between subclinical coronary atherosclerosis and HIV was found. Furthermore, compared to those who were ART naïve, long‐term ART users (≥36 months) were at significantly higher risk for subclinical coronary atherosclerosis in chronic cocaine users, but not in those who never used cocaine. Cocaine use was independently associated with subclinical coronary atherosclerosis.

Conclusions

Overall, HIV infection, per se, was not associated with subclinical coronary atherosclerosis in this population. Cocaine use was prevalent in both HIV‐infected and ‐uninfected individuals and itself was associated with subclinical disease. In addition, cocaine significantly elevated the risk for ART‐associated subclinical coronary atherosclerosis. Treating cocaine addiction must be a high priority for managing HIV disease and preventing HIV/ART‐associated subclinical and clinical CAD in individuals with HIV infection.

Anemia and Red Blood Cell Indices Predict HIV-Associated Neurocognitive Impairment in the Highly Active Antiretroviral Therapy Era

BACKGROUND

Anemia has been linked to adverse human immunodeficiency virus (HIV) outcomes, including dementia, in the era before highly active antiretroviral therapy (HAART). Milder forms of HIV-associated neurocognitive disorder (HAND) remain common in HIV-infected persons, despite HAART, but whether anemia predicts HAND in the HAART era is unknown.

METHODS

We evaluated time-dependent associations of anemia and cross-sectional associations of red blood cell indices with neurocognitive impairment in a multicenter, HAART-era HIV cohort study (N = 1261), adjusting for potential confounders, including age, nadir CD4(+) T-cell count, zidovudine use, and comorbid conditions. Subjects underwent comprehensive neuropsychiatric and neuromedical assessments.

RESULTS

HAND, defined according to standardized criteria, occurred in 595 subjects (47%) at entry. Mean corpuscular volume and mean corpuscular hemoglobin were positively associated with the global deficit score, a continuous measure of neurocognitive impairment (both P < .01), as well as with all HAND, milder forms of HAND, and HIV-associated dementia in multivariable analyses (all P < .05). Anemia independently predicted development of HAND during a median follow-up of 72 months (adjusted hazard ratio, 1.55; P < .01).

CONCLUSIONS

Anemia and red blood cell indices predict HAND in the HAART era and may contribute to risk assessment. Future studies should address whether treating anemia may help to prevent HAND or improve cognitive function in HIV-infected persons.

Vitamin D deficiency is associated with coronary artery calcification in cardiovascularly asymptomatic African Americans with HIV infection

OBJECTIVE

Patients with HIV infection are at increased risk for coronary artery disease (CAD), and growing evidence suggests a possible link between vitamin D deficiency and clinical/subclinical CAD. However, the relationship between vitamin D deficiency and coronary artery calcification (CAC), a sensitive marker for subclinical CAD, in those with HIV infection is not well investigated.

METHODS

CAC was quantified using a Siemens Cardiac 64 scanner, and vitamin D levels and the presence of traditional and novel risk factors for CAD were obtained in 846 HIV-infected African American (AA) participants aged 25 years or older in Baltimore, MD, USA without symptoms or clinical evidence of CAD.

RESULTS

The prevalence of vitamin D deficiency (25-hydroxy vitamin D <10 ng/mL) was 18.7%. CAC was present in 238 (28.1%) of the 846 participants. Logistic regression analysis revealed that the following factors were independently associated with CAC: age (adjusted odds ratio [OR]: 1.11; 95% confidence interval [CI]: 1.08-1.14); male sex (adjusted OR: 1.71; 95% CI: 1.18-2.49); family history of CAD (adjusted OR: 1.53; 95% CI: 1.05-2.23); total cholesterol (adjusted OR: 1.006; 95% CI: 1.002-1.010); high-density lipoprotein cholesterol (adjusted OR: 0.989; 95% CI: 0.979-0.999); years of cocaine use (adjusted OR: 1.02; 95% CI: 1.001-1.04); duration of exposure to protease inhibitors (adjusted OR: 1.004; 95% CI: 1.001-1.007); and vitamin D deficiency (adjusted OR: 1.98; 95% CI: 1.31-3.00).

CONCLUSION

Both vitamin D deficiency and CAC are prevalent in AAs with HIV infection. In order to reduce the risk for CAD in HIV-infected AAs, vitamin D levels should be closely monitored. These data also suggest that clinical trials should be conducted to examine whether vitamin D supplementations reduce the risk of CAD in this AA population.

Incident hypertension in older women and men with or at risk for HIV infection

OBJECTIVES

Antiretroviral (ARV) therapy has prolonged the life expectancy of HIV-infected persons, increasing their risk of age-associated diseases, including atherosclerosis (AS). Decreased risk of AS has been associated with the prevention and control of hypertension (HTN). We conducted a cohort study of perimenopausal women and older men with or at risk of HIV infection to identify risk factors for incident HTN.

METHODS

Standardized interviews, physical examinations, and laboratory examinations were scheduled at 6-month intervals. Interview data included demographics, medical, family, sexual behaviour and drug use histories, and physical activity.

RESULTS

There were 330 women and 329 men eligible for inclusion in the study; 27% and 35% of participants developed HTN during a median follow-up period of 1080 and 1071 days, respectively. In gender-stratified analysis, adjusting for traditional HTN risk factors (age, race, body mass index, smoking, diabetes, family history of HTN, alcohol dependence, physical activity and high cholesterol), HIV infection was not associated with incident HTN in women [hazard ratio (HR) 1.31; 95% confidence interval (CI) 0.56, 3.06] or men (HR 1.67; 95% CI 0.75, 3.74). Among HIV-infected women, although exposure to ARVs was not significantly associated with incident HTN (HR 0.72; 95% CI 0.26, 1.99), CD4 T-cell count was positively associated with incident HTN (HR 1.15 per 100 cells/μL; 95% CI 1.03, 1.28). Among physically active HIV-infected men, exposure to ARVs was negatively associated with incident HTN (HR 0.15; 95% CI 0.03, 0.78).

CONCLUSIONS

HIV infection was not associated with incident HTN in older men or women. This study provides additional evidence supporting a causal relationship between immune function and incident HTN, which warrants further study.

Vitamin D deficiency is associated with silent coronary artery disease in cardiovascularly asymptomatic African Americans with HIV infection

BACKGROUND

Growing evidence suggests that vitamin D deficiency Is associated with clinical coronary artery disease (CAD). The relationship between vitamin D deficiency and subclinical CAD in HIV-infected individuals is not well-characterized.

METHODS

Computed tomographic (CT) coronary angiography was performed using contrast-enhanced 64-slice multidetector CT imaging, and vitamin D levels and the presence of traditional and novel risk factor for CAD were obtained in 674 HIV-infected African American (AA) participants aged 25-54 years in Baltimore, MD, without symptoms/clinical evidence of CAD.

RESULTS

The prevalence of vitamin D deficiency (25-hydroxy vitamin D <10 ng/mL) was 20.0% (95% confidence interval [CI], 16.9-23.1). Significant (≥50%) coronary stenosis was present in 64 (9.5%) of 674 participants. Multiple logistic regression analysis revealed that male gender (adjusted odds ratio [OR], 2.19; 95% CI, 1.17-4.10), diastolic BP ≥85 mmHg (adjusted OR: 1.94, 95% CI: 1.02 -3.68), low-density lipoprotein cholesterol ≥100 mg/dL (adjusted OR, 1.95; 95% CI, 1.13-3.36), cocaine use for ≥15 years (adjusted OR, 1.77; 95% CI, 1.01-3.10), use of antiretroviral therapies for ≥6 months (adjusted OR, 2.26; 95% CI, 1.17-4.36), year of enrollment after 2005 (adjusted ORs for 2006-2007, 2008-2009, and 2010 were 0.32 [95% CI, 0.13-0.76], 0.26 [95% CI, 0.12-0.56], and 0.32 (95% CI, 0.15-0.65], respectively), and vitamin D deficiency (adjusted OR, 2.28; 95% CI, 1.23-4.21) were independently associated with significant coronary stenosis.

CONCLUSIONS

Both vitamin D deficiency and silent CAD are prevalent in HIV-infected AAs. In addition to management of traditional CAD risk factors and substance abuse, vitamin D deficiency should be evaluated in HIV-infected AAs. These data support the conduct of a prospective trial of vitamin D in this high-risk patient population.

HIV infection and progression of carotid and coronary atherosclerosis: the CARE study

BACKGROUND

Progression of carotid intima-media thickness (c-IMT) and coronary artery calcium (CAC) are increasingly used as surrogates for vascular risk. We assessed the predictors of c-IMT and CAC progression in a large longitudinal cohort of HIV-infected adults.

METHODS

c-IMT, CAC scores, and vascular and HIV risk factors were evaluated at baseline and at 3-year follow-up in 255 HIV-infected adults. Multivariate regression was used to determine the predictors of atherosclerotic progression.

RESULTS

The mean change in c-IMT per year of follow-up was 0.016 mm for the common and 0.020 mm for the internal. Significant predictors of yearly progression were age, systolic blood pressure, triglycerides, and insulin for common c-IMT and triglycerides >=150 mg/dL, glucose >126 mg/dL, use of glucose-lowering medications, quantitative insulin sensitivity check index, high waist circumference, and current smoking for internal c-IMT. Twenty-eight percent had CAC progression. Of those with zero CAC at baseline, 32% had detectable scores at follow-up. Of those with detectable CAC at baseline, 26% had progression at follow-up. For CAC score, quantitative insulin sensitivity check index, apolipoprotein B, and triglycerides predicted progression. Those with abnormal surrogate markers at baseline were more likely to have the metabolic syndrome reversed and be started on antihypertensive medications over the 3-year follow-up period than those who had no abnormalities at baseline.

CONCLUSIONS

Although c-IMT and CAC progression rates in HIV-infected patients appear higher than expected for this age and risk groups, traditional cardiovascular risk factors remain the strongest determinants of carotid and coronary atherosclerotic disease progression in HIV-infected patients. Aggressive cardiovascular risk reduction is effective at slowing the atherosclerotic progression in those with preexisting disease.

Endothelial, inflammatory, coagulation, metabolic effects and safety of etravirine in HIV-uninfected volunteers

The innate proatherosclerotic properties of non-nucleoside reverse transcriptase inhibitors have not previously been examined. Therefore, we performed a pilot study of etravirine (ETR) in healthy volunteers over 28 days. This investigation also allowed us to evaluate the safety of ETR over a period commonly used for HIV postexposure prophylaxis. ETR 200 mg twice daily was given to 28 healthy HIV-uninfected volunteers over 28 days. Flow-mediated dilation (FMD) of the brachial artery and circulating markers of inflammation, coagulation, and metabolism were measured at entry and at day 28. These circulating markers were also measured at day 35. Of the initial 28 subjects, 23 completed both entry and day 28 procedures. Two subjects were discontinued due to development of rash. No other major toxicities developed. The change in FMD over 28 days was minimal and not significant (0.03 [-3.21, 0.97] %; p=0.36). The post hoc estimated detectable absolute change in FMD with the 23 subjects in our study was 2.26%, which is an effect size that has been associated with future cardiovascular event rates in the general population; thus our study had sufficient power to find clinically relevant changes in FMD. In addition, there were no significant changes in any of the circulating markers from entry to day 28 or from day 28 to day 35. ETR did not demonstrate any innate proatherosclerotic properties over 28 days in these HIV-uninfected volunteers. ETR was generally well tolerated. Larger studies are warranted to confirm that ETR can be used safely as part of HIV postexposure prophylaxis regimens.

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.

Identifying individuals with virologic failure after initiating effective antiretroviral therapy: The surprising value of mean corpuscular hemoglobin in a cross-sectional study

Objective

Recent studies have shown that the current guidelines suggesting immunologic monitoring to determine response to highly active antiretroviral therapy (HAART) are inadequate. We assessed whether routinely collected clinical markers could improve prediction of concurrent HIV RNA levels.

Methods

We included individuals followed within the Johns Hopkins HIV Clinical Cohort who initiated antiretroviral therapy and had concurrent HIV RNA and biomarker measurements ≥4 months after HAART. A two tiered approach to determine whether clinical markers could improve prediction included: 1) identification of predictors of HIV RNA levels >500 copies/ml and 2) construction and validation of a prediction model.

Results

Three markers (mean corpuscular hemoglobin [MCH], CD4, and change in percent CD4 from pre-HAART levels) in addition to the change in MCH from pre-HAART levels contained the most predictive information for identifying an HIV RNA >500 copies/ml. However, MCH and change in MCH were the two most predictive followed by CD4 and change in percent CD4. The logistic prediction model in the validation data had an area under the receiver operating characteristic curve of 0.85, and a sensitivity and specificity of 0.74 (95% CI: 0.69-0.79) and 0.89 (95% CI: 0.86-0.91), respectively.

Conclusions

Immunologic criteria have been shown to be a poor guideline for identifying individuals with high HIV RNA levels. MCH and change in MCH were the strongest predictors of HIV RNA levels >500. When combined with CD4 and percent CD4 as covariates in a model, a high level of discrimination between those with and without HIV RNA levels >500 was obtained. These data suggest an unexplored relationship between HIV RNA and MCH.

Immunomodulation in female B₆C₃F₁ mice following treatment with the HIV protease inhibitor saquinavir for 28 days by gavage

Saquinavir (SQV) is a protease inhibitor that binds to the protease active site of the human immunodeficiency virus and prevents the cleavage of viral polyproteins resulting in the formation of non-infectious virus particles. The purpose of these studies was to determine the potential effects of SQV on the immune system in female B₆C₃F₁ mice. SQV was administered by gavage twice daily for 28 days at total doses of 300, 600, and 1200 mg/kg/day. No significant differences were observed in body weight, or the weights of spleen, thymus, liver, kidneys, or lungs. Exposure to SQV produced no biologically meaningful changes in hematological parameters. However, a statistically significant increase in the number of T-cells (23%) was observed at the high dose level of SQV. The number of splenic immature T-cells (CD4+CD8+ cells) also showed increases of 46% and 92% at the 600 and 1200 mg/kg dose levels, respectively. The immunoglobulin M antibody-forming cell (AFC) response was significantly increased by 41% when the data were expressed as AFC/10⁶ spleen cells at the 1200 mg/kg dose level. Treatment with SQV had no effects on the mixed leukocyte response. Overall, the activities of natural killer cells and cytotoxic T-cells were not altered in SQV-treated animals when compared to vehicle controls. In addition, exposure to SQV did not affect host resistance in the B16F10 melanoma model. In conclusion, SQV produced an enhancement of the humoral immune response, possibly through modulating T-cell function in female B₆C₃F₁ mice.

Cardiovascular complications in HIV-infected individuals

PURPOSE OF REVIEW

This review updates the relationship between HIV and cardiovascular abnormalities in the context of the pathophysiology of coronary artery disease.

RECENT FINDINGS

The evaluation of cardiovascular risk in patients with HIV hinges upon a complex interplay of direct and indirect vascular effects of HIV infection, antiretroviral therapy, aging, and exposure to cardiovascular risk factors. Carotid artery intima-media thickness and endothelial-dependent flow-mediated vasodilatation of the brachial artery, which gives an indication of the structural and functional aspect of the endothelium as well as soluble biomarkers, can help to assess the potential harm and benefits of antiretroviral drugs and address the residual burden of cardiovascular risk in the HIV population.

SUMMARY

Given the complex pathophysiology of cardiovascular disease, no single biomarker is likely to be able to provide a universal surrogate whereby change observed independently predicts benefit, increased risk, or no effect across all drugs and mechanistic targets. Investigations and treatments must be tailored in the single patient according to non-modifiable and modifiable risk factors, including exposure to highly active antiretroviral therapy. With proper risk stratification altering the approach to highly active antiretroviral therapy, lifestyle changes, and lipid-lowering medications are the basis for reducing cardiovascular risk in HIV-infected patients.

Subclinical coronary atherosclerosis, HIV infection and antiretroviral therapy: Multicenter AIDS Cohort Study

OBJECTIVE

To evaluate the association of HIV infection and cumulative exposure to highly active antiretroviral therapy (HAART) with the presence and extent of coronary artery calcification (CAC).

DESIGN

A cross-sectional study of 947 male participants (332 HIV-seronegative, 84 HAART-naive and 531 HAART-experienced HIV-infected) from the Multicenter AIDS Cohort Study.

METHODS

The main outcome was CAC score calculated as the geometric mean of the Agatston scores of two computed tomography replicates. Presence of CAC was defined as calcification score above 10, and extent of CAC by the score for those with CAC present. Multivariable regression was used to evaluate the association between HIV infection and HAART and presence and extent of calcification.

RESULTS

Increasing age was most strongly associated with both prevalence and extent of CAC for all study groups. After adjustment for age, race, family history, smoking, high-density lipoprotein-C, low-density lipoprotein-C and hypertension, HIV infection (odds ratio, 1.35; 95% confidence interval, 0.70, 2.61) and long-term HAART use (odds ratio, 1.33; 95% confidence interval, 0.87, 2.05) increased the odds for presence of CAC. In contrast, after adjustment for these covariates, the extent of CAC was lower among HAART users. Among those not taking lipid-lowering therapy, HAART usage of at least 8 years was associated with significantly reduced CAC scores (relative CAC score, 0.43; 95% confidence interval, 0.24, 0.79).

CONCLUSION

HAART use may have different effects on the presence and extent of coronary calcification. Although prevalence of calcification was marginally increased among long-term HAART users, the extent of calcification was significantly reduced among HAART users compared with HIV-seronegative controls.

Coronary atherosclerotic lesions in human immunodeficiency virus-infected patients: a histopathologic study

BACKGROUND

Studies suggest human immunodeficiency virus-positive (HIV+) patients have an increased risk of coronary artery disease (CAD), yet little is known about the histopathology, severity, or distribution of lesions.

METHODS

The coronary arteries of 66 deceased AIDS patients and 19 HIV controls (age <55) were dissected and graded for percent luminal stenosis by intimal lesions, percent of intima involved with lipid, and extent of intimal calcification on a scale of 0 to 3. Medical histories, antiretroviral therapies, and CAD risk factors were reviewed.

RESULTS

HIV+ patients were older than controls (P=.06), and more were male (P=.02). Thirty-five percent of HIV+ patients had stenosis >or=75% of at least one artery. Compared to controls, HIV+ patients had three times greater odds of stenosis >or=75%, controlling for age and sex (one-sided P=.03). Older age and male sex were also risk factors (one-sided P<.001). HIV seropositivity was associated with increased plaque lipid content (one-sided P=.02) and calcification (one-sided P=.08). Duration of HIV infection, antiretroviral therapy, and immune status did not predict severe disease in multivariate analyses. Previously unreported patterns of dystrophic calcification were observed in HIV+ patients and older controls.

CONCLUSIONS

Young to middle-aged patients dying from advanced AIDS have atherosclerotic CAD that may result in luminal narrowing, heavy calcification, and high plaque lipid content. The pattern of disease, location of lesions, and plaque composition are typical of atherosclerosis in HIV-negative patients. No relationship between antiretroviral therapies and atherosclerosis was seen in this small study of heavily treated patients.

The role of C-reactive protein as a marker for cardiovascular risk associated with antiretroviral therapy in HIV-infected patients

C-reactive protein (CRP) has been associated with prognosis of HIV-infection, but its relationship with cardiovascular disease remains unknown. We aimed to evaluate whether CRP may be a marker of cardiovascular risk in HIV-infected patients, and to determine the influence of antiretroviral therapy (ART) on CRP levels. We conducted a cross-sectional study on 245 consecutive HIV-infected patients during a 2-month period. An extensive workup for cardiovascular risk was performed, including determination of CRP levels measured by an ultrasensitive immunoturbidimetric assay (detection limit, 0.003 mg/dl). Ninety-nine (40.4%) patients had serum CRP concentrations above 0.3 mg/dl, considered to represent individuals at high risk for developing cardiovascular complications. In univariate analysis, CRP levels correlated positively with total cholesterol (p=0.01), LDL cholesterol (p=0.001), triglycerides (p=0.04) and Framingham risk score (p=0.006), and negatively with HDL cholesterol (p=0.004). Concentrations of CRP were higher in males (p=0.05) and smokers (p=0.002). No correlation was found between CRP levels and HIV-viral load or CD4 cell counts. In multivariate analysis, independent factors associated with the highest quartile of serum CRP concentrations (0.49 mg/dl) were LDL-cholesterol (p<0.001), HDL-cholesterol (p=0.001), cigarette smoking (p=0.019) and current ART (p=0.021). Our results show that C-reactive protein is associated with traditional cardiovascular risk factors, and may then be a marker for cardiovascular risk linked to HIV infection and ART.

Metabolic syndrome and subclinical atherosclerosis in patients infected with HIV

BACKGROUND

The present study examines the association between carotid and coronary atherosclerosis and metabolic syndrome in human immunodeficiency virus (HIV)-infected adults.

METHODS

We measured the common and internal carotid intima-media thickness (c-IMT) using B-mode ultrasonography, and we measured coronary artery calcium (CAC) using high-resolution, electrocardiographic, synchronized, computed tomography, for 314 HIV-infected men and women. Metabolic syndrome was defined by National Cholesterol Education Program/Adult Treatment Panel III criteria. We compared the c-IMT measurements and CAC scores of patients with metabolic syndrome with the scores of those without metabolic syndrome using a Wilcoxon test for continuous variables and a chi2 test for categorical variables. To examine the association between surrogate markers and metabolic syndrome, we used logistic regression analysis.

RESULTS

Participants with metabolic syndrome were more likely to have a common c-IMT measurement >0.8 mm than were those without metabolic syndrome (17% vs.7%; P=.009), but both groups were equally likely to have an internal c-IMT measurement >1.0 mm (20% vs. 13%; P=.15). Any positive CAC score was more likely to occur for participants with metabolic syndrome (80.3% vs. 46.7%; P<.0001). In a multivariate model adjusted for sex, age, ethnicity, and smoking status, participants with metabolic syndrome were more likely than those without metabolic syndrome to have an abnormal common c-IMT measurement (odds ratio [OR], 2.9; P=.020) and detectable CAC scores (OR, 4.9; P<.0001) but not a higher internal c-IMT measurement (OR, 1.6; P=.255).

CONCLUSION

Our study demonstrates that HIV-infected individuals with metabolic syndrome may be at increased risk for subclinical atherosclerosis and supports screening for metabolic syndrome among HIV-infected patients at risk for cardiovascular disease.

HIV protease inhibitors modulate apoptosis signaling in vitro and in vivo

HIV protease inhibitors are an integral part of effective anti-HIV therapy. The drugs block HIV protease, prevent proper packaging of HIV virions, and decrease the HIV viral burden in the peripheral blood of infected individuals. In addition to direct anti-viral effects, the HIV protease inhibitors also modulate apoptosis. A growing body of work demonstrates the anti-apoptotic effects of HIV protease inhibitors on CD4+ and CD8+ T cells during HIV infection. The mechanism of this apoptosis inhibition is supported by several proposed hypotheses for how they alter the fate of the cell, including preventing adenine nucleotide translocator pore function, which consequently prevents loss of mitochondrial transmembrane potential. More recently, the anti-apoptotic effects of the HIV protease inhibitors have been tested in non-HIV, non-immune cell, whereby protease inhibitors prevent apoptosis, and disease in animal models of sepsis, hepatitis, pancreatitis and stroke. Interestingly, when HIV protease inhibitors are used at supra-therapeutic concentrations, they exert pro-apoptotic effects. This has been demonstrated in a number of tumor models. Although it is unclear how HIV protease inhibitors can induce apoptosis at increased concentrations, future research will define the targets of the immunomodulation and reveal the full clinical potential of this intriguing class of drugs.

Risk of cardiovascular disease in a cohort of HIV-infected adults: a study using carotid intima-media thickness and coronary artery calcium score

BACKGROUND

There is concern that human immunodeficiency virus (HIV) infection and the use of highly active antiretroviral therapy lead to accelerated atherosclerosis and increased risk of cardiovascular disease. We measured 2 surrogate markers of subclinical atherosclerosis, carotid intima-media thickness (c-IMT) and coronary artery calcium (CAC) scores, in HIV-infected adults.

METHODS

A cross-sectional analysis of 242 men and 85 women with HIV infection was used. Carotid ultrasonography and coronary computed tomography were performed, and their associations with cardiovascular risk factors were examined.

RESULTS

Among men, the mean (+/- standard deviation [SD]) common c-IMT was 0.62+/-0.2 mm, the mean (+/-SD) internal c-IMT was 0.76+/-0.5 mm, and 136 patients (56.1%) had detectable CAC. Among women, the mean (+/-SD) common c-IMT was 0.59+/-0.2 mm, the mean (+/-SD) internal c-IMT was 0.66+/-0.4 mm, and 40 patients (47.1%) had detectable CAC. Neither the c-IMT nor the CAC score differed by antiretroviral therapy class or individual medications for either sex. For men, age and waist circumference independently predicted common c-IMT; age, systolic blood pressure, and high-sensitivity C-reactive protein level independently predicted internal c-IMT; and age, apolipoprotein B level, and high-sensitivity C-reactive protein level independently predicted CAC score. For women, age and body mass index independently predicted common c-IMT; age independently predicted internal c-IMT; and age and glucose level independently predicted CAC score.

CONCLUSIONS

Our participants had more abnormal surrogate markers than expected at a relatively young age, but those were not associated with use of highly active antiretroviral therapy or protease inhibitors. At present, the positive associations were primarily with traditional and novel cardiovascular risk factors. Some HIV-specific (not treatment-specific) factors were observed; they may become more evident with prolonged HIV infection and treatment.

A prospective, 96-week study of the impact of Trizivir, Combivir/nelfinavir, and lamivudine/stavudine/nelfinavir on lipids, metabolic parameters and efficacy in antiretroviral-naive patients: effect of sex and ethnicity

OBJECTIVES

To compare the lipid and metabolic effects, efficacy, and safety of twice-daily regimens of Trizivir (abacavir 300 mg/lamivudine 150 mg/zidovudine 300 mg triple nucleoside tablet; TZV), Combivir (lamivudine 150 mg/zidovudine 300 mg combination tablet; COM)+nelfinavir (NFV), and stavudine (d4 T)+lamivudine (3TC)+NFV.

STUDY DESIGN

An international, phase 4, open-label, parallel-group, 34-centre study was conducted in 254 non-diabetic, antiretroviral-naive, HIV-infected out-patients with an HIV-1 RNA level of >1000 HIV-1 RNA copies/mL and < or =200,000 copies/mL and a CD4 cell count of >50 cells/microL.

METHODS

Patients were randomized 1 : 1 : 1 to TZV twice daily (n = 85), COM/NFV 1250 mg twice daily (n = 88), or d4T 40 mg+3TC 150 mg+NFV 1250 mg twice daily (n = 81) for 96 weeks. Treatments were compared using analysis of covariance (ANCOVA) with regard to changes from baseline in fasting lipids in the total population and in sex and ethnic subgroups. The proportions of patients achieving HIV-1 RNA <50 and <400 copies/mL were compared using a 95% confidence interval (CI) on the difference between proportions.

RESULTS

The study population was diverse (50% female, 40% black and 37% Hispanic). Mean baseline low-density lipoprotein (LDL) cholesterol was 99 mg/dL, HIV-1 RNA was 4.43 log10 copies/mL and CD4 cell count was 355 cells/microL. At week 96, fasting LDL cholesterol changed minimally in the TZV group [least square mean (LSM) change from baseline, -8 mg/dL], but increased with d4T/3TC/NFV and COM/NFV (+29 and +19 mg/dL, respectively; P < 0.001 versus TZV). Week 96 LDL-cholesterol levels were significantly lower in the TZV group than in the other two treatment groups in women and men and lower than in the d4T/3TC/NFV group in Hispanic and black patients. In black patients, the week-96 LSM change from baseline in LDL cholesterol was significantly less with TZV than with d4T/3TC/NFV (+1 vs+39 mg/dL; P = 0.003). Total cholesterol >200 mg/dL occurred in a smaller proportion of patients receiving TZV (30%) compared with COM/NFV (50%) or d4T/3TC/NFV (60%; P = 0.005 vs TZV). High-density lipoprotein (HDL) cholesterol did not change markedly with any treatment. Although triglycerides increased, they changed least in women and Hispanic patients receiving TZV. Virological and CD4 responses to the treatments were similar in the total population and in the subgroups. Diarrhoea was reported more often in the NFV arms and nausea in the ZDV arms.

CONCLUSIONS

Over 96 weeks, TZV twice daily has significantly less effect on LDL cholesterol than COM/NFV or d4T/3TC/NFV twice daily, especially in women and black patients, and is associated with similar virological and CD4 responses.

Scutellaria baicalensis decreases ritonavir-induced nausea

Background

Protease inhibitors, particularly ritonavir, causes significant gastrointestinal disturbances such as nausea, even at low doses. This ritonavir-induced nausea could be related to its oxidative stress in the gut. Alleviation of drug-induced nausea is important in effectively increasing patients' compliance and improving their quality of life. Conventional anti-emetic drugs can only partially abate the symptoms in these patients, and their cost has also been a concern. Rats respond to nausea-producing emetic stimuli by increasing consumption of non-nutritive substances like kaolin or clay, a phenomenon known as pica. In this study, we used this rat pica model to evaluate the effects of Scutellaria baicalensis, a commonly used oriental herbal medicine, on ritonavir-induced nausea.

Results

Rats treated with 20 mg/kg ritonavir significant caused increases of kaolin consumption at 24 to 48 hr (P < 0.01). Pretreatment with 0.3 and 3 mg/kg Scutellaria baicalensis extract significantly decreased ritonavir-induced kaolin intake in a dose-related manner (P < 0.01). Compared to vehicle treatment, the extract completely prevented ritonavir-induced kaolin consumption at dose 3 mg/kg. The area under the curves (AUC) for kaolin intake from time 0 to 120 hr for vehicle only, ritonavir only, SbE 0.3 mg/kg plus ritonavir, and SbE 3 mg/kg plus ritonavir were 27.3 g•hr, 146.7 g•hr, 123.2 g•hr, and 32.7 g•hr, respectively. The reduction in area under the curves of kaolin intake from time 0 to 120 hr between ritonavir only and SbE 0.3 mg/kg plus ritonavir, ritonavir only and SbE 3 mg/kg plus ritonavir were 16.0% and 77.7%, respectively.

Conclusion

Scutellaria baicalensis significantly attenuated ritonavir-induced pica, and demonstrated a potential in treating ritonavir-induced nausea.

Premature atherosclerosis in HIV positive patients and cumulated time of exposure to antiretroviral therapy (SHIVA study)

BACKGROUND

With the advent of antiretroviral therapy regimens in HIV positive patients, it is crucial to consider their long-term benefits to risk ratios. The responsibility of treatment in premature atherosclerosis is not clear. Thus, the aim of this study is to evaluate the impact of exposure to reverse transcriptase inhibitors (nucleosidic and non-nucleosidic) and to protease inhibitors on the cardiovascular status of an entire hospital based cohort of patients.

METHODS

154 patients were included. Using a linear analysis, we sought an association between the cumulative time of exposure to these three classes of antiretroviral drugs and the carotid intima-media thickness measured by ultrasonography and a cardiovascular composite score.

RESULTS

The study confirms premature atherosclerosis, which not only correlates with the usual risk factors, such as triglyceride level, but also with protease inhibitor exposure, especially that of lopinavir. Nevertheless as regards current drug exposure, the clinical impact was low: five clinical complications of atherosclerosis and only one out of 35 scintigraphic and ECG exercise tests warranted a coronary angiography which was negative.

CONCLUSION

These data should not lead to the rejection of protease inhibitors but should strengthen the prevention of cardiovascular diseases as an integral part of the management of HIV patients.

Coronary artery calcium in HIV-infected men treated with highly active antiretroviral therapy

Calcium is a common component of an atherosclerotic plaque; therefore, the presence of coronary artery calcium (CAC) indicates atherosclerosis. This study investigated the difference in total CAC scores between HIV-infected patients treated with highly active antiretroviral therapy (HAART) and HIV-negative age-matched controls. HIV patients were 27 men treated with a protease inhibitor-containing HAART regimen for more than 1 year (M = 4.92 years, SD = 2.02), aged 30 to 60 years (M = 43.52 years, SD = 6.65), and not receiving lipid-lowering or hypoglycemic drugs. Controls were age-matched men randomly selected (three controls to one case, for a total of 81 controls) from our existing database of 25,250 men who self-referred for CAC screening (control database). Electron beam tomography was used to obtain CAC scores. The CAC scores were coded as above or below the age-specific (stratified in 5-year increments) 10th, 25th, 50th, 75th, or 90th percentile of our control database. Chi-square analyses for two independent samples indicated (1) a larger frequency of controls with CAC scores above the 10th (chi1= 8.32, P = .004) and 25th (chi1= 5.45, P = .02) percentiles than that of HIV patients, (2) no differences in CAC scores between groups above the 50th (chi = 0.85, P = .357) or 75th (chi = 0.46, P = .497) percentile, and (3) a larger frequency of HIV patients who were above the 90th percentile (chi = 4.5, P = .034). The strength of the relationship between group membership and scoring above the 90th percentile was significant (phi = 0.20, P = .034). These results tentatively suggest that there is an elevated level of subclinical atherosclerosis in HIV patients treated with HAART.

Cardiovascular implications of HIV-associated dyslipidemic lipodystrophy

The emergence of a new metabolic syndrome in patients with HIV infection, termed "HIV-associated dyslipidemic lipodystrophy" (HADL), is characterized by central fat redistribution, severe dyslipidemia, and insulin resistance and predisposes to an increased risk of cardiovascular disease. The factors promoting the development of cardiovascular disease in this condition are not well understood and may involve contributions from antiretroviral drugs and components of the HIV virus, as well as inflammatory cytokines, leading to accelerated lipolysis, dyslipidemia, lipotoxic insulin resistance, and vascular inflammation. In this article, we review HADL in terms of metabolic, molecular, and cytokine derangements leading to cardiovascular disease.