Use of cardiac CT angiography imaging in an epidemiology study - the Methodology of the Multicenter AIDS Cohort Study cardiovascular disease substudy

Epicardial and intra-thoracic adipose tissue and cardiovascular calcifications in type 1 diabetes (T1D) in epidemiology of diabetes Interventions and Complications (EDIC): A pilot study

Objective

Coronary artery, aortic valve, and descending aorta calcification (CAC, AVC, DAC) are manifestations of atherosclerosis, and cardiac epicardial adipose tissue (EAT) indicates heart adiposity. This study explored the association between cardiac adipose tissue and cardiovascular calcification in participants with long-standing T1D.

Methods

EAT and intra-thoracic adipose tissue (IAT) were measured in 100 T1D subjects with cardiac computed tomography (CT) scans in the EDIC study. Volume analysis software was used to measure fat volumes. Spearman correlations were calculated between CAC, AVC, DAC with EAT, and IAT. Associations were evaluated using multiple linear and logistic regression models.

Results

Participants ranged in age from 32 to 57. Mean EAT, and IAT were 38.5 and 50.8 mm3, respectively, and the prevalence of CAC, AVC, and DAC was 43.6 %, 4.7 %, and 26.8 %, respectively. CAC was positively correlated with age (p-value = 0.0001) and EAT (p-value = 0.0149) but not with AVC and DAC; IAT was not associated with calcified lesions. In models adjusted for age and sex, higher levels of EAT and IAT were associated with higher CAC (p-value < 0.0001 for both) and higher AVC (p-values of 0.0111 and 0.0053, respectively), but not with DAC. The associations with CAC remained significant (p-value < 0.0001) after further adjustment for smoking, systolic blood pressure, BMI, and LDL, while the associations with AVC did not remain significant.

Conclusion

In participants with T1D, higher EAT and IAT levels are correlated with higher CAC scores. EAT and IAT were not independently correlated with DAC or AVC.

A novel density-volume calcium score by non-contrast CT predicts coronary plaque burden on coronary CT angiography: Results from the MACS (Multicenter AIDS cohort study)

BACKGROUND

The purpose of this study is to determine if a new score calculated with coronary artery calcium (CAC) density and volume is associated with total coronary artery plaque burden and composition on coronary CT angiography (CCTA) compared to the Agatston score (AS).

METHODS

We identified 347 men enrolled in the Multicenter AIDS cohort study who underwent contrast and non-contrast CCTs, and had CAC>0. CAC densities (mean Hounsfield Units [HU]) per plaque) and volumes on non-contrast CCT were measured. A Density-Volume Calcium score was calculated by multiplying the plaque volume by a factor based on the mean HU of the plaque (4, 3, 2 and 1 for 130-199, 200-299, 300-399, and ≥400HU). Total Density-Volume Calcium score was determined by the sum of these individual scores. The semi-quantitative partially calcified and total plaque scores (PCPS and TPS) on CCTA were calculated. The associations between Density-Volume Calcium score, PCPS and TPS were examined.

RESULTS

Overall, 2879 CAC plaques were assessed. Multivariable linear regression models demonstrated a stronger association between the log Density-Volume Calcium score and both the PCPS (β 0.99, 95%CI 0.80-1.19) and TPS (β 2.15, 95%CI 1.88-2.42) compared to the log of AS (PCPS: β 0.77, 95%CI 0.61-0.94; TPS: β 1.70, 95%CI 1.48-1.94). Similar results were observed for numbers of PC or TP segments.

CONCLUSION

The new CAC score weighted towards lower density demonstrated improved correlation with semi-quantitative PC and TP burden on CCTA compared to the traditional AS, which suggests it has utility as an alternative measure of atherosclerotic burden.

Subclinical cardiovascular disease in HIV controller and long-term nonprogressor populations

OBJECTIVES

Elite controllers (ECs), viraemic controllers (VCs), and long-term nonprogressors (LTNPs) control HIV viral replication or maintain CD4 T-cell counts without antiretroviral therapy, but may have increased cardiovascular disease (CVD) risk compared to HIV-uninfected persons. We evaluated subclinical carotid and coronary atherosclerosis and inflammatory biomarker levels among HIV controllers, LTNPs and noncontrollers and HIV-uninfected individuals in the Multicenter AIDS Cohort Study (MACS) and the Women's Interagency HIV Study (WIHS).

METHODS

We measured carotid plaque presence and common carotid artery intima-media thickness (IMT) in 1729 women and 1308 men, and the presence of coronary artery calcium and plaque in a subgroup of men. Associations between HIV control category and carotid and coronary plaque prevalences were assessed by multivariable regression analyses adjusting for demographics and CVD risk factors. Serum inflammatory biomarker concentrations [soluble CD163 (sCD163), soluble CD14 (sCD14), galectin-3 (Gal-3), galectin-3 binding protein (Gal-3BP) and interleukin (IL)-6] were measured and associations with HIV control category assessed.

RESULTS

We included 135 HIV controllers (30 ECs) and 135 LTNPs in the study. Carotid plaque prevalence and carotid IMT were similar in HIV controllers, LTNPs and HIV-uninfected individuals. HIV controllers and LTNPs had lower prevalences of carotid plaque compared to viraemic HIV-infected individuals. The prevalence of coronary atherosclerosis was similar in HIV controllers/LTNPs compared to HIV-uninfected and viraemic HIV-infected men. Controllers and LTNPs had higher concentrations of sCD163 and sCD14 compared to HIV-uninfected persons.

CONCLUSIONS

Subclinical CVD was similar in HIV controllers, LTNPs and HIV-uninfected individuals despite elevated levels of some inflammatory biomarkers. Future studies of HIV controllers and LTNPs are needed to characterize the risk of CVD among HIV-infected persons.

Association of High-Sensitivity Troponin with Cardiac CT Angiography Evidence of Myocardial and Coronary Disease in a Primary Prevention Cohort of Men: Results from MACS

BACKGROUND

High-sensitivity cardiac troponin (hs-cTn) elevations are associated with incident cardiovascular disease events in primary prevention samples. However, the mechanisms underlying this association remain unclear.

METHODS

We studied 458 men without known cardiovascular disease who participated in the cardiovascular disease substudy of the Multicenter AIDS Cohort Study and had cardiac CT angiography. We used multivariable linear and logistic regression models to examine the cross-sectional associations between coronary artery stenosis, coronary artery plaque, indexed left ventricular mass (LVMi), and the outcome of hs-cTnI. We also evaluated the associations between HIV serostatus or use of highly active antiretroviral therapy (HAART) and hs-cTnI.

RESULTS

The mean age was 54 years, 54% were white, and 61% were HIV infected. In multivariable-adjusted logistic models, comparing the highest quartile of LVMi with the lowest quartile, the odds ratio (OR) of hs-cTnI ≥75th percentile was 2.59 (95% CI, 1.20-5.75). There was no significant association between coronary stenosis severity or plaque type and hs-cTnI in linear models; however, in logistic regression models, coronary artery stenosis ≥70% (8% of sample) was marginally associated with a higher likelihood (OR, 2.75 [95% CI, 1.03, 7.27]) of having hs-cTnI ≥75th percentile. There were no associations between HIV serostatus or HAART use and hs-cTnI in either linear or logistic models.

CONCLUSION

Among primary prevention men with or at risk for HIV, hs-cTnI concentrations were strongly associated with LVMi but were not associated with HIV infection or treatment status or with coronary plaque type or stenosis until the extremes of severity (≥70% stenosis).

Associations between subcutaneous fat density and systemic inflammation differ by HIV serostatus and are independent of fat quantity

OBJECTIVES

Adipose tissue (AT) density measurement may provide information about AT quality among people living with HIV. We assessed AT density and evaluated relationships between AT density and immunometabolic biomarker concentrations in men with HIV.

DESIGN

Cross-sectional analysis of men enrolled in the Multicenter AIDS Cohort Study.

METHODS

Abdominal visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) density (Hounsfield units, HU; less negative = more dense) were quantified from computed tomography (CT) scans. Multivariate linear regression models described relationships between abdominal AT density and circulating biomarker concentrations.

RESULTS

HIV+ men had denser SAT (-95 vs -98 HU HIV-, P < 0.001), whereas VAT density was equivalent by HIV serostatus men (382 HIV-, 462 HIV+). Historical thymidine analog nucleoside reverse transcriptase inhibitor (tNRTI) use was associated with denser SAT but not VAT. In adjusted models, a 1 s.d. greater SAT or VAT density was associated with higher levels of adiponectin, leptin, HOMA-IR and triglyceride:HDL cholesterol ratio and lower hs-CRP concentrations in HIV- men. Conversely, in HIV+ men, each s.d. greater SAT density was not associated with metabolic parameter improvements and was significantly (P < 0.05) associated with higher systemic inflammation. Trends toward higher inflammatory biomarker concentrations per 1 s.d. greater VAT density were also observed among HIV+ men.

CONCLUSIONS

Among men living with HIV, greater SAT density was associated with greater systemic inflammation independent of SAT area. AT density measurement provides additional insight into AT density beyond measurement of AT quantity alone, and may have implications for metabolic disease risk.

HIV Infection Is Associated with Greater Left Ventricular Mass in the Multicenter AIDS Cohort Study

HIV infection has been associated with diastolic heart failure and atrial fibrillation. The purpose of this study is to determine whether HIV infection is associated with differences in left ventricular mass (LVM), left ventricular end-diastolic volume (LVEDV), and left atrial volume (LAV) indexed to body surface area (left ventricular mass index, left ventricular end-diastolic volume index [LVEDVI], and left atrial volume index [LAVI], respectively). Cross-sectional study of 721 men [425 HIV-infected (HIV+), 296 HIV-uninfected (HIV-) enrolled in the cardiovascular substudy of the Multicenter AIDS Cohort Study (MACS). Participants underwent cardiac computed tomography imaging. A blinded reader measured LVM, LVEDV, and LAV. We used multivariable linear regression models to evaluate whether LVEDVI, left ventricular mass index (LVMI), and LAVI differed by HIV serostatus, adjusting for demographics and cardiovascular disease risk factors. LVMI was significantly greater in HIV+ compared with HIV- men, with adjusted difference of 2.65 g/m2 (95% confidence interval 0.53-4.77, p < .001). Left ventricular end-diastolic index and LAVI did not differ significantly between the two groups. HIV-related factors (nadir CD4 count, clinical AIDS diagnosis, cumulative antiretroviral therapy use, and cumulative protease inhibitor use) were not significantly associated with LVMI, LVEDVI, or LAVI. LVM was significantly higher in HIV+ than HIV- men, which may contribute to the observed increased risk for diastolic heart failure associated with HIV infection. Although HIV infection has been associated with an increased risk for atrial fibrillation, we did not find any difference in LAV by HIV serostatus.

Associations between lipids and subclinical coronary atherosclerosis

OBJECTIVE

Whether HIV modifies the relationship of serum lipids with coronary atherosclerosis and coronary plaque subtypes is uncertain. We examined the associations between traditional lipids and coronary atherosclerosis among HIV-infected (HIV+) and HIV-uninfected (HIV-) men.

DESIGN

The Multicenter AIDS Cohort Study is an observational cohort with a total of 429 HIV+ and 303 HIV- men who had non-contrast cardiac computed tomography performed to measure coronary artery calcium and coronary computed tomography angiography to measure coronary stenosis, coronary plaque presence, and composition.

METHODS

We used multivariable adjusted prevalence ratios to examine the relationship between the SD difference in each lipid parameter and coronary atherosclerosis.

RESULTS

Total cholesterol (TC)/HDL-cholesterol had the strongest associations with coronary atherosclerosis regardless of HIV status. Overall, lipid parameters were most strongly associated with the presence of mixed plaque, stenosis more than 50%, and coronary artery calcium for both HIV+ and HIV- men. HIV+ men had similar, but weaker associations, between lipid parameters and coronary atherosclerosis compared with HIV- men. The strongest association was between the TC/HDL-cholesterol and stenosis more than 50% for both HIV+ [prevalence ratios 1.25 per SD (95% confidence interval 1.07-1.43)] and HIV- men [prevalence ratios 1.46 per SD (95% confidence interval 1.08-1.85)].

CONCLUSION

The associations between lipids and coronary atherosclerosis tended to be weaker for HIV+ compared with HIV- men, although TC/HDL had the strongest association for both HIV+ and HIV- men. A weaker association between lipid levels and coronary atherosclerosis for HIV+ men may contribute to the decreased discrimination of cardiovascular disease risk observed in HIV+ individuals.

Inflammatory biomarkers and subclinical carotid atherosclerosis in HIV-infected and HIV-uninfected men in the Multicenter AIDS Cohort Study

BACKGROUND

HIV-infected persons have an increased risk of atherosclerosis relative to uninfected individuals. Inflammatory processes may contribute to this risk. We evaluated the associations of 10 biomarkers of systemic inflammation (CRP, IL-6, sTNF-αR1 and 2), monocyte activation (CCL2, sCD163, sCD14), coagulation (fibrinogen, D-dimer), and endothelial dysfunction (ICAM-1) with subclinical carotid atherosclerosis among participants in the Multicenter AIDS Cohort Study (MACS).

METHODS

Carotid plaque and intima media thickness (IMT) in the common carotid (CCA-IMT) and bifurcation region were assessed by B mode ultrasound among 452 HIV-infected and 276 HIV-uninfected men from 2010-2013. Associations between levels of each biomarker and presence of focal plaque and IMT were assessed by logistic and linear regression models, adjusting for demographics, risk behaviors, traditional cardiovascular disease (CVD) risk factors, and HIV disease characteristics.

RESULTS

Compared to HIV-uninfected men, HIV-infected men had significantly higher levels of 8 of the 10 biomarkers. Overall, men with sCD163, CCL2, IL-6, and CRP levels in the highest quintile had approximately 2 times the odds of carotid plaque relative to those with levels in the lowest quintile, independent of demographic and CVD risk factors. Fibrinogen levels were positively associated with CCA-IMT while ICAM-1, CCL2, and sTNF-αR1 levels were positively associated with bifurcation-IMT. Among HIV-uninfected men, higher levels of sTNF-αR2 were positively associated with CCA-IMT, fibrinogen with bifurcation-IMT and carotid plaque, and ICAM-1 with carotid plaque.

CONCLUSION

In addition to greater levels of systemic inflammation, heightened monocyte activation (sCD163, CCL2) may contribute to the burden of atherosclerosis among HIV-infected persons.

GlycA, a novel inflammatory marker, is associated with subclinical coronary disease

OBJECTIVE

GlycA, a novel NMR biomarker of inflammation, has been associated with incident cardiovascular disease (CVD) in the general population, but its association with CVD among HIV-infected individuals is unknown. We examined the associations between GlycA and subclinical coronary plaque among HIV-infected and HIV-uninfected men participating in Multicenter AIDS Cohort Study (MACS).

DESIGN

Cross-sectional analysis of 935 men with plasma measurement of GlycA and noncontrast cardiac computed tomography (CT) and/or coronary CT angiography.

METHODS

We used multivariable Poisson and linear regression to assess associations of GlycA with prevalent coronary atherosclerosis and plaque extent, respectively.

RESULTS

Mean ± SD age was 54 ± 7 years; 31% were black; 63% HIV-infected. GlycA levels were higher in HIV-infected compared with HIV-uninfected men (397 ± 68 vs. 380 ± 60 μmol/l, P = 0.0001) and higher for men with detectable viral load vs. undetectable (413 ± 79 vs. 393 ± 65 μmol/l, P = 0.004). After adjusting for HIV serostatus, demographic and CVD risk factors, every 1SD increment in GlycA level was associated with a higher prevalence of coronary artery calcium (CAC >0) [prevalence ratio 1.09 (95% CI 1.03-1.15)] and coronary stenosis at least 50% [1.20 (1.02-1.41)]. These associations were not significantly altered after adjusting for traditional inflammatory biomarkers or differ by HIV serostatus. Among men with plaque, GlycA was positively associated with the extent of CAC and total plaque.

CONCLUSION

HIV infection was associated with higher GlycA levels. In both HIV-infected and HIV-uninfected individuals, GlycA was significantly associated with several measures of subclinical coronary atherosclerosis, independent of other CVD risk factors and inflammatory biomarkers. These findings suggest the potential role of GlycA in CVD risk stratification among HIV patients.

Multicenter AIDS Cohort Study Quantitative Coronary Plaque Progression Study: rationale and design

BACKGROUND AND AIM

The association of HIV with coronary atherosclerosis has been established; however, the progression of coronary atherosclerosis over time among participants with HIV is not well known. The Multicenter AIDS Cohort Study Quantitative Coronary Plaque Progression Study is a large prospective multicenter study quantifying progression of coronary plaque assessed by serial coronary computed tomography angiography (CTA).

PATIENTS AND METHODS

HIV-infected and uninfected men who were enrolled in the Multicenter AIDS Cohort Study Cardiovascular Substudy were eligible to complete a follow-up contrast coronary CTA 3-6 years after baseline. We measured coronary plaque volume and characteristics (calcified and noncalcified plaque including fibrous, fibrous-fatty, and low attenuation) and vulnerable plaque among HIV-infected and uninfected men using semiautomated plaque software to investigate the progression of coronary atherosclerosis over time.

CONCLUSION

We describe a novel, large prospective multicenter study investigating incidence, transition of characteristics, and progression in coronary atherosclerosis quantitatively assessed by serial coronary CTAs among HIV-infected and uninfected men.

Low thigh muscle mass is associated with coronary artery stenosis among HIV-infected and HIV-uninfected men: The Multicenter AIDS Cohort Study (MACS)

BACKGROUND

HIV-infected individuals are at increased risk for both sarcopenia and cardiovascular disease. Whether an association between low muscle mass and subclinical coronary artery disease (CAD) exists, and if it is modified by HIV serostatus, are unknown.

METHODS

We performed cross-sectional analysis of 513 male MACS participants (72% HIV-infected) who underwent mid-thigh computed tomography (CT) and non-contrast cardiac CT for coronary artery calcium (CAC) during 2010-2013. Of these, 379 also underwent coronary CT angiography for non-calcified coronary plaque (NCP) and obstructive coronary stenosis ≥50%. Multivariable-adjusted Poisson regression was used to estimate prevalence risk ratios of associations between low muscle mass (<20th percentile of the HIV-uninfected individuals in the sample) and CAC, NCP and obstructive stenosis.

RESULTS

The prevalence of low thigh muscle mass was similar by HIV serostatus (20%). There was no association of low muscle mass with CAC or NCP. However, low thigh muscle mass was significantly associated with a 2.5-fold higher prevalence of obstructive coronary stenosis, after adjustment for demographics and traditional CAD risk factors [PR 2.46 (95% CI 1.51, 4.01)]. This association remained significant after adjustment for adiposity, inflammation, and physical activity. There was no significant interaction by HIV serostatus (p-interaction = 0.90).

CONCLUSIONS

In this exploratory analysis, low thigh muscle mass was significantly associated with subclinical obstructive coronary stenosis. Additional studies involving larger sample sizes and prospective analyses are needed to confirm the potential utility of measuring mid-thigh muscle mass for identifying individuals at increased risk for obstructive CAD who might benefit from more aggressive risk factor management.

Frailty and subclinical coronary atherosclerosis: The Multicenter AIDS Cohort Study (MACS)

BACKGROUND AND AIMS

Frailty and cardiovascular disease share many risk factors. We evaluated whether frailty is independently associated with subclinical coronary atherosclerosis and whether any relationships differ by HIV-serostatus.

METHODS

We studied 976 [62% HIV-infected] male participants of the Multicenter AIDS Cohort Study who underwent assessment of frailty and non-contrast cardiac CT scanning; of these, 747 men also underwent coronary CT angiography (CCTA). Frailty was defined as having ≥3 of 5 of the following: weakness, slowness, weight loss, exhaustion, and low physical activity. Coronary artery calcium (CAC) was assessed by non-contrast CT, and total plaque score (TPS), mixed plaque score (MPS), and non-calcified plaque score (NCPS) by CCTA. Multivariable-adjusted regression was used to assess the cross-sectional associations between frailty and subclinical coronary atherosclerosis.

RESULTS

Mean (SD) age of participants was 54 (7) years; 31% were black. Frailty existed in 7.5% and 14.3% of HIV-uninfected and HIV-infected men, respectively. After adjustment for demographics, frailty was significantly associated with prevalence of any CAC (CAC>0), any plaque (TPS>0), and mixed plaque (MPS>0) in HIV-uninfected but not in HIV-infected men (p-interaction_HIV<0.05 for all). Among HIV-uninfected men, after adjustment for cardiovascular risk factors, frailty was significantly associated only with CAC>0 [Prevalence Ratio 1.27 (95%CI 1.02, 1.59)] and TPS>0 [1.19 (1.06, 1.35)]. No association was found for NCPS.

CONCLUSIONS

Frailty was independently associated with subclinical coronary atherosclerosis among HIV-uninfected men, but not among HIV-infected men. Further work is needed to ascertain mechanisms underlying these differences and whether interventions that improve frailty (i.e. strength training) can improve cardiovascular outcomes.

Glomerular filtration rate and proteinuria associations with coronary artery calcium among HIV-infected and HIV-uninfected men in the Multicenter AIDS Cohort Study

BACKGROUND

Decreased kidney function and greater albuminuria are associated with increased incidence and extent of coronary artery calcium (CAC). We investigated whether the associations between kidney function and urine protein-to-creatinine ratio (UPCR) with CAC differ by HIV serostatus.

METHODS

Using data from the Multicenter AIDS Cohort Study, a prospective multicenter US study of men who have sex with men, we carried out a cross-sectional study comprised of 592 HIV-infected (HIV+) and 378 uninfected (HIV-) men who underwent noncontrast computed tomography to measure CAC. Logistic and linear regression models were used to determine whether HIV infection modified associations of estimated glomerular filtration rate and UPCR with the presence and extent of CAC, adjusting for age, race, and cardiovascular risk factors.

RESULTS

Every 10 U decrease in estimated glomerular filtration rate below 90 ml/min/1.73 m was significantly associated with 1.3-fold [95% confidence interval (CI): 1.06-1.51] higher odds of CAC presence and was similar by HIV serostatus (Pinteraction=0.37). Greater UPCR was associated with more extensive CAC, with a change in log CAC score of 0.32 (95% CI: 0.10-0.55) per 1% increase in UPCR. There was a strong trend for effect modification by HIV serostatus for this association [HIV-: 0.75 (95% CI: 0.26-1.25); HIV+: 0.22 (95% CI: -0.03 to 0.47), Pinteraction=0.06].

CONCLUSION

Greater CAC burden is apparent among individuals with early kidney disease, irrespective of HIV serostatus. Increased UPCR is associated with a greater extent of CAC with a trend for differences by HIV serostatus; a clearer proteinuria/CAC extent relationship was apparent among HIV- patients.

Visceral fat is associated with brain structure independent of human immunodeficiency virus infection status

The combined effects of human immunodeficiency virus (HIV), obesity, and elevated visceral adipose tissue (VAT) on brain structure are unknown. In a cross-sectional analysis of Multicenter AIDS Cohort Study (MACS) participants, we determined associations between HIV serostatus, adiposity, and brain structure. Men (133 HIV+, 84 HIV-) in the MACS Cardiovascular 2 and magnetic resonance imaging (MRI) sub-studies with CT-quantified VAT and whole brain MRI measured within 1 year were assessed. Voxel-based morphometry analyzed brain volumes. Men were stratified by elevated (eVAT, ≥100cm²) or "normal" (nVAT, <100cm²) VAT. Forward stepwise modeling determined associations between clinical and demographic variables and regional brain volumes. eVAT was present in 67% of men. Groups were similar in age and education, but eVAT men were more likely to be HIV+ and have hypertension, diabetes mellitus, body mass index >25 kg/m², smaller gray and white matter volumes, and larger cerebrospinal fluid volume than nVAT men. In multivariate analysis, hypertension, higher adiponectin, higher interleukin-6, age, diabetes mellitus, higher body mass index, and eVAT were associated with brain atrophy (p < 0.05, ordered by increasing strength of association), but HIV serostatus and related factors were generally not. No interactions were observed. Greater VAT was associated with smaller bilateral posterior hippocampus and left mesial temporal lobe and temporal stem white matter volume. Traditional risk factors are more strongly associated with brain atrophy than HIV serostatus, with VAT having the strongest association. However, HIV+ MACS men had disproportionately greater VAT, suggesting the risk for central nervous system effects may be amplified in this population.

Associations between antiretroviral use and subclinical coronary atherosclerosis

OBJECTIVES

HIV infection is associated with increased prevalence of subclinical coronary plaque. The extent to which such plaque reflects effects of HIV infection or effects of long-term antiretroviral therapy (ART) use remains unclear and was the goal of this analysis.

DESIGN AND METHODS

We compared the prevalence and extent of coronary plaque and stenosis between users of specific ART drugs or drug classes using coronary computed tomography (CT) among HIV-infected men in the Multicenter AIDS Cohort Study. To account for time-dependent confounders, including cardiovascular disease risk factors and time-varying reasons for using specific treatments, we conducted fully adjusted logistic and linear models with inverse probability of treatment weighting.

RESULTS

There were 618 men who underwent noncontrast coronary CT; 450 also underwent coronary CT angiography. At the time of scanning, 81% had undetectable plasma HIV RNA. In fully adjusted models, cumulative use of zidovudine, abacavir, darunavir, and protease inhibitors as a drug class were inconsistently associated with specific forms of plaque presence or extent.

CONCLUSION

Among virally suppressed HIV-infected men with extensive ART exposure, no consistent associations between use of specific ART drugs and both subclinical coronary plaque presence and extent were apparent. Our findings support the hypothesis that, among virally suppressed persons, type of ART used is not in general a major determinant of subclinical coronary plaque risk.

Brief Report: Intestinal Microbiota-Produced Trimethylamine-N-Oxide and Its Association With Coronary Stenosis and HIV Serostatus

Recent evidence has shown a complex relationship between the gut microbiota, dietary nutrients, and cardiovascular disease (CVD). Trimethylamine-N-oxide (TMAO) production, initiated by the microbiota, has been associated with CVD events. We sought to test if this association exists in HIV-infected persons. After adjusting for aspirin use and CVD risk factors, HIV-infected men were more likely to have coronary stenosis in the second and third TMAO quartiles compared with the first quartile, but did not differ significantly in the fourth quartile. We found an inverted U-shaped association between TMAO levels and the presence of coronary artery stenosis among HIV-infected men.

Cardiovascular disease risk scores' relationship to subclinical cardiovascular disease among HIV-infected and HIV-uninfected men

OBJECTIVE

To study cardiovascular disease risk score utility, we compared the association between Framingham Risk Score (FRS)/pooled cohort equation (PCE) categories and coronary artery plaque presence by HIV serostatus and evaluated whether D : A : D risk category more accurately identifies plaque in HIV-infected men.

DESIGN

Cross-sectional analysis within a substudy of the Multicenter AIDS Cohort Study.

METHODS

Cardiac computed tomography was performed to assess coronary plaque. We evaluated the association of plaque with increasing cardiovascular disease risk score category, stratified by HIV serostatus, using logistic regression. Receiver operating characteristic curves compared the discrimination of the scores for plaque by HIV serostatus. The sensitivity and specificity of the risk scores were compared in HIV-infected men.

RESULTS

The risk score category - plaque associations were stronger among HIV-uninfected men than HIV-infected men, except for noncalcified plaque. For example, the odds of coronary artery calcium more than 0 were 7.03 (95% confidence interval 4.21, 11.76) times greater among men in the PCE high-risk versus low-risk category among HIV-uninfected men, compared with just 3.13 (95% confidence interval 2.13, 4.61) times greater among men in the high-risk versus low-risk category among HIV-infected men. Among HIV-infected men, high-risk category by PCE identified the greatest percentage of men with plaque/stenosis, but with lower specificity than D : A : D and FRS. The prevalence of coronary artery calcium more than 0 among men in the PCE low-risk category was 26.5% (HIV-uninfected men) and 36.0% (HIV-infected men).

CONCLUSIONS

FRS and PCE categories associate with plaque burden better in HIV-uninfected men. No risk score delivered both high sensitivity and specificity among HIV-infected men.

Inflammatory Markers Associated With Subclinical Coronary Artery Disease: The Multicenter AIDS Cohort Study

Background

Despite evidence for higher risk of coronary artery disease among HIV+ individuals, the underlying mechanisms are not well understood. We investigated associations of inflammatory markers with subclinical coronary artery disease in 923 participants of the Multicenter AIDS Cohort Study (575 HIV+ and 348 HIV− men) who underwent noncontrast computed tomography scans for coronary artery calcification, the majority (n=692) also undergoing coronary computed tomography angiography.

Methods and Results

Outcomes included presence and extent of coronary artery calcification, plus computed tomography angiography analysis of presence, composition, and extent of coronary plaques and severity of coronary stenosis. HIV+ men had significantly higher levels of interleukin‐6 (IL‐6), intercellular adhesion molecule‐1, C‐reactive protein, and soluble‐tumor necrosis factor‐α receptor (sTNFαR) I and II (all P<0.01) and a higher prevalence of noncalcified plaque (63% versus 54%, P=0.02) on computed tomography angiography. Among HIV+ men, for every SD increase in log‐interleukin‐6 and log intercellular adhesion molecule‐1, there was a 30% and 60% increase, respectively, in the prevalence of coronary stenosis ≥50% (all P<0.05). Similarly, sTNFαR I and II in HIV+ participants were associated with an increase in prevalence of coronary stenosis ≥70% (P<0.05). Higher levels of interleukin‐6, sTNFαR I, and sTNFαR II were also associated with greater coronary artery calcification score in HIV+ men (P<0.01).

Conclusions

Higher inflammatory marker levels are associated with greater prevalence of coronary stenosis in HIV+ men. Our findings underscore the need for further study to elucidate the relationships of inflammatory pathways with coronary artery disease in HIV+ individuals.

Anatomic Fat Depots and Coronary Plaque Among Human Immunodeficiency Virus-Infected and Uninfected Men in the Multicenter AIDS Cohort Study

Methods. In a cross-sectional substudy of the Multicenter AIDS Cohort Study, noncontrast cardiac computed tomography (CT) scanning for coronary artery calcium (CAC) scoring was performed on all men, and, for men with normal renal function, coronary CT angiography (CTA) was performed. Associations between fat depots (visceral adipose tissue [VAT], abdominal subcutaneous adipose tissue [aSAT], and thigh subcutaneous adipose tissue [tSAT]) with coronary plaque presence and extent were assessed with logistic and linear regression adjusted for age, race, cardiovascular disease (CVD) risk factors, body mass index (BMI), and human immunodeficiency virus (HIV) parameters.

Results. Among HIV-infected men (n = 597) but not HIV-uninfected men (n = 343), having greater VAT was positively associated with noncalcified plaque presence (odds ratio [OR] = 1.04, P < .05), with a significant interaction (P < .05) by HIV serostatus. Human immunodeficiency virus-infected men had lower median aSAT and tSAT and greater median VAT among men with BMI <25 and 25–29.9 kg/m². Among HIV-infected men, VAT was positively associated with presence of coronary plaque on CTA after adjustment for CVD risk factors (OR = 1.04, P < .05), but not after additional adjustment for BMI. There was an inverse association between aSAT and extent of total plaque among HIV-infected men, but not among HIV-uninfected men. Lower tSAT was associated with greater CAC and total plaque score extent regardless of HIV serostatus.

Conclusions. The presence of greater amounts of VAT and lower SAT may contribute to increased risk for coronary artery disease among HIV-infected persons.

Comparison of Insulin Resistance to Coronary Atherosclerosis in Human Immunodeficiency Virus Infected and Uninfected Men (from the Multicenter AIDS Cohort Study)

The relation between insulin resistance (IR) and coronary artery disease in patients with human immunodeficiency virus (HIV) infection remains incompletely defined. Fasting serum insulin and glucose measurements from 448 HIV-infected and 306 uninfected men enrolled in the Multicenter AIDS Cohort Study were collected at semiannual visits from 2003 to 2013 and used to compute the homeostatic model assessment of IR (HOMA-IR). Coronary computed tomographic angiography (CTA) was performed at the end of the study period to characterize coronary pathology. Associations between HOMA-IR (categorized into tertiles and assessed near the time of the CTA and over the 10-year study period) and the prevalence of coronary plaque or stenosis ≥50% were assessed with multivariate logistic regression. HOMA-IR was higher in HIV-infected men than HIV-uninfected men when measured near the time of CTA (3.2 vs 2.7, p = 0.002) and when averaged over the study period (3.4 vs 3.0, p <0.001). The prevalence of coronary stenosis ≥50% was similar between both groups (17% vs 15%, p = 0.41). Both measurements of HOMA-IR were associated with greater odds of coronary stenosis ≥50% in models comparing men with values in the highest versus the lowest tertiles, although the effect of mean HOMA-IR was stronger than the single measurement of HOMA-IR before CTA (odds ratio 2.46, 95% CI 1.95 to 3.11, vs odds ratio 1.43, 1.20 to 1.70). This effect was not significantly modified by HIV serostatus. In conclusion, IR over nearly a decade was greater in HIV-infected men than HIV-uninfected men, and in both groups, was associated with significant coronary artery stenosis.

Extra-coronary calcification (aortic valve calcification, mitral annular calcification, aortic valve ring calcification and thoracic aortic calcification) in HIV seropositive and seronegative men: Multicenter AIDS Cohort Study

INTRODUCTION

Previous studies have demonstrated an association between HIV infection and coronary artery disease (CAD); little is known about potential associations between HIV infection and extra-coronary calcification (ECC).

METHODS

We analyzed 621 HIV infected (HIV+) and 384 HIV uninfected (HIV-) men from the Multicenter AIDS Cohort Study who underwent non-contrast computed tomography (CT) from 2010-2013. Agatston scores were calculated for mitral annular calcification (MAC), aortic valve calcification (AVC), aortic valve ring calcification (AVRC), and thoracic aortic calcification (TAC). The associations between HIV infection and the presence of each type of ECC (score > 0) were evaluated by multivariable logistic regression. We also evaluated the association of ECC with inflammatory biomarker levels and coronary plaque morphology.

RESULTS

Among HIV+ and HIV- men, the age-standardized prevalences were 15% for TAC (HIV+ 14%/HIV- 16%), 10% for AVC (HIV+ 11%/HIV- 8%), 24% for AVRC (HIV+ 23% HIV- 24%), and 5% for MAC (HIV+ 7%/HIV- 3%). After adjustment, HIV+ men had 3-fold greater odds of MAC compared to HIV- men (OR = 3.2, 95% CI: 1.5-6.7), and almost twice the odds of AVC (1.8, 1.1-2.9). HIV serostatus was not associated with TAC or AVRC. AVRC was associated with higher Il-6 and sCD163 levels. TAC was associated with higher ICAM-1, TNF-α RII, and Il-6 levels. AVC and AVRC calcification were associated with presence of non-calcified plaque in HIV+ but not HIV- men.

CONCLUSION

HIV infection is an independent predictor of MAC and AVC. Whether these calcifications predict mortality in HIV+ patients deserves further investigation.

Osteoprotegerin, but Not Receptor Activator for Nuclear Factor-κB Ligand, is Associated With Subclinical Coronary Atherosclerosis in HIV-Infected Men

CONTEXT

Abnormalities in the osteoprotegerin (OPG)/receptor activator of nuclear factor-κB ligand (RANKL) axis have been observed in HIV-infected persons and have been implicated in cardiovascular disease (CVD) pathogenesis in the general population.

OBJECTIVE

To determine associations of serum OPG and RANKL concentrations with HIV infection and subclinical atherosclerosis.

DESIGN

Cross-sectional study nested within the Multicenter AIDS Cohort Study.

SETTING

Four US academic medical centers.

PARTICIPANTS

There were 578 HIV-infected and 344 HIV-uninfected men.

MAIN OUTCOME MEASURES

Coronary artery calcium (CAC) was measured by noncontrast cardiac computed tomography, and coronary stenosis and plaque characteristics (composition, presence, and extent) were measured by coronary computed tomography angiography. All statistical models were adjusted for traditional CVD risk factors.

RESULTS

OPG concentrations were higher, and RANKL concentrations were lower among HIV-infected men compared with HIV-uninfected men (P < 0.0001 each). Among HIV-infected men, higher OPG concentrations were associated with the presence of CAC, mixed plaque, and coronary stenosis >50%, but not with plaque extent. In contrast, among HIV-uninfected men, higher OPG concentrations were associated with the extent of both CAC and calcified plaque, but not with their presence. RANKL concentrations were not associated with plaque presence or the extent among HIV-infected men, but among HIV-uninfected men, lower RANKL concentrations were associated with greater extent of CAC and total plaque.

CONCLUSIONS

OPG and RANKL are dysregulated in HIV-infected men, and their relationship to the presence and extent of subclinical atherosclerosis varies by HIV status. The role of these biomarkers in CVD pathogenesis and risk prediction may be different in HIV-infected men.

Associations between Tobacco, Alcohol, and Drug Use with Coronary Artery Plaque among HIV-Infected and Uninfected Men in the Multicenter AIDS Cohort Study

BACKGROUND

We characterized associations between smoking, alcohol, and recreational drug use and coronary plaque by HIV serostatus within the Multicenter AIDS Cohort Study (MACS).

METHODS

MACS participants (N = 1005, 621 HIV+ and 384 HIV-) underwent non-contrast CT scanning to measure coronary artery calcium; 764 underwent coronary CT angiograms to evaluate plaque type and extent. Self-reported use of alcohol, tobacco, smoked/inhaled cocaine, methamphetamine, ecstasy, marijuana, inhaled nitrites, and erectile dysfunction drugs was obtained at semi-annual visits beginning 10 years prior to CT scanning. Multivariable logistic and linear regression models were performed, stratified by HIV serostatus.

RESULTS

Among HIV+ men, current smoking, former smoking, and cumulative pack years of smoking were positively associated with multiple coronary plaque measures (coronary artery calcium presence and extent, total plaque presence and extent, calcified plaque presence, and stenosis >50%). Smoking was significantly associated with fewer plaque measures of comparable effect size among HIV- men; current smoking and calcified plaque extent was the only such association. Heavy alcohol use (>14 drinks/week) was associated with stenosis >50% among HIV+ men. Among HIV- men, low/moderate (1-14 drinks/week) and heavy alcohol use were inversely associated with coronary artery calcium and calcified plaque extent. Few significant associations between other recreational drug use and plaque measures were observed.

CONCLUSION

Smoking is strongly associated with coronary plaque among HIV+ men, underscoring the value of smoking cessation for HIV+ persons. Alcohol use may protect against coronary artery calcium and calcified plaque progression in HIV- (but not HIV+) men. Few positive associations were observed between recreational drug use and coronary plaque measures.

Incidence and progression of coronary artery calcium in HIV-infected and HIV-uninfected men

OBJECTIVE

The aim of this article is to determine whether HIV-infected (HIV+) men have either higher incidence or more rapid progression of coronary artery calcium (CAC) compared with HIV-uninfected (HIV-) controls.

DESIGN

Prospective observational study.

SETTING

Multicenter study in four US academic research centers: University of Pittsburgh, Johns Hopkins University, University of California Los Angeles, and Northwestern University.

PARTICIPANTS

Eight hundred and twenty-five men (541 HIV+ and 284 HIV-) enrolled in the cardiovascular substudy of the Multicenter AIDS Cohort Study who underwent serial cardiac computed tomography (CT) imaging during a mean follow-up of 5 years (range, 2-8 years).

MAIN OUTCOME MEASURES

Incidence and progression of CAC assessed by cardiac CT.

RESULTS

During follow-up, 21% of HIV+ men developed incident CAC compared with 16% of HIV- men. This association persisted after adjustment for traditional and HIV-associated risk factors: hazard ratio 1.64 (1.13-3.14). However, there was no association between HIV serostatus and CAC progression among men with CAC present at baseline. Current smoking and increased insulin resistance, both modifiable risk factors, were independently associated with increased incidence of CAC. No evidence supporting an elevated risk for either CAC progression or incidence was found for either dyslipidemia or long-term usage of antiretroviral therapy.

CONCLUSION

In this large study of HIV+ and HIV- men who underwent serial cardiac CT scan imaging, HIV+ men were at significantly higher risk for development of CAC: hazard ratio 1.64 (1.13-3.14). In addition, two important and modifiable risk factors were identified for increased incidence of CAC. Taken together, these findings underscore the potential importance for smoking cessation and interventions to improve insulin resistance among HIV+ men.

A Cross-sectional Study of the Association Between Chronic Hepatitis C Virus Infection and Subclinical Coronary Atherosclerosis Among Participants in the Multicenter AIDS Cohort Study

BACKGROUND

Hepatitis C virus (HCV) infection may increase the risk of cardiovascular disease (CVD). We evaluated the association of chronic HCV infection and coronary atherosclerosis among participants in the Multicenter AIDS Cohort Study.

METHODS

We assessed 994 men with or without human immunodeficiency virus (HIV) infection (87 of whom had chronic HCV infection) for coronary plaque, using noncontrast coronary computed tomography (CT); 755 also underwent CT angiography. We then evaluated the associations of chronic HCV infection and HIV infection with measures of plaque prevalence, extent, and stenosis.

RESULTS

After adjustment for demographic characteristics, HIV serostatus, behaviors, and CVD risk factors, chronic HCV infection was significantly associated with a higher prevalence of coronary artery calcium (prevalence ratio, 1.29; 95% confidence interval [CI], 1.02-1.63), any plaque (prevalence ratio, 1.26; 95% CI, 1.09-1.45), and noncalcified plaque (prevalence ratio, 1.42; 95% CI, 1.16-1.75). Chronic HCV infection and HIV infection were independently associated with the prevalence of any plaque and of noncalcified plaque, but there was no evidence of a synergistic effect due to HIV/HCV coinfection. The prevalences of coronary artery calcium, any plaque, noncalcified plaque, a mixture of noncalcified and calcified plaque, and calcified plaque were significantly higher among men with an HCV RNA load of ≥2 × 10(6) IU/mL, compared with findings among men without chronic HCV infection.

CONCLUSIONS

Chronic HCV infection is associated with subclinical CVD, suggesting that vigilant assessments of cardiovascular risk are warranted for HCV-infected individuals. Future research should determine whether HCV infection duration or HCV treatment influence coronary plaque development.

HIV and coronary arterial remodeling from the Multicenter AIDS Cohort Study (MACS)

OBJECTIVE

Positive remodeling (PR), a coronary artery characteristic associated with risk for myocardial infarction (MI), may be more prevalent in HIV-infected (HIV+) people. We evaluated the prevalence of PR using coronary CT angiography (CCTA) in HIV+ and HIV-uninfected (HIV-) men.

METHODS

Men enrolled in the Multicenter AIDS Cohort Study underwent CCTA if they were 40-70 years, had normal kidney function and no history of coronary revascularization. Multivariable logistic regression models were used to estimate the odds ratio (OR) of PR by HIV serostatus, adjusting for demographics and coronary artery disease (CAD) risk factors. Analysis of PR among atherosclerotic segments further adjusted for plaque type and stenosis.

RESULTS

The prevalence of PR was 8.4% versus 12.1% (p = 0.10) for HIV- and HIV + men, respectively. After demographic adjustment, HIV + men had twice the odds of PR [OR 2.01(95% CI 1.20-3.38)], which persisted after CAD risk factor adjustment [1.76(1.00-3.10)]. Higher systolic blood pressure, total cholesterol, diabetes medication use, older age, segment number with plaque present, mixed and non-calcified plaque, and stenosis>50%, were associated with increased odds of PR, while higher HDL cholesterol, higher nadir CD4 count, and black race were associated with lower PR odds. Among atherosclerotic segments, the association between HIV infection and PR persisted, but was not statistically significantly.

CONCLUSION

HIV+ men have more positively remodeled arterial segments, which may be due to more coronary segments with atherosclerosis or HIV-related immunosuppression. Further studies are needed to evaluate whether PR contributes to higher rates of MI in HIV+ individuals.

HIV infection is associated with an increased prevalence of coronary noncalcified plaque among participants with a coronary artery calcium score of zero: Multicenter AIDS Cohort Study (MACS)

OBJECTIVES

HIV-infected individuals bear increased cardiovascular risk even in the absence of traditional cardiovascular risk factors. In the general population, coronary artery calcium (CAC) scanning is of value for cardiovascular risk stratification, but whether a CAC score of zero implies a low noncalcified coronary plaque burden in HIV-infected persons is unknown.

METHODS

We assessed the prevalence of noncalcified coronary plaque and compared noncalcified coronary plaque burden between HIV-infected and HIV-uninfected participants who had CAC scores of zero in the Multicenter AIDS Cohort Study (MACS) using coronary computed tomography (CT) angiography.

RESULTS

HIV infection was associated with the presence of noncalcified coronary plaque among these men with CAC scores of zero. In a model adjusted only for age, race, centre, and pre- or post-2001 cohort, the prevalence ratio for the presence of noncalcified plaque was 1.27 (95% confidence interval 1.04-1.56; P = 0.02). After additionally adjusting for cardiovascular risk factors, HIV infection remained associated with the presence of noncalcified coronary plaque (prevalence ratio 1.31; 95% confidence interval 1.07-1.6; P = 0.01).

CONCLUSIONS

Among men with CAC scores of zero, HIV infection is associated with an increased prevalence of noncalcified coronary plaque independent of traditional cardiovascular risk factors. This finding suggests that CAC scanning may underestimate plaque burden in HIV-infected men.

Adiponectin and interleukin-6, but not adipose tissue, are associated with worse neurocognitive function in HIV-infected men

BACKGROUND

Generalized obesity has been associated with cognitive decline, a process potentially mediated by adipocytokines. The effects of regional adipose tissue (AT) on cognition, however, are not well understood. We explored cross-sectional relationships between regional AT, adipocytokines, inflammatory markers and neuropsychological (NP) test scores among HIV+ and HIV- men enrolled in the Multicenter AIDS Cohort Study.

METHODS

Visceral, subcutaneous abdominal and subcutaneous thigh AT areas were quantified by computed tomography (CT). NP tests (Trail Making Test parts A and B, and Symbol-Digit Modalities) obtained within 2 years of CT screened for psychomotor speed and executive function. Adiponectin, leptin, interleukin-6 (IL-6) and high-sensitivity C-reactive protein (hs-CRP) were measured.

RESULTS

Of 509 HIV+ and 271 HIV- participants, HIV+ men (98% on antiretroviral therapy, 81% HIV-1 RNA<50 copies/ml) had lower median subcutaneous AT and adiponectin levels and higher hs-CRP levels, but visceral AT, body mass index, IL-6 and NP scores did not vary by HIV serostatus. In multivariable analysis, older age, ≤ high school education and African American race, but not AT area or site, were associated with worse NP test scores among all participants. In HIV+ only, higher adiponectin and IL-6 were associated with worse cognitive function independent of AT area. No HIV-specific factors were associated with NP test scores.

CONCLUSIONS

Demographic factors were associated with NP test performance, but regional adiposity was not. In HIV+ only, higher adiponectin and IL-6 were associated with worse NP test scores, supporting a role for chronic inflammation and adipocytokine imbalance in neurocognitive decline in HIV+ persons.

Elevated levels of monocyte activation markers are associated with subclinical atherosclerosis in men with and those without HIV infection

BACKGROUND

Heightened immune activation among human immunodeficiency virus (HIV)-infected persons may contribute to atherosclerosis. We assessed associations of serologic markers of monocyte activation, soluble CD163 (sCD163) and soluble CD14 (sCD14), and monocyte chemoattractant protein 1 (CCL2) with subclinical atherosclerosis among men with and those without HIV infection in the Multicenter AIDS Cohort Study.

METHODS

We performed noncontrast computed tomography on 906 men (566 HIV-infected men and 340 HIV-uninfected men), 709 of whom also underwent coronary computed tomographic angiography. Associations between each biomarker and the prevalence of coronary plaque, the prevalence of stenosis of ≥50%, and the extent of plaque were assessed by logistic and linear regression, adjusting for age, race, HIV serostatus, and cardiovascular risk factors.

RESULTS

Levels of all biomarkers were higher among HIV-infected men, of whom 81% had undetectable HIV RNA, and were associated with lower CD4(+) T-cell counts. In the entire population and among HIV-infected men, higher biomarker levels were associated with a greater prevalence of coronary artery stenosis of ≥50%. Higher sCD163 levels were also associated with greater prevalences of coronary artery calcium, mixed plaque, and calcified plaque; higher CCL2 levels were associated with a greater extent of noncalcified plaque.

CONCLUSIONS

sCD163, sCD14, and CCL2 levels were elevated in treated HIV-infected men and associated with atherosclerosis. Monocyte activation may increase the risk for cardiovascular disease in individuals with HIV infection.

Comparison of racial differences in plaque composition and stenosis between HIV-positive and HIV-negative men from the Multicenter AIDS Cohort Study

Previous studies demonstrated that blacks have less coronary artery calcification (CAC) than whites. We evaluated racial differences in plaque composition and stenosis in the Multicenter AIDS Cohort Study. HIV-positive and HIV-negative men underwent noncontrast cardiac computed tomography (CT) if they were aged 40 to 70 years, weighed <136 kg, and had no history of cardiac surgery or revascularization and, if eligible, coronary CT angiography (CTA). There were 1,001 men who underwent CT scans and 759 men CTA. We measured CAC on noncontrast CT and identified total plaque, noncalcified plaque, calcified plaque, mixed plaque, and coronary stenosis >50% on CTA. The association of presence and extent of plaque with race was determined after adjustment for HIV serostatus, cardiovascular risk factors, and measures of socioeconomic status. The prevalences of any plaque on CTA and noncalcified plaque were not different between black and white men; however, black men had lower prevalences of CAC (prevalence ratio [PR] 0.79, p = 0.01), calcified plaque (PR 0.69, p = 0.002), and stenosis >50% (PR 0.59, p = 0.009). There were no associations between black race and extent of plaque in fully adjusted models. Using log-linear regression, black race was associated with a lower extent of any plaque on CTA in HIV-positive men (estimate = -0.24, p = 0.051) but not in HIV-negative men (0.12, p = 0.50, HIV interaction p = 0.005). In conclusion, a lower prevalence of CAC in black compared with white men appears to reflect less calcification of plaque and stenosis rather than a lower overall prevalence of plaque.

Epicardial fat is associated with duration of antiretroviral therapy and coronary atherosclerosis

OBJECTIVE

Cytokines released by epicardial fat are implicated in the pathogenesis of atherosclerosis. HIV infection and antiretroviral therapy have been associated with changes in body fat distribution and coronary artery disease. We sought to determine whether HIV infection is associated with greater epicardial fat and whether epicardial fat is associated with subclinical coronary atherosclerosis.

DESIGN

We studied 579 HIV-infected and 353 HIV-uninfected men aged 40-70 years with noncontrast computed tomography to measure epicardial adipose tissue (EAT) volume and coronary artery calcium (CAC). Total plaque score (TPS) and plaque subtypes (noncalcified, calcified, and mixed) were measured by coronary computed tomography angiography in 706 men.

METHODS

We evaluated the association between EAT and HIV serostatus, and the association of EAT with subclinical atherosclerosis, adjusting for age, race, and serostatus and with additional cardiovascular risk factors and tested for modifying effects of HIV serostatus.

RESULTS

HIV-infected men had greater EAT than HIV-uninfected men (P=0.001). EAT was positively associated with duration of antiretroviral therapy (P=0.02), specifically azidothymidine (P<0.05). EAT was associated with presence of any coronary artery plaque (P=0.006) and noncalcified plaque (P=0.001), adjusting for age, race, serostatus, and cardiovascular risk factors. Among men with CAC, EAT was associated with CAC extent (P=0.006). HIV serostatus did not modify associations between EAT and either CAC extent or presence of plaque.

CONCLUSION

Greater epicardial fat volume in HIV-infected men and its association with coronary plaque and antiretroviral therapy duration suggest potential mechanisms that might lead to increased risk for cardiovascular disease in HIV.

Associations between HIV infection and subclinical coronary atherosclerosis

BACKGROUND

Coronary artery disease (CAD) has been associated with HIV infection, but data are not consistent.

OBJECTIVE

To determine whether HIV-infected men have more coronary atherosclerosis than uninfected men.

DESIGN

Cross-sectional study.

SETTING

Multicenter AIDS Cohort Study.

PARTICIPANTS

HIV-infected (n = 618) and uninfected (n = 383) men who have sex with men who were aged 40 to 70 years, weighed less than 136 kg (200 lb), and had no history of coronary revascularization.

MEASUREMENTS

Presence and extent of coronary artery calcium (CAC) on noncontrast cardiac computed tomography (CT) and of any plaque; noncalcified, mixed, or calcified plaque; or stenosis on coronary CT angiography.

RESULTS

1001 men had noncontrast CT, of whom 759 had coronary CT angiography. After adjustment for age, race, CT scanning center, and cohort, HIV-infected men had a greater prevalence of CAC (prevalence ratio [PR], 1.21 [95% CI, 1.08 to 1.35]; P = 0.001) and any plaque (PR, 1.14 [CI, 1.05 to 1.24]; P = 0.001), including noncalcified (PR, 1.28 [CI, 1.13 to 1.45]; P < 0.001) and mixed (PR, 1.35 [CI, 1.10 to 1.65]; P = 0.004) plaque, than uninfected men. Associations between HIV infection and any plaque or noncalcified plaque remained significant (P < 0.005) after CAD risk factor adjustment. HIV-infected men had a greater extent of noncalcified plaque after CAD risk factor adjustment (P = 0.026). They also had a greater prevalence of coronary artery stenosis greater than 50% (PR, 1.48 [CI, 1.06 to 2.07]; P = 0.020), but not after CAD risk factor adjustment. Longer duration of highly active antiretroviral therapy (PR, 1.09 [CI, 1.02 to 1.17]; P = 0.007) and lower nadir CD4+ T-cell count (PR, 0.80 [CI, 0.69 to 0.94]; P = 0.005) were associated with coronary stenosis greater than 50%.

LIMITATION

Cross-sectional observational study design and inclusion of only men.

CONCLUSION

Coronary artery plaque, especially noncalcified plaque, is more prevalent and extensive in HIV-infected men, independent of CAD risk factors.

PRIMARY FUNDING SOURCE

National Heart, Lung, and Blood Institute and National Institute of Allergy and Infectious Diseases.

Lower adiponectin is associated with subclinical cardiovascular disease among HIV-infected men

OBJECTIVE

To examine whether altered levels of adipokines, adipose-derived peptides associated with myocardial infarction in the general population, may contribute to subclinical coronary atherosclerosis in HIV-infected persons.

DESIGN

Nested cohort study.

METHODS

We studied HIV-infected (HIV+) and HIV-uninfected (HIV-) men in the Multicenter AIDS Cohort Study with noncontrast computed tomography (CT) to measure coronary artery calcium and regional adiposity; 75% additionally underwent coronary CT angiography to measure plaque composition and stenosis. Adiponectin and leptin levels were assessed. Multiple regression models were used to assess associations between adipokine levels and HIV disease parameters, regional adiposity, and plaque adjusted for age, race, HIV serostatus, and cardiovascular disease (CVD) risk factors.

RESULTS

Significant findings were limited to adiponectin. HIV-positive men (n=493) had lower adiponectin levels than HIV-negative men (n=250) after adjusting for CVD risk factors (P<0.0001), which became nonsignificant after adjustment for abdominal visceral and thigh subcutaneous adipose tissue. Among HIV-positive men, lower adiponectin levels were associated with higher CD4 T-cell counts (P=0.004), longer duration of antiretroviral therapy (P=0.006), and undetectable HIV RNA levels (P=0.04) after adjusting for age, race, and CVD risk factors; only CD4 cell count remained significant after further adjustment for adipose tissue. In both groups, lower adiponectin levels were associated with increased odds of coronary stenosis more than 50% (P<0.007). Lower adiponectin levels were associated with increased extent of plaque in HIV-positive and of mixed plaque in HIV-negative men.

CONCLUSION

Adiponectin levels were lower in HIV-infected men and related to the severity of subclinical atherosclerosis, independent of traditional CVD risk factors.