An updated prediction model of the global risk of cardiovascular disease in HIV-positive persons: The Data-collection on Adverse Effects of Anti-HIV Drugs (D:A:D) study

Ideal Cardiovascular Health and Carotid Atherosclerosis in a Mixed Cohort of HIV-Infected and Uninfected Ugandans

Preventable cardiovascular disease (CVD) risk factors are responsible for the majority of CVD-related deaths, and are increasingly recognized as a cause of morbidity and mortality for HIV-infected persons taking antiretroviral therapy (ART). Simplified tools such as the American Heart Association's ideal cardiovascular health (iCVH) construct may identify and prognosticate CVD risk in resource-limited settings. No studies have evaluated iCVH metrics in sub-Saharan Africa or among HIV-infected adults. Thus, the central aim of this study was to compare levels of iCVH metrics and their correlations with carotid atherosclerosis for HIV-infected adults versus uninfected controls in a well-phenotyped Ugandan cohort. We analyzed the prevalence of iCVH metrics in a mixed cohort of HIV-infected persons on stable ART and uninfected, population-based comparators in Mbarara, Uganda. We also assessed the validity of iCVH by correlating iCVH values with common carotid intima media thickness (CCIMT). HIV-infected persons had a mean of 4.9 (SD 1.1) iCVH metrics at ideal levels versus 4.3 (SD 1.2) for uninfected controls (p = .002). This difference was largely driven by differences in blood pressure, blood glucose, and diet. In multivariable-adjusted linear regression models, each additional iCVH metric at an ideal level was associated with a significant 0.024 mm decrease in CCIMT (p < .001).HIV-infected persons on ART in rural Uganda had more iCVH metrics at ideal levels than uninfected persons. The difference appeared driven by factors that are putatively influenced by access to routine medical care. Composite scores of iCVH metrics were associated with subclinical atherosclerosis and more predictive of atherosclerosis for uninfected persons.

Lipid-lowering effect and changes in estimated cardiovascular risk after switching to a tenofovir-containing regimen for the treatment of HIV-infected patients

Tenofovir could have a direct lipid-lowering effect. The aim of our retrospective study was to investigate changes in cardiovascular risk after switching from a tenofovir-sparing to a tenofovir-containing backbone. Lipid parameters and cardiovascular risk [calculated using 10-years Framingham Risk Score (FRS) and 5-years DAD Risk Score (DRS)] were analysed at baseline and after three months. 273 patients were enrolled. After switching, significant decreases in total cholesterol (TC) (-8.2mg/dl, p < 0.001), LDL (-8.7mg/dl, p < 0.001) and DRS (mean -0.26%, p < 0.001) were observed, while a reduction in FRS was only observed in patients with pre-switch high TC or medium-high (>10%) FRS. Pre-switch factors associated with DRS reduction were higher TC, abacavir, new generation protease inhibitors, while zidovudine predicted an increase of DRS. Our results suggest that the improvement of lipid parameters observed after switching to a tenofovir-containing backbone could lead to a significant reduction in predicted cardiovascular risk, which became more evident in subjects with higher cardiovascular risk.

White matter hyperintensities in relation to cognition in HIV-infected men with sustained suppressed viral load on combination antiretroviral therapy

OBJECTIVES

The objective of this study was to assess whether HIV-infected patients on long-term successful combination antiretroviral therapy (cART) have more extensive white matter hyperintensities (WMH) of presumed vascular origin compared with uninfected controls and whether these intensities are associated with cognitive impairment. Furthermore, we explored potential determinants of increased WMH load long-term suppressed HIV infection.

DESIGN

A cross-sectional comparison of WMH in an observational cohort.

METHODS

Clinical, cognitive, and MRI data were collected from 103 middle-aged, aviremic HIV-infected men on cART, and 70 HIV-uninfected, otherwise similar controls. In the MRI data, WMH load was quantified by automated approaches and qualitatively reviewed by an experienced neuroradiologist using the Fazekas scale.

RESULTS

HIV-infected men had an increased WMH load. Among HIV-infected patients, increased WMH load was independently associated with older age, higher DBP, higher D-dimer levels, and longer time spent with a CD4 cell count below 500 cells/μl. HIV-associated cognitive deficits were associated with increased WMH load.

CONCLUSIONS

WMH are more extensive and associated with cognitive deficits in middle-aged, aviremic cART-treated HIV-infected men. The extent of WMH load was associated with both cardiovascular risk factors and past immune deficiency. As cognitive impairment in these same patients is also associated with these risk factors, this may suggest that in the setting of HIV, WMH, and cognitive deficits share a common cause. This supports the importance of optimizing cardiovascular risk management, and early, effective treatment of HIV infection.

Cardiovascular Disease Risk Prediction in the HIV Outpatient Study

BACKGROUND

 Cardiovascular disease (CVD) risk prediction tools are often applied to populations beyond those in which they were designed when validated tools for specific subpopulations are unavailable.

METHODS

 Using data from 2283 human immunodeficiency virus (HIV)-infected adults aged ≥18 years, who were active in the HIV Outpatient Study (HOPS), we assessed performance of 3 commonly used CVD prediction models developed for general populations: Framingham general cardiovascular Risk Score (FRS), American College of Cardiology/American Heart Association Pooled Cohort equations (PCEs), and Systematic COronary Risk Evaluation (SCORE) high-risk equation, and 1 model developed in HIV-infected persons: the Data Collection on Adverse Effects of Anti-HIV Drugs (D:A:D) study equation. C-statistics assessed model discrimination and the ratio of expected to observed events (E/O) and Hosmer-Lemeshow χ² P value assessed calibration.

RESULTS

 From January 2002 through September 2013, 195 (8.5%) HOPS participants experienced an incident CVD event in 15 056 person-years. The FRS demonstrated moderate discrimination and was well calibrated (C-statistic: 0.66, E/O: 1.01, P = .89). The PCE and D:A:D risk equations demonstrated good discrimination but were less well calibrated (C-statistics: 0.71 and 0.72 and E/O: 0.88 and 0.80, respectively; P < .001 for both), whereas SCORE performed poorly (C-statistic: 0.59, E/O: 1.72; P = .48).

CONCLUSIONS

 Only the FRS accurately estimated risk of CVD events, while PCE and D:A:D underestimated risk. Although these models could potentially be used to rank US HIV-infected individuals at higher or lower risk for CVD, the models may fail to identify substantial numbers of HIV-infected persons with elevated CVD risk who could potentially benefit from additional medical treatment.

Prediction of hard cardiovascular events in HIV patients

OBJECTIVES

To assess the accuracy of risk prediction algorithms used in the general population and an HIV-specific algorithm to predict hard cardiovascular events.

METHODS

We compared the pooled equation algorithm (PE) proposed by the American Heart Association with the Framingham risk score (FRS) and the HIV-specific DAD (Data Collection on Adverse Effects of Anti-HIV Drugs) algorithm in a cohort of 2550 HIV+ patients followed for 17 337 patient-years.

RESULTS

During follow-up we recorded 67 myocardial infarctions and 2 cardiovascular deaths. PE and FRS identified and missed the same number of events (44 of 69 identified by PE and 49 of 69 by FRS). Similarly, DAD and FRS predicted and missed the same number of events (38 of 64 and 44 of 64 identified, respectively). All algorithms showed moderate sensitivity, specificity and positive predictive values, but high negative predictive values. However, PE and DAD identified more patients with no events than FRS (13.8% and 9.3% net reclassification improvement, respectively).

CONCLUSIONS

All algorithms showed a modest predictive ability, although the PE and DAD algorithms identified more patients at low risk.

Risk of Cardiovascular Disease in an Aging HIV Population: Where Are We Now?

With more effective and widespread antiretroviral treatment, the overall incidence of AIDS- or HIV-related death has decreased dramatically. Consequently, as patients are aging, cardiovascular disease (CVD) has emerged as an important cause of morbidity and mortality in the HIV population. The incidence of CVD overall in HIV is relatively low, but it is approximately 1.5-2-fold higher than that seen in age-matched HIV-uninfected individuals. Multiple factors are believed to explain this excess in risk such as overrepresentation of traditional cardiovascular risk factors (particularly smoking), toxicities associated with cumulative exposure to some antiretroviral agents, together with persistent chronic inflammation, and immune activation associated with HIV infection. Tools are available to calculate an individual's predicted risk of CVD and should be incorporated in the regular follow-up of HIV-infected patients. Targeted interventions to reduce this risk must be recommended, including life-style changes and medical interventions that might include changes in antiretroviral therapy.

Baseline, Time-Updated, and Cumulative HIV Care Metrics for Predicting Acute Myocardial Infarction and All-Cause Mortality

BACKGROUND

 After adjustment for cardiovascular risk factors and despite higher mortality, those with human immunodeficiency virus (HIV+) have a greater risk of acute myocardial infarction (AMI) than uninfected individuals.

METHODS

 We included HIV+ individuals who started combination antiretroviral therapy (cART) in the Veterans Aging Cohort Study (VACS) from 1996 to 2012. We fit multivariable proportional hazards models for baseline, time-updated and cumulative measures of HIV-1 RNA, CD4 counts, and the VACS Index. We used the trapezoidal rule to build the following cumulative measures: viremia copy-years, CD4-years, and VACS Index score-years, captured 180 days after cART initiation until AMI, death, last clinic visit, or 30 September 2012. The primary outcomes were incident AMI (Medicaid, Medicare, and Veterans Affairs International Classification of Diseases-9 codes) and death.

RESULTS

 A total of 8168 HIV+ individuals (53 861 person-years) were analyzed with 196 incident AMIs and 1710 deaths. Controlling for known cardiovascular risk factors, 6 of the 9 metrics predicted AMI and all metrics predicted mortality. Time-updated VACS Index had the lowest Akaike information criterion among all models for both outcomes. A time-updated VACS Index score of 55+ was associated with a hazard ratio (HR) of 3.31 (95% confidence interval [CI], 2.11-5.20) for AMI and a HR of 31.77 (95% CI, 26.17-38.57) for mortality.

CONCLUSIONS

 Time-updated VACS Index provided better AMI and mortality prediction than CD4 count and HIV-1 RNA, suggesting that current health determines risk more accurately than prior history and that risk assessment can be improved by biomarkers of organ injury.

Renal Impairment and Cardiovascular Disease in HIV-Positive Individuals: The D:A:D Study

BACKGROUND

While the association between renal impairment and cardiovascular disease (CVD) is well established in the general population, the association remains poorly understood in human immunodeficiency virus (HIV)-positive individuals.

METHODS

Individuals with ≥2 estimated glomerular filtration rate (eGFR) measurements after 1 February 2004 were followed until CVD, death, last visit plus 6 months, or 1 February 2015. CVD was defined as the occurrence of centrally validated myocardial infarction, stroke, invasive cardiovascular procedures, or sudden cardiac death.

RESULTS

During a median follow-up duration of 8.0 years (interquartile range, 5.4-8.9 years) 1357 of 35 357 individuals developed CVD (incidence rate, 5.2 cases/1000 person-years [95% confidence interval {CI}, 5.0-5.5]). Confirmed baseline eGFR and CVD were closely related with 1.8% of individuals (95% CI, 1.6%-2.0%) with an eGFR > 90 mL/minute/1.73 m(2) estimated to develop CVD at 5 years, increasing to 21.1% (95% CI, 6.6%-35.6%) among those with an eGFR ≤ 30 mL/minute/1.73 m(2) The strong univariate relationship between low current eGFR and CVD was primarily explained by increasing age in adjusted analyses, although all eGFRs ≤ 80 mL/minute/1.73 m(2) remained associated with 30%-40% increased CVD rates, and particularly high CVD rates among individuals with an eGFR ≤ 30 mL/minute/1.73 m(2) (incidence rate ratio, 3.08 [95% CI, 2.04-4.65]).

CONCLUSIONS

Among HIV-positive individuals in a large contemporary cohort, a strong relation between confirmed impaired eGFR and CVD was observed. This finding highlights the need for renal preventive measures and intensified monitoring for emerging CVD, particularly in older individuals with continuously low eGFRs.

Vascular age calculation and equivalent risk factors in HIV-infected patients obtained from the D:A:D risk equation

BACKGROUND

Vascular age is a concept that represents the hypothetical age of the cardiovascular system and might be an alternative way of expressing the cardiovascular risk of a patient. The Data Collection on Adverse Effects of Anti-HIV Drugs Study (D:A:D) developed a cardiovascular risk equation from a population of HIV-infected patients, incorporating exposure to individual antiretroviral therapy drugs and traditional classic cardiovascular risk factors.

OBJECTIVES

The aim of this study was to determine the vascular age calculated from the D:A:D equation, for HIV infected patients.

METHODS

Vascular age was calculated according to its definition by using the D:A:D equation. The Poisson regression model used in the D:A:D equation is an exponential model to calculate the vascular age to match the exponent of the equation with the factors of a patient with the exponent of a subject with controlled risk factors.

RESULTS

We obtained an equation that allows calculating the vascular age of a patient considering cardiovascular risk factors listed in the same D:A:D equation. From the equation, we have built a table for easy calculation of the vascular age and a table of cardiovascular risk equivalents.

CONCLUSIONS

Vascular age is a new concept derived from Framingham risk tables that can be calculated with other risk scales, such as D:A:D for HIV patients. The calculation of vascular age in HIV patients could be a useful tool for communicating cardiovascular risk and to improve the control of modifiable risk factors.

Heart aging measured with coronary artery calcium scoring and cardiovascular risk assessment algorithms in HIV infected patients

ABTRACT Many sources have highlighted the high incidence of premature cardiovascular events in HIV infected patients. This raises the suspicion of an accelerated aging of the vascular system in this disease characterized by chronic systemic subliminal inflammation and immune dysregulation. Unfortunately all currently available risk assessment algorithms based on traditional risk factors, and even those containing more HIV-specific factors, fail to accurately predict risk in a large proportion of patients. In the general population several models have implemented imaging data to refine risk assessment, and the concept of vascular aging has been of value in improving the performance of these algorithms. It is expected that HIV patients may benefit from a similar approach as it becomes clearer that vascular imaging provides valuable prognostic information in this patient category.

Pathophysiology and management of cardiovascular disease in patients with HIV

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

Effects of once-daily darunavir/ritonavir versus atazanavir/ritonavir on insulin sensitivity in HIV-infected persons over 48 weeks: results of an exploratory substudy of METABOLIK, a phase 4, randomized trial

Background: The phase 4, METABOLIK trial demonstrated that changes in metabolic parameters with darunavir with low-dose ritonavir (DRV/r) were comparable to those observed with atazanavir with low-dose ritonavir (ATV/r). A comprehensive assessment of the effects of these agents on insulin sensitivity will provide additional, relevant clinical information.

Methods: In this substudy of METABOLIK, HIV-1–infected, antiretroviral agent–naïve male subjects aged ≥18 years with a viral load of >1,000 copies/mL were randomized to receive DRV/r 800/100 mg once daily (qd) or ATV/r 300/100 mg qd, both with a fixed dose of tenofovir disoproxil fumarate/emtricitabine 300/200 mg qd. The effects of DRV/r versus ATV/r on insulin sensitivity over 48 weeks were compared using the euglycemic hyperinsulinemic clamp, the preferred method to assess insulin sensitivity; primary end point was the effect on insulin sensitivity during the first 12 weeks.

Results: Twenty-seven subjects completed the study. In the DRV/r arm (n = 14), median glucose disposal from baseline through weeks 12 and 48 was 9.3, 11.4, and 9.9 mg/kg*min, respectively; in the ATV/r arm (n = 13), these values were 8.9, 8.6, and 9.1 mg/kg*min, respectively. Median insulin sensitivity in the DRV/r arm at baseline, week 12, and week 48 was 24.0, 25.0, and 21.5 mg/kg*min per μIU/mL × 100, respectively; these values in the ATV/r arm were 20.7, 22.0, and 22.0 mg/kg*min per μIU/mL × 100, respectively. Most subjects had ≥1 adverse event, including three serious adverse events (n = 2 [DRV/r], n = 1 [ATV/r]).

Conclusions: DRV/r and ATV/r displayed similar modest effects on insulin sensitivity using a euglycemic hyperinsulinemic clamp.

Hypertension Is a Key Feature of the Metabolic Syndrome in Subjects Aging with HIV

With widespread and effective antiretroviral therapy, the life expectancy in the HIV population has dramatically improved over the last two decades. Consequently, as patients are aging with HIV, other age-related comorbidities, such as metabolic disturbances and cardiovascular disease (CVD), have emerged as important causes of morbidity and mortality. An overrepresentation of traditional cardiovascular risk factors (RF), toxicities associated with long exposure to antiretroviral therapy, together with residual chronic inflammation and immune activation associated with HIV infection are thought to predispose to these metabolic complications and to the excess risk of CVD observed in the HIV population. The metabolic syndrome (MS) represents a clustering of RF for CVD that includes abdominal obesity, hypertension, dyslipidemia and insulin resistance. Hypertension is a prevalent feature of the MS in HIV, in particular in the aging population, and constitutes an important RF for CVD. Physicians should screen their patients for metabolic and cardiovascular risk at the regular visits to reduce MS and the associated CVD risk among people aging with HIV, since many of RF are under-diagnosed and under-treated conditions. Interventions to reduce these RF can include lifestyle changes and pharmacological interventions such as antihypertensive and lipid-lowering therapy, and treatment of glucose metabolism disturbances. Changes in antiretroviral therapy to more metabolic neutral antiretroviral drugs may also be considered.

Neutrophil to Lymphocyte Ratio and Cardiovascular Disease Incidence in HIV-Infected Patients: A Population-Based Cohort Study

Neutrophil to lymphocyte ratio (NLR) has been shown to predict occurrence of cardiovascular events in the general population. The aim of our study was to evaluate the role of NLR to predict major cardiovascular disease (CVD) events in HIV-infected subjects. We performed a retrospective cohort study of HIV-infected patients residing in the Local Health Authority (LHA) of Brescia, northern Italy, from 2000 to 2012. The incidence of CVD events in HIV-positive patients was compared with that expected in the general population living in the same area, computing standardized incidence ratios (SIRs). To evaluate the predictive role of NLR, univariate and multivariate Cox regression models were applied, computing hazard ratios (HRs). A total of 3766 HIV-infected patients (mean age 38.1 years, 71.3% males) were included (person-years 28768.6). A total of 134 CVD events occurred in 119 HIV-infected patients. A 2-fold increased risk (SIR 2.02) of CVD was found in HIV-infected patients compared to the general population. NLR levels measured at baseline and during follow-up were independently associated with CVD incidence, when also adjusting for both traditional CVD risk factors and HIV-related factors (HR 3.05 for NLR≥ 1.2). The area under the receiver operating characteristics (ROC) curve showed a modest, not statistically significant, increase, from 0.81 to 0.83, with addition of NLR to Framingham risk score model covariates. In conclusion an elevated NLR is a predictor of risk CVD in HIV-infected patients, independently from the traditional CVD risk factors.

Cancer prevention in HIV-infected populations

People living with human immunodeficiency virus (HIV) are living longer since the advent of effective combined antiretroviral therapy (cART). While cART substantially decreases the risk of developing some cancers, HIV-infected individuals remain at high risk for Kaposi sarcoma, lymphoma, and several solid tumors. Currently HIV-infected patients represent an aging group, and malignancies have become a leading cause of morbidity and mortality. Tailored cancer-prevention strategies are needed for this population. In this review we describe the etiologic agents and pathogenesis of common malignancies in the setting of HIV, as well as current evidence for cancer prevention strategies and screening programs.