Relationship between hepatitis C virus (HCV) and insulin resistance, endothelial perturbation, and platelet activation in HIV-HCV-coinfected patients under highly active antiretroviral treatment

Endothelial dysfunction, a predictor of cardiovascular disease in HIV patients on antiretroviral therapy: A systematic review and meta-analysis

Aim Although antiretroviral therapy (ART) is available, the rate of new HIV infections is alarming. With this trend, it is anticipated that the use of ART will continue to rise, potentially resulting in associated vascular disorders. Therefore, we aimed to examine the impact of ART on endothelial function in people living with HIV (PLHIV), a predictor of cardiovascular diseases.

METHOD

A comprehensive search for evidence was made on PubMed and Scopus on May 06, 2023, following the Preferred Reporting Items for Systematic Review and Meta-analysis. Cochrane and Newcastle-Ottawa quality assessment scales were used to evaluate quality, while the metaHun web tool and Review Manager version 5.4.1 were used for analysis. Subgroup, sensitivity, and publication bias were conducted for each outcome measure.

RESULTS

We identified 37 studies, including a sample size of 3700 with 2265 individuals on ART. The analyzed evidence showed a large significant effect of ART on vascular cell adhesion molecule-1, with a standardized mean difference (SMD) of -1.23 (95 % CI: -1.72, -0.74; p = 0.0013). Similarly, a significant medium effect of ART was observed on intercellular cell adhesion molecule-1 in PLHIV, with an SMD of -1.28 (95 % CI: -2.00, -0.56; p = 0.0231) compared to the control group. Furthermore, ART exhibited a significant but small effect on flow-mediated dilation (FMD) with an SMD of -0.40 (95 % CI: -0.62, -0.19, p = 0.0159).

CONCLUSION

Our findings show an improved endothelial function in PLHIV on ART, as demonstrated by reduced adhesion molecules; however, ART exhibited a small effect on FMD, thus suggesting PLHIV on ART may still be at risk of endothelial dysfunction and further cardiovascular diseases.

Selected inflammatory and coagulation biomarkers pre-viral suppression in people with human immunodeficiency virus (HIV) infection without overt cardiovascular disease: Is there a need to redefine reference indices?

BACKGROUND

Human immunodeficiency virus (HIV) infection is prevalent in Africa and causes morbidity and mortality despite antiretroviral therapy (ART). Non-communicable complications of HIV infection include cardiovascular disease (CVD) with thromboses throughout the vascular tree. Ongoing inflammation and endothelial dysfunction in people living with HIV (PLWH) probably contribute significantly to HIV-related CVD.

OBJECTIVES

A systematic review was conducted to inform interpretation of 5 biomarkers commonly measured in PLWH namely interleukin-6 (IL-6), tumour necrosis factor alpha (TNF-α), D-dimers, and soluble intracellular and vascular adhesion molecules-1 (sICAM-1 and sVCAM-1) to attempt to define a range for these values in ART naïve PLWH without overt CVD or additional comorbid diseases.

METHODS

A systematic search was conducted for all studies documenting the levels of the above biomarkers in ART naïve PLWH published on the PubMed database from 1994 to 2020.

RESULTS

The number of publications that reported medians above the assay values was: 4/15 for D-dimer; 0/5 for TNF-α, 8/16 for IL-6, 3/6 for sVCAM-1, and 4/5 for sICAM-1.

CONCLUSION

The clinical utility of biomarkers is reduced by the lack of standardisation of the measurement of these parameters, absence of normal reference indices and the lack of uniformity of study protocols in different research centres. This review supports the ongoing use of D-dimers to predict thrombotic and bleeding events in PLWH since the weighted averages across study assays suggest that the median levels do not exceed the reference range. The role of inflammatory cytokine monitoring and measurement of endothelial adhesion markers is less clear.

Platelet activation in adult HIV-infected patients on antiretroviral therapy: a systematic review and meta-analysis

BACKGROUND

Antiretroviral therapy (ART) alters platelet reactivity, and as a consequence, patients living with HIV may be at an increased risk of cardiovascular disease (CVD). The current evidence on platelet activation levels in patients with HIV remains inconclusive. We therefore aimed to systematically synthesise evidence on the association of platelet activation in HIV-infected patients on successful treatment.

METHODS

Electronic databases were searched from inception until November 2019. Studies were included if the primary or secondary outcome of the study was to assess platelet activation in HIV-infected patients on ART. The primary outcome of this review included the levels of platelet activation. The pooled effect estimates were calculated using a random-effects meta-analysis model.

RESULTS

We identified 30 studies comprising of 2325 participants. The pooled estimates showed elevated levels of platelet activation in treatment-naïve HIV-infected patients compared to uninfected controls (Hedges' g 2.00 [95%CI 1.05, 2.94]; z = 4.12, p < 0.0001). These remained elevated despite successful ART (Hedges' g 2.05 [95%CI 0.58, 3.52]; z = 2.71, p = 0.0067).

CONCLUSION

The levels of platelet activation are elevated in treatment-naïve HIV-infected patients, and these persist during successful ART. Further studies should assess the clinical relevance of monitoring the levels of platelet activation in HIV-infected patients on ART.

Liver Stiffness Hinders Normalization of Systemic Inflammation and Endothelial Activation after Hepatitis C Virus (HCV) Eradication in HIV/HCV Coinfected Patients

Systemic inflammation, endothelial dysfunction and coagulopathy are of high clinical relevance in the management of people living with HIV (PLWH), and even more in patients coinfected with hepatitis C virus (HCV). It has been suggested a significant impact of HCV coinfection on these conditions. However, HCV can be eradicated in most patients with the new direct-acting antivirals (DAAs) therapy. We have analyzed the effect of HCV on systemic inflammation, endothelial activation and coagulopathy in PLWH and its evolution after HCV eradication with DAAs. Twenty-five HIV/HCV coinfected (HIV/HCV group), 25 HIV monoinfected (HIV group) and 20 healthy controls (HC) were included in the study. All patients were on ART and HIV suppressed. Levels of fourteen markers of systemic inflammation, endothelial activation and coagulopathy (IL-1ß, IL-6, IL-12p70, IL-8, TNFα, D-dimer, Eotaxin, IL-18, IP-10, monocyte chemotactic protein-1 (MCP-1), plasminogen activator inhibitor-1 (PAI-1), TNFα receptor 1 (TNFR1), vascular cell adhesion molecule 1 (VCAM-1) and intercellular adhesion molecule 1 (ICAM-1)) were measured on plasma at baseline and after DAAs-mediated HCV eradication. Non-parametric tests were used to establish inter/intra-group differences. At baseline, the HIV/HCV group showed increased levels of IL-18 (p = 0.028), IP-10 (p < 0.0001), VCAM-1 (p < 0.0001) and ICAM-1 (p = 0.045), compared to the HC and HIV groups, with the highest levels for IL18 and IP10 observed in HIV/HCV patients with increased liver stiffness (≥7.1 KPa). Eradication of HCV with DAAs-based therapy restored some but not all the evaluated parameters. VCAM-1 remained significantly increased compared to HC (p = 0.001), regardless of the level of basal liver stiffness in the HIV/HCV group, and IP-10 remained significantly increased only in the HIV/HCV group, with increased level of basal liver stiffness compared to the HC and to the HIV groups (p = 0.006 and p = 0.049, respectively). These data indicate that DAAs therapy in HIV/HCV co-infected patients and HCV eradication does not always lead to the normalization of systemic inflammation and endothelial dysfunction conditions, especially in cases with increased liver stiffness.

Inflammatory and cardiovascular diseases biomarkers in chronic hepatitis C virus infection: A review

Hepatitis C virus (HCV) infects 180 million people worldwide and over 4 million people in the United States. HCV infection is a major cause of chronic liver disease and is recognized as a risk factor for clinical cardiovascular disease (CVD). Many studies have shown increased prevalence of cardiac and inflammatory biomarkers in patients with chronic HCV infection (CHC), and though these markers may be used to risk stratify people for cardiac disease in the general population their role in the HCV population is unknown. Patients with CHC have elevated cardiac and inflammatory biomarkers compared to noninfected controls which may play a role in CVD risk stratification. We undertook a systematic review of inflammatory and cardiac biomarkers in people with HCV infection with a focus on the effect of CHC on serum levels of these markers and their utility as predictors of CVD in this population. Medline, EMBASE, and Cochrane databases were searched for relevant articles until June 2019. A total of 2430 results were reviewed with 115 studies included. Our review revealed that HCV infection significantly alters serum levels of markers of inflammation, endothelial function, and cardiac dysfunction prior to HCV treatment, and some of which may change in response to HCV therapy. Current risk stratification tools for development of CVD in the general population may not account for the increased inflammatory markers that appear to be elevated among HCV‐infected patients contributing to increased CVD risk.

Metabolic and Cardiovascular Complications in HIV/HCV-Co-infected Patients

PURPOSE OF REVIEW

Fifteen to thirty percent of HIV-infected persons in North America and Europe are co-infected with chronic hepatitis C (HCV). The latter is associated with a significant number of extra-hepatic metabolic complications that could compound HIV-associated increased cardiovascular risk. This article reviews the basic science and epidemiologic and clinical evidence for increased cardio-metabolic risk among HIV/HCV-co-infected patients and discusses potential underlying mechanisms. We will finally review the impact of control of HCV viremia on the cardio-metabolic morbidity and mortality of HIV/HCV-co-infected patients.

RECENT FINDINGS

HCV infection is associated with a number of immune-related complications such as cryoglobulinemia but also metabolic complications including dyslipidemias, hepatic steatosis, insulin resistance, diabetes, and chronic kidney disease. The incidence of these complications is higher among HIV-co-infected patients and might contribute to increased mortality. The potential mechanisms of increased cardiovascular risk among HIV/HCV-co-infected subjects include endothelial dysfunction, chronic inflammation and immune activation, the cardio-metabolic effects of HCV-induced hepatic steatosis and fibrosis or insulin resistance, and chronic kidney disease. However, epidemiologic studies show discordant findings as to whether HCV co-infection further increases the risk of atherosclerotic cardiovascular diseases (acute myocardial infarctions and strokes) among HIV-infected patients. Nonetheless, successful treatment of HCV is associated with significant improvements in cardio-metabolic risk factors including diabetes mellitus. HCV co-infection is associated with a higher incidence of metabolic complications-and likely increased risk of cardiovascular events-that might contribute to increased mortality in HIV. These appear to improve with successful HCV therapy.

A systematic review of the associations between HIV/HCV coinfection and biomarkers of cardiovascular disease

The incidence of human immunodeficiency virus (HIV) and hepatitis C virus (HCV) coinfection has been increasing with over 10 million people affected globally. The role biomarkers play as predictors of cardiovascular disease (CVD) risk among coinfected individuals is not well defined. We aimed to systematically review current evidence describing CVD biomarkers among individuals with HIV/HCV coinfection. We searched EMBASE, CINAHL, Google Scholar, PubMed, and Web of Science from inception to June 2017. MeSH terms and keywords were used to identify studies with information on HIV/HCV coinfection and CVD biomarkers (structural, functional, and serological) such as carotid intima-media thickness (CIMT), endothelial markers, C-reactive protein (CRP), homocysteine, and lipids. Among 332 articles screened, 28 were included (39,498 participants). Study designs varied: 18 cross-sectional, 9 cohort, and 1 clinical trial. Compared with healthy controls and people with HIV or HCV monoinfection, individuals with HIV/HCV coinfection had statistically significant lower levels of lipids and CRP and higher levels of endothelial markers (sICAM-1 and sVCAM-1), CIMT, homocysteine, and IL-6. One study found the odds of carotid plaque in coinfected individuals was 1.64 (0.91-2.94) compared with healthy controls, and another study showed the prevalence of vascular plaques (carotid and femoral) in coinfected individuals was higher compared with HIV monoinfected individuals (44% vs 14%, P = 0.04). Biomarkers of CVD have different patterns of association with HIV/HCV coinfection compared with monoinfection and healthy controls. Prospective studies are needed to confirm the predictive value of these biomarkers for clinical CVD risk among coinfected individuals.

HIV/HCV coinfection and the risk of cardiovascular disease: A meta-analysis

The emergence of improved antiretroviral therapy has increased the life expectancy of human immunodeficiency virus (HIV)-infected individuals, although there is an increased susceptibility to developing cardiovascular diseases (CVD). The risk for CVD is purported to be even higher among people with HIV and hepatitis C virus (HCV) coinfection because of the increased inflammatory response, which may synergistically impact CVD risk. However, studies comparing CVD outcomes between HIV alone and HIV/HCV individuals have been discordant. Accordingly, we conducted a meta-analysis to clarify and quantify the association between HIV/HCV coinfection and the risk for CVD. We searched EMBASE, CINAHL, Google Scholar, PubMed, and Web of Science from inception to December 2016 to identify studies that provided information on HIV/HCV coinfection and CVD, defined as coronary artery disease, congestive heart failure and stroke. We used a random-effects model to abstract and pool data on the hazard ratios (HRs) for CVD. HRs were adjusted for traditional CVD risk factors including age, sex, smoking, hypertension, diabetes and LDL cholesterol. Among the 283 articles reviewed, four cohort studies met inclusion criteria with a total of 33 723 participants. The pooled adjusted HRs for the association between HIV/HCV coinfection and CVD were 1.24 (95% CI: 1.07-1.40) compared to HIV monoinfection. The test for heterogeneity was not statistically significant (I² =0.0%, P=.397). In conclusion, individuals with HIV/HCV coinfection had an increased CVD risk compared to those with HIV monoinfection. More research is needed to further examine the nature of this association, and response to traditional risk-reduction therapies.

Mortal allies: human immunodeficiency virus and noncommunicable diseases

PURPOSE OF REVIEW

HIV-infected individuals have improved access to antiretroviral therapy. This has resulted in a shift in causes of mortality from infectious diseases to noncommunicable diseases including cardiovascular disease, chronic kidney disease (CKD) and malignancies. This review will look at the epidemiological shift, risk factors for the development of these diseases and examine some of the supporting laboratory diagnostic testing, which may be required.

RECENT FINDINGS

Risk factors for the development of these diseases in HIV-infected patients include underlying genetic predisposition, lifestyle risk factors, chronic inflammation as a consequence of HIV infection, the presence and persistence of opportunistic infections and in some cases, highly active antiretroviral therapy, itself. Morbidity and mortality from HIV-associated conditions are increasing in low-income and middle-income countries (LMICs) with increased prevalence of HIV-associated cancers, cardiovascular disease and CKD.

SUMMARY

Management of these conditions in LMICs requires an integrated pathology solution that will enable early screening, diagnosis and monitoring.

CD4 recovery on antiretroviral therapy is associated with decreased progression to liver disease among hepatitis C virus-infected injecting drug users

Background.  Human immunodeficiency virus (HIV) coinfection accelerates liver disease progression in individuals with chronic hepatitis C. We evaluated the associations of CD4, HIV RNA, and antiretroviral therapy (ART)-induced CD4 recovery with liver diagnoses in a prospective cohort of injecting drug users (IDUs). Methods.  We evaluated 383 coinfected IDUs in the Boston area, prospectively observed for a median of 1.8 years. Liver disease progression included the first occurrence of hepatocellular carcinoma, variceal bleeding, ascites, encephalopathy, or death due to hepatic failure. Multivariable-adjusted extended Cox models were specified to estimate hazard ratios (HRs) for comparisons of CD4, change in CD4 (from nadir), and HIV RNA with respect to liver disease progression events. Results.  Twenty-four persons experienced a liver disease progression event over 1155 person-years (2.1 per 100 person-years), including 20 deaths attributed to end-stage liver disease (1.7 per 100 person-years). CD4 at baseline and over follow-up strongly predicted liver disease progression (baseline CD4 <200 vs ≥200: HR = 5.23, 95% confidence interval [CI], 2.30-11.92; time-updated CD4 <200 vs ≥200: HR = 11.79, 95% CI, 4.47-31.07). Nadir CD4 was also a strong indicator (<100 vs ≥100: HR = 3.52, 95% CI, 1.54-8.06). A lack of CD4 recovery (failure to increase 100 cells over nadir) among ART initiators was associated with increased risk (HR = 7.69; 95% CI, 2.60-22.69). Human immunodeficiency virus RNA was not significantly associated with liver disease progression. Conclusions.  Impaired immune function was highly predictive of liver disease progression in this cohort of IDUs, and a lack of CD4 recovery on ART was associated with increased risk of progression to HCV-associated liver disease.

Risk of cardiovascular disease associated with HCV and HBV coinfection among antiretroviral-treated HIV-infected individuals

BACKGROUND

The increased risk for cardiovascular disease (CVD) in HIV is well established. Despite high prevalence of viral hepatitis coinfection with HIV, there are few studies on the risk of CVD amongst antiretroviral therapy (ART)-treated coinfected patients.

METHODS

Ontario HIV Treatment Network Cohort Study participants who initiated ART without prior CVD events were analysed. HBV and HCV coinfection were identified by serology and RNA test results. CVD was defined as any of: coronary artery disease including atherosclerosis, chronic ischaemic heart disease and arteriosclerotic vascular disease; myocardial infarction; congestive heart failure; cerebrovascular accident or stroke; coronary bypass; angioplasty; and sudden cardiac death. The impact of HBV and HCV coinfection on time to CVD was assessed using multivariable competing risk models accounting for left truncation between ART initiation and study enrolment.

RESULTS

A total of 3,416 HIV-monoinfected, 432 HIV-HBV- and 736 HIV-HCV-coinfected individuals were followed for a median (IQR) of 2.32 years (1.36-8.02). Over the study period, 167 CVD events and 613 deaths were documented. After adjustment for age, gender, race, year initiating ART, weight and smoking status, HBV was not associated with time to CVD onset (aHR=1.05, 95% CI [0.63, 1.74]; P=0.86). There was an elevated risk of CVD for HCV-coinfected individuals, which approached statistical significance (aHR=1.44, 95% CI [0.97, 2.13]; P=0.07).

CONCLUSIONS

Our results are consistent with a moderate increase of CVD among individuals with HIV-HCV coinfection relative to those with HIV infection alone, lending support to consideration of initiation of HCV antiviral treatment.

Incidence of diabetes mellitus in a population-based cohort of HIV-infected and non-HIV-infected persons: the impact of clinical and therapeutic factors over time

AIMS

To examine incidence density rate and correlates of incident diabetes mellitus in a cohort of HIV-infected individuals compared with matched non-HIV-infected persons.

METHODS

Data were obtained from the South Carolina Medicaid system and the enhanced HIV/AIDS Reporting System surveillance database for persons ≥ 18 years of age who had been attended to during the period 1994 to 2011. Time-dependent proportional hazards analysis and marginal structural models were used to analyse the data.

RESULTS

A total of 13 632 individuals (6816, 1:1 matched HIV-infected and non-HIV-infected persons; median age 39 years; 57% male) contributed 88 359 person-years of follow-up. Incidence rate of diabetes was higher in the non-HIV-infected group compared with the HIV-infected group (13.60 vs. 11.35 per 1000 person-years). Multivariable hazards analysis suggested a significantly lower risk of incident diabetes among HIV-infected persons treated with combination antiretroviral therapy compared with the matched non-HIV-infected persons (adjusted hazards ratio 0.55; 95% CI 0.46-0.65). Among HIV-infected persons, marginal structural modelling suggested a significantly higher risk of diabetes with cumulative exposure to protease inhibitors over the observation period (adjusted relative risk 1.35; 95% CI 1.03-1.78), but this association was not significant for exposure to non-nucleoside reverse transcriptase inhibitors. Overall, female gender, older age, non-white race/ethnicity, and pre-existing hypertension, dyslipidaemia, obesity and hepatitis C infection were associated with higher risk of diabetes incidence.

CONCLUSIONS

HIV infection may not be independently associated with increased risk of diabetes. Among HIV-infected persons, exposure to protease inhibitor-based regimens may increase the risk of diabetes. Healthcare providers should make every effort to use combination antiretroviral therapy regimens with a better cardiometabolic profile.

Hypothalamic-pituitary-adrenal axis in HIV infection and disease

HIV infection induces hypothalamic-pituitary-adrenal (HPA) axis derangements. Partial glucocorticoid resistance has been observed in a subset of AIDS patients, possibly owing to HIV-induced altered cytokine secretion and action. Because glucocorticoids have immunomodulatory effects, the severity of the HPA axis disorder could play a central role in disease progression. The characteristic phenotype of AIDS patients (visceral obesity, lipodystrophy) may be owing to effects of HIV proteins on the HPA axis, including changes in glucocorticoid and insulin sensitivity of target tissues, as well as altered cytokine production and interaction with the HPA axis, genetic causes, comorbidities, and, possibly, use of antiretroviral agents.

Effects of combination antiretroviral therapies on the risk of myocardial infarction among HIV patients

BACKGROUND

Cohort studies have demonstrated greater risk of myocardial infarction (MI) associated with specific antiretroviral use, while meta-analyses of randomized controlled trials (RCTs) have not. These differences may be due to inherent biases in the observational study design or to the limited duration of randomized trials. We conducted a new-user, active-comparator cohort study emulating an RCT comparing the initiation of several antiretrovirals as part of combination antiretroviral therapy (cART) and MI.

METHODS

We included North Carolina (NC) Medicaid beneficiaries infected with human immunodeficiency virus between 2002 and 2008 who were previously untreated with cART. We compared hazard ratios (HRs) and 95% confidence intervals (CIs) of MI between abacavir and tenofovir recipients, and lopinavir-ritonavir or atazanavir recipients and nonnucleoside reverse transcriptase inhibitor (NNRTI) recipients. We adjusted for confounding through inverse probability weighting methods.

RESULTS

There were 3481 NC Medicaid new cART recipients who contributed 6399 person-years and experienced 38 MI events. Receiving abacavir compared with tenofovir as part of cART was associated with an increased rate of MI (unadjusted HR = 2.70 [95% CI = 1.24-5.91]; adjusted HR = 2.05 [0.72-5.86]). Point estimates also suggest a relationship between receipt of atazanavir or lopinavir-ritonavir compared with an NNRTI and MI, although estimates were imprecise.

CONCLUSIONS

We found an increased rate of MI among patients initiating abacavir compared with tenofovir, although the association was decreased after confounding adjustment. Without a very large prospective comparative clinical trial, a much larger observational study of patients initiating cART would be needed to better define this apparent association.

Hepatitis C co-infection and severity of liver disease as risk factors for osteoporotic fractures among HIV-infected patients

Osteoporosis is increasingly reported in the aging HIV-positive population, and co-infection with hepatitis C virus (HCV) may further increase the risk of osteoporosis. However, it remains unclear whether HCV-related increased fracture risk is a function of the severity of liver disease. We calculated the time-updated alanine aminotransferase to platelet ratio index (APRI) score (an indirect marker of hepatic fibrosis) in all HIV-infected patients enrolled in the Veterans Affairs' Clinical Case Registry between 1984 and 2009. The association between HCV co-infection and incident osteoporotic fracture (defined as closed wrist, vertebral, or hip fracture) was assessed in univariate and multivariate Cox survival models adjusting for traditional risk factors for osteoporosis and APRI score or the presence of cirrhosis. A total of 772 osteoporotic fractures were identified among 56,660 HIV-infected patients (98.1% male; 31.3% HCV co-infected; median age 44.0 years) contributing 305,237 patient-years of follow-up. Fracture rates were significantly higher among HIV/HCV patients than HIV-only patients (2.57 versus 2.07/1000 patient-years, relative risk = 1.24, p < 0.0001). In a Cox multivariable model including age, race, smoking, drug use, body mass index, and antiretroviral therapy, HCV co-infection remained an independent predictor of osteoporotic fractures after controlling for presence of cirrhosis (hazard ratio [HR] = 1.32; p <0.001) or APRI score (HR = 1.30; p = 0.003). Among HIV/HCV co-infected patients, cirrhosis strongly predicted osteoporotic fractures (HR = 1.65; 95% confidence interval [CI] 1.11-2.44; p = 0.012), but APRI score was a weaker predictor (HR = 1.008; 95% CI 1.002-1.014; p = 0.015). In conclusion, among HIV-infected patients, severity of liver disease partly explains the HCV-associated increased risk of osteoporotic fractures. Other determinants of this increased risk remain to be defined.

Dysregulation of glucose metabolism in HIV patients: epidemiology, mechanisms, and management

HIV-infected patients on highly active antiretroviral therapy (HAART) have increased prevalence of a number of chronic metabolic disorders of multifactorial but unclear etiology. These include disorders of lipid metabolism with or without lipodystrophy, insulin resistance, and an increased prevalence of impaired glucose tolerance, diabetes mellitus, and cardiometabolic syndrome. While much attention has been focused on the lipid and cardiovascular disorders, few investigations have attempted to characterize the prevalence, incidence, etiology, mechanisms, and management of glycemic disorders in HIV patients. In this review, we have focused specifically on a comprehensive assessment of dysglycemia in the context of HIV infection and HAART.

Abacavir use and risk of acute myocardial infarction and cerebrovascular events in the highly active antiretroviral therapy era

BACKGROUND

Some studies have suggested that exposure to antiretroviral therapy (ART) with abacavir is associated with an increased risk of acute myocardial infarction (AMI).

METHODS

Using the Veterans Health Administration's Clinical Case Registry we calculated the risk of AMI and cerebrovascular events (CVA) associated with the cumulative use of abacavir and other nucleoside combinations. We also evaluated the impact of pre-existing chronic kidney disease on the selection of abacavir versus tenofovir in the last recorded ART regimen, and on highly active antiretroviral therapy-associated AMI and CVA risks.

RESULTS

A total of 19,424 human immunodeficiency virus-infected patients contributed 76,376 patient-years of follow. After adjusting for age, hypercholesterolemia, hypertension, type 2 diabetes, and smoking, the hazard ratio (HR) for each year of abacavir use was 1.18 (95% confidence interval [CI], .92-1.50; P=.191) for AMI and 1.16 (95% CI, .98-1.37; P=.096) for CVA. Abacavir use was more common among patients with prior chronic kidney disease than was tenofovir use (12.46% versus 7.15%; P=.0001), and chronic kidney disease was associated with a significantly higher risk of AMI (HR, 2.41; 95% CI, 1.73-3.36), and CVA (HR, 1.80; 95% CI, 1.44-2.24). Compared with patients who received neither tenofovir nor abacavir, patients who received tenofovir had lower risk of AMI (HR, 0.16; 95% CI, .08-.33; P=.0001) and CVA (HR, 0.22; 95% CI, .15-.32; P=.001). Use of abacavir was associated with lower risk of CVA (HR, 0.60; 95% CI, .45-.79).

CONCLUSIONS

We observed no association between cumulative or current abacavir use and AMI or CVA. Abacavir use was more common than was tenofovir use among patients with prior chronic kidney disease, and chronic kidney disease independently predicted higher rates of AMI and CVA.

Incident hyperglycaemia among older adults with or at-risk for HIV infection

BACKGROUND

HIV infection has been associated with development of prediabetes and diabetes. Optimum screening practices for these disorders in HIV-infected populations remain unclear.

METHODS

We screened 377 adults, with or at-risk for HIV infection, for incident hyperglycaemia (prediabetes or diabetes) using two oral glucose tolerance tests (OGTTs) a median of 18.6 months apart. We determined proportion of incident cases detected by fasting and 120-min plasma glucose levels. Independent predictors of incident hyperglycaemia were identified using logistic regression.

RESULTS

The baseline OGTT was consistent with diabetes in 7% of participants and with prediabetes in 31%. Among 352 normoglycaemic and prediabetic participants at baseline, 19 (5%) developed diabetes on follow-up. Among participants normoglycaemic at baseline, an additional 38 (16%) developed prediabetes. Overall 52% of incident hyperglycaemia cases were detected by fasting plasma glucose alone, 33% by a 120-min glucose level alone and 15% by both. Factors independently associated with incident hyperglycaemia included age ≥50 years and body mass index ≥30 kg/m(2). Neither HIV infection nor highly active antiretroviral therapy (HAART) use were associated with increased risk of diabetes.

CONCLUSIONS

Incident hyperglycaemia is common among older adults with or at-risk for HIV infection. HIV-infected individuals with classic diabetes risk factors should be screened for hyperglycaemia regardless of HAART use. OGTTs might be the preferred screening strategy in HIV-infected individuals at high risk for developing hyperglycaemia.

The prevalence and pathogenesis of diabetes mellitus in treated HIV-infection

HIV-associated morbidity and mortality have declined significantly since the introduction of highly active antiretroviral therapy (HAART). These developments have allowed an increased focus on associated adverse metabolic effects, such as dyslipidemia, diabetes mellitus, and insulin resistance, which are risk factors for cardiovascular disease and other adverse outcomes. The pathophysiologic mechanisms underlying the metabolic changes are complicated and not yet fully elucidated due to the difficulty of separating the effects of HIV infection from those of HAART, co-morbidities, or individual patient vulnerabilities. This article reviews studies concerning the prevalence and incidence of diabetes mellitus and HIV, HIV-specific effects on diabetes mellitus complications, and HIV-specific diabetes mellitus treatment considerations.

HBV or HCV coinfections and risk of myocardial infarction in HIV-infected individuals: the D:A:D Cohort Study

BACKGROUND

Data on a link between HCV or HBV infection and the development of cardiovascular disease among HIV-negative and HIV-positive individuals are conflicting. We sought to investigate the association between HBV or HCV infection and myocardial infarction in HIV-infected individuals.

METHODS

The prospective observational database of the D:A:D collaboration of 11 cohorts of HIV-infected individuals, including 212 clinics in Europe, the United States and Australia was used. Multivariate Poisson regression was used to assess the effect of HCV or HBV infection on the development of myocardial infarction after adjustment for potential confounders, including cardiovascular risk factors, diabetes mellitus and exposure to antiretroviral therapy.

RESULTS

Of 33,347 individuals, 517 developed a myocardial infarction over 157,912 person-years, with an event rate of 3.3 events/1,000 person-years (95% confidence interval [CI] 3.0-3.6). Event rates (95% CIs) per 1,000 person-years in those who were HCV-seronegative and HCV-seropositive were 3.3 (3.0-3.7) and 2.7 (2.2-3.3), respectively, and for those who were HBV-seronegative, had inactive infection or had active infection were 3.2 (2.8-3.5), 4.2 (3.1-5.2) and 2.8 (1.8-3.9), respectively. After adjustment, there was no association between HCV seropositivity (rate ratio 0.86 [95% CI 0.62-1.19]), inactive HBV infection (rate ratio 1.07 [95% CI 0.79-1.43]) or active HBV infection (rate ratio 0.78 [95% CI 0.52-1.15]) and the development of myocardial infarction.

CONCLUSIONS

We found no association between HBV or HCV coinfection and the development of myocardial infarction among HIV-infected individuals.

Hepatitis C virus coinfection and the risk of cardiovascular disease among HIV-infected patients

BACKGROUND

Among HIV-infected patients, hepatitis C virus (HCV) coinfection is associated with lower cholesterol levels, but it remains unclear how it affects cardiovascular outcomes.

METHODS

We performed logistic regression to evaluate acute myocardial infarction (AMI) and cerebrovascular disease (CVD) events by HCV status among HIV-infected US veterans in the highly active antiretroviral therapy (HAART) era (1996-2004). We then performed survival analyses to evaluate incident AMI and CVD, exploring antiretroviral therapy (ART) as a time-dependent variable.

RESULTS

A total of 19 424 HIV-infected patients [31.6% of whom were HCV-coinfected (HIV/HCV)] contributed 76 376 patient-years of follow-up. HCV coinfection was associated with lower rates of hypercholesterolaemia (18.0% in HIV/HCV vs. 30.7% in HIV-only patients; P<0.001), but higher rates of hypertension (43.8%vs. 35.6%; P<0.0001), type 2 diabetes mellitus (16.2%vs. 11.1%; P<0.0001) and smoking (36.7%vs. 24.7%; P=0.009). Rates of AMI and CVD were significantly higher among HIV/HCV than HIV-only patients: 4.19 vs. 3.36 events/1000 patient-years, respectively (P<0.001), for AMI; and 12.47 vs. 11.12 events/1000 patient-years, respectively (P<0.001), for CVD. When analyses were controlled for diabetes mellitus, hypertension, age and duration of ART, hazard ratios (HRs) among those with HIV/HCV (vs. HIV only) were 1.25 [95% confidence interval (CI) 0.98-1.61; P=0.072] for AMI and 1.20 (CI 1.04-1.38; P=0.013) for CVD. Hypertension (HR 2.05; P<0.001), greater age (HR 1.79; P<0.001) and longer duration (cumulative years) of antiretroviral use (HR 1.12; P=0.0411) were also associated with increased risk of AMI in the adjusted model.

CONCLUSIONS

In the HAART era, HCV coinfection was associated with a significantly increased risk of CVD and a trend towards an increased risk of AMI among HIV-infected patients.

HIV infection and the risk of diabetes mellitus

BACKGROUND

The influence of HIV infection on the risk of diabetes is unclear. We determined the association and predictors of prevalent diabetes mellitus in HIV infected and uninfected veterans.

METHODS

We determined baseline prevalence and risk factors for diabetes between HIV infected and uninfected veterans in the Veterans Aging Cohort Study. Logistic regression was used to determine the odds of diabetes in HIV infected and uninfected persons.

RESULTS

We studied 3227 HIV-infected and 3240 HIV-uninfected individuals. HIV-infected individuals were younger, more likely to be black males, have HCV coinfection and a lower BMI. HIV-infected individuals had a lower prevalence of diabetes at baseline (14.9 vs. 21.4%, P < 0.0001). After adjustment for known risk factors, HIV-infected individuals had a lower risk of diabetes (odds ratio = 0.84, 95% confidence interval = 0.72-0.97). Increasing age, male sex, minority race, and BMI were associated with an increased risk. The odds ratio for diabetes associated with increasing age, minority race and BMI were greater among HIV-infected veterans. HCV coinfection and nucleoside and nonnucleoside reverse transcriptase inhibitor therapy were associated with a higher risk of diabetes in HIV-infected veterans.

CONCLUSION

Although HIV infection itself is not associated with increased risk of diabetes, increasing age; HCV coinfection and BMI have a more profound effect upon the risk of diabetes among HIV-infected persons. Further, long-term ARV treatment also increases risk. Future studies will need to determine whether incidence of diabetes mellitus differs by HIV status.

Metabolic changes associated with antiretroviral therapy in HIV-positive patients

OBJECTIVE: To evaluate metabolic changes associated with highly active antiretroviral therapy (HAART) in HIV-positive patients, and to identify risk factors associated. METHODS: Retrospective study that included 110 HIV-positive patients who where on HAART in the city of Porto Alegre (Southern Brazil) between January 2003 and March 2004. Data on demographic variables, cigarette smoking, diabetes mellitus, cholesterol and triglyceride levels, stage of HIV infection, antiretroviral therapy and HCV coinfection were collected. General linear models procedure for repeated measures was used to test the interaction between HAART and HCV coinfection or protease inhibitor treatment. RESULTS: Total cholesterol, triglycerides, and glucose levels significantly increased after receiving HAART (p<0.001 for all variables), but no interaction with protease inhibitors was seen for total cholesterol, glucose and triglyceride levels (interaction treatment*protease inhibitors p=0.741, p=0.784, and p=0.081, respectively). An association between total cholesterol levels and HCV coinfection was found both at baseline and follow-up (effect of HCV coinfection, p=0.011). Glucose levels were increased by HAART (treatment effect, p=0.036), but the effect was associated to HCV coinfection (treatment*HCV effect, p=0.018). Gender, smoking habit, intravenous drug use and age were not significantly associated with cholesterol, triglyceride and glucose changes. CONCLUSIONS: HCV-infected patients at baseline were significantly less likely to develop hypercholesterolemia. The results provide further evidence of the role of HAART for the development of metabolic disturbances.

Hepatitis C, human immunodeficiency virus and metabolic syndrome: interactions

Significant concerns have been raised about the metabolic effects of antiretroviral medication, including the classic triad of dyslipidaemia, insulin resistance (IR) and characteristic alterations in fat distribution (lipoatrophy and lipohypertrophy). Co-infection with hepatitis C appears to exacerbate IR, reduce serum lipids and induce prothrombotic changes in the treated human immunodeficiency virus patient. The effects of co-infection are complex. While combination antiretroviral therapy has been shown to be associated with an increased risk of cardiovascular events through promotion of dyslipidaemia, IR and fat redistribution, co-infection exacerbates IR while reducing serum lipids. Co-infection also promotes a prothrombotic state characterized by endothelial dysfunction and platelet activation, which may enhance risk for cardiovascular disease. Consideration must be given to selection of appropriate treatment regimens and timing of therapy in co-infected patients to minimize metabolic derangements and, ultimately, reduce cardiovascular risk.

Antiretroviral therapy and the human immunodeficiency virus--improved survival but at what cost?

Patients infected with human immunodeficiency virus are living longer since the introduction of combination antiretroviral therapy more than a decade ago - but at what cost? Highly active antiretroviral therapy has been associated with lipodystrophy and associated metabolic derangements such as dyslipidaemia, insulin resistance and diabetes. These complications are likely to contribute to an increased risk of premature and accelerated atherosclerosis with growing concern about potential cardiovascular consequences.

Insulin resistance, glucose intolerance and diabetes mellitus in HIV-infected patients

An increased prevalence of insulin resistance, glucose intolerance and diabetes has been reported in HIV infection in the highly active antiretroviral therapy (HAART) era. This development might be clinically significant because of its association with cardiovascular morbidity and mortality as well as the therapeutic challenges of managing polypharmacy. The development of insulin resistance, glucose intolerance and diabetes could be related to the underlying HIV infection, the contribution of different antiretroviral agents, treatment-associated weight gain, immune restoration, as well as the non-HIV related factors. Dissecting these factors in clinical practice might be difficult. Clinical studies include short-term treatments in healthy, non-HIV-infected individuals; randomized, controlled trials; comparative studies of different HAART regimens; and randomized studies of switching regimens in patients with viral suppression and stable immune function. This article reviews the latest knowledge regarding the epidemiology, pathogenesis, prevention and treatment of insulin resistance, glucose intolerance and diabetes mellitus in HIV-infected individuals.