Mechanisms and strategies for insulin resistance in acquired immune deficiency syndrome

Histo-morphological and seminal evaluation of testicular parameters in diabetic rats under antiretroviral therapy: interactions with Hypoxis hemerocallidea

OBJECTIVES

Broad range of metabolic changes associated with highly active antiretroviral therapy (HAART) has been reported over decades including reproductive perturbations. The current study aimed at investigating the role of Hypoxis hemerocallidea (Hyp) in the seminal and morphometric alterations in the testes of streptozotocin-nicotinamide-induced diabetic rats under HAART.

MATERIALS AND METHODS

Sixty-two adult male Sprague-Dawley rats were divided into A-H groups, containing 6 rats in the control group A and 8 rats in the treatment groups B-H. Diabetes was induced by intraperitoneal injection of nicotinamide (110 mg/kg BW) followed by streptozotocin (45 mg/kg BW). The animals were then subjected to various treatments with HAART, Hyp, and melatonin.

RESULTS

weights (body and testicular), histological, histochemical, seminal fluid, and morphometric analyses were carried out. Sperm count and motility were reduced in HAART (P<0.05/0.003) and Hyp200 (P<.003) groups compared with normal and diabetic controls, respectively. Sperm count was higher (P<.003) in HAART+ Mel and HAART+Hyp100 groups. Morphometry showed the reduction in germinal epithelium height and basement membrane thickness (P<.003) in the Hyp100 group compared with diabetic controls. Adjuvant use of Hyp and melatonin with HAART did not significantly raise these indices (P>.05). Histological slides showed gross distortions in HAART, diabetic and HAART +Hyp groups with marked atrophy in tubules, germ cell loss and areas of focal depletion of the cell. PAS staining revealed detached basement membrane in diabetic groups with strong PAS-stain.

CONCLUSION

The use of Hyp or melatonin does not ameliorate the testicular damages in diabetic animals under antiretroviral therapy.

Magnitude and associated factors of diabetes mellitus and hypertension among adult HIV-positive individuals receiving highly active antiretroviral therapy at Jugal Hospital, Harar, Ethiopia

BACKGROUND

People with HIV infection are at increased risk of noncommunicable diseases (NCDs). Diabetes mellitus (DM) and hypertension are recognized as the major NCDs. Except few findings in general population, there is no well-documented evidence on the magnitude of NCDs and associated factors among HIV-positive patients.

PURPOSE

The aim of this study was to determine the magnitude and associated factors of DM and hypertension among adult HIV-positive subjects receiving highly active antiretroviral therapy (HAART).

METHODS

A hospital-based cross-sectional study was conducted from February to April at Jugal Hospital, Harar, Eastern Ethiopia. Sociodemographic and anthropometric data and blood pressure (BP) were collected by senior clinical nurses. A total of 5 mL of venous blood was collected. Serum glucose and lipid profile were measured using the Autolab 18 clinical chemistry analyzer. Data were analyzed using STATA version 13.

RESULTS

A total of 425 HIV-infected individuals taking HAART of age ranging from 18 to 68 years were included. The prevalence of DM and hypertension were 7.1% (95% CI: 4.9-9.9) and 12.7% (95% CI: 9.8-16.2), respectively. Increased blood triglyceride (adjusted odds ratio [AOR] =4.7, 95% CI: 1.7-13.1), high BP (AOR =3.3, 95% CI: 1.1-9.5), and high baseline body mass index (BMI) (AOR =8.7, 95% CI: 2.4-31.8) were significantly associated with DM. In contrast, raised waist-hip ratio (AOR =4.6, 95% CI: 1.6-13.3), raised blood glucose (AOR =3.5, 95% CI: 1.1-11.4), increased total cholesterol (AOR =3.9, 95% CI: 1.3-11.9), high current BMI (AOR =3.8, 95% CI: 1.5-9.6), drinking alcohol (AOR =3.4, 95% CI: 1.5-8.1), CD4 count <500 cell/mL (AOR =2.7, 95% CI: 1.3-5.6), and longer duration of HAART (AOR =2.3, 95% CI: 1.1-5.1) were significantly associated with hypertension.

CONCLUSION

DM and hypertension were frequent among HIV patients on HAART, and they were linked to the well-known risk factors. Therefore, regular screening and monitoring of DM and hypertension before and after the initiation of HAART is of paramount importance.

Fifteen-Year Trends in the Prevalence of Diabetes among Hospitalized HIV-Infected Patients in Spain (1997-2012)

OBJECTIVE

To describe trends in the prevalence of diabetes among hospitalized HIV-infected patients between 1997 and 2012 in Spain and compare them with those of age- and sex-matched non-HIV-infected patients.

METHODS

The study was based on Spanish national hospital discharge data. We performed a retrospective study for the period 1997-2012. HIV infection (HIV-infected versus non-HIV-infected [control group])and calendar period in relation to widespread use of combination antiretroviral therapy (cART) (1997-1999; 2000-2003; 2004-2007 and 2008-2012), were the exposure variables The outcome variables were diagnosis of diabetes and in-hospital mortality (IHM).

RESULTS

From 1997 to 2012, we identified 91,752 cases of diabetes: 15,398 in the HIV-infected group (403,277 hospital admissions) and 76,354 in the non-HIV-infected group (1,503,467 hospital admissions). Overall, HIV-infected patients had lower prevalence values for diabetes than non-HIV-infected patients throughout the follow-up (3.8% vs. 5.1%; p<0.001). The prevalence of diabetes increased 1.56-fold among non-HIV-infected patients and 4.2-fold among HIV-infected patients. The prevalence of diabetes in females was almost twice as high in HIV-infected patients as in non-HIV-infected patients during the last study period (4.72% vs. 2.88%; p<0.001). Diabetes showed a protective effect against IHM throughout the study period (aOR = 0.70; 95%CI, 0.65-0.75).

CONCLUSIONS

During the cART era, the prevalence of diabetes has increased sharply among HIV-infected hospitalized patients compared with matched non-HIV-infected subjects. The prevalence of diabetes is rising very fast among HIV-infected women. Diabetes has a protective effect on IHM among HIV-infected patients. Nevertheless, our study has several limitations. No information is available in the database used on important sociodemographic characteristics and relevant clinical variables including duration of the HIV infection, treatments used, drug resistance, treatment adherence or CD4 count, among others. Also, it is possible that increase of diabetes prevalence could reflect the improvement in recording habits.

Diabetes mellitus among HIV-infected individuals in follow-up care at University of Gondar Hospital, Northwest Ethiopia

OBJECTIVE

To assess the prevalence of diabetes mellitus (DM) and associated factors among HIV-infected adults in northwest Ethiopia.

DESIGN

Hospital-based cross-sectional study.

SETTING

HIV clinic of the University of Gondar Hospital, Ethiopia.

PARTICIPANTS

All HIV-infected adults who visited the HIV clinic from December 2013 to the end of February 2014 were the source population.

MEASURES

A structured and pretested questionnaire incorporating the WHO STEPwise approach was used. A multivariate logistic regression analysis was applied to assess factors associated with DM.

RESULTS

The overall prevalence of type 2 DM was 8% (95% CI 5.5% to 10.5%). The prevalence of DM was higher (13.2%; 95% CI 8.0% to 18.3%) among subjects receiving pre-antiretroviral treatment (pre-ART) than among those taking ART (5.1%; 95% CI 2.6% to 7.6%). Thirteen (35.1%) of the DM cases were newly identified during the study. Obesity (adjusted OR (AOR) 6.55; 1.20 to 35.8), hypertension (AOR 3.45; 1.50 to 7.90), being in the pre-ART group (AOR 4.47; 1.80 to 11.08), hypertriglyceridaemia (AOR 2.24; 1.02 to 49.5) and tertiary-level education (AOR 11.8; 2.28 to 61.4) were associated with DM.

CONCLUSIONS

Overall DM prevalence was high, particularly among subjects in the pre-ART group. More educated, hypertensive and obese HIV-infected adults were more likely to have DM as a comorbidity. Health policy and the clinical management of HIV-infected individuals should take into account the rising DM.

Metabolic disorders and cardiovascular consequences of HIV infection and antiretroviral therapy

Metabolic disturbances associated with HIV disease have become an important factor in patient management and have important implications for long-term outcomes, both in regards to mortality and healthcare burden. Recent research has implicated both HIV infection itself and specific antiretroviral therapies in the development of these disorders. This review examines recent findings from research into insulin and glucose dysregulation, serum lipid abnormalities, adipose tissue and derangements in bone metabolism. This review then describes the cardiovascular consequences and management of these metabolic disorders, and summarizes current thinking on the pathogenesis and effects of antiretroviral therapy. Finally, the review raises some questions regarding ongoing challenges and unmet needs in this field of research.

Risk of diabetes mellitus in persons with and without HIV: a Danish nationwide population-based cohort study

Objective

In a nationwide, population-based cohort study we assessed the risk of diabetes mellitus (DM) in HIV-infected individuals compared with the general population, and evaluated the impact of risk factors for DM in HIV-infected individuals.

Methods

We identified 4,984 Danish-born HIV-infected individuals from the Danish HIV Cohort Study and a Danish born population-based age- and gender-matched comparison cohort of 19,936 individuals (study period: 1996–2009). Data on DM was obtained from the Danish National Hospital Registry and the Danish National Prescription Registry. Incidence rate ratios (IRR) and impact of risk factors including exposure to Highly Active Antiretroviral Therapy (HAART) and antiretroviral drugs were estimated by Poisson regression analyses.

Results

In the period 1996–1999 risk of DM was higher in HIV-infected individuals compared to the comparison cohort (adjusted IRR: 2.83; 95%CI: 1.57–5.09), both before (adjusted IRR: 2.40; 95%CI: 1.03–5.62) and after HAART initiation (adjusted IRR: 3.24; 95% CI: 1.42–7.39). In the period 1999–2010 the risk of DM in HIV-infected individuals did not differ from that of the comparison cohort (adjusted IRR: 0.90; 95% CI: 0.72–1.13), although the risk was decreased before HAART-initiation (adjusted IRR: 0.45; 95%CI: 0.21–0.96). Increasing age, BMI and the presence of lipoatrophy increased the risk of DM, as did exposure to indinavir, saquinavir, stavudine and didanosine.

Conclusion

Native HIV–infected individuals do not have an increased risk of developing DM compared to a native background population after year 1998. Some antiretroviral drugs, not used in modern antiretroviral treatment, seem to increase the risk of DM.

Mortality of HIV-infected patients with or without cancer: comparison with the general population in Italy

BACKGROUND

HAART has reduced mortality in HIV-infected patients; however, the risk of non-AIDS-related events has increased, including cancer. We compared mortality in HIV-infected patients with or without cancer with the general population in Italy.

METHODS

Eligible patients were recorded in the San Raffaele Infectious Diseases Department database. The ratio of observed deaths to expected all-cause deaths (standardized mortality ratio [SMR]) was standardized for age and gender, and stratified by cancer occurrence or year of HIV infection (≤1998 or >1998). Expected all-cause deaths were obtained from the Istituto Superiore di Sanità (Rome, Italy; 2002 data).

RESULTS

Among 6,495 HIV-infected patients, contributing 75,171 person-years, the SMR was 6.0 (95% CI 5.7, 6.4); SMRs decreased as age increased. Mortality rates were significantly higher than the general population for patients with or without cancer (SMR=15.1 [95% CI 13.6, 16.7] and 4.8 [95% CI 4.5, 5.1], respectively). For patients with or without cancer, SMRs were higher in those aged <45 years than older patients. SMRs for patients with cancer were almost stable in those infected with HIV ≤1998 (15.3; 95% CI 13.7, 17.0) or >1998 (13.5; 95% CI 9.2, 19.1). Among patients with cancer diagnosed with HIV >1998, age-adjusted SMRs ranged from 216.0 (95% CI 43.4, 631.3) to 6.8 (95% CI 4.7, 9.7) in patients <30 years or ≥70 years, respectively.

CONCLUSIONS

Mortality in HIV-infected patients remains higher than the general population in Italy, with marked differences according to age, and cancer contributing to an increased excess of mortality.

Hypertriglyceridemia, Metabolic Syndrome, and Cardiovascular Disease in HIV-Infected Patients: Effects of Antiretroviral Therapy and Adipose Tissue Distribution

The use of combination antiretroviral therapy (CART) in HIV-infected patients has resulted in a dramatic decline in AIDS-related mortality. However, mortality due to non-AIDS conditions, particularly cardiovascular disease (CVD) seems to increase in this population. CART has been associated with several metabolic risk factors, including insulin resistance, low HDL-cholesterol, hypertriglyceridemia and postprandial hyperlipidemia. In addition, HIV itself, as well as specific antiretroviral agents, may further increase cardiovascular risk by interfering with endothelial function. As the HIV population is aging, CVD may become an increasingly growing health problem in the future. Therefore, early diagnosis and treatment of cardiovascular risk factors is warranted in this population. This paper reviews the contribution of both, HIV infection and CART, to insulin resistance, postprandial hyperlipidemia and cardiovascular risk in HIV-infected patients. Strategies to reduce cardiovascular risk are also discussed.

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.

Infection with HIV and HCV enhances the release of fatty acid synthase into circulation: evidence for a novel indicator of viral infection

Background

Fatty acid synthase (FASN) is an enzyme synthesized by the liver and plays an important role in lipogenesis. The present study aimed to investigate whether serum FASN concentration may provide a direct link between HIV and/or HCV viral infections and lipid metabolic disorders commonly observed in HIV/HCV-infected patients.

Methods

We evaluated serum FASN concentration in 191 consecutive HIV-infected patients in the absence or presence of HCV co-infection. For comparison, 102 uninfected controls were included. Metabolic and inflammatory phenotype was also compared with respect to the presence of HCV co-infection.

Results

Serum FASN concentration was significantly higher in HIV-infected patients than in healthy participants and HCV co-infected patients showed higher levels than those without co-infection. Levels were also affected by treatment regimen, but marginally influenced by virological variables. Insulin concentration was the sole variable among metabolic parameters that demonstrated a significant correlation with serum FASN concentrations. Serum alanine aminotransferase (ALT) values correlated significantly with serum FASN concentration and provided the best discrimination with respect to the presence or absence of HCV co-infection. In multivariate analysis, only ALT, monocyte chemoattractant protein-1 (MCP-1) and the presence of antiretroviral treatment regimen significantly contributed to explain serum FASN concentration in HIV/HCV co-infected patients.

Conclusion

Serum FASN concentration is significantly increased in HIV-infected individuals. The release of FASN into the circulation is further enhanced in patients who are co-infected with HCV. Subsequent studies should explore the usefulness of this indicator to monitor the effect of viral infections on disease progression and survival.

Atherosclerotic vascular disease in HIV: it is not just antiretroviral therapy that hurts the heart! Curr Opin HIV AIDS. 2007;2:324-331. [PMID: 19372907 DOI: 10.1097/coh.0b013e3281e38a98]

PURPOSE OF REVIEW

Although potent combination antiretroviral therapy has heralded an unparalleled improvement in the treatment of HIV-1-infected patients, the now well known metabolic complications of treatment, which include dyslipidemia, insulin resistance and changes in body fat distribution, are thought to contribute to an increased risk of atherosclerotic (cardio)vascular disease. Atherogenic changes in plasma lipids as well as some evidence of increased atherogenesis, however, had already been described in HIV-1-infected patients prior to the availability of combination antiretroviral therapy and even prior to that of suboptimal antiretroviral therapy. In this review, we will summarize the various possible factors and mechanisms involved in atherogenesis in HIV-1-infected individuals, with a focus on those mechanisms related to the infection itself and its immunological consequences.

RECENT FINDINGS

Recent data suggest that a treatment strategy involving repeated cycles of CD4-cell-guided combination antiretroviral therapy interruption is associated with a higher risk of (cardio)vascular disease than continuous treatment aimed at optimal viral suppression.

SUMMARY

Apart from the effects of combination antiretroviral therapy-associated metabolic derangements, HIV-1 infection, directly or indirectly, for instance by being associated with a state of chronic immune activation, may contribute to atherogenesis.

Nephrotoxicity associated with antiretroviral therapy in HIV-infected patients

BACKGROUND

With the success of modern antiretroviral therapies in increasing longevity of patients with HIV infection, chronic conditions including renal disease have assumed a greater importance in patient management. Some antiretroviral therapies have themselves been identified to have clinically significant nephrotoxicity.

OBJECTIVE

To review the risk factors and mechanisms for renal toxicity of antiretroviral drugs, and their impact on the clinical management of patients with HIV.

METHODS

Current literature and HIV treatment guidelines are reviewed.

RESULTS/CONCLUSIONS

Background rates of renal disease and associated risk factors are significant in the HIV clinic population, and renal function should be assessed in all HIV-infected patients. Modern HIV treatment regimens have a relatively low but clinically significant nephrotoxic potential; therefore, renal function should be evaluated on an ongoing basis in patients receiving antiretroviral therapy.

Disorders of glucose metabolism in human immunodeficiency virus-infected patients

Over the past 10 years, the development of highly active antiretroviral therapy (HAART) has dramatically improved morbidity and mortality in human immunodeficiency virus (HIV)-infected patients. Since the introduction of HAART however, unexpected metabolic abnormalities, including lipodystrophy, dyslipidaemia and dysregulation of glucose metabolism, are reported with increasing frequency in HIV-infected persons. Such metabolic disorders, if not treated, may be associated with an increased risk of cardiovascular disease in HIV-infected patients. In this paper, the prevalence, mechanisms and therapeutic strategies for the disorders of glucose metabolism in the context of HIV-infection are discussed.

Association of chronic hepatitis B virus infection with insulin resistance and hepatic steatosis

BACKGROUND AND AIM

Chronic viral infections such as human immunodeficiency virus and hepatitis C virus (HCV) may decrease tissue response to insulin, thereby causing insulin resistance. In addition, insulin resistance is associated with hepatic steatosis. However, whether these phenomena hold true for chronic hepatitis B virus (HBV) infection remains largely unknown. The present study therefore aimed to investigate the association of chronic HBV infection with insulin resistance and hepatic steatosis.

METHODS

A total of 507 subjects (243 men and 264 women; mean age 46.56 years) less than 60 years-old attending a health examination center were enrolled in the study. All the subjects were negative for antibodies against HCV and consumed less than 140 g alcohol/week. Demographic, anthropometric, clinical, and laboratory data were obtained from each subject. Insulin resistance index was determined using homeostasis model assessment (HOMA-IR). Hepatic steatosis was identified by ultrasound examination.

RESULTS

Of the 507 subjects, 50 (9.9%) were positive for hepatitis B surface antigen (HBsAg) and designated HBV carriers. All variables were comparable between HBV carriers and non-HBV carriers, except that HBV carriers had significantly higher serum alanine aminotransferase and aspartate aminotransferase levels (P < 0.05). By multivariate linear regression, HBV carriers were not associated with insulin resistance. In addition, multivariate regression analyses showed that HBV carriers were not associated with the presence of ultrasonographic fatty liver.

CONCLUSIONS

Chronic HBV infection seems not to be associated with insulin resistance or hepatic steatosis in HBV carriers.

Insulin resistance impairs rapid virologic response in HIV/hepatitis C virus coinfected patients on peginterferon-alfa-2a

OBJECTIVES

To investigate the association between insulin resistance and rapid virologic response.

DESIGN

All consecutive HIV/hepatitis C virus coinfected patients who started peg-interferon alpha-2a (180 microg/week) and ribavirin 1000-1200 mg/day were analysed.

METHODS

Insulin resistance was defined according to the homeostasis model of assessment-insulin resistance calculated as fasting insulin (mIU/l) x fasting glucose (mmol/l)/22.5. Rapid virologic response was defined as testing negative for hepatitis C virus-RNA after 4 weeks of therapy. Fasting levels of insulin and glucose in plasma were measured in all patients on the first day of treatment. Hepatitis C virus-RNA was determined by quantitative PCR assay (version 3.0). Hepatitis C virus-RNA was measured by qualitative PCR assay (COBAS 2.0) after 4 weeks of treatment.

RESULTS

Seventy-four HIV/hepatitis C virus coinfected patients were enrolled [mean age 41.7 years (SD 5.3), 61 men, 54.1% with advanced fibrosis (F3-4 according to METAVIR classification), 52.4% with infection by hepatitis C virus genotype 1 or 4]. Rapid virologic response was reached by 30 subjects. In the multivariate analysis the independent predictors of rapid virologic response were: genotype 1 or 4 [adjusted odds ratio 0.18 (0.06-0.55)], hepatitis C virus-RNA < 400.000 UI/ml [adjusted odds ratio 0.229 (0.09-0.92)] and homeostasis model of assessment-insulin resistance more than 3.00 [adjusted odds ratio 0.1 (0.05-0.6)].

CONCLUSION

The homeostasis model of assessment-insulin resistance score should be evaluated and possibly corrected before starting anti-hepatitis C virus therapy.

A randomized placebo-controlled trial of metformin for the treatment of HIV lipodystrophy

OBJECTIVE

We conducted a randomized placebo-controlled trial to examine the effects of metformin on visceral adipose tissue (VAT), appendicular fat, lipid profile and insulin sensitivity in HIV-infected persons with central adiposity and mild insulin resistance.

METHODS

Forty-eight HIV-infected men and women with a self-reported increase in abdominal girth and an abnormal waist-to-hip ratio were randomly assigned in double-blind fashion to receive metformin 1500 mg or placebo daily for 24 weeks. Persons with diabetes were excluded. The following measures were obtained at baseline and 24 weeks: single-slice computed tomography (CT) scan, dual-energy X-ray absorptiometry (DEXA), lipid profile and oral glucose tolerance test.

RESULTS

The median fasting insulin concentration of all participants was 12.3 microU/mL. The percentage change in VAT was not significantly different between the metformin and placebo groups in univariate analysis and linear regression analysis adjusting for age, height, baseline VAT and insulin area under the curve (10.1% vs 3.2%; P=0.58). Metformin was associated with a significant decrease in appendicular fat mass compared with placebo (-686.0 vs 161.0 g; P=0.03). There was no significant change in lipid profile or insulin sensitivity between the two groups at 24 weeks.

CONCLUSION

Metformin should be used with caution in the treatment of HIV lipodystrophy, and, if used, should be reserved for persons with adequate peripheral fat and marked insulin resistance.

Therapy insight: Body-shape changes and metabolic complications associated with HIV and highly active antiretroviral therapy

Increasingly effective therapies for HIV infection are now available. These treatments, referred to collectively as highly active antiretroviral therapy, comprise various combinations of anti-HIV drugs from different drug classes. Recently, a range of metabolic complications have emerged as important toxicities in treated patients. Complications present as abnormalities of body-fat mass distribution in association with an often significant dyslipidemia and glucose homeostasis dysregulation. The body-shape changes, manifesting as peripheral lipoatrophy or central lipohypertrophy, can have a negative impact on quality of life and consequently on adherence to treatment. The combination of central lipohypertrophy, dyslipidemia and insulin resistance is associated with accelerated rates of atherosclerosis and other potentially significant long-term effects. The pathogenesis of these effects is complex and is still being actively investigated. Possible contributing factors relate to host characteristics, HIV viral parameters and specific effects of anti-HIV drugs on adipose-tissue biology and on intermediary metabolism. Management of these complications involves manipulation of the anti-HIV drugs using an understanding of their particular effects on lipid and glucose metabolism, in association with standard therapeutic interventions. Individualized approaches, taking into consideration quality-of-life issues, and assessment of potential cardiovascular risks, are now an important component of effective care of HIV-infected patients.

Cardiovascular risk score change in HIV-1-infected patients switched to an atazanavir-based combination antiretroviral regimen

BACKGROUND

We aimed to establish whether the limited impact of atazanavir on the plasma lipid profile could translate into a reduction in the predicted cardiovascular risk in antiretroviral (ARV)-experienced patients switching to an atazanavir-containing regimen.

METHODS

HIV-1-infected treatment-experienced patients, switched to atazanavir for whatever reason and without prior major cardiovascular events, were selected and followed for at least 1 month. An individual cardiovascular risk score (10-year risk of major cardiovascular events) based on validated events and measurable risk factors in Italian cardiovascular cohorts was calculated using software available online.

RESULTS

A total of 197 patients were selected for inclusion in the study. After switching to atazanavir, the mean changes from pre-switch to last available measurement were -6.5% (P<0.001) for total cholesterol, -1.7% (P=0.029) for high-density lipoprotein (HDL) cholesterol, -11.3% (P<0.001) for non-HDL cholesterol and -8.6% (P<0.001) for triglycerides. The crude cardiovascular risk score was reduced from 3.43 to 3.38% (P=0.51); the analysis normalized by age showed a reduction from 3.43 to 3.14% (P<0.001). Subsets of patients with high baseline total cholesterol or triglycerides showed more marked reductions.

CONCLUSIONS

A treatment switch to atazanavir caused significant reductions in plasma lipids and a modest but significant reduction in the normalized-for-age cardiovascular risk score. Efforts should be made to concomitantly reduce the other preventable cardiovascular risk factors.

Effect of rosiglitazone and metformin on insulin resistance in patients infected with human immunodeficiency virus receiving highly active antiretroviral therapy containing protease inhibitor: randomized prospective controlled clinical trial

AIM

To evaluate and compare effects of 48-week treatment with rosiglitazone and metformin on insulin resistance in patients infected with Human Immunodeficiency Virus (HIV) receiving highly active antiretroviral therapy (HAART), containing a protease inhibitor.

METHODS

Randomized prospective controlled clinical trial enrolled 90 male patients infected with HIV and having impaired glucose tolerance and insulin resistance (fasting insulin concentration >20 mIU/L). The patients were randomly assigned into three groups; the first group receiving 4 mg rosiglitazone once a day, the second group receiving 500 mg metformin two times a day, and the third group serving as control without hypoglycemic treatment. The primary efficacy parameters were fasting plasma glucose and insulin levels compared between baseline and week. Data on insulin resistance and beta cell function were analyzed by the Homeostasis Model Assessment (HOMA).

RESULTS

After 48 weeks of treatment, the fasting insulin concentration (+/-standard deviation) in rosiglitazone group significantly declined from 39.0+/-3.35 to 19.7+/-3.99 mIU/L (P<0.001; 49% decrease) and in metformin group from 40.3+/-2.29 to 29.2+/-2.82 mIU/L (P<0.001; 27% decrease). HOMA indicated that rosiglitazone significantly reduced insulin resistance from 11.3+/-1.03 to 4.0+/-0.95 (P<0.001), compared with metformin which reduced it from 11.9+/-0.73 to 5.7+/-0.62 (P<0.001). Insulin resistance was significantly lower in the rosiglitazone group after 48 weeks (P<0.001). Metformin significantly improved beta cell function (from 257.3+/-21.91 to 707.4+/-207.32; P<0.001), as did rosiglitazone as well (from 261.3+/-27.98 to 403.3+/-162.50; P<0.001), but the improvement in the metformin group was significantly better (P<0.001). However, metformin was more efficient in improving beta cell function (from 257.3+/-21.91 to 707.4+/-207.32) than rosiglitazone (from 261.3+/-27.98 to 403.3+/-162.50).

CONCLUSIONS

Both rosiglitazone and metformin were effective and well tolerated in HIV treated with protease inhibitor-containing HAART. Rosiglitazone significantly more reduced insulin resistance, while beta cell function was significantly better in patients on metformin. Both drugs may be considered as an appropriate therapy, with rosiglitazone being a better alternative in treating insulin resistance in this patient population. ClinicalTrials.gov trial registration number: NCT00483392.

Cervical lipomatosis in HIV-infected patients: a case-control study

OBJECTIVES

The aim of the study was to analyse the prevalence of cervical lipomatosis (CL) in HIV-infected patients on highly active antiretroviral therapy (HAART) and the factors associated with its development.

METHODS

This was a multicentre, observational, 1:1 case-control study. HIV-infected patients with CL (cases) and HIV-infected patients from the same cohort, controlled for age (+/-5 years), sex and body mass index (+/-2.5 kg/m(2)) (controls), were included in the study, and a multiple conditional logistic regression was performed to identify factors related to CL.

RESULTS

CL was reported in 80 patients (1.8%) from a cohort of 4214 patients on HAART followed up in 10 Spanish hospitals. CL was associated with time of exposure to stavudine [for each 6-month increase, odds ratio (OR) 5.82, 95% confidence interval (CI) 5.70-5.94, P=0.0073] and lipoatrophy (OR 8.04, 95% CI 2.93-22.02, P=0.00001).

CONCLUSIONS

Although lipodystrophy is very frequent among HIV-infected patients on HAART, CL is an uncommon type of fat redistribution in this population, and in our cohort it was related to time of exposure to stavudine and lipoatrophy.

Long-term psychometric outcomes of facial lipoatrophy therapy: forty-eight-week observational, nonrandomized study

The aim of this observational, prospective, nonrandomized study was to assess long-term psychometric outcomes of surgical treatment of HIV-related facial lipoatrophy. Two hundred ninety-nine participants (70.8% male) consecutively attending the Metabolic Clinic of Modena and Reggio Emilia University from November 2005 to July 2006, undergoing surgical interventions for HIV-related facial lipoatrophy were enrolled. Fifty-four (18.1%) underwent facial lipofilling, which consists of the harvesting of a small, intact parcel of fatty tissue with processing that removes the nonviable components and of the transport of fatty parcels through a small cannula to implant the graft in a manner that provides nutrition and anchors the fat to the host tissue. After an initial lipofilling, 24 (8%) needed polylactic acid injections to correct cheek asymmetry, 91 (30.4%) received only polylactic acid infiltrations, and 130 (43.5%) polyacrylamide infiltrations only. Subjective outcome measures were face aesthetic satisfaction, body image perception, depression evaluated by a visual analogue scale (VAS), the Assessment of Body Change and Distress questionnaire (ABCD), and by the Beck Depression Inventory questionnaire, respectively. Objective measure was cheek thickness evaluated by a 7.5-MHz frequency ultrasound probe perpendicular to the skin surface at the nasolabial fold, the corner of the mouth, the zygomatic arch, and centrally between these points in the buccal fat pad area. Both subjective and objective variables were evaluated at baseline and 48 weeks after end of surgical treatment. All 299 participants had significant improvement of the aesthetic satisfaction for the face (VAS from 2.9 +/- 2.1 to 6.2 +/- 2.1, p < 0.0001), of body image satisfaction (ABCD question 7 from 3.8 +/- 1 to 3.1 +/- 1 p < 0.0001 and ABCD question 8 from 70.7 +/- 16.7 to 77.2 +/- 17.2 p < 0.0001), of depression score (Beck score from 11.4 +/- 8.3 to 9.4 +/- 7.8 p = 0.001). Participants experienced a significant augmentation of both cheeks' thickness (right cheek from 4.3 +/- 1.9 mm to 9.5 +/- 3 mm p < 0.0001, left cheek from 4.4 +/- 2 mm to 9.6 +/- 3.1 mm, p < 0.0001). Our data suggest that facial surgery is an important option in the treatment of HIV-related lipoatrophy as an integral part of the management of HIV infection, because of the important and lasting psychological benefits.

Off-Label Use of Exenatide for the Management of Insulin-Resistant Type 1 Diabetes Mellitus in an Obese Patient with Human Immunodeficiency Virus Infection

Exenatide is an incretin mimetic indicated for the treatment of type 2 diabetes mellitus in combination with a sulfonylurea, a thiazolidinedione, metformin, or metformin plus a sulfonylurea or thiazolidinedione. Exenatide lowers postprandial blood glucose levels by stimulating glucose-dependent insulin secretion, inhibiting glucagon secretion, slowing gastric emptying, and increasing satiety. Therapy with exenatide often results in weight loss, which further assists in decreasing insulin resistance. This feature makes the drug an attractive therapeutic option for obese patients. We report the successful off-label use of exenatide in an obese, 40-year-old man with type 1 diabetes and human immunodeficiency virus (HIV) infection who had gastrointestinal intolerance to pramlintide. The patient had experienced a dramatic weight gain secondary to his antiretroviral drugs. This weight gain led to insulin resistance and the development of type 2 diabetes; thus he had characteristics of both types 1 and 2 diabetes, or double diabetes. Before the start of exenatide therapy, he weighed 123 kg, had a body mass index of 42.3 kg/m(2), and had a suboptimal hemoglobin A(1c) value of 8.7%. After 11 months of therapy, the patient lost 24 kg (19.5% of his body weight) and achieved a hemoglobin A(1c) value of 7.3%. His basal insulin requirement was reduced by 25%, and his use of short-acting insulin before breakfast and before dinner was discontinued. In addition, the patient's quality of life substantially improved, as he was able to return to work and exercise after being nearly incapacitated by his weight. To our knowledge, this is the first published case report of the use of exenatide in a patient with type 1 diabetes mellitus or human immunodeficiency virus infection. Given this experience, exenatide may prove to be a useful alternative in selected patients with type 1 diabetes.

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.

Mortality in the highly active antiretroviral therapy era: changing causes of death and disease in the HIV outpatient study

BACKGROUND

AIDS-related death and disease rates have declined in the highly active antiretroviral therapy (HAART) era and remain low; however, current causes of death in HAART-treated patients remain ill defined.

OBJECTIVE

To describe mortality trends and causes of death among HIV-infected patients in the HAART era.

DESIGN

Prospective, multicenter, observational cohort study of participants in the HIV Outpatient Study who were treated from January 1996 through December 2004.

MEASUREMENTS

Rates of death, opportunistic disease, and other non-AIDS-defining illnesses (NADIs) determined to be primary or secondary causes of death.

RESULTS

Among 6945 HIV-infected patients followed for a median of 39.2 months, death rates fell from 7.0 deaths/100 person-years of observation in 1996 to 1.3 deaths/100 person-years in 2004 (P=0.008 for trend). Deaths that included AIDS-related causes decreased from 3.79/100 person-years in 1996 to 0.32/100 person-years in 2004 (P=0.008). Proportional increases in deaths involving liver disease, bacteremia/sepsis, gastrointestinal disease, non-AIDS malignancies, and renal disease also occurred (P=or<0.001, 0.017, 0.006, <0.001, and 0.037, respectively.) Hepatic disease was the only reported cause of death for which absolute rates increased over time, albeit not significantly, from 0.09/100 person-years in 1996 to 0.16/100 person-years in 2004 (P=0.10). The percentage of deaths due exclusively to NADI rose from 13.1% in 1996 to 42.5% in 2004 (P<0.001 for trend), the most frequent of which were cardiovascular, hepatic, and pulmonary disease, and non-AIDS malignancies in 2004. Mean CD4 cell counts closest to death (n=486 deaths) increased from 59 cells/microL in 1996 to 287 cells/microL in 2004 (P<0.001 for trend). Patients dying of NADI causes were more HAART experienced and initiated HAART at higher CD4 cell counts than those who died with AIDS (34.5% vs 16.8%, respectively, received HAART for 4 of more years, P<0.0001; 22.4% vs 7.8%, respectively, initiated HAART with CD4 cell counts of more than 350 cells/microL, P<0.001).

CONCLUSIONS

Although overall death rates remained low through 2004, the proportion of deaths attributable to non-AIDS diseases increased and prominently included hepatic, cardiovascular, and pulmonary diseases, as well as non-AIDS malignancies. Longer time spent receiving HAART and higher CD4 cell counts at HAART initiation were associated with death from non-AIDS causes. CD4 cell count at time of death increased over time.

Effects of atazanavir/ritonavir and lopinavir/ritonavir on glucose uptake and insulin sensitivity: demonstrable differences in vitro and clinically

BACKGROUND

The HIV protease inhibitor (PI) atazanavir does not impair insulin sensitivity acutely but ritonavir and lopinavir induce insulin resistance at therapeutic concentrations.

OBJECTIVE

To test the hypothesis that atazanavir combined with a lower dose of ritonavir would have significantly less effect on glucose metabolism than lopinavir/ritonavir in vitro and clinically.

METHODS

Glucose uptake was measured following insulin stimulation in differentiated human adipocytes in the presence of ritonavir (2 micromol/l) combined with either atazanavir or lopinavir (3-30 micromol/l). These data were examined clinically using the hyperinsulinemic euglycemic clamp and oral glucose tolerance testing (OGTT) in 26 healthy HIV-negative men treated with atazanavir/ritonavir (300/100 mg once daily) and lopinavir/ritonavir (400/100 mg twice daily) for 10 days in a randomized cross-over study.

RESULTS

Atazanavir inhibited glucose uptake in vitro significantly less than lopinavir and ritonavir at all concentrations. Ritonavir (2 micromol/l) combined with either atazanavir or lopinavir (3-30 micromol/l) did not further inhibit glucose uptake. During euglycemic clamp, there was no significant change from baseline insulin sensitivity with atazanavir/ritonavir (P = 0.132), while insulin sensitivity significantly decreased with lopinavir/ritonavir from the baseline (-25%; P < 0.001) and from that seen with atazanavir/ritonavir (-18%; P = 0.023). During OGTT, the HOMA insulin resistance index significantly increased from baseline at 120 min with atazanavir/ritonavir and at 150 min with lopinavir/ritonavir. The area under the curve of glucose increased significantly with lopinavir/ritonavir but not with atazanavir/ritonavir.

CONCLUSIONS

Both glucose uptake in vitro and clinical insulin sensitivity in healthy volunteers demonstrate differential effects on glucose metabolism by the combination PI atazanavir/ritonavir and lopinavir/ritonavir.

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

Insulin resistance is associated with highly active antiretroviral therapy in HIV-infected patients, and the risk of developing insulin resistance is increased in hepatitis C virus (HCV)-infected patients. The aim of the present study was to determine whether hepatitis C virus infection constitutes an additional risk factor for insulin resistance or other prothrombotic conditions in HIV-HCV coinfected patients under highly active antiretroviral therapy. One hundred eighteen HIV-infected patients were studied: 50 who had no history of anti-HIV treatment and 68 who were receiving therapy with highly active antiretroviral treatment. The treatment-naive group consisted of 35 HCV-negative subjects and 15 HCV-positive ones. Within the treated group, 50 patients were HCV negative and 18 were HCV positive. For each patient, the lipid profile was determined and the following values measured: glucose, soluble P-selectin (as a marker of platelet activation), soluble thrombomodulin, von Willebrand factor and soluble vascular cell adhesion molecule-1 (as endothelial markers), and insulin resistance. No significant difference (p>0.05) for any variable was found among subjects with or without HCV coinfection in the treatment-naïve group. Among patients under highly active antiretroviral therapy, however, those with HCV coinfection showed higher values (p<0.05) for insulin resistance (homeostasis model assessment value: 2.65 vs. 1.79), glucose (93 vs. 86 mg/dl), endothelial markers (von Willebrand factor, 204 vs. 123%; soluble vascular cell adhesion molecule-1, 650 vs. 482 ng/ml), and platelet activation marker (soluble P-selectin, 78 vs. 51 ng/ml) in parallel with lower CD4+ cells counts (289 vs. 402 cells/mm3) and higher HIV-1 viral loads (305 vs. 50 copies/ml) compared to patients without HCV coinfection. Glucose, soluble P-selectin, and von Willebrand factor were independently related to HCV infection. The presence of HCV coinfection during HIV treatment was closely related to higher values of insulin resistance, to activated platelets, and to endothelial perturbation in parallel with lower CD4+ cell counts and higher HIV-1 viral loads compared to patients without HCV coinfection. On the basis of these results, it may be preferable to treat HCV infection prior to initiating treatment for HIV infection in HIV-HCV-coinfected patients.

Disorders of glucose metabolism in the context of human immunodeficiency virus infection

PURPOSE

To discuss the pathophysiology and the current treatment approaches for the dysregulation of glucose metabolism in the context of human immunodeficiency virus (HIV) infection.

DATA SOURCES

Selected research, clinical studies, clinical guidelines, and review articles.

CONCLUSIONS

In HIV infection, multiple factors are associated with the pathogenesis of glucose dysregulation. Studies suggest that protease inhibitors, a class of antiretroviral agent, as well as viral factors, lipodystrophy, hepatitis C infection, injection drug use, and second-generation antipsychotics have been implicated in the development of glucose disorders and diabetes. Current treatment recommendations are based on extrapolated data from non-HIV diabetic patients. More research is needed to establish the most appropriate management for the disorders of glucose metabolism in the context of HIV infection.

IMPLICATIONS FOR PRACTICE

If left untreated, patients are at increased risk for cardiovascular disease and complications associated with untreated diabetes.

[Antiretroviral treatments-related lipodystrophy syndrome: clinico-pathological findings]

Effective therapies are available that can stop or slow down the progression of HIV infection. Highly active antiretroviral therapy (HAART) is a combination of antiretroviral drugs such as viral protease inhibitors or nucleoside-analogue reverse-transcriptase inhibitors. Among the side effects due to these drugs, lipodystrophy is a pathology characterized by fat wasting in face and limbs, accumulation of visceral fat, breast adiposity, cervical fat-pads, hyperlipidemia (hypertriglyceridemia and hypercholesterolemia), insulin resistance, and lactic acidemia. The main clinical features include peripheral fat loss (presumed lipoatrophy in the face, limbs, and buttocks) and central fat accumulation (within the abdomen, breasts, and over the dorsocervical spine, so-called "buffalo hump"). Histopathological features disclose a peculiar type of involutional lipodystrophy. Skin biopsies generally show thinning of the subcutaneous fat, associated with fibrosis, lipogranuloma and sometimes vessel proliferation. There is still an open debate concerning the precise responsibility of HAART as well as the metabolic pathways and mechanisms that are involved in the onset of lipodystrophy. There is no proven therapy for any component of lipodystrophy syndrome.

Functional and structural markers of atherosclerosis in human immunodeficiency virus-infected patients

OBJECTIVES

We investigated functional and structural markers of atherosclerosis in human immunodeficiency virus (HIV)-infected patients in relation to the presence of the metabolic syndrome (MS).

BACKGROUND

Antiretroviral combination therapy in HIV has been associated with cardiovascular risk factors that cluster in the MS.

METHODS

Thirty-seven HIV-infected patients underwent assessment of flow-mediated vasodilation (FMD), aortic pulse-wave velocity (PWV), and carotid intima-media thickness (IMT). Age-matched type 2 diabetic patients (n = 13) and healthy controls (n = 14) served as reference groups.

RESULTS

Fifteen HIV-infected patients (41%) fulfilled the National Cholesterol Education Program criteria of the MS. The FMD was similarly impaired in HIV-infected patients without the MS (MS- group) and the diabetic patients (5.1 +/- 0.4% and 4.9 +/- 0.6%, respectively) compared with controls (8.8 +/- 0.7%). The HIV-infected patients with the MS (MS+ group) had even more impaired FMD (2.5 +/- 0.3%). Carotid IMT was similarly increased in the MS+ group and the diabetic patients compared with the other groups. Aortic PWV was increased in the diabetic patients only. In HIV-infected patients, FMD was related to metabolic parameters, whereas aortic PWV and IMT were related to parameters of HIV infection, time on antiretroviral combination therapy, inflammatory (C-reactive protein and leukocytes) and metabolic parameters.

CONCLUSIONS

The data of the present study suggest an increased cardiovascular risk in HIV-infected patients, even in the absence of clustering of metabolic risk variables. The presence of the MS in HIV is associated with even more advanced atherosclerotic changes. Presumably, both HIV infection and antiretroviral therapy may promote atherosclerosis through mechanisms involving endothelial cells, either directly or indirectly via metabolic risk factors.

Non-alcoholic fatty liver disease in HIV-positive patients predisposes for acute-on-chronic liver failure: two cases

Non-alcoholic fatty liver disease is a prominent feature in HIV-positive patients. We present two patients with long-lasting HIV-infection who suffered from this disease, as induced by highly active anti-retroviral therapy (HAART). The patients developed acute-on-chronic (AOC) liver failure after either (case 1) acute infection with hepatitis A virus (HAV) or (case 2) methamphetamine abuse ('Ecstasy'). Approximately 1 week after visiting an area endemic for HAV, case 1, a male patient, presented with icterus, elevated liver transaminases and HAV IgM. Previous examinations had demonstrated normal liver transaminase activities while hepatic steatosis had been suspected. He developed complications associated with liver failure including renal failure as well as pleural and pericardial effusions. Case 2, a second male patient, developed both liver failure and lactic acidosis 24 h after methamphetamine abuse. Both patients suffered from fatty liver in the pre-acute stage as indicated by ultrasound examination. After developing symptoms of liver failure, HAART was discontinued in both patients. Follow-up visits demonstrated that the patients recovered clinically with almost normalized laboratory parameters. In HIV infection, HAART-induced hepatopathological alterations may exist despite the absence of relevant laboratory parameters. These patients are likely to develop AOC liver failure when subjected to acute risk factors such as hepatitis viruses and narcotics or other drugs. In patients treated with HAART, we thus highly recommend hepatitis A and B virus vaccinations, and close monitoring of liver parameters.

Glitazones and the management of insulin resistance: what they do and how might they be used

Thiazolidinediones (glitazones) are the only compounds currently available that specifically target tissue insulin resistance. The two currently available drugs in this class, pioglitazone and rosiglitazone,are approved by the Food and Drug Administration for the treatment of type 2 diabetes mellitus only. The therapeutic potential of the glitazones for other consequences of insulin resistance has stirred considerable interest, especially with regard to their potential beneficial impact on atherosclerotic cardiovascular disease and diabetes prevention. They also have been considered in the management of polycystic ovarian syndrome, nonalcoholic fatty liver disease, and other consequences of insulin resistance. The nonglycemic potential of glitazones is a clinical area in rapid evolution, wherein most data are on the impact of the glitazones onsurrogate markers that are associated with diseases, not on disease outcomes. This article provides insight and guidance to clinicians on the diverse nonglycemic potential of glitazones until conclusive outcome data become available.

Benfluorex as a therapeutic option for insulin resistance in HIV lipodystrophy syndrome

BACKGROUND

HIV lipodystrophy syndrome, characterized by a significant excess of visceral adiposity and a reduced subcutaneous fat mass in association with insulin resistance and dyslipidemia, still affects the majority of antiretroviral-treated HIV-infected patients. The therapeutic management of this syndrome has not yet been well established. Benfluorex is known to decrease insulin resistance with no side effects on lactate levels in HIV-negative patients.

METHOD

We conducted an open-label study of benfluorex (150 mg, 2-3 times a day) that was prescribed for 60 HIV-infected patients who were diagnosed with glucose metabolism abnormalities by oral glucose tolerance test (OGTT); 47 of these patients had visceral fat accumulation measured by computed tomography (VAT). Median follow-up was 12 months (interquartile range [IQR] = 6-12 months). The great majority of patients (90%) were treated with at least triple therapy (in 70% the therapy included at least one PI), with a nonsignificant change over the study period.

RESULTS

Added to antiretroviral therapy, benfluorex improved OGTT in 47/60 cases, including total normalization in 34/60 without lactate concentration modification. A trend toward a decrease in VAT distribution was observed (p =.06). No significant difference was observed in subcutaneous fat distribution, although an increase in subcutaneous thigh adipose tissue was observed in 17/47 (36.2%) cases and 6 patients (12.7%) presented both subcutaneous fat increase and VAT decrease.