LDL-receptors expression in HIV-infected patients: relations to antiretroviral therapy,hormonal status,and presence of lipodystrophy

BACKGROUND: Abnormalities in lipid levels and lipodystrophy (LD) have been commonly reported after commencement of highly active antiretroviral therapy (HAART). A major mechanism by which plasma low-density lipoprotein (LDL) cholesterol levels may be influenced is via the regulation of hepatic LDL receptor expression. The activity of LDL receptors is under hormonal control. Moreover, HIV infection and HAART are associated with important modifications of hormonal status. As the cause of these adverse reactions is unknown, the effects of HAART and lipodystrophy on LDL receptors were evaluated. MATERIALS AND METHODS: Thirty-nine HIV treated patients (21 with a protease inhibitor (PI) containing regimen, 18 without PI use) and 22 control subjects were tested for insulin resistance (HOMA model assessment), lipid profile, serum concentration of dehydroepiandrosterone (DHEA) and LDL-R expression. LDL-R on mononuclear cells were quantified by flow cytrometry. RESULTS: Among the 39 HIV infected patients, 14 patients had a lipodystrophy (LD). Patients with LD had significantly higher levels of triglyceride (TG) and insulin resistance compared to patients without LD. There was no significant difference in LDL-R count between patients with or without PI use. In contrast, LDL-R count was significantly lower in patients with LD compared with those without (8504 +/- 3901 vs. 13 200 +/- 4532, P = 0.001). There was no difference in LDL-R count between patients without LD and control subjects. Patients with LD had lower levels of DHEA compared to patients without LD. In HIV-infected patients, we found a significant correlation between LDL-R expression and TG (r = -0.32; P = 0.04) and LDL cholesterol (r = -0.33; P = 0.04). In contrast, we did not observe a correlation between DHEA level and LDL-R count or LDL cholesterol level. CONCLUSIONS: HIV-lipodystrophy is associated with a lower expression of LDL-R. This decreased expression of LDL-R seems independent of DHEA or insulin secretion.     

Hyperlipidemia in HIV-positive patients receiving antiretrovirals

OBJECTIVE: To assess the frequency of lipid abnormalities and treatment outcomes for hyperlipidemia in HIV-positive patients receiving antiretroviral (ARV) therapy as outpatients at a Veterans Affairs HIV clinic. METHODS: All patients monitored for at least 3 months were reviewed. Data collected included age, most recent CD4+ cell count and viral load, ARV history, and all fasting cholesterol, triglyceride, high-density lipoprotein (HDL), and low-density lipoprotein (LDL) values. The ARV therapy at the time of lipid readings was classified as including protease inhibitors (PI+) or not including them (PI-). Lipid values were compared with goals per national guidelines and risk factors. RESULTS: Male patients (n = 101) providing 210 lipid profiles were evaluated (median 2 per patient). Median age was 51 years. Fourteen patients were diabetic, 31 were hypertensive, and 6 patients had documented coronary disease. Mean cholesterol, triglycerides, and LDL values were significantly higher in PI+ (n = 50) compared with those of PI- patients (n = 51; p < 0.05). HDL values were not different between groups. Significantly more PI+ patients had lipid concentrations above recommended goals compared with PI- patients (17 vs. 7; p = 0.04). Six patients achieved lipid goals after following a low-fat diet (4 PI+). Fifteen subjects (11 PI+) were being treated with medications. Ten patients (67%) reached lipid goals, 2 had not reached goals (13%), and 3 (20%) were undergoing medication titration. CONCLUSIONS: Our HIV-infected patients had significantly higher cholesterol, triglyceride, and LDL values when PI+. In contrast to other reports, the majority of patients treated for lipid abnormalities achieved treatment goals.     

Improvement in insulin sensitivity and dyslipidemia in protease inhibitor-treated adult male patients after switch to atazanavir/ritonavir.

BACKGROUND: Treatment of human immunodeficiency virus (HIV) with protease inhibitors (PIs) is associated with insulin resistance, triglyceride-rich dyslipidemia, and fat redistribution. Atazanavir (ATV), a potent once-daily PI, has been recognized for its convenience to patients, and some studies describe improved lipid metabolism. However, its effects on insulin sensitivity have not been elucidated. We conducted this study to test the hypothesis that ATV improves insulin resistance and dyslipidemia. METHODS: We prospectively studied 9 HIV-infected men with dyslipidemia (median age, 53 years; baseline triglyceride level, >200 mg/dL) on stable PI-containing antiretroviral therapy who elected to change PI therapy to ritonavir-boosted ATV therapy, dose of 300/100 mg. We measured insulin resistance at baseline and after 12 weeks of therapy using a hyperinsulinemic euglycemic clamp (insulin dose, 200 mU/m minute). Fasting lipid profiles and body composition (whole-body dual energy x-ray absorptiometry) were also measured at baseline and after 12 weeks. RESULTS: All 9 patients completed the study and maintained undetectable viral loads (<50 copies/mL) and stable CD4 counts. After 12 weeks, insulin sensitivity significantly improved (+28%; P = 0.008) in all patients. Triglyceride levels also improved. CONCLUSIONS: Using the gold-standard euglycemic clamp, ritonavir-boosted ATV therapy improved PI-induced insulin resistance among dyslipidemic HIV-infected men on PI-based antiretroviral therapy. These findings were not attributable to a change in body weight and provide further evidence for ATV's unique metabolic profile among the PIs.     

Evaluation of cardiovascular risk factors in HIV-1 infected patients using carotid intima-media thickness measurement

BACKGROUND: Highly active antiretroviral therapies (HAART) in HIV-infected patients are often associated with lipodystrophy syndrome and metabolic disorders. Atherogenic lipid profile could expose these patients to atheromatous cardiovascular disease. We describe carotid artery intima-media thickness (IMT), a surrogate marker of atherosclerosis, according to HIV status, antiretroviral treatment, lipodystrophy and conventional cardiovascular risk factors. METHOD: In a multicenter prospective cohort study we have surveyed HIV-infected subjects with a carotid IMT measurement by B-mode ultrasonography. We collected information on lipodystrophy clinical manifestations, age, gender, body mass index (BMI), smoking habits, alcohol intake, systolic blood pressure, HIV transmission category, AIDS stage, type and duration of HAART, CD4+ cell count, plasma HIV-1 RNA, glucose, insulin, total cholesterol and homocysteine. RESULTS: Four hundred and twenty-three HIV-infected patients were studied. The median carotid IMT measurement was 0.54 mm (range: 0.50-0.60). Lipodystrophy syndrome was diagnosed in 161 HIV-infected patients (38.1%). In univariate linear regression, IMT was significantly higher (P<0.05) with older age, male gender, higher body mass index, higher waist-to-hip ratio, increased systolic blood pressure, total cholesterol, glucose disorders and homocysteine, regular smoking and alcohol consumption, lipodystrophy and HAART. In a multivariate analysis, the effect of lipodystrophy and HAART disappeared after adjustment for other cardiovascular risk factors. CONCLUSIONS: It was concluded that only conventional cardiovascular risk factors are independently associated with increased IMT in HIV-infected patients.     

Improvement in dyslipidaemia after switching stavudine to tenofovir and replacing protease inhibitors with efavirenz in HIV-infected children

OBJECTIVE: To assess the impact on immunological, virological and metabolic parameters of replacing protease inhibitors (PIs) with efavirenz and replacing stavudine with tenofovir in HIV-infected children. METHODS: A 48-week prospective evaluation of 28 HIV-infected children, with stable undetectable HIV-1 loads, who were taking highly active antiretroviral therapy (HAART) containing lamivudine, stavudine and a PI. Individuals were randomized to switch PI to efavirenz and stavudine to tenofovir at baseline (Group 1) or at week 24 (Group 2). Patient assessment included: clinical evaluation, viral load, CD4+ T-cell count, fasting blood levels and urine samples. RESULTS: All individuals maintained HIV RNA <50 copies/ml and unchanged CD4+ T-cell count through week 48. In Group 1 individuals, a significant decrease in cholesterol (P < 0.05), cholesterol:high-density lipoprotein (HDL) ratio (P < 0.01) and triglycerides (P < 0.05) was observed 24 and 48 weeks after the switch of HAART. The percentage of Group 1 children with increased cholesterol and triglycerides markedly decreased over the study period (from 43% to 0% and from 36% to 7%, respectively). In Group 2 individuals, unchanged lipids in the 24 weeks prior to the switch of HAART and a significant improvement on cholesterol (P < 0.05), cholesterol:HDL ratio (P < 0.01) and triglycerides (P < 0.05) were observed 24 weeks after the switch of HAART. The percentage of Group 2 children with increased cholesterol and triglycerides markedly decreased 24 weeks after the switch of HAART (from 46% to 7% and from 54% to 0%, respectively). Proteinuria and glucosuria were not detected in any individual. The mean values of serum creatinine, serum phosphorus, serum bicarbonate, estimated glomerular filtration rate, urinary microalbumin/creatinine, alpha-1-microglobulin/creatinine ratio and maximal tubular phosphate reabsorption remained unchanged in both groups. CONCLUSIONS: In HIV-infected children, switching PI to efavirenz and stavudine to tenofovir is virologically and immunologically safe, is not associated with renal impairment and provides a significant improvement in lipid profile.     

Evaluation of cardiovascular risk factors in HIV-1 infected patients using carotid intima-media thickness measurement

BACKGROUND. Highly active antiretroviral therapies (HAART) in HIV-infected patients are often associated with lipodystrophy syndrome and metabolic disorders. Atherogenic lipid profile could expose these patients to atheromatous cardiovascular disease. We describe carotid artery intima-media thickness (IMT), a surrogate marker of atherosclerosis, according to HIV status, antiretroviral treatment, lipodystrophy and conventional cardiovascular risk factors. METHOD. In a multicenter prospective cohort study we have surveyed HIV-infected subjects with a carotid IMT measurement by B-mode ultrasonography. We collected information on lipodystrophy clinical manifestations, age, gender, body mass index (BMI), smoking habits, alcohol intake, systolic blood pressure, HIV transmission category, AIDS stage, type and duration of HAART, CD4 + cell count, plasma HIV-1 RNA, glucose, insulin, total cholesterol and homocysteine. RESULTS. Four hundred and twenty-three HIV-infected patients were studied. The median carotid IMT measurement was 0.54 mm (range: 0.50-0.60). Lipodystrophy syndrome was diagnosed in 161 HIV-infected patients (38.1%). In univariate linear regression, IMT was significantly higher (P < 0.05) with older age, male gender, higher body mass index, higher waist-to-hip ratio, increased systolic blood pressure, total cholesterol, glucose disorders and homocysteine, regular smoking and alcohol consumption, lipo dystrophy and HAART. In a multivariate analysis, the effect of lipodystrophy and HAART disappeared after adjustment for other cardiovascular risk factors. CONCLUSIONS. It was concluded that only conventional cardiovascular risk factors are independently associated with increased IMT in HIV-infected patients.     

Dyslipidaemia associated with antiretroviral therapy in HIV-infected patients

Highly active antiretroviral therapy (HAART) has had a significant impact on the natural history of human immunodeficiency virus (HIV) infection, leading to a remarkable decrease in its morbidity and mortality, but is frequently associated with clinical and metabolic complications. Fat redistribution or lipodystrophy, hypertriglyceridaemia, hypercholesterolaemia, insulin resistance and diabetes mellitus have been extensively reported in subjects treated with protease inhibitor (PI)-based antiretroviral regimens. In particular, dyslipidaemia occurs in up to 70-80% of HIV-infected individuals receiving HAART and can be associated with all the available PIs, although hypertriglyceridaemia appears to be more frequent in patients treated with ritonavir, ritonavir-saquinavir, or ritonavir-lopinavir. The potential long-term consequences of HAART-associated hyperlipidaemia are not completely understood, but an increased risk of premature coronary artery disease has been reported in young HIV-positive persons receiving PIs. Dietary changes, regular aerobic exercise and switching to a PI-sparing regimen may act favourably on dyslipidaemia. Lipid-lowering therapy is often required with statins or fibrates. The choice of hypolipidaemic drugs should take into account potential pharmacological interactions with antiretroviral agents.     

Management of dyslipidaemia in HIV-infected patients receiving antiretroviral therapy

Dyslipidaemia associated with the treatment of HIV infection, particularly with the use of protease inhibitors (PIs), can raise cholesterol and triglyceride (TG) levels to the thresholds indicated for intervention. Recent evidence from epidemiological studies has shown that there are correlations between antiretroviral drug use and increased risks for, and incidences of, cardiovascular disease, including myocardial infarction and coronary heart disease. The primary goals of dyslipidaemia therapy for HIV patients are reductions of both low-density lipoprotein cholesterol (LDL-C) and markedly elevated TG levels. Dietary strategies and exercise programs may be tried, although these have shown inconsistent results. The two options for drug therapy are switching antiretroviral agents and using lipid-lowering drugs. Each approach is associated with advantages and limitations, and the need to maintain viral suppression must be balanced with the need to treat abnormal lipid levels. Most drug switches replace the PI component with drugs from another antiretroviral class. Selection of drug therapy for lipid lowering depends on the type of dyslipidaemia predominating and the potential for drug interactions. The use of the statins pravastatin and atorvastatin is recommended for the treatment of patients with elevated LDL-C levels and gemfibrozil or fenofibrate for patients with elevated TG concentrations. Development of new PIs with more favourable effects on the lipid profile should be of benefit.     

Risk factors for lipodystrophy in the CISAI cohort.

PURPOSE: This study set out to describe the frequency of lipodystrophy, and identify its risk factors, in HIV-positive patients treated with HAART containing at least one protease inhibitor (PI). We analyzed the data collected in the CISAI study. METHODS: The CISAI is a multicenter cohort study that has enrolled 1480 patients. We assessed whether patients had lipodystrophy at a medical visit, with follow-up visits by the same physician at least every 2 months, and also on the basis of patients' own reports. RESULTS: The lipodystrophy syndrome was detected in about 25% of the patients. Multivariate analysis showed the risk of lipodystrophy was correlated with female sex (RR 1.5; 95% confidence interval, CI, 1.2-2.1), with older age, with homosexuality (RR 1.5; 95% CI 1.0-2.4), with overt disease (RR 1.4; 95% CI 1.1-1.8) and with the duration of treatment before entering this study. The RR for ritonavir was higher than for the other PI (RR 1.4; 95% CI 0.9-1.9). Among patients receiving concomitant antiretroviral therapy the risk of lipodystrophy was greater with stavudine (RR 1.7; 95% CI 1.3-2.3). CONCLUSIONS: The study confirmed the high frequency of the lipodystrophy syndrome among patients treated with PI.     

Changes in leptin serum levels in HIV-infected children receiving highly active antiretroviral therapy

Highly active antiretroviral therapy (HAART) has significantly improved the prognosis of HIV(+) in children. Human immunodeficiency-associated lipodystrophy syndrome (HALS) is a side effect of HAART seen predominantly in adults and less often in children. Leptin is a protein thought to play an important role in body composition and has been shown to have immunomodulatory effects. We retrospectively studied serum levels of leptin in a cohort of eight HIV-infected children followed prospectively before and during HAART and investigated whether there is a correlation of these levels with the clinical, immunological, viral or nutritional changes observed during treatment in these children. None of our children developed HALS. In this small cohort of children, we found that serum leptin levels were appropriate to the nutritional status of the patient and that leptin/BMI increased in patients who responded to HAART. In conclusion, in HIV(+) children during HAART, leptin levels are related to the nutritional status of the child.     

Heart positive: design of a randomized controlled clinical trial of intensive lifestyle intervention, niacin and fenofibrate for HIV lipodystrophy/dyslipidemia

Dyslipidemia and insulin resistance occur in a large proportion of HIV-infected patients treated with highly active antiretroviral therapy (HAART); anthropomorphic changes, such as lipoatrophy and central obesity, occur in a subset of patients. This cluster of clinical features, which is termed HIV lipodystrophy, places patients at increased risk for cardiovascular disease. Currently, there is no consensus on the appropriate therapy for the management of HIV lipodystrophy for which the underlying defects are enhanced lipolysis, impaired fat oxidation, increased hepatic VLDL-triglyceride synthesis and secretion, and impaired disposal of intestinally-derived lipoprotein-triglycerides. We describe the design of a randomized, placebo-controlled trial to compare the effects of usual care to diet, exercise and lipid-lowering drugs on lipid profiles of patients with HIV lipodystrophy. The trial will randomize 200 patients into five groups. Outcomes of usual care, diet and exercise alone or in combination with niacin, fenofibrate or both medications will be compared after six months. Unique aspects of the design include an interactive Internet Diet Management system to increase ATP-III recommended dietary compliance for metabolic syndrome, and a supervised program of aerobic and resistance exercises. The study is powered to detect a 20% decrease in triglycerides with the lifestyle intervention and an additional 20% improvement with the addition of niacin and/or fenofibrate. Secondary outcomes include assessment of lipid profile changes, LDL and HDL particle size, plasma cholesterol ester transport protein activity, visceral and subcutaneous fat distribution, glucose tolerance, insulin resistance, and leptin and adiponectin levels.     

Highly active antiretroviral therapy-associated metabolic syndrome: pathogenesis and cardiovascular risk

The introduction of highly active antiretroviral therapy (HAART) has significantly modified the course of HIV disease, with longer survival and improved quality of life of HIV-infected subjects. However, HAART regimens, especially those including protease inhibitors (PIs) have been shown to cause in a high proportion of HIV-infected patients a metabolic syndrome that may be associated with an increased risk of cardiovascular disease (about 1.4 cardiac events per 1,000 years of therapy according to the Framingham score). Metabolic features associated with somatic changes (lipodystrophy/lipoatrophy) include dyslipidemia (about 70% of patients), insulin resistance (elevated C-peptide and insulin), type 2 diabetes mellitus (8%-10% of the patients), hypertension (up to 75% of patients), coagulation abnormalities (25% of patients), lactic acidemia, and elevated hepatic transaminases (nonalcoholic steatohepatitis). HAART-associated metabolic syndrome is an increasingly recognized clinical entity. A better understanding of the molecular mechanisms responsible for this syndrome will lead to the discovery of new drugs that will reduce the cardiovascular risk in patients under HAART. A careful stratification of the cardiovascular risk and cardiovascular monitoring of patients under HAART is needed according to the most recent clinical guidelines.     

Serum adiponectin and metabolic parameters in HIV-1-infected patients after substitution of nevirapine for protease inhibitors

BACKGROUND: In the context of HIV infection and antiretroviral therapy, adiponectin concentrations have been shown to be related to lipodystrophy, metabolic alterations and HIV-protease inhibitor (PI) use. The replacement of PI by nevirapine has improved the lipid profile of patients under antiretroviral therapy. The aim of the present study was to examine whether adiponectin concentration or insulin sensitivity level correlate with the modifications of lipid parameters after the switch of PI by nevirapine. MATERIAL AND METHODS: The evolution of metabolic parameters before and after 6 months of substitution of nevirapine for protease inhibitors was evaluated in a cohort of 55 HIV-1 infected patients. Adiponectin concentration, insulin sensitivity, lipid profile, cholesterol ester transfer protein (CETP) mass concentration and triglyceride enrichment of HDL were determined before and after the replacement of PI by nevirapine. Insulin sensitivity was evaluated by the HOMA model assessment. RESULTS: Twenty-four weeks of treatment with nevirapine improved significantly the lipid profile with a significant reduction of apoB (from 0.98 to 0.92 g L(-1); P = 0.005) and triglyceride (from 2.02 to 1.66 mmol L(-1); P = 0.02). HDL cholesterol and apoA1 increased significantly (from 0.99 to 1.19 mmol L(-1); P = 0.001 and from 1.40 to 1.57 g L(-1); P < 0.001, respectively). The triglyceride enrichment of HDL significantly decreased after the replacement of PI by nevirapine (from 0.248 +/- 0.092 to 0.213 +/- 0.093; P = 0.003). At baseline, and after 24 weeks of nevirapine treatment, we observed significant correlations between adiponectin level and lipid parameters [(HDL-cholesterol (r = 0.66, P = 0.001 and r = 0.69, P = 0.001); triglycerides (r = -0.42, P = 0.002 and r = -0.57, P = 0.001), and triglyceride enrichment of HDL (r = -0.43, P = 0.005 and r = -0.53, P = 0.005)]. Twenty-four weeks of treatment with nevirapine did not significantly change adiponectin concentrations (from 984 to 1086 micro g L(-1), P = 0.22), CETP mass and insulin sensitivity. CONCLUSION: This study shows that even though a strong correlation was found between adiponectin and some metabolic parameters at baseline and after 24 weeks of treatment by nevirapine, the improvement of lipid profile observed after the replacement of PI by nevirapine was not in relation to the change of plasma adiponectin concentration. The significant decrease of triglyceride enrichment of HDL after the replacement of PI by nevirapine probably leads to a decreased catabolism of HDL lipoprotein, and consequently explains the increase of plasma HDL concentration observed in this study.     

血药浓度监测在儿童艾滋病患者抗病毒治疗依从性评价中的应用

目的 探讨血药浓度监测在儿童艾滋病患者抗病毒治疗依从性评价中的应用价值.方法 收集2009年3-10月河南省上蔡县CDC诊治的87例患儿连续3次随访的治疗相关信息及261份血浆标本,建立高效液相色谱-质谱联用的方法,测定血浆中抗病毒药物浓度.对治疗方案、患儿年龄、性别、父母情况、治疗经历和治疗时间等可能影响依从性的相关因素采用单因素Logistic回归分析.结果 以血药浓度是否低于LLTR 1000 ng/ml为标准判断患者是否漏服药物,发现28份标本血药浓度

Abstract：

Objective To evaluate the application of plasma drug monitoring in pediatric HIV/AIDS patient antiretroviral therapy adherence monitoring.Methods Totally 261 plasma samples and related information were collected from three consecutive follow-up visits of 87 HIV-infected children treated in Shangcai county CDC of Henan province from March to October 2009.The plasma concentrations of antiretroviral drugs were measured by a developed high performance liquid chromatography-mass spectrometry method.Potential adherence influencing factors, such as regimen, age, gender, parent conditions, previous ART exposure and therapy duration, were analyzed by univariate logistic regression.Results Plasma concentration of antiretroviral drugs lower than LLTR (1 000 ng/ml) was the criteria to identify missed dose.The concentrations of 28 plasma samples were lower than LLTR, which meant missing dose.There were 17 patients (19.5%) with their concentrations lower than LLTR at least once in three follow-up visits.Logistic regression analysis of adherence related factors showed that compared with the children whose parents were both alive, the children whose mother and (or) father died were more likely to miss dose.The odds ratio was 4.13(95% credibility interval:1.37-12.46, P values was 0.012).Conclusions HIV-infected children have adherence problems when receiving antiretroviral therapy.Plasma therapeutic drug monitoring can be one of the effective methods to monitor the adherence.     

The influence of HIV infection and antiretroviral therapy on the mitochondrial membrane potential of peripheral mononuclear cells

OBJECTIVES: Clinical disorders occurring in HIV-infected patients on antiretroviral therapy (ART) have been linked to mitochondrial dysfunction, for example, lactic acidosis and lipodystrophy. Mitochondrial membrane potential (delta psi m) is the most direct measure of the state of energization of the mitochondria. We analysed delta psi m, of peripheral blood mononuclear cells (PBMCs) in HIV-negative, healthy subjects (n=8), HIV-infected, treatment-naive patients (n=30), and HIV-infected patients on ART (n=58). The influence of ART was analysed in six patients who started their first regimen. METHODS: The delta psi m of PBMC was measured by flow cytometry using the dye JC-1. RESULTS: The delta psi m was significantly lower in HIV-infected patients than in HIV-negative controls. This difference was detected in both treated (P = 0.0001) and untreated patients (P = 0.001). The delta psi m of PBMCs was highly correlated with CD4+ T-cell count in therapy-naive patients (P = 0.002, r = 0.546) and in treated patients (P = 0.028, r = 0.288). The delta psi m increased significantly in therapy-naive patients after starting ART (P = 0.001). Patients with lipoatrophy had significantly lower delta psi m than patients without lipodystrophy or with lipohypertrophy (P = 0.023). CONCLUSIONS: In HIV-infected persons delta psi m is significantly reduced. Patients with lipoatrophy have significantly reduced delta psi m. This is the first study showing that the delta psi m of PBMCs is highly correlated with CD4+ T-cell count in HIV infection.