Management of dyslipidemia in patients with HIV disease

New options in the treatment of lipid disorders in HIV-infected patients

Since the introduction of HAART, there was a remarkably change in the natural history of HIV disease, leading to a notable extension of life expectancy, although prolonged metabolic imbalances could significantly act on the longterm prognosis and outcome of HIV-infected persons, and there is an increasing concern about the cardiovascular risk in this population. Current recommendations suggest that HIV-infected perons undergo evaluation and treatment on the basis of the Third National Cholesterol Education Program Expert Panel on Detection, Evaluation and Treatment of High Blood Cholesterol in Adults (NCEP ATP III) guidelines for dyslipidemia, with particular attention to potential drug interactions with antiretroviral agents and maintenance of virologic control of HIV infection. While a hypolipidemic diet and physical activity may certainly improve dyslipidemia, pharmacological treatment becomes indispensable when serum lipid are excessively high for a long time or the patient has a high cardiovascular risk, since the suspension or change of an effective antiretroviral therapy is not recommended. Moreover, the choice of a hypolipidemic drug is often a reason of concern, since expected drug-drug interactions (especially with antiretroviral agents), toxicity, intolerance, effects on concurrent HIV-related disease and decrease patient adherence to multiple pharmacological regimens must be carefully evaluated. Often the lipid goals of patients in this group are not achieved by the therapy recommended in the current lipid guidelines and in this article we describe other possibilities to treat lipid disorders in HIV-infected persons, like rosuvastatin, ezetimibe and fish oil.

Predictive factors of hyperlipidemia in HIV-infected subjects receiving lopinavir/ritonavir

We studied 382 multiexperienced HIV-infected patients followed up for > or =3 months after starting lopinavir/ritonavir (LPV/r) to identify the factors predicting hypertriglyceridemia and high non-HDL cholesterol levels (triglycerides > or =200 mg/dl and/or non-HDL cholesterol > or =190 mg/dl) after 6 and 12 months of LPV/r exposure. The predictors of hypertriglyceridemia were higher baseline triglyceride levels [OR: 2.28 (95% CI: 1.67-3.12) for each additional 100 mg/dl; p = 0.001], the total duration of antiretroviral treatment [OR: 1.26 (95% CI: 1.12-1.41) for each additional year; p = 0.01], CDC stage C (OR: 2.06; 95% CI: 1.24-3.88; p = 0.02), and male gender (OR: 2.52; 95% CI: 1.42-4.74; p = 0.02); intravenous drug abusers seem less likely to develop the event (OR: 0.52; 95% CI: 0.37-0.92; p = 0.03). The predictors of high non-HDL cholesterol levels were higher baseline levels [OR: 3.92 (95% CI: 1.92-6.24) for each additional 100 mg/dl; p = 0.001) and the combination of NRTIs and NNRTIs with LPV/r (OR: 1.83; 95% CI: 1.10-3.69; p = 0.03). The 75 patients stopping LPV/r showed a significant reduction in median triglyceride and non-HDL cholesterol levels after 3 months of 39 mg/dl and 20 mg/dl (p = 0.01 for both), respectively. Patients with high triglyceride and non- HDL cholesterol levels at the start of LPV/r treatment are at higher risk of developing hyperlipidemia.

HIV-related lipodystrophy and related factors

As new therapies for HIV infection have been developed, some of the clinical focus related to AIDS and HIV infection has shifted from acute care, to more chronic issues. Some of these new clinical issues seem related to the HIV infection itself, while others seem to be side effects of therapeutic efforts. Metabolic abnormalities, such as dyslipidemia, insulin resistance, and lipodystrophy (LD) have been observed. The clinical importance of these is demonstrated by the increased prevalence of cardiovascular disease and diabetes in HIV infected persons. LD is a general term used to describe varying degrees of fat redistribution, including lipoatrophy and lipohypertrophy, in different body regions. Though LD was observed in persons with HIV infection before highly active treatment regimens were developed, the prevalence of LD has seemingly increased drastically with the widespread use of more active therapies. It has been postulated that protease inhibitors (PI), especially, are linked to the development of LD. This review will assess the epidemiologic information related to HIV-associated LD, and related metabolic syndromes. In addition, potential mechanisms accounting for these syndromes will be reviewed. In general, the available data do not define a single, definable etiology or mechanism explaining these clinical conditions, but suggest that these conditions are caused by a complex interaction potentially involving such things as the side effects of medications, alteration of immune function, and individual subject characteristics, such as body weight and baseline lipid level.

Risk of Metabolic Abnormalities in Patients Infected with HIV Receiving Antiretroviral Therapy that Contains Lopinavir‐Ritonavir

The evolution of fasting glucose, triglyceride, and total and high-density lipoprotein (HDL) cholesterol level and the factors associated with development of clinically significant abnormalities in these metabolic parameters at 6 months were assessed in 353 consecutive human immunodeficiency virus (HIV)-infected patients who were receiving antiretroviral therapy containing lopinavir-ritonavir. Although glucose and HDL cholesterol levels did not change, triglyceride and total cholesterol levels significantly increased (P<.0001 for each), as did the proportion of patients with a triglyceride level of >400 mg/dL and a total cholesterol level of >240 mg/dL (P=.002). A baseline triglyceride level of >400 mg/dL and a baseline total cholesterol level of >240 mg/dL were identified as independent factors predicting clinically significant hypertriglyceridemia and hypercholesterolemia, respectively, at 6 months. These findings may have clinical implications when the therapeutic option of lopinavir-ritonavir is considered.

HIV infection and advanced age emerging epidemiological, clinical, and management issues

While the mean age of HIV/AIDS patients at first diagnosis is progressively rising, no updated epidemiological estimates, controlled clinical data, and randomized therapeutic trials, are available regarding clinical and laboratory response to antiretroviral therapy, safety of anti-HIV compounds and their associations, potential drug-drug interactions, short- and long-term toxicity, consequences on underlying disorders, or interactions with concomitant pharmacological regimens, in the elderly. The life expectancy of HIV-infected persons treated with highly active antiretroviral therapy (HAART) now approximates that of general population matched for age, while also AIDS definition itself has lost most of its epidemiological and clinical significance, thanks to the immunoreconstitution resulting from the large-scale use of potent HAART regimens. The increased survival of HIV-infected patients, the late recognition of other subjects with missed or delayed diagnosis are responsible for a further expected rise of mean age of HIV-infected individuals, so that the patient population aged 60-70 years or more is expected to increase in coming years. Unfortunately, the majority of therapeutic trials involving antiretroviral therapy, as well as antimicrobial chemoprophylaxis for AIDS-related opportunistic complications, have advanced age and/or concurrent end-organ disorders among main exclusion criteria, or the design of these studies does not allow to extrapolate data regarding older patients, compared with younger ones. The very limited data presently available seem to demonstrate that HAART has a virological efficacy in the elderly comparable with that of younger adults, but immunological recovery is often slower and blunted, although several studies clearly demonstrated that thymic function is preserved until late adult age. When facing an HIV-infected patient with advanced age, health care givers have to pay careful attention to eventual end-organ disorders, all possible pharmacological interactions, overlapping toxicity due to concurrent drug administration. All these issues may significantly interfere with HAART activity, patient's adherence to prescribed medications, and frequency and severity of untoward effects. The guidelines of antiretroviral therapy and those of treatment and prophylaxis of AIDS-related diseases deserve appropriate updates, paralleling the increasing mean age of HIV-infected population. Moreover, epidemiological figures need an increased focus on older age, while clinical trials specifically targeting on the elderly population are mandatory to have reliable data on all aspects of HAART administration in advanced age.

Hyperlipidaemia in patients with HIV-1 infection receiving highly active antiretroviral therapy: epidemiology, pathogenesis, clinical course and management

A wide range of abnormalities of lipid metabolism have been recently described in HIV-infected patients receiving a protease inhibitor (PI)-based highly active antiretroviral therapy, including hypertriglyceridaemia and hypercholesterolaemia. The increase of plasma lipid concentrations may involve up to 70-80% of HIV-positive subjects treated with a PI-containing regimen and are frequently (but not always) associated with the fat redistribution or the lipodystrophy syndrome. Multiple pathogenetic mechanisms by which antiretroviral agents lead to dyslipidaemia have been hypothesized, but they are still controversial. The potential clinicopathological consequences of HIV-associated hyperlipidaemia are not completely known, but several anecdotal observations report an increased risk of premature coronary artery diseases in young HIV-positive individuals receiving PIs, besides peripheral atherosclerosis and acute pancreatitis. A limited-to-significant improvement of increased triglyceride and cholesterol plasma levels was described in patients who replaced PIs with nevirapine, efavirenz or abacavir, but the risks of long-term toxicity and virological relapse of this treatment switching are not completely defined. A hypolipidaemic diet and regular physical exercise may act favorably on dyslipidaemia, but pharmacological therapy becomes necessary when hyperlipidaemia is severe or persists for a long time. The choice of hypolipidaemic drugs is problematic because of potential pharmacological interactions with antiretroviral compounds and other antimicrobial agents, associated with an increased risk of toxicity and intolerance. Statins are considered the first-line therapy for the PI-related hypercholesterolaemia, while fibrates are the cornerstone of drug therapy when predominant hypertriglyceridaemia is of concern.

Incidence of hyperlipidaemia in a cohort of 212 HIV-infected patients receiving a protease inhibitor-based antiretroviral therapy

Two hundred and twelve HIV-positive patients who started a new protease inhibitor (PI)-based antiretroviral regimen between January 1998 and December 2000 in our tertiary care centre were prospectively followed-up during a 12-month study period, in order to assess the incidence of hyperlipidaemia and related clinical adverse events. At the end of 1-year follow-up, PI-containing antiretroviral treatment led to a statistically significant increase in serum triglyceride levels (P<0.005) and total and LDL-cholesterol levels (P<0.05). The overall incidence of hypertriglyceridaemia and hypercholesterolaemia was 38.2 and 25%, respectively. The incidence of increased serum triglyceride levels was significantly higher in patients treated with ritonavir (66.6%) or lopinavir/ritonavir (60.7%), compared with other PIs (P<0.04). Clinical adverse events possibly related to the hyperlipidaemia (such as cardiovascular diseases or acute pancreatitis) were not observed during the entire 12 months study period. In conformity with other previously published studies, the very high incidence of hyperlipidaemia during a PI-based therapy recognised in our work raises a big concern about its potential clinico-pathological consequences and the most convenient pharmacological management of these metabolic imbalances.

Statins and fibrates for the treatment of hyperlipidaemia in HIV-infected patients receiving HAART

OBJECTIVES

The aim of our work is to evaluate the role of statins and fibrates in the management of hyperlipidaemia in HIV-infected patients receiving highly active antiretroviral therapy.

DESIGN

Open-label, randomized, prospective study of the efficacy and safety of bezafibrate, gemfibrozil, fenofibrate, pravastatin and fluvastatin as pharmacologic treatment for protease inhibitor-related dyslipidaemia.

METHODS

Plasma lipid levels of 656 HIV-infected patients who referred to our tertiary care centre and were on protease inhibitor-based antiretroviral therapy for at least 12 months have been evaluated. All patients had HIV viral load < 50 copies/ml and presented with hypertriglyceridaemia of at least 6 months duration that was unresponsive to a hypolipidaemic diet; all have been treated with bezafibrate, gemfibrozil, fenofibrate, pravastatin, or fluvastatin for 12 months.

RESULTS

Of the 656 patients observed 113 (17.2%) received pharmacological therapy, while seven patients were excluded from evaluation due to early drop-out. Of the 106 evaluable subjects, bezafibrate was used in 25 cases, gemfibrozil in 22, fenofibrate in 22, pravastatin in 19, and fluvastatin in 18. At the close of 1-year follow-up, fibrates led to a reduction of 40.7% and 21.9% versus baseline triglyceridaemia and cholesterolaemia, respectively (P < 0.001), and statins led to a reduction of 34.8% and 25.2% versus baseline triglyceride and total cholesterol levels, respectively (P < 0.001), without significant differences according to each different administered hypolipidaemic drug.

CONCLUSIONS

All administered statins and fibrates revealed a similar, significant efficacy in the treatment of diet-resistant hyperlipidaemia, and showed a favourable tolerability profile.

HIV disease and advanced age: an increasing therapeutic challenge

The mean age of patients at both first HIV detection and AIDS diagnosis is progressively rising over time. However, reliable epidemiological estimates, clinical data or controlled therapeutic and outcome figures are lacking for elderly patients, especially with regard to laboratory and clinical response to antiretroviral therapy, treatment tolerability, drug-drug interactions, short- and long-term toxicity, and interactions with underlying illnesses and concurrent pharmacological treatment. In fact, the large majority of randomised, controlled trials evaluating and comparing new antiretroviral drugs or anti-HIV therapeutic strategies, as well as antimicrobial treatment or chemoprophylaxis of HIV-related complications, either excluded patients with advanced age and/or concurrent disorders or did not offer substudies or detailed data analysis focusing on older patients compared with younger ones. The life expectancy of HIV-infected persons receiving highly active antiretroviral therapy (HAART) is now extended (approaching that of the general population), so that the definition of AIDS has lost its epidemiological and clinical significance thanks to the immune reconstitution resulting from potent antiretroviral therapy. However, an ever-increasing number of individuals aged > or =50 years with HIV infection is expected in the coming years, as a result of both increased survival of patients with treated disease and delayed recognition of individuals with occult HIV disease. The limited data available about combined antiretroviral therapy in the elderly seem to show an overlapping virological success rate but a slower and blunted immune recovery compared with younger patients. Thymic output, however, seems somewhat preserved even in adulthood and may contribute to the reconstitution of most of the quantitative and functional T cell abnormalities caused by HIV disease. More attention must be paid to underlying end-organ disorders, as well as expected pharmacological interactions and combined drug toxicity that may interfere with HAART efficacy and patients' compliance with recommended regimens and could lead to increased adverse effects. The available guidelines for antiretroviral treatment and therapy and prophylaxis of AIDS-related illnesses should be regularly updated and should include problems related to HIV disease in an aging population. Specific trials or substudies focusing on older people are warranted to obtain controlled data on all issues of antiretroviral therapy in the elderly, including time and mode of initiation, and modification and salvage HAART regimens. Antiretroviral drug dosage adjustment to take into account underlying pathological conditions or other pharmacological treatments is another emerging issue.