Widespread use of antiretroviral therapy has caused a remarkable decline in rates of morbidity and death related to acquired immunodeficiency syndrome (AIDS) and has effectively made human immunodeficiency virus (HIV) infection a manageable—although not yet curable— chronic condition. And as the HIV-infected population on antiretroviral therapy ages, the prevalence of chronic conditions (eg, cardiovascular disease, hepatic disease, pulmonary disease, non-AIDS cancers) and deaths attributable to these conditions have also increased. 1
Many of the traditional risk factors for cardiovascular disease in the general population, including smoking, dyslipidemia, and diabetes, are common in HIV-infected patients, and HIV infection itself independently increases the risk of coronary heart disease. In addition, different antiretroviral combinations can contribute, in varying degrees, to changes in lipid levels and insulin resistance, further increasing coronary risk.
Ultimately, however, the immunologic benefits of antiretroviral therapy for individual patients far exceed the modest increase in cardiovascular risk associated with certain regimens. In most cases, careful selection of the initial antiretroviral regimen and the addition of lipid-lowering or glucose-controlling medications (with close attention to drug interactions) can effectively manage the metabolic changes associated with antiretroviral therapy and obviate any premature modification of virologically suppressive regimens.
TRADITIONAL CARDIAC RISK FACTORS IN HIV PATIENTS
The risk of coronary heart disease in HIV patients is influenced mostly by traditional factors such as age, smoking, diabetes, and dyslipidemia, including high levels of total cholesterol and low-density lipoprotein cholesterol (LDL-C) and low levels of high-density lipoprotein cholesterol (HDL-C). 2
In various large cohorts, HIV-infected men had a higher prevalence of smoking, 3 a lower mean HDL-C level, 3,4 and a higher mean triglyceride level 3,4 than men without HIV infection, placing them at greater risk of coronary heart disease. However, even after adjusting for traditional risk factors, rates of atherosclerosis are still higher in people who are infected with HIV than in those who are not. 5
EFFECT OF HIV INFECTION ON CORONARY RISK
HIV infection has been shown to increase coronary risk.
In the Kaiser Permanente database, 6 HIV-positive patients had a significantly higher rate of hospitalizations for coronary heart disease than did people who were not infected.
Similarly, in a cohort study of almost 4,000 HIV-infected patients and more than 1 million controls, the risk of acute myocardial infarction was 75% higher for HIV-positive patients than for HIV-negative patients, even after adjusting for sex, race, hypertension, diabetes, and dyslipidemia. 5
The Fat Redistribution and Metabolism (FRAM) cross-sectional study 7 showed that HIV infection was associated with greater carotid intima media thickness, an established marker of atherosclerosis, independently of traditional risk factors and to virtually the same degree as smoking and male sex.
Other studies of subclinical atherosclerosis in HIV patients have yielded disparate results, likely because of differences in study design, methods of measuring carotid thickness, and characteristics of the study populations (eg, prevalence of cardiovascular risk factors and stage of HIV disease). However, a meta-analysis of six prospective cohort studies, three case-control studies, and four cross-sectional studies confirmed that HIV patients had slightly but statistically significantly greater carotid intima media thickness than HIV-negative people. 8