Cardiovascular Risk Vital For HIV Patients
Antiretroviral medications have dramatically reduced the overall death rate among patients with the human immunodeficiency virus (HIV), but those same patients may now face an increased risk for cardiovascular disease (CVD), according to a group of experts who gathered to review the unique CVD risks experienced by people living with HIV and AIDS.
The group notes that many patients infected with HIV have cholesterol abnormalities which may be side effects from the antiretroviral medications, effects of the virus, or both. Also common in this population are traditional risk factors for cardiovascular disease such as insulin resistance, diabetes, the tendency to carry excess weight in the mid-section, kidney abnormalities and more, which might be influenced by the HIV drug regimen or the virus itself. In addition, there is a high prevalence of smoking in HIV-infected individuals - some studies estimate 50 percent or more of them smoke.
Scientists and healthcare providers convened in June 2007 for the State of the Science Conference: Initiative to Decrease Cardiovascular Risk and Increase Quality of Care for Patients Living with HIV/AIDS, a joint effort of the American Heart Association and the American Academy of HIV Medicine. The conference proceedings are published online in Circulation: Journal of the American Heart Association and Journal of Acquired Immune Deficiency Syndrome.
During the two and one-half day meeting, participants assessed the association among HIV, antiretroviral therapy (ART) and cardiovascular disease.
"It is important to stress that this report by no means diminishes the importance of antiretroviral therapy. Rather, it is a call to physicians and others who care for people with HIV to carefully evaluate them for cardiovascular risk because the literature shows that cardiovascular disease now accounts for a higher proportion of the deaths among HIV patients in this era of highly active antiretroviral therapy," said Steven Grinspoon, M.D., meeting co-chair and professor of medicine at Harvard Medical School and Massachusetts General Hospital in Boston, Mass.
Among the group's key findings:
* The risk for heart attack is 70 percent to 80 percent higher among people with HIV compared to those who do not have HIV, although the absolute risk still remains low for younger patients.
* Having HIV is associated with increases in two important risk factors for heart disease:
- low levels of HDL cholesterol (high-density lipoproteins or "good" cholesterol) and
- elevated levels of triglycerides (a type of blood fat).
"There are studies now that suggest that even young children with HIV on these medicines have early development of cardiovascular risk factors," Grinspoon said.
* Large studies suggest that the cardiovascular disease increase among HIV-infected patients is associated with specific metabolic abnormalities linked to antiretroviral therapy, including diabetes, as well as traditional risk factors such as smoking.
"We've often ignored traditional cardiovascular risks in HIV patients because we thought they would die from the virus," Grinspoon said. "But today they're living, thanks to these therapies, and we need to assess their risk factors and advise them about their health as we would the non-HIV patient."
* While it's easy to assume that long-term ART use could further increase cardiovascular risk for these patients, the research suggests that uninterrupted ART treatment may reduce cardiovascular risk.
"We think that going on and off these medications may cause more harm than good, and further research is needed on this important question," Grinspoon said.
* It's important to stratify CVD risk in HIV-infected patients. Clinicians can use existing general risk stratification algorithms, such as the Framingham Risk Score, to measure HIV patients' risk for heart disease, as this algorithm performs reasonably well in the HIV population although it does not incorporate specific HIV factors. Development of well-validated HIV specific risk-prediction equations is an important future research priority, Grinspoon said.
* HIV patients on antiretroviral therapy also tend to have higher risk for non-atherosclerotic heart disease, including pulmonary hypertension (elevated blood pressure in the pulmonary arteries, associated with the lungs) and pericardial disease (inflammation of the sac that surrounds the heart).
* Whether the elevated risk for heart disease is more attributed to the disease, ART or an interaction between the two is not yet clear, Grinspoon said.
Future research to answer this and other questions, as well as distributing the initiative's initial findings to HIV and other providers, are the next steps, he said.
"The members of the initiative recommend that strategies to prevent cardiovascular disease in HIV-infected patients should focus on reducing traditional risk factors, as well as HIV and ART-specific risk factors," Grinspoon said. "In essence, it means practicing good preventive medicine with all patients, including those who have HIV."