Increased Risk of Heart Attacks Found in HIV Drugs

April 7, 2008

Many people with HIV take a combination of antiretroviral drugs. Concerns have been raised about the cardiovascular effects of long-term use of these drugs.

The HIV drugs abacavir and didanosine have recently been discovered to cause increased risk for heart attacks, according to a HealthDay article, as printed in The Washington Post last week. The study, conducted by The Lancet collected data from approximately 33,000 HIV patients. In response, the US Food and Drug Administration is now conducting a safety review of the potential risks of both drugs; recent data shows patients taking HIV drugs from GlaxoSmithKline and Bristol-Myers Squibb may have increased risk of heart attack.

The FDA also said data pooled from a 33,000-patient study of HIV patients showed those taking Glaxo's Ziagen and Bristol-Myers' Videx had a greater chance of heart attack than patients on other medications.

Many people with HIV take a combination of antiretroviral drugs, which include a protease inhibitor and a nucleoside reverse transcriptase inhibitor like abacavir or didanosine. Concerns have been raised about the cardiovascular effects of long-term use of these drugs. Patients from the Lancet study who discontinued use of these drugs saw a noticeable improvement in their health within 6 months.

For commonly used drugs called nucleoside reverse transcriptase inhibitors such as zidovudine, stavudine or lamivudine, the researchers found no association with an increased risk for heart attack.

However, the nucleoside reverse transcriptase inhibitors abacavir and didanosine were associated with an increased rate of heart attack, the researchers found. For patients taking abacavir, there was a twofold increased risk for heart attack. For those taking didanosine, the increased risk was about 50 percent.

For patients who stopped using these drugs, their risk for heart attack decreased within six months, Lundgren's group found.

James Sosman, MD, associate professor of medicine at the University of Wisconsin School of Medicine, noted that the use of antiretroviral drugs has replaced concerns about serious opportunistic infections in HIV patients with concerns about less serious risks like cardiovascular disease and diabetes.

"The most important thing for HIV patient is to control their HIV," Sosman says. "If they have excellent control with abacavir or didanosine, then you look for options to limit other risk factors. Patients not on HIV therapy have a higher risk of developing heart disease than people on HIV therapy.”