Protease Inhibitors Linked to Higher Risk of Heart Disease
A study presented yesterday at the XIV International AIDS Conference in Barcelona, Spain, contains the "strongest evidence so far for a causal link" between the use of protease inhibitors by HIV-positive people and an increased risk of heart disease, the Washington Post reports. The study, presented by Giorgio Barbarini, an epidemiologist at the University La Sapienza in Rome, followed 1,200 treatment-naive HIV-positive individuals over a period of three years. The group was randomly assigned a combination treatment regimen either containing or excluding a protease inhibitor. The majority of study participants were male and all were under the age of 48. At the end of the study period, the group that received protease inhibitors had recorded 23 new cases of heart disease -- 12 heart attacks and 11 cases of angina -- compared to two incidents of heart disease in the group that did not receive protease inhibitors. The factors most associated with heart disease were lipodystrophy, elevated cholesterol and triglyceride levels, smoking and elevated levels of the blood-clotting protein fibrinogen, a condition that often occurs in those who smoke. Eighty-seven percent of the original study group smoked at least 15 cigarettes a day.
Settling the Debate?
Researchers first began looking for a link between protease inhibitors and heart disease after doctors began noticing rises in cholesterol, triglycerides and blood sugar -- all signs of heart disease -- in many users after the drug's introduction in 1996. Previous research into a link had been inconclusive. The Post reports that although the Italian study's results are "unambiguous," they "aren't likely to settle the question" in the near future because it is not clear whether the drugs actually raise a user's risk of developing heart disease or merely "accelerate the emergence of heart disease in people who are already prone to it," as Barbarini suggested. Despite the apparent association, Dr. Jens Lundgren, a Danish expert on HIV and heart disease, urged patients to continue taking protease inhibitors, noting that the risk of developing heart disease was still "very small" compared to the "huge" benefits of the drugs. The introduction of protease inhibitors has helped decrease death rates in some populations from 25% to 2% per year (Brown, Washington Post, 7/11).
New England Journal of Medicine Pulls Heart-Related AIDS Study
In related news, the New England Journal of Medicine today retracted a 1998 heart-related AIDS study after it determined that a photo used in the study was taken from an eight-year-old study, Reuters Health reports. The photo had been inverted top to bottom and side to side but was determined to be the same photo taken from an AIDS-related study appearing in the American Journal of Cardiology in 1990. "When there's a piece of data that's been called into question, we have to assume that the whole data set is questionable," NEJM Executive Editor Gregory Curfman said (Reuters Health, 7/11).