20 Jan Study Finds No Increased Heart Attack Risk in HIV Patients
Medical Research: What is the background for this study?
Dr. Klein: The prognosis for individuals living with HIV infection has dramatically improved with the availability of potent, well-tolerated and convenient antiretroviral therapies. HIV infection can now be viewed as a chronic, manageable condition with the life expectancy of successfully treated patients approaching that of uninfected individuals. As the focus of long-term HIV care has shifted from the managing opportunistic infections and cancers that were the hallmark of the early years of the HIV epidemic, increased attention is being directed at the consequences of treatment, immunodeficiency and chronic inflammation. One such complication is a reported increased risk of coronary artery disease. A recent report from Kaiser Permanente researchers in California offers some good news on this topic. For more than a decade, these investigators, led by Dr Daniel Klein, Chief of Infectious Diseases at Kaiser Hospital in San Leandro, CA, have been comparing rates of hospitalizations for Acute Myocardial infarctions and other forms of coronary artery disease between a group of HIV infected individuals and a large comparison group of uninfected health plan members. In the early years of their study, they noted an increased risk of coronary disease among HIV infected individuals. However in a recently published report, researchers found that there was no longer an excess risk.
Kaiser Permanente is a large, not-for-profit health care provider based in California. For more than 20 years, researchers have been collecting information on their HIV infected members. By matching the HIV patients to other uninfected health plan members who were of comparable age, sex and race, these investigators have been comparing the rates of a number of medical problems between the groups. Their first report on an excess risk of coronary artery disease was published in 2002. The original observation of an excess risk for heart disease was attributed to higher rates of certain conventional risk factors among the HIV group such as smoking as well as exposure to protease inhibitor class drugs.
Medical Research: What was the findings of this study?
Dr. Klein: By comparing the relative rates over time in the most recent study interval, there was no longer an increased risk for a Myocardial infarction among the HIV group as compared to the uninfected group when matched by age, sex and presence.
Medical Research: To what do the authors ascribe this recent finding?
Dr. Klein: A number of factors may have contributed to the results including increased attention to conventional risk factor reduction with greater use of lipid lowering therapies and smoking cessation programs. Also, newer HIV medications may have less association with premature coronary artery disease. In keeping with national guidelines, Kaiser patients are initiating HIV treatment at higher CD4 cell counts and of those on therapy, more than 85 percent have undetectable viral loads. In an earlier report, these researchers observed that patients who maintained CD4 cell counts over 500 had no excess risk of an MI confirming the role of immunodeficiency in premature coronary artery disease among HIV individuals.
Medical Research: What are the main take away messages from this study?
Dr. Klein: For patients, knowing whether you are HIV positive is key to entering care and preserving your immune function. Also if you are a smoker, quitting is the best thing you can do for your own health in conjunction with regular exercise and a healthy diet. For providers, aggressive conventional risk factor reduction efforts are clearly warranted, coupled with early initiation of antiretroviral treatments to preserve immune function, can translate into reduced heart disease in your patients.
What are the limitations of this study?
Dr. Klein: The majority of our HIV positive members were men so more information about outcomes among HIV infected women is needed. Also, the findings of no increased risk for MIs was over a two year period and further long-term follow up is warranted to ensure that this finding is sustained.
Clin Infect Dis. first published online January 16, 2015 doi:10.1093/cid/civ014
Daniel B. Klein, Wendy A. Leyden, Lanfang Xu, Chun R. Chao, Michael A. Horberg, William J. Towner, Leo B. Hurley, Julia L. Marcus, Charles P. Quesenberry, Jr., and Michael J. Silverberg