Daniel M. Keller, PhD

October 04, 2012

October 4, 2012 (San Francisco, California) — Patients infected with HIV who receive care for acute myocardial infarction (AMI) have a 64% greater risk for in-hospital death than those not infected. HIV-infected patients also undergo fewer cardiovascular procedures.

These findings were reported here at the 52nd Interscience Conference on Antimicrobial Agents and Chemotherapy by Daniel Pearce, DO, associate clinical professor at Loma Linda University in California.

Dr. Pearce and colleagues analyzed data from the Nationwide Inpatient Sample (NIS) from 1997 to 2006 to compare outcomes in patients seropositive and seronegative for HIV.

The NIS represents about 20% of all hospitalizations in the United States. The researchers identified patients who experienced an AMI — approximately 600,000 with HIV and approximately 2.5 million without HIV. Only patients who were admitted to the hospital and survived at least 1 day were included in the analysis.

This study is "a huge database study, but database studies have their limitations," Dr. Pearce cautioned.

After adjustment for age, sex, and ethnicity, AMI patients who were seropositive for HIV had a 1.64-fold (95% confidence interval [CI], 1.20 to 2.25; P < .02) greater risk of dying than AMI patients who were seronegative for HIV.

After adjustment for medical comorbidities and hospital type (rural, urban, teaching, nonteaching), the risk remained elevated (hazard ratio [HR], 1.41), as it did after adjustment medical comorbidities, hospital type, and number of in-hospital procedures (HR, 1.38). Although not statistically significant, the data suggest that the increased risk applies to both non-ST-elevation and to ST-elevation myocardial infarctions.

Overall, 4% of seropositive patients and 2% of seronegative patients died, Dr. Pearce said.

There was less hypercholesterolemia in the seropositive patients than in the seronegative patients. The seropositive patients also tended to be younger and to smoke less. However, seropositive patients received fewer antiplatelet agents and less anticoagulation treatment than seronegative patients. "The HIV patients had fewer procedures done, including cardiac catheterization, percutaneous transluminal coronary angioplasty, and angiograms," Dr. Pearce noted.

Seropositive patients received fewer thrombolytics/anticoagulants than seronegative patients (17.6% vs 22.2%), and underwent fewer coronary arteriograms (48.0% vs 62.5%), fewer left cardiac catheterizations (52.2% vs 66.0%), and fewer coronary artery bypass grafts (6.0% vs 13.8%).

Intimal and endothelial problems from inflammation associated with HIV might have led to the more severe cardiovascular outcomes in the seropositive patients, Dr. Pearce explained.

These findings are in contrast to those from a much smaller retrospective review of the medical records of hospitalized patients, which was also presented here. In that study, although unstable angina and myocardial infarction were more common in seropositive than in seronegative patients undergoing coronary artery catheterization, "patients were managed in an exactly equivalent way," regardless of HIV status.

Jean-Michel Molina, MD, PhD, from Saint-Louis Hospital and the University of Paris, France, told Medscape Medical News that the study by Dr. Pearce and colleagues raises the issue of risk for myocardial infarction in patients infected with HIV.

"In a number of studies, we see more and more comorbidities, in particular cardiovascular disease and myocardial infarction," Dr. Molina said. "It's clear that we have to be aware of these risks in these patients even though they might be younger than noninfected patients," he added.

He explained that it is difficult to compare seropositive and seronegative patients "because there are a number of confounding variables [related to cardiovascular risk] that you can not adjust for in this type of analysis."

Dr. Molina noted that end points other than the usual outcomes, such as opportunistic infections, cardiovascular events, and cancer, are now being incorporated into HIV trials.

There was no commercial funding for this study. Dr. Pearce and Dr. Molina have disclosed no relevant financial relationships.

52nd Interscience Conference on Antimicrobial Agents and Chemotherapy (ICAAC): Abstract H-228. Presented September 9, 2012.