NEW YORK (Reuters Health) – Anemia increases the risk of bleeding and death after percutaneous coronary intervention (PCI) for ST-segment elevation myocardial infarction (STEMI), a new study shows.

Furthermore, the impact of anemia on mortality is greater in men, according to the April 5th online report in the American Journal of Cardiology.

Lead author Dr. Gregg W. Stone of Columbia University Medical Center, New York, and colleagues conducted a post hoc analysis of data on 3153 participants in the HORIZONS-AMI trial who had primary PCI for STEMI. The analysis focused on the effect of anemia on outcomes.

The point of the original trial was to compare bivalirudin alone with unfractionated heparin plus a glycoprotein IIb/IIIa inhibitor, given before the procedure. At baseline, 10.5% of patients had anemia.

Bivalirudin lowered rates of all-cause and cardiac mortality and major bleeding by twice as much as heparin plus the glycoprotein IIb/IIIa inhibitor – but only in patients without anemia. In anemic patients, bivalirudin had “no such benefit,” the researchers say.

Anemic patients were more than twice as likely to have major bleeding within 30 days (13.5% vs 6.7%; p < 0.0001) and within 1 year (14.8% vs 7.2%; p < 0.0001). On multivariate analysis, this association was independent of gender.

But gender did affect the risk of death in anemic patients. Men with anemia had significantly higher mortality rates at 30 days (4.6%, vs 1.8% in men who were not anemic; p < 0.003) and at 1 year (8.9% vs 3.0%; p < 0.0001). But for women with and without anemia, respectively, there was no significant increase in risk, with mortality rates of 5.3% vs 3.6% at 30 days and 7.5% vs 5.9% at 1 year.

On multivariate analysis, anemia independently predicted 1-year all-cause mortality in men but not in women.

Patients with anemia also had higher 30-day stroke rates, but anemia was not linked with risks for reinfarction, stent thrombosis, or target vessel revascularization.

In email to Reuters Health, Dr. Stone commented that “patients who are anemic are also more likely to develop bleeding complications from the drugs and procedures that are used to treat a heart attack.”

“It is therefore imperative in the general population to treat anemia, and in patients with heart attack to use procedures and drugs that prevent bleeding for the best chance for survival,” he added.

Reference:
Am J Cardiol 2010.