Abstract 119: Risk of Intracerebral Hemorrhage with Combined Antiplatelet and Anticoagulant Use
Context: Intracranial bleeding is the most feared complication of antithrombotic use. Antiplatelet and anticoagulant drugs increase risk of intracerebral hemorrhage (ICH), yet in some instances, combinations of antiplatelet agents and anticoagulants are used without firm evidence of efficacy. Few studies have compared the risks of different agents and their combinations in a single population. We determined the risk of ICH associated with the most commonly used antiplatelet and anticoagulant drugs and their combinations in a population-based case-control study.
Methods: This report includes data from subjects recruited from the Greater Cincinnati/Northern Kentucky area by the Genetic and Environmental Risk Factors for Hemorrhagic Stroke Study from 1997 to 2009. We compared individuals in different treatment groups to identify any differences in baseline covariates that could be associated with treatment assignment. As there were a number of statistically significant differences, we used multivariate matching to analyze risk for ICH conferred by different antithrombotic agents. Treatment effects on ICH were estimated using the matched samples while accounting for the dependence between matched individuals.
Results: There were 733 subjects with ICH and 2555 controls included in this study period. Results are shown in the table. Use of aspirin, clopidogrel, or their combination was associated with a trend toward increased risk. Warfarin increased risk compared with no antithrombotic use (OR 3.98, p < 0.0001). The combination of warfarin and either aspirin or clopidogrel produced the greatest risk, compared with no antithrombic therapy (OR 4.92 p<0.001) or compared with warfarin alone (OR 3.00 p=0.009).
Conclusions: The combination of warfarin and an antiplatelet drug significantly increases risk of ICH compared with no antithrombotic therapy or warfarin monotherapy. The use of combination therapy requires careful consideration in clinical practice.
- © 2012 by American Heart Association, Inc.