A question came up recently on rounds regarding restarting plavix and aspirin for a patient with significant ischemic heart disease admitted to our service for subdural hematoma secondary to a fall down the stairs. Since this is a topic that comes up frequently for elderly patients with traumatic brain injury, I thought it would be interesting to discuss further.
After reviewing the literature, I could find no randomized controlled trials to date addressing the topic. This is most likely due to the ethical dilemma of prescribing a medication to which a patient has an apparent contraindication.
The studies I found were mostly retrospective, non-randomized studies of patients with primary intracranial hemorrhage, which does not include traumatic causes. Therefore, it will be difficult to extrapolate the findings to fit our population.
In one retrospective cohort study by Classen et al1, 20% of the patients in the non-reinitiated group who were mostly previously anitcoagulated for atrial fibrillation had a subsequent thromboembolic event. One of these events was fatal. In contrast, only one of 23 patients who were restarted on coumadin after ICH (mainly patients with history of valve replacement) subsequently sustained a recurrent non-traumatic bleed. This study (although not statistically significant) suggests that recurrent ICH is relatively uncommon after re-initiating coumadin as compared to the relatively high risk of thromboembolism in patients who are not restarted on coumadin. Of note, coumadin was restarted within 2 months after ICH.
Another retrospective cohort study by Vidal-Jordana et al2., also with a small sample size, describes a 24% rate of recurrent ICH in the patients restarted on coumadin vs 7% in the comparison group that was switched to antiplatelet therapy. Risk of ischemic CVA was higher in the antiplatelet group (14%) vs 8% in the coumadin group. The study did not specify when coumadin or aspirin was restarted. This study suggests a significant risk of rebleed after reinitiating coumadin.
The conclusion that can be drawn from limited, somewhat contradictory studies is that restarting anticoagulation should be determined on an individual basis depending on the location of ICH, cardiovascular risk factors and the indication for anticoagulation.
When specifically looking at the risk of restarting antiplatelets after ICH, Viswanathan et al.3 used data from a prospective cohort study to conclude that antiplatelets did not significantly increase risk of recurrent ICH. Of note, the median time of initiation of antiplatelet agent was 5.4 months after the index ICH.
Another cohort study by Flynn et al.4 also examined the risk of antiplatelets after ICH and similarly concluded no difference in rates of recurrent ICH in the study vs control groups.
The current AHA recommendations are to consider an antiplatelet agent for patients with comparatively lower risk of cerebral infarction (AF without prior ischemic stroke) and higher risk of amyloid angiopathy (elderly patients with lobar ICH) or with very poor overall neurological function. Restarting coumadin can be considered in patients with very high risk of thromboembolism (prosthetic valves, dilated cardiomyopathy, documented intracardiac thrombus). It may be reasonable to restart coumadin within 7-10 days after onset of orignial ICH (Class IIb, Level of Evidence B).
REFERENCES
1. Classen, DO, et al. Restarting Anticoagulation Therapy After Warfarin-Associated Intracerebral Hemorrhage. Arch Neurol 2008. 65(10): 1313-1318.
2. Vidal-Jordana A, et al. Intracerebral hemorrhage in anticoagulated patients: What do we do afterwards? Neurologia, 2012. 27:136-42.
3. Viswanathan A, et al. Antiplatelet use After Intracerebral hemorrhage. Neurology, 2006. 66:206-209.
4.Flynn R, et al. Prescribing Antiplatelet Medicine and Subsequent Events after Intracerebral Hemorrhage. Stroke, 2010. 41:2606-2611.
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