Aspirin Holds Potential for Stroke Prevention in Cerebral Amyloid Angiopathy

Sheharyar Jamali, MD

Research conducted by Sheharyar Jamali, MD, and Michelle Lin, MD, MPH, showed that aspirin lowers the risk of ischemic stroke without increasing the risk of intracranial hemorrhage in patients with cerebral amyloid angiopathy. The findings, presented at the 2021 American Academy of Neurology (AAN) Annual Meeting, April 17-22, further characterize the risks and benefits of antiplatelet agents for stroke prevention in this patient population.

Among the 38 patients included in the cohort, 39% were treated with aspirin 81 mg to 325 mg daily at a single academic center from 2011 to 2018 and were followed until 2020 for incident ischemic stroke and intracranial hemorrhage occurrence. Due to the relatively small number of patients included in the cohort, the study did not achieve statistical significance.

Jamali, a neurologist from Mayo Clinic, noted that despite the insignificance, these results open the door for future research opportunities to evaluate the use of antiplatelets among patients with cerebral amyloid angiopathy and other similar diseases. As part of our ongoing coverage of AAN 2021, he sat down to discuss his study in detail and how aspirin can be utilized more effectively going forward.

NeurologyLive: What motivated you to conduct this study, and were you surprised by any of the outcomes?

Sheharyar Jamali, MD: What motivated me to do this project was seeing patients in the hospital with cerebral amyloid antipathy who presented with ischemic stroke. In research, and from what we know best, is that this disorder increases your risk of bleeding in the brain or intracranial hemorrhage. It is not as well known, but definitely reported in the literature there is also a risk of ischemic stroke in these patients. In fact, 15% to 24% of these patients will have an ischemic stroke in their lifetime because of the vasculopathy alone. That’s what motivated me to do this project.

I wanted to study ways that we can prevent ischemic stroke in these patients without also increasing the risk of bleeding. We looked at aspirin versus no aspirin in these patients. We followed 38 patients over about an average of 32 months and recorded the incidence of ischemic stroke and intracranial hemorrhage. We found that in patients who were taking aspirin, the risk of ischemic hemorrhage was lower. Additionally, the risk of intracranial hemorrhage was not higher in patients taking aspirin, which was a little bit unexpected, but that’s why we decided to conduct the research.

What is the current state of research for cerebral amyloid antipathy? Is this an area that requires more attention?

Cerebral amyloid angiopathy is a disorder that affects the small blood vessels in the brain and causes them to be very leaky, thus increasing the risk of intracranial hemorrhage. This risk increases by 9% per year in these patients, which is well known in the literature. Again, there is also a risk of ischemic stroke in these patients, which needs more attention. Patients with cerebral amyloid angiopathy tend to be older. In these patients, there are also comorbidities such as high blood pressure, diabetes, and high cholesterol that causes atherosclerotic diseases over time and increase the risk of ischemic stroke that presents a therapeutic challenge. Can we use blood thinning medications to reduce the risk of ischemic stroke safely without also increasing the risk of intracranial hemorrhage?

Despite not achieving statistical significance, what do you hope these study results accomplish?

In our study we followed a small group of patients and we did not find any statistical significance in any of our results, meaning that there aren’t any direct conclusions that we can draw from this study alone. I think this study does serve to raise some attention as to the questions at hand. How do we prevent the ischemic stroke burden in these patients with cerebral amyloid angiopathy? In the future, more studies are needed that follow large patient cohorts to draw more statistically significant conclusions. The best study we can do is a randomized controlled trial, where we randomize patients with cerebral amyloid angiopathy into an aspirin versus no aspirin arm and see whether there’s an increased risk of ischemic or hemorrhagic stroke in that scenario.

What other areas or diseases might these findings be applied to?

Absolutely. I think an interesting topic to study in the future would be to look at patients with cerebral amyloid angiopathy who also have another disorder called atrial fibrillation. Atrial fibrillation an arrhythmia that can increase risk of stroke. Patients with atrial fibrillation oftentimes are treated with blood thinning agents. Both of these disorders, by the way, increases in prevalence with age. We oftentimes come into this conundrum where we have a patient with atrial fibrillation but putting them on a blood thinning agent will increase the risk of intracranial hemorrhage. I would like to study or see other studies that look at antiplatelet use to prevent ischemic stroke in patients with both cerebral amyloid angiopathy and atrial fibrillation.

Transcript edited for clarity. For more coverage of AAN 2021, click here.

REFERENCE

Jamali S, Lin M. Incident ischemic stroke and intracranial hemorrhage in patients with cerebral amyloid angiopathy on aspirin versus none. Presented at 2021 American Academy of Neurology Annual Meeting; April 17-22. Abstract P5 219