Adults who develop dissecting aneurysms following cervical artery dissection do not have an increased risk of stroke during the first six months after diagnosis compared to those with cervical artery dissection alone, according to preliminary research to be presented at the American Stroke Association's International Stroke Conference 2026. The findings, based on analysis of global registry data, provide important clinical guidance for managing this condition that disproportionately affects younger adults.
Cervical artery dissection (CeAD), which involves a tear in the inner wall of a neck artery, causes approximately 2% of all ischemic strokes but accounts for up to 25% of strokes in adults under 50. When blood leaks through this tear, it can form a clot that may travel to the brain and cause a stroke. In some cases, the leaking blood creates a bulge in the artery called a dissecting aneurysm. "We have little scientific information about dissecting aneurysm, including how to best diagnose, monitor aneurysm growth and manage the health of people with dissecting aneurysms," said study author Muhib Khan, M.D., M.B.B.S., an associate professor in neurology at the Mayo Clinic in Rochester, Minnesota.
The research analyzed data from the Antithrombotics for Stroke Prevention in Cervical Artery Dissection (STOP-CAD) study, a multicenter international registry that enrolled 4,008 adults diagnosed with CeAD between 2010 and 2023 at 63 sites across 16 countries. Approximately 19% of participants (767 people) developed dissecting aneurysms. The analysis revealed that people with dissecting aneurysms were more likely to have a history of migraines, connective tissue disorders, and minor neck trauma before the dissection, factors that may help clinicians monitor for aneurysm development.
Most significantly, the study found no increased stroke risk among those with dissecting aneurysms compared to those without. Among participants with dissecting aneurysms, about 10% showed aneurysm growth over six months, but this growth also did not lead to higher stroke risk. "Reassuringly, dissecting aneurysm formation was not related to hemorrhagic stroke or increased mortality either," said study co-author Zafer Keser, M.D., also an associate professor in neurology at the Mayo Clinic.
The findings could change clinical practice by reducing unnecessary medical interventions. "Often, we follow these patients with a lot of imaging that we may not need to do quite as often," said Louise D. McCullough, M.D., Ph.D., FAHA, former chair of the International Stroke Conference. "These results will probably give us a little bit of pause if we're thinking about doing an intervention such as placing a carotid stent - which would require chronic antiplatelets - if we know the risk of recurrent strokes in patients with dissecting aneurysms is low."
Researchers noted limitations including the retrospective design and lack of standardized assessment processes. They emphasized that the findings are preliminary until published in a peer-reviewed journal. The study abstract is available in the American Stroke Association International Stroke Conference 2026 Online Program Planner. Additional information about stroke can be found at www.stroke.org or through the American Heart Association's Stroke Hub.
