Aspirin and Growth of Small Unruptured Intracranial Aneurysm
Jiancong Weng, Jie Wang, Hao Li, Yuming Jiao, Weilun Fu, Ran Huo, Zihan Yan, Hongyuan Xu, Jiong Zhan, Shuo Wang, Xin Du, Yong Cao, Ji-Zong Zhao, on behalf of the Small Unruptured Aneurysms Study Group
Abstract
Background and Purpose: The role of aspirin in unruptured intracranial aneurysm (UIA) growth remains largely unknown. We aim to identify whether aspirin is associated with a lower rate of UIA growth in patients with UIA <7 mm. Methods: This prospective cohort study consecutively enrolled patients with UIAs <7 mm with ischemic cerebrovascular disease between January 2016 and December 2019. Baseline and follow-up patient information, including the use of aspirin and blood pressure level, were recorded. Patients were considered aspirin users if they took aspirin, including standard- and low-dose aspirin, ≥3× per week. The primary end point was aneurysm growth in any direction or an indisputable change in aneurysm shape. Results: Among the 315 enrolled patients, 272 patients (86.3%) underwent imaging examinations during follow-up (mean follow-up time, 19.6±12.7 months). A total of 113 patients were continuously treated with aspirin. UIA growth occurred in 31 (11.4%) patients. In the multivariate Cox analysis, specific aneurysm locations (anterior communicating artery, posterior communicating artery, or middle cerebral artery; hazard ratio, 2.89 [95% CI, 1.22–6.88]; P =0.016) and a UIA size of 5 to <7 mm (hazard ratio, 7.61 [95% CI, 3.02–19.22]; P <0.001) were associated with a high risk of UIA growth, whereas aspirin and well-controlled blood pressure were associated with a low risk of UIA growth (hazard ratio, 0.29 [95% CI, 0.11–0.77]; P =0.013 and hazard ratio, 0.25 [95% CI, 0.10–0.66]; P =0.005, respectively). The cumulative annual growth rates were as high as 40.0 and 53.3 per 100 person-years in the high-risk patients (>1 risk factor) with and without aspirin, respectively. Conclusions: Aspirin therapy and well-controlled blood pressure are associated with a low risk of UIA growth; the incidence of UIA growth in high-risk patients in the first year is high, warranting intensive surveillance in this patient group. Registration: URL: https://www.clinicaltrials.gov . Unique identifier: NCT02846259.