Relationship between cerebrovascular atherosclerotic stenosis and rupture risk of unruptured intracranial aneurysm: A single-center retrospective study.

OBJECTIVES

Cerebrovascular atherosclerotic stenosis (CAS) and intracranial aneurysm (IA) have a common underlying arterial pathology and common risk factors, but the clinical significance of CAS in IA rupture (IAR) is unclear. This study aimed to investigate the effect of CAS on the risk of IAR.

PATIENTS AND

METHODS

A total of 336 patients with 507 sacular IAs admitted at our center were included. Univariable and multivariable logistic regression analyses were performed to determine the association between IAR and the angiographic variables for CAS. We also explored the differences in CAS in patients aged <65 and ≥65 years.

RESULTS

In all the patient groups, moderate (50%-70%) cerebrovascular stenosis was significantly associated with IAR (odds ratio [OR], 3.4; 95% confidence interval [CI], 1.8-6.5). Single cerebral artery stenosis was also significantly associated with IAR (OR, 2.3; 95% CI, 1.3-3.9), and intracranial stenosis may be a risk factor for IAR (OR, 1.8; 95% CI, 1.0-3.2). In addition, IAs with lobulation may be at a higher risk for rupture than IAs with regular shape (OR, 2.6; 95% CI, 1.1-5.8; P = 0.026), although the same was not true of aneurysms with a daughter sac (OR, 1.8; 95% CI, 0.9-3.7; P = 0.098). Bifurcation location (OR, 2.4; 95% CI, 1.5-3.8; P < 0.001) was significantly associated with aneurysmal rupture. For the patient subgroup aged <65 years, rupture risk was higher for aneurysms with moderate stenosis (OR, 3.4; 95% CI, 1.8-6.5). For patients aged ≥65 years, single-artery stenosis (OR, 1.9; 95% CI, 1.2-3.0) was statistically associated with IAR.

CONCLUSIONS

We observed substantial differences in the severity of atherosclerotic stenosis, parent-artery stenosis, number of stenotic arteries, and intracranial/extracranial stenosis as indicators between ruptured and unruptured aneurysms. CAS is significantly associated with the risk of intracranial aneurysm rupture, whether in patients aged ≥65 years or <65 years. These findings indicate the clinical significance of CAS in IAR.