Risk Factors Associated with Rupture of Multiple Intracranial Aneurysms

Objective: To identify risk factors associated with multiple intracranial aneurysm (MIA) rupture. Methods: This retrospective study included patients with MIAs diagnosed at the center between February 2010 and December 2015. Patients were grouped based on their history of aneurysmal subarachnoid hemorrhage (aSAH) into ruptured and unruptured categories. In the ruptured group, aneurysms were further classified as ruptured MIAs (R-MIAs) and unruptured MIAs (U-MIAs). Patient- and aneurysm-related factors were analyzed using univariate analysis to determine their significance in rupture risk. Receiver operating characteristic (ROC) analysis was employed to calculate the area under the curve (AUC) and identify optimal thresholds for five morphological parameters distinguishing R-MIAs from U-MIAs. Results: Of 368 enrolled patients, 327 (86 with ruptured aneurysms and 241 unruptured) were included in the analysis. Among the ruptured group, 66 patients had R-MIAs and 96 had U-MIAs. Univariate analysis identified statistically significant factors associated with rupture, including BMI, irregular aneurysm shape, size, aspect ratio, size ratio, and bottleneck (P < 0.05). Size, size ratio, and bottleneck exhibited high AUC values (AUC > 0.7). ROC analysis determined an optimal threshold of 4.6 mm for MIA rupture size. Conclusions: Lower BMI, irregular aneurysm shape, larger size, larger size ratio, and bottleneck are associated with an increased risk of MIA rupture. Notably, MIAs may rupture at smaller sizes compared to single intracranial aneurysms.