Multivariable analysis on factors associated with aneurysm rupture in patients with multiple intracranial aneurysms

Multiple intracranial aneurysms (MIA) occur in one-third of patients with intracranial aneurysms (IA), and have been previously associated with an overall worse prognosis. Risk factors for IA formation and rupture in patients with a single IA are well-known. However, risk factors associated with rupture in patients with MIA have been less studied.

We performed a retrospective search of patients with MIA identified by computed tomography angiography (CTA) within a 10-year period. Patients with > 1 saccular aneurysm with size ≥ 2.0 mm were included. The location, size, number, and rupture status of the aneurysms were recorded. Patient demographics and cerebrovascular risk factors were obtained from electronic medical records. The primary endpoint of this study was to determine the association of these factors with aneurysmal rupture. The case-fatality rate was evaluated as a secondary outcome.

Of the 2957 patients with IA in our CTA database, 425 patients were diagnosed with MIA and were therefore included in our study. A total of 1082 aneurysms were identified. Predictors of increased risk of aneurysmal rupture were age (OR 0.98, 95% CI, 0.96-0.99), size ≥ 5 mm (OR 4.4, 95% CI 2.76-7.0); and location in the anterior communicating artery complex (AcomC) (OR 2.62, 95% CI, 1.46-4.72) or posterior communicating artery (PCOM) (OR 2.66, 95% CI, 1.45-4.87).

Younger age, aneurysm size ≥ 5 mm, and location in the AcomC and PCOM were independently associated with aneurysmal rupture in patients with MIA. Identifying these features could help recognize patients who might benefit from early intervention.