Risk factors of rupture and mortality for intracranial aneurysms associated with moyamoya disease: a multicenter retrospective study

The aim of this study was to analyze the risk factors for aSAH and subsequent death in patients with MMD.

Chinese Multi-Center Cerebral Aneurysm Database (CMAD) is a multicenter study registered in China. From 2016 to 2021, 181 patients with MMD in CMAD. Logistic regression analysis was used to identify risk factors for intracranial aneurysm rupture. Univariate and multivariate Cox regression were used to risk factors associated with ruptured intracranial aneurysm patients with MMD follow-up events (death). Cumulative survival was described using the Kaplan‒Meier technique.

Of 11,686 IA patients, 181 (1.5%) had MMD. In the study, 158 patients with MMD were enrolled. There were 53 ruptured aneurysms and 105 unruptured aneurysms. In multivariate analysis, age (≥ 60 years OR 2.350 [1.008–5.478]), location (middle cerebral artery OR5.431 [1.347–21.889]; posterior circulation arteries OR 3.189 [1.110–9.163]) and aneurysm size (≥ 5 mm OR 2.855 [1.274–6.397], P = 0.011) were associated with intracranial aneurysm rupture in patients with MMD. In the 2-year follow-up time of aSAH patients, 44% (22/50) had favorable outcomes, 14% (7/50) had unfavorable outcomes and 42% (21/50) had death. Hypertension (HR 6.643 [1.620–27.244], P = 0.009) and Hunt-Hess grade (H&H grade IV HR 14.852 [3.151–70.011], P = 0.001; H&H grade V HR 17.697 [3.046–102.842], P = 0.001) were associated with increased mortality. In contrast, both ST (HR 0.168 [0.031–0.921], P = 0.04) and ET (HR 0.289 [0.087–0.957], P = 0.042) achieved good results.

This study showed that the proportion of MMD in IA patients was approximately 1.5% (181/11686). For patients with cerebral ischemia on admission, revascularization may prevent the rupture of intracranial aneurysms. Age ≥ 60 years, location, and aneurysm size ≥ 5 mm were associated with IA rupture. Further analysis showed that being located in the middle cerebral artery was the most relevant risk factor for rupture. Patients with ruptured IA who underwent ST or ET had better clinical outcomes and survival than those who underwent CT; however, hypertension and poor initial Hunt-Hess grade were independent predictors of death.