The role of systemic inflammation in the formation and rupture of intracranial aneurysms in moyamoya disease: a retrospective cohort study.

Background: Intracranial aneurysms (IAs) and their rupture are serious complications in patients with Moyamoya disease (MMD). However, specific risk factors for IA formation and rupture in MMD remain underexplored.

Methods: We conducted a retrospective analysis of 450 MMD patients, evaluating the prevalence and characteristics of IAs. We analysed peripheral blood markers, including white blood cell count, neutrophil count, lymphocyte count, monocyte count, platelet count, and calculated SII-related biomarkers (SII, NLR, PLR, MLR, GLR).

Results: Among the 450 MMD patients, 57 (12.67%) had a total of 73 IAs. Unilateral MMD patients had a significantly higher risk of IAs and multiple IAs compared to bilateral MMD patients (OR 1.97, 95% CI [1.02 - 3.71],  = 0.042; OR 5.76, 95% CI [1.16 - 23.55],  = 0.032). Aspirin use was associated with a lower incidence of IAs (OR 0.34, 95% CI [0.17 - 0.70],  = 0.002). The SII, NLR, GLR, MLR, and PLR were significantly elevated in patients with IAs compared to those without. ROC analysis showed AUC values of 0.610 for SII ( = 0.007), 0.593 for PLR ( = 0.024), 0.659 for NLR ( < 0.001), 0.665 for GLR ( < 0.001), and 0.658 for MLR ( < 0.001). In patients with ruptured IAs, SII, NLR, GLR, and MLR levels were significantly higher than in those with unruptured IAs, with AUC values for predicting IA rupture of 0.720 for SII ( = 0.002), 0.745 for NLR ( < 0.001), 0.727 for GLR ( = 0.001), and 0.717 for MLR ( = 0.002).

Conclusions: This study highlights the significant role of systemic inflammation in the formation and rupture of IAs in MMD patients. Elevated levels of SII and its constituent markers (NLR, PLR, MLR and GLR) are associated with an increased risk of IA development and rupture. Aspirin could reduce the risk of IA formation and rupture in MMD patients without increasing cerebral haemorrhage risk.