Abstract
RATIONALE AND OBJECTIVES: Inflammation and lipid metabolism play critical roles in the pathophysiology of intracranial aneurysm instability. However, their comprehensive relationships across different features of aneurysm progression, including aneurysm wall enhancement and growth remain unclear. This study aimed to investigate their associations with aneurysm instability.</p>
MATERIALS AND METHODS: This study included three datasets. The cross-sectional cohort, comprising 308 patients with 416 intracranial aneurysms (IAs), and the longitudinal cohort, comprising 80 patients with 85 IAs, were both recruited at our hospital between May 2022 and November 2024. The cross-sectional cohort was used to evaluate the associations of the neutrophil-to-HDL cholesterol ratio (NHR) and the systemic inflammation response index (SIRI) with aneurysm wall enhancement (AWE), and the longitudinal cohort was used to assess aneurysm growth. In addition, data from the UK Biobank were used to provide population-level support for these associations by examining the relationships of NHR and SIRI with incident aneurysmal subarachnoid hemorrhage (aSAH).</p>
RESULTS: In the cross-sectional cohort, higher NHR and SIRI were significantly associated with the presence of AWE, with ORs of 1.23 (95% CI, 1.07-1.41) and 1.31 (95% CI, 1.01-1.70), respectively. Ordinal regression further confirmed their associations with AWE severity, with ORs of 1.17 (95% CI, 1.04-1.32) and 1.28 (95% CI, 1.01-1.63), respectively. In the longitudinal cohort, both indices were associated with aneurysm growth, with ORs of 1.42 (95% CI, 1.04-2.10) and 2.65 (95% CI, 1.31-5.33), respectively. In the UKB cohort, higher NHR was associated with incident aSAH (HR = 1.05, 95% CI: 1.03-1.07). No statistically significant association was observed between SIRI and aSAH.</p>
CONCLUSION: Elevated NHR and SIRI levels were associated with AWE, and their relationship with aneurysm growth was explored. These findings suggest that they may serve as noninvasive hematologic indicators reflecting intracranial aneurysm instability, although further validation is required.</p>