Systemic Inflammation Response Index May Be Associated with Aneurysmal Wall Enhancement and Overall Poor Outcomes in...

Inflammation plays a crucial role in the pathophysiology of intracranial aneurysms (IAs). Our previous research demonstrated that blood inflammatory indices can serve as predictors of aneurysmal wall enhancement (AWE), which signifies the presence of inflammation within the aneurysmal wall and functions as an imaging biomarker for IA instability. Here, we aimed to further examine the relationship between blood inflammatory indices, AWE, and long-term clinical outcomes in patients with intracranial fusiform aneurysms (IFAs).

We reviewed patients with IFAs who underwent high-resolution magnetic resonance imaging and blood laboratory tests, as recorded in our maintained database. Initially, a cross-sectional study was conducted to identify potential blood inflammatory indices that could predict the average value of aneurysmal wall enhancement in three dimensions (3D-AWE_avg). Subsequently, a follow-up study was performed to further elucidate the potential predictors associated with overall poor outcomes (CAO) in the same cohort.

A total of 92 patients were included in the cross-sectional study. Both the systemic inflammation response index (SIRI), the systemic immune-inflammation index (SII), and the neutrophil-to-lymphocyte ratio (NLR) were associated with 3D-AWE_avg in univariate analysis; however, only SIRI was found to independently predict 3D-AWE_avg (P = 1.1 × 10^-5). In the follow-up study, 64 patients were included, with a mean follow-up period of 29.27 months. SIRI (13.725 [2.467-76.349], P = .003) and 3D-AWE_avg (5.387 [1.320-21.988], P = .019) were identified as the predictors of CAO in patients with IFAs. Furthermore, patients with a high SIRI value (≥0.725 × 10⁹/L, log-rank = 0.002) or a 3D-AWE_avg ≥ 0.604 (log-rank = 3 × 10^-5) had significantly higher risk of CAO.

SIRI predicts both aneurysmal wall enhancement and long-term adverse outcomes in patients with IFAs, supporting its potential role as a novel biomarker for risk stratification and clinical decision-making in this population.