Introduction: Plasma lipoprotein-associated phospholipase A2 (Lp-PLA2) generates bioactive lipids eliciting vascular inflammation and is used as a marker for cardiovascular and atherothrombotic disease. High sensitivity C-reactive protein (hs-CRP) has shown correlation with cardiac and cerebral ischemic events. We examine the utility of serum Lp-PLA2 and hs-CRP to assess cerebral aneurysms at higher rupture risk.

Methods: Between June 2009 to July 2010 serum levels of Lp-PLA2 and hs-CRP were measured in patients with ruptured (Group A) and unruptured (Group B) aneurysms along with healthy controls (Group C). Patient characteristics and serum marker levels within each group underwent analysis.

Results: 33 patients with ruptured and 23 patients with unruptured aneurysms and 9 healthy volunteers were enrolled. Using the ANOVA test, the mean level of Lp-PLA2 in Group A was 192 (SD ± 79), Group B 195 (SD ± 83), Group C 159 (SD ± 104) ng/ml. hs-CRP values in each group were 23 (SD ± 32), 6 (SD ±10) and 1.4 (SD ± 1.4) mg/l, respectively. No statistically significant difference (p = 0.49) was found in Lp-PLA2 values between groups A and B but hs-CRP was significantly higher in Group A (p = 0.009).

Conclusions: We found no significant difference in Lp-PLA2 levels between patients with ruptured versus unruptured aneurysms. After aneurysmal subarachnoid hemorrhage higher hs-CRP levels are seen but may not be specific for vascular inflammation. Lp-PLA2 and hs-CRP cannot be used to identify aneurysms at risk for rupture but a larger cohort is needed to elucidate this potentially predictive biomarker.

Patient Care: The use of biomarkers to predict cerebral aneurysms at highest risk for rupture will help guide decision making for the operative and/or interventional management of nonruptured cerebral aneurysms. Our research looks to elucidate the validity using commercially available serum assays for commonly measured biological substrates.

Learning Objectives: - Potential biomarkers of cerebral aneurysm rupture - Inflammatory milieu of cerebral aneurysms - Predictors of aneurysm rupture

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