Serum lipoprotein-associated phospholipase A2 predicts the formation of carotid artery plaque and its vulnerability in anterior circulation cerebral infarction

Objective: Circulation inflammation markers such as high-sensitive C-reactive protein (hsCRP) and lipoprotein-associated phospholipase A2 (Lp-PLA2) are considered as predictors of cerebral and cardiac vascular diseases. However, the role of hsCRP and Lp-PLA2 in the anterior circulation cerebral infarction (ACI) is to be elaborated.

Patients and methods: We included 100 patients with acute anterior circulation cerebral infarction (AaCI group) and 50 non-infarction subjects (control group). Carotid artery was detected by color Doppler ultrasound. Subjects were grouped based on carotid intima-media thickness (IMT) and degree of stability of carotid atherosclerotic plaque. The levels of hsCRP and Lp-PLA2 were measured in corresponding groups and the association was analyzed.

Results: hsCRP and Lp-PLA2 levels were the risk factors for AaCI. With the increment of carotid IMT and degree of plaque instability, the level of hsCRP and Lp-PLA2 showed an elevating tendency. hsCRP and Lp-PLA2 levels were significantly higher in plaque formation group than in IMT normal group (P=0.002 and P=0.001, respectively). hsCRP and Lp-PLA2 levels were significantly higher in vulnerable plaque group than in mixed plaque group and stable plaque group (P=0.003, P<0.001 for hsCRP and P<0.001, P<0.001 for Lp-PLA2). Lp-PLA2 was finally included in the atherosclerotic plaque model (OR=1.019, 95% confidence interval (CI): 1.003-1.035, P=0.020) and vulnerable plaque model (OR=1.041, 95%CI: 1.017-1.065, P=0.001) by performing multivariate logistic regression analysis. The area under the ROC curve (AUC) of Lp-PLA2 levels for atherosclerotic plaque was 0.746 (95% CI: 0.628-0.865, P<0.001). The optimal cut-off value for Lp-PLA2 level was 267.5ng/ml, and its sensitivity and specificity for diagnosis of atherosclerotic plaque were 70.8% and 67.1%, respectively.

Conclusions: The current study demonstrates that hsCRP and Lp-PLA2 are among the risk factors for AaCI. Elevated hsCRP and Lp-PLA2 are associated with carotid plaque formation. Univariate and multivariate logistic regression analysis suggests that elevated Lp-PLA2 is the independent risk factor for carotid plaque and its vulnerability.