Link between lipoprotein-associated phospholipase A₂ gene expression of peripheral-blood mononuclear cells and prognostic outcome after acute ischemic stroke

Aim: To evaluate the potential of the lipoprotein-associated phospholipase A₂ (Lp-PLA₂) level as a biomarker in the prediction of prognostic outcome in patients with acute ischemic stroke (IS). Methods: From October 2008 to March 2010, 130 patients with acute IS were prospectively enrolled in the study and their medical records were reviewed. A blood sample was collected from each patient 48 hours after acute IS, as well as from 20 healthy volunteers as controls. Messenger-RNA (mRNA) expression of Lp-PLA₂ of peripheral-blood mononuclear cells (PBMNCs) relative to that of β actin was measured using quantitative reverse transcription polymerase chain reaction (RT-PCR). Results: Patients with acute IS exhibited significantly higher Lp-PLA₂ mRNA expression of PBMNCs than the control group (p=0.0001). Lp-PLA₂ mRNA expression of PBMNCs in patients with a major adverse clinical outcome (MACO) (defined as recurrent stroke or death) within 90 days was significantly higher than in patients without MACO (p=0.006). Furthermore, elevated Lp-PLA₂ mRNA expression was strongly associated with old age, diabetes mellitus, a positive history of significant coronary arterial disease and significant stenosis of the extra-cranial carotid arteries (all p=0.04), and positively correlated with the body mass index, leukocyte count, and serum levels of total cholesterol and low-density lipoprotein cholesterol. Multivariate analysis revealed that Lp-PLA₂ mRNA expression of PBMNCs was a significant independent predictor of MACO within 90 days (p=0.011). Conclusion: Elevated Lp-PLA₂ mRNA expression of PBMNCs seems to be a potential biomarker for predicting an unfavorable outcome in patients with acute IS.