Total and differential leukocyte counts in ischemic stroke caused by vertebrobasilar artery dissection

Introduction: Vertebrobasilar artery dissection(VBD) is a common etiology of posterior circulation stroke(PCS). However, the etiology of VBD itself remains unclear. The present study aimed to test whether inflammation is involved in the mechanism of VBD by evaluating its relationship with total and differential leukocyte counts. Methods: Patients with PCS caused by VBD or by large artery atherosclerosis(LAA) were recruited between January 1, 2012 and December 31, 2014 from the Taipei Veterans General Hospital. Age- and sex-matched non-stroke(NS) volunteers were also included. Univariate and multivariate analyses were performed to compare total/differential leukocyte counts among VBD, LAA, and NS groups. Results: One-hundred-one patients with VBD [average age: 64.8(15.1) years; 77(76.2%) males], 70 with LAA [average age: 73.9(10.6) years; 44(62.9%) males], and 202 NS [average age: 64.8(15.1) years; 77(76.2%) males] patients were included in the present study. Compared with the NS and LAA groups, respectively, the VBD group had significantly higher total leukocyte and neutrophil counts and frequency of high leukocyte (> 10,000 x 10(6)/L) and high neutrophil (> 8000 x 10(6)/L) counts. Multivariate analyses, adjusted for age, sex, and vascular risk factors, showed that the VBD group, compared with the other groups, had an odds-ratio of 5.04 (95% confidence interval:2.43-10.43) and 5.90 (2.70-12.92) with respect to the prevalence of high leukocyte and high neutrophil counts. Conclusion: VBD was associated with high leukocyte and neutrophil counts. Our results support that inflammation and neutrophil-related pathophysiology might be involved in the mechanism of VBD; however, the causal relationship would need further investigations.