Levels of α 1 -Antitrypsin in Plasma and Risk of Spontaneous Cervical Artery Dissections

Abstract

Background and Purpose— Abnormalities of dermal connective tissue have been detected in patients with spontaneous cervical artery dissections (sCAD), suggesting an underlying structural defect of the arterial wall. α 1 -Antitrypsin (A1-AT) is a circulating serine proteinase inhibitor of proteolytic enzymes that helps to maintain the integrity of elastic and collagen fibers. Methods— To test the hypothesis that moderate deficiency of A1-AT may be a risk factor for sCAD, 22 cases with sCAD and 113 controls were included in the study. Results— Patients with sCAD had significantly mean lower levels of A1-AT compared with controls (116.0±24.9 versus 141.1±31.7 mg/dL; P <0.01). Low levels of A1-AT (<90 mg/dL) were more frequently observed in patients with sCAD compared with controls (27.3% versus 2.7%; P <0.001). A positive correlation between age and plasma levels of A1-AT was found ( r =0.22; P <0.01). A1-AT levels were not affected by sex or vascular risk factors, including smoking habit. On multivariate analysis, A1-AT <90 mg/dL was associated with sCAD independently of age, sex, or vascular risk factors (odds ratio, 17.7; 95% confidence interval, 2.9 to 105.6). Conclusions— Low plasma levels of A1-AT may be a risk factor for sCAD.