Protease inhibitors in spontaneous cervical artery dissections

Background and Purpose-Observations in patients with arterial aneurysms, fibromuscular dysplasia, and spontaneous cervical artery dissection (sCAD) indicate that protease inhibitor deficiency might boost the enzymatic destruction of arterial tissue and increase the risk of these arterial wall diseases. Here we present the first large investigation of the protease inhibitor hypothesis in patients with sCAD. Methods-Eighty patients with sCAD were compared with 80 age- and sex-matched healthy individuals. alpha(1)-antitrypsin (alpha(1)-AT) and alpha(2)-macroglobulin (alpha(2)-MG) levels, and alpha(1)-AT genotypes were assessed and compared between groups. Results-alpha(1)-AT and alpha(2)-MG levels as well as alpha(1)-AT genotypes did not differ significantly between patients and controls. The frequency of Z alleles in the patient group was higher than in the control group and than in other cohorts from Europe; however, the difference remained nonsignificant. All patients with Z alleles had internal carotid artery dissections. Conclusions-Overall, this data does not support the hypothesis that protease inhibitor levels or alpha(1)-AT genotypes play an important role in the etiology of sCAD. The present data does not exclude that the Pi-Z allele might have an influence on subgroups of sCAD, such as internal carotid artery dissections.