Relationship between alpha-1-antitrypsin deficiency and ascending aortic distention

Abstract

Introduction: Alpha-1-antitrypsin deficiency (AATD), better known for its lung and liver disease manifestations, has also been linked to aneurysmal disease arising from increased elastin breakdown. Aim: To investigate the relationship between AATD and ascending aortic distention. Methods: This was a retrospective cohort study performed at a tertiary academic centre. Patients with computed tomography (CT) scans and panlobular emphysema due to AATD (AATD group) or non-AATD-associated emphysema (control group) were identified and patient demographics, including age and sex, were recorded. The diameter of the mid ascending aorta was measured from outer wall to outer wall using non-gated axial CT scans, with or without contrast. Mean diameter for each group was calculated and compared using a two-sample t-test. Pearson’s correlation coefficient was used to determine the relationship between ascending aortic diameter and age. Results: Patients with AATD (n=51) were approximately 10 years younger than those in the control group (n=96; mean age: 55±9.5 vs 65±7.2 years, respectively). There was no difference in mean aortic diameter (3.34±0.43 vs 3.37±0.39 cm; p=0.68), and no within gender difference in diameter (males: 3.49±0.45 vs 3.5±0.39 cm, p=0.9; females: 3.14±0.32 vs 3.18±0.31 cm, p=0.68) between the AATD and control groups, respectively. Aortic diameter significantly increased with age in the AATD group (r=0.43, p=0.0016); a relationship that was not seen in the control group (r=0.16; p=0.11). Conclusions: To the best of our knowledge, this is the first controlled study to assess the relationship between AATD and ascending aortic diameter, and suggests AATD is associated with accelerated aortic wall degeneration.