Italian researchers discovered that alpha-1 antitrypsin deficiency (AATD) could potentially be a risk factor for the development of abdominal aortic aneurysm (AAA), according to a study published in the Annals of Vascular Surgery.

Alpha-1 antitrypsin (AAT) plays a crucial role in shielding vascular tissue from damage due to proteinases, earning it the title of “guardian of the vascular tissue” in 1994. In the last decade, an association between AAT and AAA has been proposed. The hypothesis is that the unopposed increase in neutrophil elastase in AATD progressively degrades the extracellular matrix (ECM) into the vascular wall, causing it to become more unstable and thus vulnerable to rupture. In addition, local and systemic inflammation promoted by AATD may contribute to the development of AAA. 

Researchers investigated the possibility of this association by analyzing data from patients who were scheduled to receive AAA surgery in 1 year’s time. They recruited 138 patients with AAA at the Vascular Surgery Unit of the Spedali Civili in Brescia, Italy. Patients with AAA from traumatic causes and those with known collagen diseases such as Marfan’s syndrome were excluded from the study. 


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Of the 138 patients, 22 were found to have AATD. Patients had both AAT and C-reactive protein (CRP) measured to ensure that AAT values were not artificially higher due to systemic inflammation. The high-sensitivity immunoturbidimetric CRP (HS-CRP) method was used for CRP quantification. 

Further analysis showed that AAT levels were significantly lower in patients with AATD than in the non-AATD group (171.3 ± 63.29 mg/dL vs 209.5 ± 81.59 mg/dL; P <.05), and there was no statistically significant difference in HS-CRP values between the groups (2.4 ± 3.6 mg/L vs 1.8 ± 2.3 mg/L). The authors of the study explained, “Even if the HS-CRP values are below the lower limit related to a systemic inflammatory condition, the calculated mean value higher than 2 mg/L in the AATD group of patients is suggestive of an increased cardiovascular risk condition.”

AATD can therefore be considered a risk factor for the development of AAA. This is significant because the early diagnosis of AAA through the identification of risk factors can help physicians establish an appropriate follow-up regimen and plan for surgery if necessary.

Reference

Pini L, Peroni M, Zanotti C, et al. Investigating the link between alpha-1 antitrypsin deficiency and abdominal aortic aneurysms.  Ann Vasc Surg. Published online August 26, 2021. doi:10.1016/j.avsg.2021.05.064