Simple Renal Cysts Linked to Higher Abdominal Aortic Aneurysm Formation Risk

Compared with individuals without abdominal aortic aneurysms (AAA), patients with AAA have a 3-fold increased prevalence for simple renal cysts, suggesting a common pathophysiologic pathway, according to research results published in Annals of Vascular Surgery. Patients with simple renal cysts could be at a higher risk for AAA and earlier screening may be beneficial in this population.

Previous studies have found evidence of a higher prevalence of AAA among patients with polycystic kidney disease. An imbalance in proteases vs antiproteases causing the proteolytic process that damages connective tissue is thought to be the pathogenic mechanism that affects the abdominal wall, lungs, thoracic aorta, and kidneys. For that reason, pathogenic mechanisms involving metalloproteinases are hypothesized to play an important role in the development of AAA.

To prove this, a team of investigators conducted a systemic review to determine whether AAA and simple renal cysts share a common pathogenic mechanism even though they are distinct clinical findings and to determine whether AAA is linked to a higher prevalence for simple renal cysts.

The researchers compiled 11 retrospective studies (9 comparative and 3 single-arm studies) that enrolled 2297 patients with AAA and 35,873 patients without AAA who underwent computed tomography angiography as a screening or pre-evaluation other than for AAA.

Patients who were men (odds ratio [OR], 1.88; P =.002) and patients with dyslipidemia (OR, 1.85; P =.017) were more likely to have AAA. Conversely, the prevalence of diabetes was lower among patients with AAA compared with those who did not have AAA (OR, 0.65; P <.001). Coronary artery disease, hypertension, pulmonary disease, and smoking history were all present in both cohorts at similar rates.

Among patients with and without AAA (including patients in the single-arm studies), the cumulative incidence of simple renal cyst was 55% and 32%, respectively, suggesting a significant association between AAA and incidence of simple renal cysts (OR, 3.02; P <.001). In a sensitivity analysis excluding the study with the largest sample size, there was still a significant prevalence of simple renal cyst among patients with AAA (OR, 2.71; P <.001).

“Based on the results of this meta-analysis patients with [simple renal cyst] should be considered at high risk for AAA formation and therefore an earlier AAA screening would be reasonable,” the researchers noted. “However, future studies should further evaluate our results and determine whether [simple renal cysts] are associated with higher risk for AAA growth and/or rupture,” the investigators concluded.

Disclosure: One author declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.

Reference

Giannopoulos S, Kokkinidis DG, Avgerinos ED, Armstrong EJ. Association of abdominal aortic aneurysm and simple renal cysts: a systematic review and meta-analysis. Ann Vasc Surg. 2021:S0890-5096(21)00129-1. doi:10.1016/j.avsg.2021.01.075