Antiplatelet Therapy and Bleeding, Thrombosis, and Aneurysm Growth in Patients with Abdominal Aortic Aneurysms

Recent guidelines recommend considering antiplatelet therapy (class IIb recommendation) for patients with AAAs, but bleeding risk remains a concern. This study aims to investigate the association of antiplatelet therapy with bleeding, thrombosis, and aneurysm growth among patients with AAAs.

A single-center retrospective chart review of patients with AAA identified on imaging (2019-2023) was performed. Demographics and outcomes were compared by antiplatelet status, and multivariable regression identified factors associated with mortality, MACE, bleeding, and AAA growth.

Among 886 (73% male) patients studied, 511 (57.7%) were prescribed antiplatelet therapy. Those prescribed antiplatelet therapy had higher rates of atherosclerotic disease than those not on antiplatelets. Patients not prescribed antiplatelet therapy were more likely to be female, have atrial fibrillation, and be prescribed anticoagulation. At a mean follow-up of 1.8 years, there were no differences in bleeding, major adverse cardiovascular events, venous thromboembolism events, or growth rate associated with antiplatelet prescription. Adjusted analyses showed statins (HR=0.73, p=0.02), but not antiplatelets or anticoagulants, were associated with reduced risk of mortality. Diabetes was associated with decreased AAA growth rate, while larger initial diameter was associated with increased growth rate as well as mortality.

Among patients with AAA, antiplatelet therapy was not observed to be associated with an increase in bleeding risk, but was also not associated with decreased mortality, thrombosis, or aneurysm growth. Statins were observed to be associated with reduced mortality. Aneurysmal growth rate was not associated with any medical therapies studied, including statins, and was only influenced by the presence of diabetes.