Effects of Statin and Antiplatelet Therapy on Mortality Rates in Abdominal Aortic Aneurysm Patients
Hunter S. Boudreau, Juliet Blakeslee-Carter, Zdenek Novak, Emily L. Spangler, Adam W. Beck
UAB, Birmingham, AL
Effects of Statin and Antiplatelet Therapy in Isolated Abdominal Aortic Aneurysm Patient Outcomes Repair within the Vascular Quality Initiative
Abstract Background Statin therapy has been associated with improved clinical outcomes in patients undergoing treatment for vascular disease. Current guidelines do not address statin therapy in isolated abdominal aortic aneurysm (AAA) in the absence of other atherosclerotic cardiovascular disease (ACVD). This study aims to describe the long-term mortality effects in AAA patients with and without ACVD who undergo AAA repair.Methods A retrospective review of patients undergoing elective endovascular (EVAR) and open (OAR) in the Society for Vascular Surgery Vascular Quality Initiative between 2003-2020. Long-term mortality was evaluated based on the presence of statin medications at discharge and stratified by groups with and without concomitant antiplatelet (AP) therapy.Results 47,012 cases of AAA repair were identified: 85% EVAR and 15% OAR. Kaplan-Meier (KM) survival analysis for all cohorts are shown in Figure 1. EVAR patients on combined statin/AP therapy had significantly improved survival irrespective of whether they had a known ACVD. Combined statin/AP therapy was protective in Cox Regression analysis for the entire EVAR cohort (HR=.71, p<.001). In the presence of ACVD, patients on statin alone had improved mortality compared to those not on a statin (10.9±0.5 vs 10.5±0.4 years), but worse in comparison to those on combined statin/AP therapy (10.9±0.4 vs 12.2±0.2 years). In the absence of ACVD, patients on statin alone had improved mortality compared to patients not on a statin (8.7±0.5 vs 8.4±0.4 years), but worse in comparison to those on combined statin/AP therapy (8.7±0.5 vs 9.4±0.2 years).
For OAR, combined statin/AP therapy had a protective effect across all subgroups based on Cox Regression (HR=0.67, p=.046). Based on KM analysis, OAR patients with ACVD on combined statin/AP therapy had significantly improved survival compared to isolated statin therapy (12.6±0.5 vs 10±1 years) and no medical therapy (12.6±0.5 vs 10.7±1 years). In KM analysis, OAR patients without known ACVD indications had no significant survival differences based on the presence of statin/AP therapy, but the presence of statin/AP was protective in Cox Regression analysis.
Conclusion Statin therapy is associated with improved survival in AAA patients regardless of the presence of a known ACVD indication. Although we are unable to assess AAA patients in surveillance prior to repair using SVS VQI data, statin therapy has appears to have significant survival benefits even in isolated AAA without ACVD. Addition of this recommendation to current treatment guidelines may be warranted.
Figure 1: Kaplan-Meier survival analysis of surgical cohorts based on presence of known ACVD statin indication.
Back to 2021 Abstracts