Antithrombotic and Lipid Lowering Therapy is Associated With Improved Survival After Vascular Surgery: A Population Based Study From Norway.

Objective: This population based retrospective cohort study aimed to investigate the association between combined treatment with lipid lowering drugs and antiplatelet or anticoagulation therapy and long term survival following vascular surgery in Norway.

Methods: The study included all patients who were registered for the treatment of carotid stenosis, abdominal aortic aneurysm (AAA), and atherosclerotic lower extremity arterial disease (LEAD) in the Norwegian Registry for Vascular Surgery between 2015 and 2019 and who were discharged alive. Clinical and medication details were retrieved from the register. Survival was assessed with Kaplan-Meier analysis and a multivariable Cox regression model. Stratification was according to treatment group, patient sex, and if patients received the recommended medications or not. Recommended medications were defined as lipid lowering drugs, usually statins, and antiplatelets, or sometimes anticoagulants, when comorbidity indicated anticoagulation therapy.

Results: In total, 15 810 patients had LEAD, 4 080 patients AAA, and 2 194 patients had carotid stenosis. In all treatment groups, survival was superior for patients who used the recommended medications upon discharge. The difference was greatest in patients with LEAD with mean survival periods of 4.33 (95% CI 4.29 - 4.36) and 3.7 (95% CI 3.64 - 3.77) years in patients discharged with and without the recommended medications, respectively (p < .001). The mean survival periods were 4.67 (95% CI 4.61 - 4.73) and 4.34 (95% CI 4.24 - 4.44) years in patients with AAA discharged with and without the recommended medications, respectively (p < .001). Cox regression analysis showed a statistically significantly lower mortality rate for patients discharged with the recommended medications for LEAD (HR 0.58; p < .001) and AAA (HR 0.57; p < .001).

Conclusion: The recommended medications were associated with improved survival in all treatment groups and both sexes. The survival difference was statistically significant in patients with LEAD and AAA. Patients with LEAD had the greatest improvement; therefore, the recommended secondary prophylaxis is especially important in these patients.