Beneficial effect of statins on total mortality in abdominal aortic aneurysm (AAA) repair

In this single center, retrospective cohort study we wished to compare early and total mortality for all patients treated for abdominal aortic aneurysms (AAA) with open surgery who were taking statins compared to those who were not. A cohort of 640 patients with AAA was treated with open surgery between 1999 and 2012. Patients were consecutively recruited from a source population of 390,000; 21.3% were female, and the median age was 73 years. The median follow-up was 3.93 years, with an interquartile range of 1.79-6.58 years. The total follow-up was 2855 patient-years. An explanatory strategy was used. The propensity score (PS) was implemented to control for selection bias and confounders. The crude effect of statin use showed a 78% reduction of the 30-day mortality. A stratified analysis using the Mantel-Haenszel method on quintiles of the PS gave an adjusted effect of the odds ratio equal to 0.43 (95% CI: 0.18-0.96), indicating a 57% reduction of the 30-day mortality for statin users. The adjusted rate ratio was 0.62 (95% CI: 0.45-0.83), indicating a reduction of long-term mortality of 38% for statin users compared to non-users for a median follow-up of 3.93 years. This retrospective cohort study showed a significant beneficial effect of statin use on early and long-term survival for patients treated with open surgery. To be conclusive, our results need to be replicated by a randomized clinical trial.