Preoperative statin therapy is associated with improved outcomes and resource utilization in patients undergoing aortic aneurysm repair

From the New England Society for Vascular Surgery

Preoperative statin therapy is associated with improved outcomes and resource utilization in patients undergoing aortic aneurysm repair Michael M. McNally, MD, Steven C. Agle, MD, Frank M. Parker, DO, William M. Bogey, MD, Charles S. Powell, MD, and Michael C. Stoner, MD, Greenville, NC Introduction: This study hypothesized that preoperative statin therapy would have a protective effect on patients undergoing elective abdominal aortic aneurysm (AAA) repair and that the risk-reduction effect of these agents would result in a reduction in subsequent total hospital costs. Methods: All patients who underwent an elective endovascular AAA repair (EVAR) or open AAA repair (OAR) between 2004 and 2007 were retrospectively reviewed. Clinical end points included postoperative days, length of hospital stay, postoperative complications (myocardial infarction, stroke, renal failure, hemorrhage, pneumonia, urinary tract infection, wound infection), and 30-day mortality. The financial end point was total hospital cost associated with the procedure. Results: We identified 401 patients, consisting of 173 EVAR patients (43%) and 228 OAR (57%). Despite a higher Society for Vascular Surgery risk score, the EVAR statin cohort had significantly reduced postoperative days (1.9 ⴞ 0.2 vs 2.3 ⴞ 0.3, P < .05) and hospital length of stay (2.3 ⴞ 0.3 vs 2.8 ⴞ 0.4, P < .05) compared with the nonstatin EVAR cohort. Postoperative complications (4.4% vs 14.7%, P < .05) and the mortality rate (0.0% vs 5.9%, P < .05) were significantly decreased in the OAR statin cohort compared with the nonstatin OAR cohort and trended to be decreased in the EVAR statin group. Statin therapy translated into a lower total cost per patient of $3,205 for EVAR and $3,792 for OAR (P < .05). Conclusion: With respect to both clinical outcome measures and subsequent resource utilization, statin therapy is associated with a beneficial effect in patients undergoing elective AAA repair. These data suggest that preoperative statin therapy should be an integral part of the risk optimization for patients undergoing AAA repair. ( J Vasc Surg 2010;51:1390-6.)

Total health care spending, which consumed approximately 8% of the 1975 United States economy, currently accounts for 16% of the gross domestic product and the share estimate is projected to reach nearly 20% by 2016. Publically financed Medicare and Medicaid spending is predicted to encompass 5.9% of the gross domestic product by 2017 and up to 20% by 2050.1 Within this context, care-process improvement becomes an avenue for physiciandriven health care reform. Specifically, careful case selection, patient optimization, meticulous surgical technique, and proper implementation of care pathways will yield better clinical outcomes, which in turn will improve resource utilization. With this in mind, we reviewed our contemporary experience with elective open and endovascular treatment of abdominal aortic aneurysm (AAA) disease to investigating the protective role of preoperative statin therapy in patients undergoing elective AAA repair. Clinical and fiFrom the Department of Cardiovascular Sciences, East Carolina University. Competition of interest: none. Presented at the Thirty-sixth Annual Meeting of the New England Society for Vascular Surgery, Boston, Mass, Oct 2-4, 2009. Reprint requests: Michael C. Stoner, MD, RVT, FACS, Associate Professor, East Carolina University, Brody School of Medicine, Department of Cardiovascular Sciences, Greenville, NC 27858-4354 (e-mail: stonerm@ ecu.edu). The editors and reviewers of this article have no relevant financial relationships to disclose per the JVS policy that requires reviewers to decline review of any manuscript for which they may have a competition of interest. 0741-5214/$36.00 Copyright © 2010 by the Society for Vascular Surgery. doi:10.1016/j.jvs.2010.01.028

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nancial data were assessed to test our hypothesis that preoperative statins have beneficial effects in elective AAA repair that improve clinical outcomes and result in a decrease in costs and in improvements in hospital bed resource utilization. METHODS This study was approved by the University and Medical Center Institutional Review Board of East Carolina University. Patient selection and data collection. A retrospective computerized database was used to identify all patients with infrarenal AAAs who had undergone elective, nonruptured, open (OAR) or endovascular repair (EVAR) from July 2004 to July 2007. Patients were identified using the hospitals’ billing database using appropriate Common Procedural Terminology (CPT) codes (OAR 35081, 35102; EVAR 34800-34826). The operative and clinical notes were reviewed, and nonelective cases were excluded. The decision to use OAR or EVAR was based on clinical evaluation, anatomic factors, and the attending surgeon’s preference. Preoperative, procedural, and outcome variables were collected from the computerized patient care records. Basic demographic data were recorded, omitting patient identifying information. Preoperative computed tomography images were reviewed to determine the size of the AAA, using the axial images, measuring the maximal minor axis adventitial-to-adventitial distance of the infrarenal aorta. Patients who presented with a complaint of abdominal or back pain

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and a tender, pulsatile abdominal mass on physical examination were considered symptomatic. Patient comorbidities were defined as: ●

●

● ●

●

● ● ●

●

diabetes mellitus: medical treatment of diabetes with insulin, oral hypoglycemic agents, dietary care, or any combination thereof; hypertension: elevated blood pressure (⬎140/90 mm Hg) at the time of the initial evaluation or medical treatment of hypertension; hypercholesterolemia: medical treatment of dyslipidemia or total cholesterol ⬎200 mg/dL; smoking/tobacco use: recorded as both lifetime tobacco use (history) and tobacco use at the time of operation (current); coronary artery disease: medical therapy for coronary vascular disease, anatomic diagnosis by axial imaging or catheterization, or by prior coronary revascularization; renal insufficiency: serum creatinine ⬎1.5 mg/dL; end-stage renal disease: renal failure requiring continuing renal replacement therapy; chronic obstructive pulmonary disease (COPD): prior diagnosis of obstructive pulmonary process or ongoing medical therapy for such; and Society for Vascular Surgery (SVS)/American Association for Vascular Surgery (AAVS) risk score: based on the comorbid profiles, patients were assigned a risk score as described by Chaikof et al.2

Perioperative medical management (medication at the time of outpatient referral) was noted with respect to the following agents: ● ● ● ●

antiplatelet therapy: aspirin or clopidogrel (Plavix, Sanofi-Aventis, Bridgewater, NJ); statin therapy: use of any 3-hydroxy-3-methyl-glutarylcoenzyme A reductase inhibitor or combination agent; ␤-blocker: use of a ␤-adrenergic receptor antagonist or combination agent, regardless of selectivity; angiotensin blockade: an angiotensin-converting enzyme inhibitor (ACEI) or angiotensin receptor blocker (ARB).

OAR procedures. All OAR procedures took place in a cardiovascular operating room with the patient under a general anesthetic and an epidural catheter for postoperative analgesia. The aortic replacement took place by a transperitoneal inframesocolic aortic exposure or a left retroperitoneal exposure, at the discretion of the attending surgeon. Before aortic clamp placement, patients were systemically heparinized, and appropriate pharmacologic afterload reduction was undertaken. Protamine sulfate was given to reverse systemic heparinization, and a combination of autologous and donor blood products were used as appropriate. Patients were admitted to an intensive care unit and transferred to an intermediate care unit typically ⱕ24 hours. During their stay, patients were cared for using a standard postoperative care pathway, which included the

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use of aspirin and ␤-blockers for cardiovascular risk reduction, regardless of preoperative use. EVAR procedures. Preoperative planning used computed tomography scan with administration of intravenous iodinated contrast. Device selection was the decision of the attending surgeon. General anesthesia was used for most procedures. After dissection of the femoral arteries, the patient was systemically heparinized, and the stent graft was deployed according to the device-specific indications for use. After completion, protamine sulfate was administered, and a combination of autologous and donor blood products were used as needed. Patients were admitted to an intermediate care unit, and a standard care pathway was instituted, which included the use of postoperative aspirin and ␤-blockers, regardless of preoperative use. Outcomes. The following initial hospitalization outcomes variables were recorded for each patient: ● ● ● ● ● ●

●

● ● ● ●

death: 30-day all-cause mortality (or inpatient mortality if length of stay ⬎30 days); myocardial infarction: electrocardiographic or biomarkerpositive sign of myocardial injury; renal failure: use of renal replacement therapy in patients not already requiring dialysis; stroke: central neurologic deficit lasting ⬎24 hours; pneumonia: radiographic findings of pneumonia and antibiotic course of treatment; urinary tract infection: urinalysis or urine culture demonstrating a bacterial infection and antibiotic course of treatment; wound complication: any wound issue including seroma, cellulitis with antibiotic treatment, wound infection requiring incision and drainage, or wound dehiscence; estimated blood loss from anesthesia record; length of stay: total number of hospital days associated with the index case; postoperative stay: total number of hospital days after the index case; and total cost (in US dollars): summation of direct and indirect hospital costs associated with the admission, including any secondary procedures or complicationrelated expenses. Cost data were obtained from an institutional inpatient billing database and were derived from accepted standard methodology for hospital surgical service line-cost determinations.

Statistical analysis. The study population was stratified by operative procedure, and univariate statistical methods (t test or ␹2 analysis) were used to examine differences in preoperative variables and postoperative outcomes. A multivariate (logistic regression) analysis was used to analyze the categoric variables associated with the occurrence of any of the listed complications. Variables with a value of P ⬍ .10 were considered candidates for this model. To examine the protective effect of preoperative statin therapy, patients were stratified by treatment modality and statin use, and univariate techniques were used to examine the

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Table I. Characteristics of patients undergoing elective open or endovascular abdominal aortic aneurysm repair Characteristicsa

Open (n ⫽ 228)

Table II. Outcomes of patients undergoing elective open or endovascular abdominal aortic aneurysm repair

Endovascular (n ⫽ 173) Outcomes

Demographics Age, y Male Clinical Hypertension COPD Coronary artery disease Diabetes Smoking-history Smoking-current Creatinine, mg/dL Dialysis Hypercholesterolemia SVS/AAVS risk score Medical treatment Antiplatelet Statin ␤-blocker ACEI/ARB Indication AAA size, cm Symptoms

69.3 ⫾ 0.5 82.5

72.8 ⫾ 0.6b 81.0

77.6 17.1 37.3 13.6 77.2 42.9 1.21 ⫾ 0.04 0 52.8 6.4 ⫾ 0.3

77.5 21.4 44.5 19.7 70.6 37.1 1.47 ⫾ 0.10 5.2b 53.1 7.7 ⫾ 0.3

38.6 40.4 34.7 42.9

40.2 51.4c 51.0c 43.9

5.9 ⫾ 0.1 9.7

5.5 ⫾ 0.1 14.5

AAA, Abdominal aortic aneurysm; AAVS, American Association for Vascular Surgery; ACEI, angiotensin-converting enzyme inhibitor; ARB, angiotensin receptor blocker; SVS, Society for Vascular Surgery. a Continuous data are presented as the mean ⫾ standard deviation; categoric data as %. b P ⬍ .01. c P ⬍ .05.

association of preoperative and postoperative variables based on statin therapy and comparing patients with the same treatment modality. A value of P ⬍ .05 was considered significant for all statistical analyses. Data were analyzed using SAS 9.1 software (SAS Institute Inc, Cary, NC). RESULTS During the study period, 401 patients underwent elective repair for an infrarenal AAA; of these, 228 (57%) had OAR and 173 (43%) had EVAR. The EVAR and OAR groups were well matched, with no significant differences in the clinical variables of gender, AAA size, symptoms, hypertension, COPD, coronary artery disease, diabetes, hypercholesterolemia, and smoking history. The significant differences seen between the two groups were that the EVAR cohort was older, and patients with end-stage renal disease were only offered EVAR repair. Preoperative medical treatment occurring at least 30 days before AAA repair showed significantly higher statin and ␤-blocker use in the EVAR group (Table I). To address potential practice pattern changes over time, the cohorts were dichotomized into early or late periods based on the midpoint time. In the early period, OAR was more commonly used (61.3% vs 38.7%, P ⬍ .001). Preoperative ␤-blockade was also lower in early OAR

Clinical Death Myocardial infarction Renal failure Stroke Pneumonia Urinary tract infection Wound infection Any complication

Open (n ⫽ 228) %

Endovascular (n ⫽ 173) %

3.5 2.1 2.2 0 4.0 2.2 3.5 10.5 Mean ⫾ SD

1.7 1.1 1.7 0 0 0 1.7 4.7 Mean ⫾ SD

Procedural/resource utilization Estimated blood loss, mL 1093 ⫾ 54.7 272 ⫾ 21.8a Length of stay, d 8.7 ⫾ 0.4 2.5 ⫾ 0.2a Postoperative stay, d 7.6 ⫾ 0.3 2.2 ⫾ 0.2a Total cost, $ 20,876 ⫾ 1059 34,837 ⫾ 807a SD, Standard deviation. a P ⬍ .01.

patients compared with later cases (29.3% vs 48.4%, P ⬍ .01). There was no significant change in ␤-blocker use in EVAR patients over time, and there was no significant difference in statin use over time for OAR or EVAR patients. An analysis of outcomes between the OAR and EVAR groups found no significant differences in clinical end points. The 30-day mortality rate and cardiovascular postoperative complications, which include myocardial infarction, renal failure, and stroke, demonstrated no statistically significant difference. However, numerous significant differences in procedural and resource utilization were seen between groups. Estimated blood loss was about five times less in EVAR patients than in OAR patients (272 vs 1093 mL; P ⬍ .01). For hospital resource utilization, EVAR patients had a significantly lower length of stay than OAR patients (2.5 vs 8.7 days; P ⬍0.01). Financially, the total cost associated with the index procedure was $20,876 in the OAR group vs $34,837 in the EVAR group, driven primarily by the device cost differential (P ⬍ .01; Table II). Multivariate analysis to identify possible covariates associated with any complication after elective OAR and EVAR resulted in two significant findings: patients with renal insufficiency (creatinine ⬎1.5 mg/dL) had a high complication rate (odds ratio [OR], 5.86; P ⬍ .001), and preoperative statin therapy had a protective effect from complications (OR ⫽ 0.39, P ⫽ .04; Table III). Multivariate analysis using the same candidate variables for both the OAR and EVAR patients independently also found statin therapy was protective, with ORs of 0.89 for OAR (P ⫽ .04) and 0.21 for EVAR (P ⫽ .02). To investigate the protective effect of statin therapy further, a subgroup analysis examined clinical characteristics, outcomes, and resource utilization in patients undergoing OAR or EVAR repair, stratified by preoperative

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Table III. Multivariate model for the occurrence of any complication after abdominal aortic aneurysm repair in both open and endovascular cohorts Variable

OR

95% CI

P

Age ⬎80 y COPD Coronary artery disease Diabetes Smoker Creatinine ⬎1.5 mg/dL EVAR Antiplatelet Statin ␤-blocker ACEI/ARB

1.82 1.19 1.01 1.46 0.55 5.86 0.41 0.61 0.39 0.73 1.37

0.64-5.14 0.42-3.31 0.42-2.43 0.52-4.07 0.24-1.29 2.39-14.35 0.16-1.03 0.25-1.50 0.16-0.99 0.29-1.83 0.55-3.39

.25 .73 .98 .46 .16 ⬍.001 .06 .28 .04 .51 .49

ACEI, Angiotensin-converting enzyme inhibitor; ARB, angiotensin receptor blocker; CI, confidence interval; COPD, chronic obstructive pulmonary disease; EVAR, endovascular aneurysm repair; OR, odds ratio.

statin use. Although the OAR statin patients had significantly higher SVS risk scores, they had a lower 30-day mortality and complication rate of 0.0% and 4.4% vs 5.9% and 14.7%, respectively (P ⬍ .05). With respect to hospital resource utilization, the patients receiving statin therapy undergoing EVAR had a significantly shorter postoperative stay and length of stay. Financially, statin therapy translated into improved total cost per patient of $3,792 for OAR and $3,205 for EVAR (P ⬍ .05; Table IV). Further analysis showed that these findings were regardless of preoperative ␤-blockade, renin-angiotensin system inhibitors, antiplatelet therapy, cholesterol level, and smoking status. Within both the OAR and EVAR groups, when stratified by statin therapy and analyzed by multivariate analysis, there was no significant difference with respect to the other preoperative medical therapies with antiplatelet, ␤-blockade, or angiotensin blockade. DISCUSSION Statins, or 3-hydroxyl-3-methylglutaryl coenzyme A reductase inhibitors, have known beneficial effects in reducing low-density lipoprotein and total cholesterol levels, decreasing triglyceride levels, and elevating high-density lipoprotein levels.3 However, other pleiotropic effects of statins that affect perioperative outcomes in noncardiac vascular surgery have been described within the last decade.4,5 The beneficial effects of statins on clinical perioperative events involve nonlipidic mechanisms that alter endothelial function, inflammatory responses, atheromatous plaque stability, and thrombus formation.6,7 Evidence examining statin therapy in elective AAA repair is limited. Two level I studies describing the beneficial role of perioperative statins in noncardiac vascular surgery (including AAA surgery) demonstrated reduced postoperative myocardial events in treated patients.8,9 Other studies examining statins specifically in elective AAA repair are few and retrospective in nature.10-12 Most studies of statins and AAA are observational and investigate AAA

surveillance and examine aortic growth rates in patients with and without statin therapy.13-16 Furthermore, none examine the financial effect of these lipid-lowering agents, whose continued use in noncardiac surgery is advocated in the American Heart Association guidelines.17 With AAAs encompassing the 13th and 16th leading causes of death, respectively, in men and women aged ⬎65 years old in the United States and approximately 35,000 to 40,000 AAAs being repaired annually, the effect of existing perioperative therapies should be optimized.18-21 From its original description less than 20 years ago, endovascular repair is now the most common modality for repairing AAAs.22-24 Therefore, studies such as this are necessary to highlight the importance of the care process in both traditional open and endovascular elective AAA repair. The purpose of this study was to analyze the effect of preoperative statin therapy in elective AAA repair. Importantly, other preoperative medications such as reninangiotensin system inhibitors, antiplatelet therapy, and ␤-blockade did not have the same effect as statins in multivariate analysis for the occurrence of any postoperative complication. A potential confounder in this analysis is the widespread use of postoperative aspirin and ␤-adrenergic blockade in our institutional care pathway, which may obviate the preoperative benefit attributable to these drugs. Because of the size of the study, we do not have data on the relative efficacy of various statin agents. Furthermore, we do not have data to address the potential benefit of longerterm (⬎30 days) statin use before AAA repair. The patients in the EVAR cohort in our study were older than the OAR patients and had an equivalent profile of medical diagnoses, with the exception of end-stage renal disease requiring dialysis. Because of our institutional policy of preoperative risk stratification, all patients who required chronic dialysis were offered only EVAR (when anatomically feasible). When stratified by statin use, the statin EVAR group had a significantly decreased length of stay and postoperative number of days in the hospital. One possible explanation for the decreased resource utilization is the reduction in the overall complication rate, although this complication rate did not reach statistical significance. Notably, there were no 30-day deaths in the statin EVAR group despite equal rates of myocardial infarction between cohorts. This may be attributed to the protective benefit of these agents in the coronary vascular bed and their ability to limit the extent of myocardial ischemic injury.25 Elective OAR patients had higher overall complication rates than EVAR patients. The physiologic stress of the operation contributed to this higher complication rate, including noncardiovascular events such as urinary tract infection, pneumonia, and wound infection. When patients were stratified by preoperative statin therapy, clinical outcomes were significantly improved in the statin cohort, with a 4.4% complication rate vs 14.7% in nonstatin patients (P ⬍ .05). When only potential cardiovascular complications were grouped, such as myocardial infarction, stroke, or renal failure, there was still a significant difference seen in the preoperative statin group (P ⬍ .04). Most notably,

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Table IV. Clinical characteristics, outcomes, and resource utilization in patients undergoing open or endovascular AAA repair, stratified by preoperative statin use Open (n ⫽ 228) Characteristica Clinical Age, y COPD CAD Diabetes Creatinine, mg/dL SVS/AAVS risk score Outcomes Death Myocardial infarction Renal failure Any complication Resource utilization Length of stay, d Postop stay, d Total cost, $

Endovascular (n ⫽ 173)

Statin (n ⫽ 92)

No statin (n ⫽ 136)

Statin (n ⫽89)

No statin (n ⫽ 84)

68.1 ⫾ 0.7 15.2 51.1b 14.1 1.2 ⫾ 0.1 7.3 ⫾ 0.4c

70.1 ⫾ 0.7 18.4 27.9 13.2 1.2 ⫾ 1.0 5.9 ⫾ 0.3

70.8 ⫾ 0.8 22.5 38.7 20.0 1.3 ⫾ 0.1 7.9 ⫾ 0.4c

71.5 ⫾ 1.0 20.2 48.3 19.1 1.5 ⫾ 0.2 7.2 ⫾ 0.5

0.0c 0.0 0.0 4.4c

5.9 3.7 3.7 14.7

0.0 1.1 1.2 4.4

3.6 1.1 2.3 4.8

8.2 ⫾ 0.6 7.2 ⫾ 0.6 18,647 ⫾ 1231c

9.1 ⫾ 0.5 7.8 ⫾ 0.5 22,440 ⫾ 1572

2.3 ⫾ 0.3c 1.9 ⫾ 0.2c 33,237 ⫾ 1041c

2.8 ⫾ 0.4 2.3 ⫾ 0.3 36,442 ⫾ 1274

AAVS, American Association for Vascular Surgery; CAD, coronary artery disease; COPD, chronic obstructive pulmonary disease; SVS, Society for Vascular Surgery. a Continuous data are presented as mean ⫾ standard deviation; categoric data as percentage. b P ⬍ .01. c P ⬍ .05.

again, was the 0% mortality in the statin patients, which we postulate to be related to the atheromatous plaquestabilizing features of statins. There is a paucity of literature regarding the financial effect of preoperative statin therapy in AAA repair. Simply comparing total costs associated with the index procedure between treatment modalities shows an increased cost in the EVAR group, which parallels recent economic evaluations from randomized trials.26,27 Unique to our study stands the economic analysis stratified by a preoperative medication. Significant differences in total cost savings were seen in the statin cohorts in both AAA repair groups compared with patients not taking preoperative statins. In particular, $3792 was saved in elective OAR patients and $3205 in each elective EVAR patient. Extrapolation of these cost-savings to a typical high-volume AAA center yields a substantial potential annual cost-benefit. For instance, a recent National Inpatient Sample study defined a high-volume AAA institution with the following criteria: elective OAR ⬎29 cases and elective EVAR ⬎40 cases. Based on these case numbers, a high-volume center with a similar case mix would expect that ubiquitous statin therapy would result in a maximal potential savings of $241,960 annually.28 Another important facet of this study was the multivariate analysis that identified renal insufficiency as a correlate of untoward outcomes. The strong association of renal insufficiency with poor outcomes in aortic surgery has been well documented in the literature and is hardly unique to this database.2,29 The strong odds ratios demonstrated in the logistic regression model argue for strict case selection in this subgroup of patients and ardent adherence to best-

practice standards to mitigate complications in this highrisk group. The primary flaw of this study lies in the sample database. The data are from a single institution, collected in a retrospective manner and therefore demonstrate biases inherent to any individual practice pattern. Because of the several-year span of the database, there was a heterogenous application of EVAR (more common in late cases) and use of ␤-blockade in OAR patients (again, more common over time). Both of these factors may blunt the potential protective benefit of statin therapy in OAR patients and result in an understated protective benefit in this cohort. Furthermore, the conclusions from this analysis are based on a relatively small group of patients, and therefore the risk of statistical error is significant. In reference to statin stratification between EVAR and OAR, all patients included in the statin groups were taking their medications ⱕ30 days of the aortic surgery; however, the length of time individuals were receiving preoperative statin therapy and the dose requirement is unknown. Additionally, we have noted the total cholesterol level, not the patient’s preoperative lipid profile, when defining hypercholesterolemia. The lipid profile components also represent an uncontrolled variable. Finally, the financial analysis is limited. It only includes total costs associated with index procedure hospitalization and does not account for long-term reintervention or patient quality of life. Another potential confounder in this study is that a patient taking a statin drug may be a correlate of better primary medical care. We noted that the penetrance of ␤-blockade, angiotensin blockade, and antiplatelet therapy

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was not statistically different between statin and nonstatin patients, which at least suggests equal access to primary medical care between the groups. However, the nonstatin patients might not have been receiving optimal evidencebased primary medical care and could have been carrying a higher incidence of occult coronary disease, which could explain the inferior outcomes in this group. Overall statin use in this study was quite low (40.4% OAR, 51.4% EVAR), which does suggest heterogeneity with respect to the quality of medical care these patients were receiving before referral. Within the confines of a retrospective analysis, it is difficult to address this point. Still, there is a strongly suggestive amount of evidence to support a protective role for statin drugs in this group of patients and to support our hypothesis. Finally, it is important to note the relatively low percentage of patients receiving appropriate medical therapy at the time of referral. This is likely related to the low socioeconomic status and geographic barrier to care seen in rural academic practices such as ours. On the basis of these data, we have taken a more aggressive stance on preoperative statin therapy in patients undergoing AAA repair. In the past, it was not our practice to start patients on statins; rather, this was communicated back to the referring or primary doctor at the time of consultation. Currently, we initiate statin pharmacotherapy in all elective AAA patients at the initial consultation, based on the class II American Heart Association guidelines, unless there is a specific contraindication, regardless of preoperative lipid profile.17 The therapy is continued through the operation until the first postoperative visit. At that time, we communicate a recommendation to continue medical therapy with the patient’s primary care physician. We are currently following this practice change in a prospective manner and will report on its impact. CONCLUSION With increasing demands on the health care system to provide care in a cost-effective manner, this study demonstrates an example of preoperative optimization in the care process for AAA. Statin treatment is correlated with improved patient outcomes, which cumulate in lower overall health care costs. The benefits associated with preoperative statin therapy occurred regardless of the treatment modality. On the basis of these data, we recommend statin therapy as an essential component in the preoperative regimen for all patients undergoing elective AAA repair. AUTHOR CONTRIBUTIONS Conception and design: MM, SA, FP, WB, CP, MS Analysis and interpretation: MM, MS Data collection: MM, SA, MS Writing the article: MM, MS Critical revision of the article: MM, SA, FP, WB, CP, MS Final approval of the article: MM, SA, FP, WB, CP, MS Statistical analysis: MM, SA, MS Obtained funding: MS Overall responsibility: MS

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