Zur Behandlung des abdominellen Aortenaneurysmas in Deutschland: Qualitätssicherungsdaten 2013

Regional variation in endovascular treatment rate and in-hospital mortality of abdominal aortic aneurysms in Germany

Summary: Background: Abdominal aortic aneurysms (AAA) can be treated by either open surgery (OAR) or endovascular aortic repair (EVAR). The aim of this study was to analyze regional variations in application of (EVAR) and in-hospital mortality after intact AAA (iAAA) repair. Methods: Using data provided by the German Federal Statistical Office, a nationwide analysis for 2012 to 2014 was conducted. Patients with a diagnosis of iAAA (I71.4) and corresponding procedure codes for OAR (5-384.5/7) or EVAR (5-38a.1) were included. Odds ratios (ORs) for use of EVAR (proportion of EVAR among total EVAR + OAR cases) and mortality were calculated for all regions in Germany. ORs for EVAR use were adjusted for age, sex, and risk (Elixhauser score). ORs for mortality were additionally adjusted for type of procedure (OAR/EVAR). Results: Finally, 31,757 procedures for iAAA were included. Median age of all patients was 73 years (interquartile range 67–78 years) and 87.1 % were male. The mean proportion of EVAR procedures was 72.6 %; however, the application of EVAR for repair of iAAA varied widely depending on region. The lowest unadjusted regional rate of EVAR use was 48.8 %, while the highest was 92.5 %. After adjustment, the lowest regional OR for EVAR use (compared to the nationwide mean) was 0.23 (95 % confidence interval [0.15–0.36]), the highest 5.93 [1.79–19.65]. Overall in-hospital mortality was 2.9 % (OAR 6.2 %; EVAR 1.7 %). The adjusted regional OR for mortality ranged from 0.31 [0.07–1.42] to 4.98 [2.08–11.93]. Conclusions: This study reveals variations in use of EVAR and in-hospital mortality for iAAA treatment in Germany. This may imply that selection of treatment might not only be influenced by patient characteristics, but also by regional location. These results need to be taken into account when discussing centralization of AAA treatment in Germany.

[The DIGG risk score : A risk predictive model of perioperative mortality after elective treatment of intact abdominal aortic aneurysms in the DIGG register]

OBJECTIVE

The aim of the study was to develop a specific risk score for the aortic register of the German Institute for Vascular Health Care Research (DIGG) of the German Society for Vascular Surgery and Vascular Medicine (DGG) for the prediction of postoperative mortality in elective treatment of intact abdominal aortic aneurysms (iAAA). The score should also enable a risk-adjusted presentation of the register results in the near future.

METHODS

The method of binary logistic regression analysis was used to calculate the model. The data from 10,404 patients were included in the analysis, of whom 7870 (75.6%) were treated by endovascular (EVAR) and 2534 (24.4%) by open (OR) aortic repair. It was examined which factors have an independent influence on hospital mortality and the effect size was determined as a score.

RESULTS

For EVAR, the influencing factors with their effect sizes (score in brackets) were: age >85 years (2), female gender (2), juxtarenal AAA (5), maximum diameter >65 mm (2), diabetes mellitus (2), American Society of Anesthesiologists (ASA) score >3 (2), cardiac comorbidities (3) and renal insufficiency stage >3 (5). For OR the factors were: age >80 years (2), female gender (2), juxtarenal AAA (2), ASA score >3 (3), previous myocardial infarction (2), renal comorbidities (3) and previous stroke (2). The estimated hospital mortality was calculated for the individual case from the sum of the risk factors (scores). The accuracy of the model (correlation between observed and expected results) was determined using the receiver operating characteristic (ROC) curve. An area under the curve (AUC) of 0.817 (confidence interval 0.789-0.844) demonstrated an excellent discrimination. In a validation group of 3831 patients, the good agreement between observed and calculated results was confirmed.

CONCLUSION

The DIGG risk score can predict risk-adjusted hospital mortality after EVAR and OR of iAAA in the DIGG register. Improvements with respect to the prediction are desirable for OR and should be strived for by extending the model in the future.

Reporting of Complications and Mortality in Relation to Risk Communication in Patients with an Abdominal Aortic Aneurysm: A Systematic Review

OBJECTIVES

High-quality reporting of surgical risks is necessary for evidence-based risk communication in clinical practice. Risk communication is defined as the process of discussing benefits and harms of treatment options with patients. This review addressed the current quality of reporting of complications and mortality in publications on abdominal aortic aneurysm treatment, with a focus on items relevant to risk communication.

DESIGN

A systematic review.

MATERIALS

Randomised clinical trials, comparative observational studies and registries from 2010 onwards were eligible if they reported complications and/or mortality in patients with an asymptomatic abdominal aortic aneurysms who received primary treatment.

METHODS

Quality of reporting was assessed by scoring items relevant to risk communication from the reporting standards of the Society for Vascular Surgery (SVS) and the Consolidated Standards of Reporting Trials (CONSORT) statement. Screening, quality assessment and data extraction were independently undertaken by two authors.

RESULTS

Forty-seven publications were included. Nine of 47 publications (19%) provided no definition of complications. In 14 of 47 publications (30%), it was unclear whether the number of adverse events or the number of patients with adverse events were presented. Absolute risk differences were provided in 1 of 32 publications (3.1%) that compared complications between two treatment options. Forty-six of 47 publications reported mortality, of which 42 reported overall mortality rates (91%). Absolute risk differences were given in 2 of the 31 publications (6.5%) that compared mortality between two treatment options.

CONCLUSIONS

The quality of reporting of complications and mortality following primary abdominal aortic aneurysm treatment varied considerably. Better adherence to the SVS reporting standards and the CONSORT statement, as well as stating absolute risk differences may improve the quality of reporting and facilitate evidence-based risk communication.