Christian-Alexander Behrendt

Objective
There is some evidence that weekend admission to the hospital is associated with worse outcomes compared with weekday admission. However, only a few studies have focused on weekend vs weekday surgery outcomes. This study aimed to determine whether there is a weekend effect on outcomes in the treatment of ruptured aortic aneurysms in Germany.

Methods
Health insurance claims of Germany's third largest insurance provider, DAK-Gesundheit, were used to investigate short-term… Show more

Objective
There is some evidence that weekend admission to the hospital is associated with worse outcomes compared with weekday admission. However, only a few studies have focused on weekend vs weekday surgery outcomes. This study aimed to determine whether there is a weekend effect on outcomes in the treatment of ruptured aortic aneurysms in Germany.

Methods
Health insurance claims of Germany's third largest insurance provider, DAK-Gesundheit, were used to investigate short-term and long-term mortality after weekend vs weekday treatment of ruptured aortic aneurysm. Patients undergoing endovascular repair (ER) or open surgical repair (OSR) between January 2008 and December 2016 were included in the study. Both propensity score matching and regression methods were used to adjust for confounding.

Results
There were 1477 patients in the cohort, of whom 517 (35.0%) underwent ER and 960 (65.0%) OSR. Overall, 995 (67.4%) patients underwent an operation on weekdays (Monday to Thursday), and 482 (32.6%) patients underwent an operation on a weekend (Friday to Sunday). In multivariable models, patients who underwent an operation on a weekend were at higher risk of in-hospital death after OSR (49.2% vs 38.0%; odds ratio [OR], 1.61; P = .001), and there was a trend toward higher in-hospital mortality after ER (29.5% vs 21.2%; OR, 1.55; P = .056). The ER of thoracic or thoracoabdominal aortic ruptures was associated with significantly higher in-hospital mortality compared with ER of abdominal aortic aneurysm (OR, 1.69; P = .026).

Conclusions
Weekend repairs of ruptured aortic aneurysms are associated with worse in-hospital survival compared with weekday surgery. ER of thoracic or thoracoabdominal aortic ruptures is associated with worse in-hospital survival compared with ER of ruptured abdominal aortic ruptures. This might be an international phenomenon requiring joint learning and action in times of centralization of aortic procedures. Show less

Objective/Background
Colonic ischaemia (CI) is a severe complication following abdominal aortic aneurysm (AAA) repair, leading to high morbidity and mortality. The aim of the study was to determine the incidence, predictors, and outcomes of CI following AAA repair.

Methods
National claims from Germany's third largest insurance provider, DAK-Gesundheit, were used to investigate CI after intact (iAAA) and ruptured (rAAA) AAA repairs. Patients undergoing endovascular (EVAR) or open… Show more

Objective/Background
Colonic ischaemia (CI) is a severe complication following abdominal aortic aneurysm (AAA) repair, leading to high morbidity and mortality. The aim of the study was to determine the incidence, predictors, and outcomes of CI following AAA repair.

Methods
National claims from Germany's third largest insurance provider, DAK-Gesundheit, were used to investigate CI after intact (iAAA) and ruptured (rAAA) AAA repairs. Patients undergoing endovascular (EVAR) or open surgical (OSR) repairs between January 2008 and December 2017 were included in the study.

Results
There were 9145 patients (8248 iAAA and 897 rAAA) undergoing EVAR or OSR procedures and the median follow up was 2.28 years. Most patients were male (79.2% iAAA, 79.3% rAAA); the median age was 73.0 years (iAAA group) and 76.0 years (rAAA group). Overall, CI occurred 97 (1.2%) times after iAAA and 95 (10.6%) after rAAA. In univariable analyses CI occurred less often after EVAR than after OSR (0.6% vs. 3.7%; p < .001). Acute post-operative renal and respiratory insufficiencies were also related to the occurrence of CI (p < .001). CI was associated with greater in hospital mortality (42.2% vs. 2.7% for iAAA, 64.2% vs. 36.3% for rAAA; p < .001) and lower long-term survival for iAAA (Kaplan–Meier analysis). In multivariable analyses, rAAA (odds ratio [OR] 5.59), and higher van Walraven comorbidity score (OR 1.09) were independently associated with greater risk of CI occurrence. EVAR use (OR 0.30) was protective. EVAR use remained protective in stratified analyses within iAAA (OR 0.32) and rAAA (OR 0.26).

Conclusion
Post-operative CI after AAA repair is not common but is associated with worse in hospital outcomes and lower long-term survival. EVAR was protective after both rAAA and iAAA repairs. When discussing the treatment of AAA with patients the protective effect of EVAR should be considered. Future studies should validate predictive scores and advance preventive strategies. Show less

Objectives
To study international differences in incidence and practice patterns as well as time trends in lower limb amputations related to peripheral arterial disease and/or diabetes mellitus.

Methods
Data on lower limb amputations during 2010–2014 were collected from population based administrative data from countries in Europe and Australasia participating in the VASCUNET collaboration. Amputation rates, time trends, in hospital or 30 day mortality and reimbursement systems… Show more

Objectives
To study international differences in incidence and practice patterns as well as time trends in lower limb amputations related to peripheral arterial disease and/or diabetes mellitus.

Methods
Data on lower limb amputations during 2010–2014 were collected from population based administrative data from countries in Europe and Australasia participating in the VASCUNET collaboration. Amputation rates, time trends, in hospital or 30 day mortality and reimbursement systems were analysed.

Results
Data from 12 countries covering 259 million inhabitants in 2014 were included. Individuals aged ≥ 65 years ranged from 12.9% (Slovakia) to 20.7% (Germany) and diabetes prevalence among amputees from 25.7% (Finland) to 74.3% (Slovakia). The mean incidence of major amputation varied between 7.2/100,000 (New Zealand) and 41.4/100,000 (Hungary), with an overall declining time trend with the exception of Slovakia, while minor amputations increased over time. The older age group (≥65 years) was up to 4.9 times more likely to be amputated compared with those younger than 65 years. Reported mortality rates were lowest in Finland (6.3%) and highest in Hungary (20.3%). Countries with a fee for service reimbursement system had a lower incidence of major amputation compared with countries with a population based reimbursement system (14.3/100,000 versus 18.4/100,000, respectively, p < .001).

Conclusions
This international audit showed large geographical differences in major amputation rates, by a factor of almost six, and an overall declining time trend during the 4 year observation of this study. Diabetes prevalence, age distribution, and mortality rates were also found to vary between countries. Despite limitations attributable to registry data, these findings are important, and warrant further research on how to improve limb salvage in different demographic settings. Show less

Background
To achieve consensus on the minimum core data set for evaluation of peripheral arterial revascularisation outcomes and enable collaboration among international registries.
Methods
A modified Delphi approach was used to achieve consensus among international vascular surgeons and registry members of the International Consortium of Vascular Registries (ICVR). Variables, including definitions, from registries covering open and endovascular surgery, representing 14 countries in… Show more

Background
To achieve consensus on the minimum core data set for evaluation of peripheral arterial revascularisation outcomes and enable collaboration among international registries.
Methods
A modified Delphi approach was used to achieve consensus among international vascular surgeons and registry members of the International Consortium of Vascular Registries (ICVR). Variables, including definitions, from registries covering open and endovascular surgery, representing 14 countries in ICVR, were collected and analysed to define a minimum core data set and to develop an optimum data set for registries. Up to three different levels of variable specification were suggested to allow inclusion of registries with simpler versus more complex data capture, while still allowing for data aggregation based on harmonised core definitions.
Results
Among 31 invited experts, 25 completed five Delphi rounds via internet exchange and face to face discussions. In total, 187 different items from the various registry data forms were identified for potential inclusion in the recommended data set. Ultimately, 79 items were recommended for inclusion in minimum core data sets, including 65 items in the level 1 data set, and an additional 14 items in the more specific level 2 and 3 recommended data sets. Data elements were broadly divided into (i) patient characteristics; (ii) comorbidities; (iii) current medications; (iv) lesion treated; (v) procedure; (vi) bypass; (vii) endarterectomy (viii) catheter based intervention; (ix) complications; and (x) follow up.
Conclusion
A modified Delphi study allowed 25 international vascular registry experts to achieve a consensus recommendation for a minimum core data set and an optimum data set for peripheral arterial revascularisation registries. Continued global harmonisation of registry infrastructure and definition of items will overcome limitations related to single country investigations and enhance the development of real world evidence. Show less

Results: Out of 40 invited experts 30 joined the panel and completed round one. Twenty-four experts completed the second and final round. Forty-three indicators of outcome quality were initially identified and validated by the panel. After two Delphi rounds, 12 indicators (27.9 %) achieved the limit of agreement for relevance and four (9.3 %) for practicability. Major adverse limb events (MALE), major amputation, and major re-intervention (or re-operation) were consented as both highly relevant… Show more

Results: Out of 40 invited experts 30 joined the panel and completed round one. Twenty-four experts completed the second and final round. Forty-three indicators of outcome quality were initially identified and validated by the panel. After two Delphi rounds, 12 indicators (27.9 %) achieved the limit of agreement for relevance and four (9.3 %) for practicability. Major adverse limb events (MALE), major amputation, and major re-intervention (or re-operation) were consented as both highly relevant and practicable. Additionally, major adverse cardiovascular events (MACE), myocardial infarction, stroke or transient ischaemic attack, all-cause death, all re-intervention (or re-operation), wound infection, vascular access-related major complication, walking distance, and Rutherford-classification were consented as highly relevant. Ankle-brachial-index was consented as highly practicable.
Conclusions: This Delphi approach of vascular experts identified three indicators as highly relevant and clinically practicable to be recommended as indicators of outcome quality in invasive PAD treatment. Among others, these consented items may help in harmonising future studies and quality benchmarking increasing their comparability, validity, and efficiency. Show less

Hintergrund: Die komplexe endovaskuläre Versorgung von Aneurysmen und Dissektionen der Aorta mithilfe von fenestrierten oder gebranchten Endoprothesen (FB-EVAR) ist noch immer eine Herausforderung für die endovaskuläre Gefäßchirurgie. Bisher besteht die Evidenzbasis zu diesem Thema weitestgehend aus Single-Center-Studien, die mit einer multizentrischen Versorgungsrealität verglichen werden sollte.
Methoden: Die Daten zu stationären Behandlungen der drittgrößten gesetzlichen… Show more

Hintergrund: Die komplexe endovaskuläre Versorgung von Aneurysmen und Dissektionen der Aorta mithilfe von fenestrierten oder gebranchten Endoprothesen (FB-EVAR) ist noch immer eine Herausforderung für die endovaskuläre Gefäßchirurgie. Bisher besteht die Evidenzbasis zu diesem Thema weitestgehend aus Single-Center-Studien, die mit einer multizentrischen Versorgungsrealität verglichen werden sollte.
Methoden: Die Daten zu stationären Behandlungen der drittgrößten gesetzlichen Krankenversicherung Deutschlands, DAK-Gesundheit, wurden ausgewertet, um komplexe endovaskuläre Behandlungen der thorakalen (TA) und thorakoabdominellen inklusive der Viszeralgefäße einbeziehenden abdominellen (TAA) Aorta zu analysieren.
Ergebnisse: Zwischen Januar 2008 und April 2017 wurden insgesamt 984 Patienten (18,1 % davon weiblich) endovaskulär mithilfe von fenestrierten oder gebranchten Endoprothesen an der TA oder TAA behandelt. Patienten mit Versorgung der TA waren etwas jünger (71,7 vs. 73,2 Jahre, p < 0,001) und häufiger weiblichen Geschlechts (38,5 % vs. 17,0 %, p < 0,001) als Patienten mit Versorgung der TAA. Bei TA wurde seltener eine periphere (atherosklerotische) Gefäßerkrankung dokumentiert (67,3 % vs. 80,4 %, p = 0,036). Die Krankenhaus- (17,3 % vs. 4,6 %), 30-Tages- (26,9 % vs. 8,2 %) und 90-Tages-Sterblichkeit (34,6 % vs. 10,1 %) war signifikant höher bei Behandlung der TA im Vergleich zur TAA. Die Rate an Schlaganfällen und transienten ischämischen Attacken war höher bei Versorgung der TA (7,7 % vs. 1,2 %, p = 0,002) im Vergleich zur Versorgung der TAA.
Schlussfolgerung: In dieser großen Routinedatenanalyse zur Darstellung der multizentrischen Versorgungsrealität zeigten sich relevante Unterschiede sowohl hinsichtlich Patientenalter, Geschlecht und Sterblichkeit zwischen den analysierten Gruppen (TA vs. TAA) als auch im Vergleich mit den derzeit verfügbaren Studienergebnissen. Multizentrische validierte Registerstudien sind zu empfehlen. Show less

Verschiedene Formen von Registern gewinnen als eine Form der Big-Data-Anwendung in der Medizin in den letzten Jahren zunehmend an Bedeutung. Unter anderem aufgrund dieser Veränderungen, insbesondere im Bereich der digitalen Datenverarbeitung, findet bereits seit mehreren Jahren ein Reformprozess des EU-Datenschutzes statt. Nach einer Übergangsfrist wird eine neue Datenschutzgrundverordnung in der Europäischen Union am 25.05.2018 in Kraft treten und dann das noch bestehende… Show more

Verschiedene Formen von Registern gewinnen als eine Form der Big-Data-Anwendung in der Medizin in den letzten Jahren zunehmend an Bedeutung. Unter anderem aufgrund dieser Veränderungen, insbesondere im Bereich der digitalen Datenverarbeitung, findet bereits seit mehreren Jahren ein Reformprozess des EU-Datenschutzes statt. Nach einer Übergangsfrist wird eine neue Datenschutzgrundverordnung in der Europäischen Union am 25.05.2018 in Kraft treten und dann das noch bestehende Bundesdatenschutzgesetz ablösen. Eine gewissenhafte Beschäftigung mit dem Thema Datenschutz und die konsequente Einhaltung der gesetzlichen Rahmenbedingungen stellen eine obligatorische Voraussetzung für die erfolgreiche Durchführung von Registerprojekten in der medizinischen Forschung dar. Der technische Fortschritt und die zunehmende Menge an digital gespeicherten Daten machen belastbare technische Datenschutzlösungen erforderlich, um die Patientenrechte zu wahren. Dieser Artikel gibt einen Überblick über die Hintergründe, Entwicklungen und damit verbundene Maßnahmen im Zusammenhang mit medizinischen Registerprojekten. Show less

In der vaskulären Forschung kommen zahlreiche statistische Kennzahlen und Methoden zum Einsatz. Die Auswahl des richtigen statistischen Verfahrens hängt jeweils von dem Kontext der Studienpopulation, der Häufigkeit eines Ereignisses oder der zugrunde liegenden Verteilung ab. Da es bisher nur wenige randomisierte klinische Studien (RCTs) in der Gefäßmedizin gibt und weil insbesondere Projekte der Qualitätsentwicklung auf sogenannte Real-World-Daten angewiesen sind, werden zunehmend… Show more

In der vaskulären Forschung kommen zahlreiche statistische Kennzahlen und Methoden zum Einsatz. Die Auswahl des richtigen statistischen Verfahrens hängt jeweils von dem Kontext der Studienpopulation, der Häufigkeit eines Ereignisses oder der zugrunde liegenden Verteilung ab. Da es bisher nur wenige randomisierte klinische Studien (RCTs) in der Gefäßmedizin gibt und weil insbesondere Projekte der Qualitätsentwicklung auf sogenannte Real-World-Daten angewiesen sind, werden zunehmend nichtrandomisierte Daten aus Registern oder Routinedaten der Kostenträger verwendet, sodass geeignete statistische Verfahren zur Beurteilung der Validität dieser Datenquellen erforderlich werden. Dazu gehören die Standardkennzahlen Mittelwert, Standardabweichung, Varianz und Konfidenzintervalle, aber auch Überlebenszeitanalysen, Propensity Score Matching und Cox-Regression sowie die Darstellung der Ergebnisse in Form von Kaplan-Meier-Kurven und Forest-Plots. Diese werden in diesem Artikel erklärt und anhand von ausgewählten Publikationen aus der vaskulären Versorgungsforschung dargestellt. Die gewissenhafte Auswahl des geeigneten statistischen Verfahrens in der jeweiligen Situation und das Verstehen der Methoden und Ergebnisse in wissenschaftlichen Publikationen sind von großer Wichtigkeit für die Ableitung valider Erkenntnisse. Show less

Background
Endovascular aortic repair (EVAR) has emerged as a standard of care for abdominal aortic aneurysm (AAA) repair. However, real-world evidence to compare this technology to open aortic repair (OAR) is limited. Major gaps exist related to long-term outcomes of therapies worldwide.

Methods
Health insurance claims data of Germany's third largest insurance provider, DAK-Gesundheit, were used to determine outcomes after interventions for intact AAA (iAAA) and ruptured AAA… Show more

Background
Endovascular aortic repair (EVAR) has emerged as a standard of care for abdominal aortic aneurysm (AAA) repair. However, real-world evidence to compare this technology to open aortic repair (OAR) is limited. Major gaps exist related to long-term outcomes of therapies worldwide.

Methods
Health insurance claims data of Germany's third largest insurance provider, DAK-Gesundheit, were used to determine outcomes after interventions for intact AAA (iAAA) and ruptured AAA (rAAA). The study included patients operated on between October 2008 and April 2015.

Results
Included were 5509 patients (3627 EVAR and 1859 OAR). Median follow-up was 2.44 years (range, 0-6.46 years). The in-hospital mortality was lower after EVAR compared with OAR for both iAAA (1.2% vs 5.4%) and rAAA (26.1% vs 42%; P < .001). Postoperative length of stay and occurrence of complications were also lower after EVAR. The in-hospital mortality benefits of EVAR were most prominent in octogenarians (iAAA: EVAR, 2.2%; OAR, 18.2%; rAAA: EVAR, 34.4%; OAR, 62.3%; P < .001). However, the early survival benefit after EVAR reversed at ∼1.5 years, and Cox proportional hazard models revealed no differences in overall survival between EVAR and OAR. Landmark analysis focusing on patients surviving the procedure has shown lower survival in patients with EVAR.

Conclusions
In this largest European investigation to date using health insurance claims data, we found that in-hospital outcomes in Germany favor EVAR, which is comparable to findings reported in the United States and the United Kingdom. Trends toward lower long-term survival after EVAR after discharge are important and require future research and reflection. Show less

Zahlreiche Empfehlungen in den verfügbaren internationalen Leitlinien zur Diagnostik und Behandlung der peripheren arteriellen Verschlusskrankheit (PAVK) kommen aufgrund fehlender unabhängiger Studiendaten über den Grad von Konsensempfehlungen nicht hinaus. Aufgrund von nicht einheitlich festgelegten Qualitätsindikatoren und fehlenden validen Daten zur Versorgungsrealität ist eine Überprüfung der Leitlinienkonformität der Behandlung zudem erschwert. Dieser Artikel gibt einen kurzen Überblick… Show more

Zahlreiche Empfehlungen in den verfügbaren internationalen Leitlinien zur Diagnostik und Behandlung der peripheren arteriellen Verschlusskrankheit (PAVK) kommen aufgrund fehlender unabhängiger Studiendaten über den Grad von Konsensempfehlungen nicht hinaus. Aufgrund von nicht einheitlich festgelegten Qualitätsindikatoren und fehlenden validen Daten zur Versorgungsrealität ist eine Überprüfung der Leitlinienkonformität der Behandlung zudem erschwert. Dieser Artikel gibt einen kurzen Überblick über die verfügbaren Leitlinienempfehlungen und stellt vor diesem Kontext das mehrstufige multimethodale IDOMENEO-Projekt vor, das sich mit Primärdatenerhebungen (GermanVasc-Register) und Routinedatenerhebungen (BARMER) in der PAVK-Behandlung befasst. Show less