@article{5a9facdda2554cc6ba395611dbbdba2b,
title = "Patients with a Ruptured Abdominal Aortic Aneurysm Are Better Informed in Hospitals with an “EVAR-preferred” Strategy: An Instrumental Variable Analysis of the Dutch Surgical Aneurysm Audit",
abstract = "Background: While several observational studies suggested a lower postoperative mortality after minimal invasive endovascular aneurysm repair (EVAR) in patients with a ruptured abdominal aortic aneurysm (RAAA) compared to conventional open surgical repair (OSR), landmark randomized controlled trials have not been able to prove the superiority of EVAR over OSR. Randomized controlled trials contain a selected, homogeneous population, influencing external validity. Observational studies are biased and adjustment of confounders can be incomplete. Instrumental variable (IV) analysis (pseudorandomization) may help to answer the question if patients with an RAAA have lower postoperative mortality when undergoing EVAR compared to OSR.Methods: This is an observational study including all patients with an RAAA, registered in the Dutch Surgical Aneurysm Audit between 2013 and 2017. The risk difference (RD) in postoperative mortality (30 days/in-hospital) between patients undergoing EVAR and OSR was estimated, in which adjustment for confounding was performed in 3 ways: linear model adjusted for observed confounders, propensity score model (multivariable logistic regression analysis), and IV analysis (two-stage least square regression), adjusting for observed and unobserved confounders, with the variation in percentage of EVAR per hospital as the IV instrument.Results: 2419 patients with an RAAA (1489 OSR and 930 EVAR) were included. Unadjusted postoperative mortality was 34.9% after OSR and 22.6% after EVAR (RD 12.3%, 95% CI 8.5–16%). The RD adjusted for observed confounders using linear regression analysis and propensity score analysis was, respectively, 12.3% (95% CI 9.6–16.7%) and 13.2% (95%CI 9.3–17.1%) in favor of EVAR. Using IV analysis, adjusting for observed and unobserved confounders, RD was 8.9% (95% CI -1.1–18.9%) in favor of EVAR.Conclusions: Adjusting for observed confounders, patients with an RAAA undergoing EVAR had a significant better survival than OSR in a consecutive large cohort. Adjustment for unobserved confounders resulted in a clinical relevant RD. An “EVAR preference strategy” in patients with an RAAA could result in lower postoperative mortality.",
author = "{In collaboration with the Dutch Society for Vascular Surgery, the Steering Committee of the Dutch Surgical Aneurysm Audit and the Dutch Institute for Clinical Auditing} and {Van den Akker}, {P. J.} and Arts, {C. H.} and Bakker, {O. J.} and {van den Berg}, M. and P. Berger and Bleker, {R. J.} and Blok, {J. J.} and Bodegom, {M. E.} and J. Bosma and Bouwman, {L. H.} and {de Bruijn}, {M. T.} and {de Bruin}, {J. L.} and Buijs, {M. A.} and Dijkstra, {M. L.} and {van Doorn}, {R. C.} and Elshof, {J. W.} and {van Engeland}, {M. I.} and Faber, {M. J.} and Fokkema, {T. M.} and Fritschy, {W. M.} and {de Groot}, {H. G.} and {de Haan}, {E. F.} and Helleman, {J. N.} and Hendriks, {J. M.} and Hollander, {E. J.} and M. Hommes and Huisman, {L. C.} and Jacobs, {M. J.} and Janssen, {R. J.} and Jiang, {H. H.} and {de Jong}, {S. C.} and {Khodadade Jahrome}, A. and Kolkert, {J. L.} and Koning, {G. G.} and R. Konings and Krol, {R. M.} and Kruse, {R. R.} and {van der Laan}, L. and {van der Laan}, {M. J.} and Lind, {R. C.} and {Liqui Lung}, {P. F.} and Loos, {M. J.} and {von Meijenfeldt}, {G. C.} and Menting, {T. P.} and W. Mulder and Nederhoed, {J. H.} and Nieuwenhuis, {D. H.} and Petri, {B. J.} and Pol, {R. A.} and {de Ridder}, {J. A.} and {van Rijn}, {M. J.} and Saleem, {B. R.} and Salemans, {P. B.} and {van Schaik}, J. and {van Schaik}, {P. M.} and Scheltinga, {M. R.} and Smeets, {H. J.} and L. Smeets and Smeets, {R. R.} and {de Smet}, {A. A.} and Smit, {P. C.} and Smits, {T. M.} and Speijers, {M. J.} and Tielliu, {I. F.} and Veen, {E. J.} and Veldman, {M. G.} and Verhoeven, {B. A.} and Vermeulen, {C. F.} and Vermeulen, {E. G.} and Vierhout, {B. P.} and Visser, {M. J.} and Vos, {A. W.} and {de Vos}, B. and Vos, {C. G.} and Vos, {G. A.} and {de Vries}, {A. C.} and {de Vries}, {D. K.} and {de Vries}, {J. P.} and {de Vries}, M. and {van Walraven}, {L. A.} and Wever, {J. J.} and Wiersema, {A. M.} and Willems, {M. C.} and Witte, {M. E.} and Wong, {C. Y.} and Zeebregts, {C. J.} and Karthaus, {Eleonora G.} and Niki Lijftogt and Anco Vahl and {Van Der Willik}, {Esmee M.} and Sonia Amodio and {Van Zwet}, {Erik W.} and Hamming, {Jaap F.}",
note = "Funding Information: The authors would like to thank all surgeons, registrars, physician assistants, and administrative nurses who registered all patients in the DSAA and in the Dutch Surgical Aneurysm Audit group. Funding: This research received no specific funding. Publisher Copyright: {\textcopyright} 2020 Elsevier Inc.",
year = "2020",
month = nov,
doi = "10.1016/j.avsg.2020.06.015",
language = "English",
volume = "69",
pages = "332--344",
journal = "Annals of vascular surgery",
issn = "0890-5096",
publisher = "ELSEVIER SCIENCE INC",
}