Regional Differences in Case Mix and Peri-operative Outcome After Elective Abdominal Aortic Aneurysm Repair in the Vascunet Database.
OBJECTIVE
National differences exist in the outcome of elective abdominal aortic aneurysm (AAA) repair. The role of case mix variation was assessed based on an international vascular registry collaboration.


METHODS
All elective AAA repairs with aneurysm size data in the Vascunet database in the period 2005-09 were included. AAA size and peri-operative outcome (crude and age adjusted mortality) were analysed overall and in risk cohorts, as well as per country. Glasgow Aneurysm Score (GAS) was calculated as risk score, and patients were stratified in three equal sized risk cohorts based on GAS. Predictors of peri-operative mortality were analysed with multiple regression. Missing data were handled with multiple imputation.


RESULTS
Patients from Australia, Finland, Hungary, Norway, Sweden and the UK (n = 5,895) were analysed; mean age was 72.7 years and 54% had endovascular repair (EVAR). There were significant variations in GAS (lowest = Finland [75.7], highest = UK [79.4], p for comparison of all regions < .001), proportion of AAA < 5.5 cm (lowest = UK [6.4%], highest = Hungary [29.0%]; p < .001), proportion undergoing EVAR (lowest = Finland [10.1%], highest = Australia [58.9%]; p < .001), crude mortality (lowest = Norway [2.0%], highest = Finland [5.0%]; p = .006), and age adjusted mortality (lowest = Norway [2.5%], highest = Finland [6.0%]; p = .048). Both aneurysm size and peri-operative mortality were highest among patients with a GAS >82. Of those with a GAS >82, 8.4% of men and 20.8% of women had an AAA <5.5 cm.


CONCLUSIONS
Important regional differences exist in case selection for elective AAA repair, including variations in AAA size and patient risk profile. These differences partly explain the variations in peri-operative mortality. Further audit is warranted to assess the underlying reasons for the regional variation in case-mix.
Department of Surgical Sciences, Vascular Surgery, Uppsala University, Uppsala, Sweden. Electronic address: kevin.mani@surgsci.uu.se.
K
K
Mani
Department of Vascular Surgery, Helsinki University Hospital, Helsinki, Finland.
M
M
Venermo
Australian and New Zealand Society for Vascular Surgery, East Melbourne, Australia.
B
B
Beiles
Department of Vascular Surgery, University Medical School, Pecs, Hungary.
G
G
Menyhei
Department of Vascular Surgery, St Olavs Hospital, Trondheim, Norway.
M
M
Altreuther
St George's Vascular Institute, St George's Hospital, London, UK.
I
I
Loftus
Department of Surgical Sciences, Vascular Surgery, Uppsala University, Uppsala, Sweden.
M
M
Björck
D000368:Aged; D000369:Aged, 80 and over; D017544:Aortic Aneurysm, Abdominal / Q000175:diagnosis / Q000401:mortality / Q000601:surgery*; D001315:Australia; D016208:Databases, Factual; D017558:Elective Surgical Procedures; D057510:Endovascular Procedures / Q000009:adverse effects / Q000401:mortality; D005060:Europe; D005260:Female; D054625:Healthcare Disparities; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D016017:Odds Ratio; D012042:Registries; D018570:Risk Assessment; D012307:Risk Factors; D013997:Time Factors; D016896:Treatment Outcome; D014656:Vascular Surgical Procedures / Q000009:adverse effects / Q000401:mortality
Abdominal aortic aneurysm; Case mix; Outcome; Regional differences