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Background: The aim was to assess the relationship between hospital volume and outcome after abdominal aortic aneurysm (AAA) surgery in the UK. Methods: Hospital Episode Statistics (2000-2005) were classified as elective, urgent or ruptured AAA repair. Analysis was by modelling of mortality rate, complication rate and length of hospital stay with regard to the annual operative volume, after risk adjustment. Results: There were 112 545 diagnoses, or repairs, of AAAs, of which 26 822 were infrarenal aneurysms. The mean mortality rate was 7.4, 23.6 and 41-8 per cent for elective, urgent and ruptured AAA repair respectively. Elective AAA repair undertaken at high-volume hospitals showed volume-related improvements in mortality (P < 0.001). Patients were discharged from hospital earlier (P < 0.001). The critical volume threshold was 32 elective AAA repairs per year. For urgent repair, patients at high-volume hospitals had a reduced mortality rate (P = 0.017) with an increased length of stay (P = 0.041). There was no relationship between volume and outcome for ruptured AAA repairs. Conclusion: Increased annual volumes were associated with significant reductions in mortality for elective and urgent AAA repair, but not for repair of ruptured AAAs. [ABSTRACT FROM AUTHOR]

Background: This study investigated the volume-outcome relationship for abdominal aortic aneurysm (AAA) surgery and quantified critical volume thresholds. Methods: PubMed, EMBASE and the Cochrane library were searched for articles on the operation volume-outcome relationship in elective and ruptured AAA surgery. UK Hospital Episode Statistics data were also considered. Elective and ruptured AAA repairs were dealt with separately. The data were meta-analysed, and the odds ratios (95 per cent confidence interval) for mortality at higher- and lower-volume hospitals were compared. Volume thresholds were identified from each paper. Results: The analysis included 421 299 elective and 45 796 ruptured AAA operations. Significant relationships between mortality and annual volume were noted for both groups. Overall, the weighted odds ratio was 0.66 (0.65 to 0.67) for elective repair at a threshold of 43 AAAs per annum and (0.73 to 0.82) for ruptured aneurysm repair at a threshold of 15 AAAs per annum, both in favour of high-volume institutions. Conclusion: Higher annual operation volumes are associated with significantly lower mortality in both elective and ruptured AAA repair. This suggests that AAA surgery should be performed only at higher-volume centres. [ABSTRACT FROM AUTHOR]

BACKGROUND Studies with short-term follow-up have shown that screening for abdominal aortic aneurysm (AAA) is cost-effective and reduces mortality. OBJECTIVE To evaluate the long-term cost-effectiveness and mortality benefit of screening for AAA. DESIGN AND INTERVENTION The Multicentre Aneurysm Screening Study (MASS) was a randomized trial conducted at four centers in the UK between 1997 and 1999. Men aged 65-74 years, identified through family physician records, were eligible for inclusion in the study. Individuals with a terminal illness, previous AAA surgery, or a known AAA, were excluded. Participants were randomly assigned to receive an invitation to AAA ultra-sonography screening or to not receive an invitation. Men with an aortic diameter greater than 3.0cm were classified as having an AAA. Invitations to yearly screening were issued to those with an aortic diameter of 3.0-4.4cm. Screening every 3 months was recommended for those with an aortic diameter of 4.5-5.4 cm. Individuals with signs or symptoms of AAA, an aortic diameter exceeding 5.5cm, or aortic expansion of 1.0cm or more within a year, were eligible for surgery. Rescreening was not offered to participants with an aortic diameter of less than 3.0cm. Patients were followed up through hospital records and the UK Office of National Statistics. The 4-year outcomes of this study have previously been reported. OUTCOME MEASURES The primary end point was AAA-related death. All-cause mortality and cost-effectiveness were also assessed. RESULTS After exclusions, a total of 67,770 men were randomized; 33,883 were assigned to receive invitations to screening and the remaining 33,887 formed the control group. The mean age of participants was 69.2 years for both groups. Screening attendance was high in the invited group (27,204 attended; 80%) and 1,334 men were identified as having an AAA. After 7 years, there had been 14,001 all-cause deaths, of which 301 were AAA-related. In addition, 24% of all participants did not attend recall scans and were, therefore, lost to clinical follow-up. Compared with the control group, the hazard ratio for AAA-related mortality at 7 years in the patients invited for screening was 0.53 (95% CI 0.42-0.68) and 0.96 (95% CI 0.93-1.00) for all-cause mortality. The rate of AAA rupture in men who had an aortic diameter of less than 3.0cm was low at approximately 0.54 ruptures per 100,000 person years. The cost-effectiveness at 7 years was estimated to be US$19,500 (95% CI $12,400-$39,800) per life-year gained for AAA-related mortality and $7,600 (95% CI $3,300-$00 per life-year gained for all-cause mortality. CONCLUSION AAA screening of men aged 65-74 years is cost-effective and is associated with approximately a 50% reduction in AAA-related mortality. [ABSTRACT FROM AUTHOR]