Final 12-year follow-up of surgery versus surveillance in the UK small aneurysm trial

Background: The aim was to determine whether early open surgical repair would benefit patients with small abdominal aortic aneurysm compared with surveillance on long-term follow-up. Methods: The 1090 patients who were enrolled into the UK Small Aneurysm Trial between 1991 and 1995 were followed up for aneurysm repair and mortality until November 2005. Results: By November 2005, 714 patients (65.5 per cent) had died, 929 (85.2 per cent) had undergone aneurysm repair, 150 (13.8 per cent) had died without aneurysm repair and 11 (1.0 per cent) remained alive without aneurysm repair. After 12 years, mortality in the surgery and surveillance groups was 63.9 and 67.3 percent respectively, unadjusted hazard ratio 0.90 (P=0.139). Three-quarters of the surveillance group eventually had aneurysm repair, with a 30-day elective mortality of 6.3 per cent (versus 5.0 per cent in the early surgery group, P=0.366). Estimates suggested that the cost of treatment was 17 per cent higher in the early surgery group, with a mean difference of 1326 pound. The death rate in these patients was about twice that in the population matched for age and sex. Conclusion: There was no long-term survival benefit of early elective open repair of small abdominal aortic aneurysms. Even after successful aneurysm repair, the mortality among these patients was higher than in the general population.