Two new studies suggest that screening offers long-term benefits, but the picture is not so clear for endovascular repair.
Guidelines from the U.S. Preventive Services Task Force recommend that men aged 65 to 74 who have ever smoked be screened with abdominal ultrasonography for abdominal aortic aneurysm (AAA; Journal Watch Feb 18 2005). But questions remain regarding the long-term benefits of screening and surgical options.
In a population-based U.K. trial, 67,770 men were randomized to receive or not receive an invitation for ultrasonographic screening for AAA. Men with aortic diameters of 3.0 cm or greater on screening were monitored; surgery was considered in those with diameters of 5.5 cm, expansion of 1.0 cm in a year, or symptoms. Previous findings showed that screening decreased AAA-related mortality during an average follow-up of 4 years (Journal Watch Jan 3 2003). Now, new results indicate that at about 7 years, men invited to receive screening still had lower AAA-related mortality (hazard ratio, 0.53); all-cause mortality did not differ between groups. Estimated cost was US$19,500 per year of life gained.
In a systematic review of seven randomized trials, researchers analyzed the effectiveness of different approaches to unruptured AAA. Two trials compared open repair to surveillance of small AAA (<5.5 cm) and found no significant difference in all-cause or AAA-related mortality. Three trials compared endovascular repair with open repair of large AAA: Endovascular repair was associated with lower 30-day mortality (relative risk, 0.33), and with lower AAA-related mortality (RR, 0.53) but not all-cause mortality (RR, 0.95) during up to 4 years of follow-up; it was also associated with shorter hospital stays but higher rates of reintervention. In one trial, endovascular repair did not decrease mortality among those deemed unfit for open repair.
Comment: Screening for abdominal aortic aneurysm appears to have long-term benefits and to be cost-effective. Endovascular repair appears to compare favorably with open repair but requires more reinterventions during follow-up.
— Richard Saitz, MD, MPH, FACP, FASAM
Published in Journal Watch General Medicine June 7, 2007
Kim LG et al. A sustained mortality benefit from screening for abdominal aortic aneurysm. Ann Intern Med 2007 May 15; 146:699-706.