Screening for Abdominal Aortic Aneurysm: A Best-Evidence Systematic Review for the U.S. Preventive Services Task Force

Abstract

While the prognosis for abdominal aortic aneurysm (AAA) rupture is poor, ultrasound imaging is an accurate and reliable test for detecting AAAs before rupture. To examine the benefits and harms of population-based AAA screening. MEDLINE (1994 to July 2004) supplemented by the Cochrane Library, a reference list of retrieved articles, and expert suggestions. Randomized trials of AAA population screening, population studies of AAA risk factors, and data on adverse screening and treatment events from randomized trials and cohort studies. All studies were reviewed, abstracted, and rated for quality by using predefined criteria. The authors identified 4 population-based randomized, controlled trials of AAA screening in men 65 years of age and older. On the basis of meta-analysis, an invitation to attend screening was associated with a significant reduction in AAA-related mortality (odds ratio, 0.57 [95% CI, 0.45 to 0.74]). A meta-analysis of 3 trials revealed no significant difference in all-cause mortality (odds ratio, 0.98 [CI, 0.95 to 1.02]). No significant reduction in AAA-related mortality was found in 1 study of AAA screening in women. Screening does not appear to be associated with significant physical or psychological harms. Major treatment harms include an operative mortality rate of 2% to 6% and significant risk for major complications. The population screening studies focused on men and provided no information on racial or ethnic groups. No information was available on uninvited control group characteristics, so the importance of risk factors such as tobacco use or family history could not be assessed. Since all trials were conducted in countries other than the United States, generalizability to the U.S. population is uncertain. For men age 65 to 75 years, an invitation to attend AAA screening reduces AAA-related mortality.