Abdominal Aortic Aneurysm (Aaa): Cost-Effectiveness of Screening, Surveillance of Intermediate-Sized Aaa, and Management of Symptomatic Aaa

Abstract

Physicians must make decisions about screening patients for abdominal aortic aneurysms (AAAs), monitoring or referring for surgery patients with AAAs of various sizes, and assessing patients with symptoms that may be related to AAAs. This review article analyzes the evidence for each scenario. The effectiveness and cost-effectiveness of screening for AAA is based on results from four randomized controlled trials. A cost-effectiveness analysis using a Markov model showed that ultrasound screening of white men beginning at age 65 is both effective and cost-effective in preventing AAA-related death. Such screening would have a small but real impact over a 20-year period in these men. For patients with a known AAA-which is often detected incidentally-the evidence clearly suggests periodic ultrasound surveillance for those with small AAAs (3.0-3.9 cm in diameter) and elective surgical repair for those with large AAAs (>or=5.5 cm). Two recent randomized controlled trials have shown that early surgical repair confers no survival benefit compared with periodic surveillance for patients with intermediate-sized AAAs (4.0-5.5 cm in diameter), so those patients can also be monitored. Some centers choose to increase the frequency of monitoring to every 3 to 6 months when the AAA reaches 5.0 cm. Factors to consider in assessing symptomatic patients include the high risk of life-threatening conditions, the potential increased risk of death or poor outcome with delay in diagnosis, the limitations of ultrasound in identifying whether symptoms are due to known or suspected AAA, and the timely availability of computed tomography or other imaging tests. If available, computed tomography is preferred in patients with recent or severe symptoms, since it is better at detecting retroperitoneal hemorrhage and other complications and in providing preoperative definition of the anatomy.

Intracranial and Abdominal Aortic Aneurysms: Similarities, Differences, and Need for a New Class of Computational Models

“…AAAs are typically defined by a 1.5 or more fold increase in diameter or simply a diameter greater than 3 cm; they tend to be diffuse, involving up to 9 cm of the infrarenal aorta ( Figure 2). These lesions are six times more common in men, but three times more likely to rupture in women (57). Overall, AAAs affect 6 to 9% of people in the Industrialized World aged 65 and older.…”

Analysis of risk factors for abdominal aortic aneurysm in a cohort of more than 3 million individuals

“…4 AAAs can be detected noninvasively and relatively inexpensively through ultrasound imaging, which has a sensitivity and specificity of nearly 100% for this disorder. 5 Early detection of AAA can be life-saving, giving patients the opportunity to undergo elective surgical repair, a much safer and effective intervention than emergency repair after rupture. The United States Preventive Services Task Force (USPSTF) has recommended AAA screening for men aged 65 to 75 years with a history of smoking 6 because of the high prevalence of AAA in this population and the demonstrated reduction in AAA-related mortality among those who have been screened.…”

Analysis of cost effectiveness of screening Danish men aged 65 for abdominal aortic aneurysm

“…3 Our estimate is not comparable with previous modelling studies, which in general claim that screening for abdominal aortic aneurysm is cost effective. [4][5][6][7][8][9][10][11][12] We believe our study provides a more realistic estimate of cost effectiveness. For instance, previous studies did not use enhanced Markov models with time dependency built into the transitional probabilities, nor could they provide solid evidence of model validity.…”

“…[4][5][6][7][8][9][10][11][12] Inconsistencies in the inputs, structure, and results of the model, together with optimistic assumptions about mortality and quality of life after elective surgery, and a focus on short term clinical costs, have made the relevance of these models for decision making unclear. Accordingly, new research on cost effectiveness of screening is recommended.…”