USPSTF review finds benefits with AAA screening

An updated review for the U.S. Preventive Service Task Force (USPSTF) found evidence in favor of ultrasonography screening for abdominal aortic aneurysm (AAA) in elderly men. A review of four randomized clinical trials showed reduced rupture rates and mortality benefits with screening.

The review, led by Janelle M. Guirguis-Blake, MD, of the University of Washington in Tacoma, was designed to update a 2005 USPSTF analysis by adding new trials along with the previously reviewed literature. The results were published in the March 4 issue of the Annals of Internal Medicine.

Guirguis-Blake et al searched MEDLINE from January 2004 through September 2013 and the Database of Abstracts of Reviews of Effects and the Cochrane Central Register of Controlled Trials from January 2004 through January 2013 for English language studies that assessed the benefit of AAA ultrasonography screening in asymptomatic populations.

They identified four clinical trials with a total of 137,214 participants that evaluated the efficacy of AAA screening in population-based settings. The primary outcome was AAA-specific mortality, which they defined as all AAA deaths and all deaths within 30 days of AAA surgical repair. The trials also included findings on AAA rupture and all-cause mortality rates.

They determined that a one-time invitation for screening in men 65 years old and older reduced AAA rupture and AAA-related deaths but did not have a statistically significant effect on all-cause mortality. Screening was associated with more elective surgeries and fewer emergency surgeries as well as lower 30-day operative mortality rates.    

“Our systematic review of 4 population-based screening trials found convincing direct evidence that screening men aged 65 years or older decreased AAA-related mortality rates by approximately 50% over 13 to 15 years,” they wrote. “Abdominal aortic aneurysm–related mortality benefits occurred relatively early (by roughly 4 years) and were maintained for at least another decade.”

They added that identifying effective and efficient approaches for population-based AAA screening remained an issue. As the overall prevalence of AAA declines, policy makers also will need to weigh the benefit and risk of mass vs. targeted screening approaches.