Abdominal Aortic Aneurysm Screening Practices: Impact of the 2014 U.S. Preventive Services Task Force Recommendations

To assess changes in abdominal aortic aneurysm (AAA) ultrasound screening associated with the release of revised U.S. Preventive Services Task Force (USPSTF) recommendations on June 24, 2014.

All AAA screening ultrasound examinations performed in the Massachusetts General Hospital radiology department in the 15 months before and after the new guidelines were retrospectively reviewed to assess changes in examination volume and appropriateness, demographics, aneurysm detection rate and size at diagnosis, frequency and type of incidental findings, and radiologist recommendations. Examinations were considered "definitely appropriate" if meeting USPSTF grade "B" evidence and "possibly appropriate" if meeting grade "C" or "I" evidence, based on available guidelines. Means were compared with the t test.

A total of 831 examinations were reviewed, 417 (50.2%) performed before and 414 (49.8%) after the new guidelines, with overall mean (SD) subject age 67.9 (6.8) years, 89.2% male. Appropriate examinations increased from 289 of 417 (69.3%) to 313 of 414 (75.6%) after the new guidelines (P = .04), mostly due to definitely appropriate examinations (253/417 [60.7%] versus 286/414 [69.1%], P = .01). Aneurysm detection rates increased from 23 of 417 (5.5%) to 39 of 414 (9.4%), P = .03. Mean (SD) aneurysm size (cm) at diagnosis decreased from 3.8 (0.7) to 3.3 (0.6), P = .01. Examination volume, demographics, and rates of incidentals and recommendations remained similar. Incidentals arose in 15.4% of all examinations, often iliac artery aneurysms or renal masses. Recommendations were made in 5.1%, mostly for cross-sectional imaging.

The revised USPSTF guidelines have been associated with increased AAA screening appropriateness and aneurysm detection in our practice, with smaller aneurysm size at diagnosis.