Clinicians should offer one-time screening with ultrasonography for abdominal aortic aneurysm (AAA) in men aged 65 to 75 years who are past or current smokers, and should selectively offer screening to men in that age group who have never smoked.
These recommendations are part of updated guidelines issued by the U.S. Preventive Services Task Force (USPSTF; guidelines available at www.uspreventiveservicestaskforce.org/uspstf/uspsaneu.htm).
The USPSTF document noted that population-based studies of adults older than age 50 years have found that the prevalence of AAA is 3.9% to 7.2% in men and 1.0% to 1.3% in women. Many AAAs, typically identified by an aortic diameter of 3.0 cm or larger, are asymptomatic until rupture, at which point they are usually sudden and frequently fatal.
Risk factors for AAA include advanced age, male gender, smoking, and a first-degree family history of AAA requiring surgical repair. According to the USPSTF recommendations, evidence indicates only a small net benefit of screening all men aged 65 to 75 years who have never smoked. Therefore, the decision to screen such men should be made based on the individual’s medical and family history, other risk factors, and personal values.
The task force also noted only a minor health benefit in additional screening for those who had a normal aortic diameter on first screening.
The USPSTF recommends against routine screening for AAA in women who have never smoked, and found inadequate evidence to recommend for or against screening in women aged 65 to 75 years who are past or current smokers.
In the trials evaluated by the USPSTF in formulating these recommendations, conventional abdominal duplex ultrasonography was the primary method used for AAA screening. However, noted the guideline authors, several small, observational studies suggest that handheld ultrasonography done in clinician office settings may be reasonable.