AAA is defined as an infrarenal aortic diameter ≥3 cm. The population prevalence of AAA in adults older than age 50 years ranges from 3.9% to 7.2% in men and from 1% to 1.3% in women.34,35 The dreaded consequence of AAA is rupture, which is often fatal—most patients die before reaching a hospital. The chances of rupture and mortality increase dramatically when the aortic diameter exceeds 5.5 cm. The strongest risk factors for AAA are older age, male sex, smoking, and family history; other potential risk factors include history of other vascular aneurysms, taller height, coronary artery disease, cerebrovascular disease, atherosclerosis, hypertension, and hyperlipidemia.

Because symptoms are uncommon and screening can reduce AAA-related mortality by about 50% over 13 to 15 years, the USPSTF makes a grade B recommendation for one-time ultrasound screening of men aged 65 to 75 years who have smoked more than 100 cigarettes in a lifetime.36 Clinicians can selectively offer screening to men in this age range who have never smoked (grade C); evidence is insufficient regarding screening women in this age range who have ever smoked (I statement). However, the USPSTF recommends against screening women who have never smoked (grade D). Ultrasound is a noninvasive, inexpensive, and accurate (sensitivity 94% to 100%; specificity 98% to 100%) screening test for diagnosing AAA. Palpation is not sensitive enough to be recommended for screening.

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