From the Guidelines
Abdominal aortic aneurysm (AAA) screening is recommended for men aged 65-75 who have ever smoked, with a one-time ultrasound, as it has been shown to reduce AAA-specific mortality 1. This screening is not routinely recommended for women or men who have never smoked unless they have risk factors such as family history of AAA. The screening is simple, non-invasive, and takes about 30 minutes to complete. If an aneurysm is detected, management depends on its size: small aneurysms (less than 5.5 cm) are typically monitored with periodic ultrasounds, while larger ones may require surgical repair. AAA screening is important because these aneurysms are often asymptomatic until they rupture, which has a high mortality rate of 80%. The rationale for targeting older male smokers is that they have the highest risk of developing AAAs, making screening most cost-effective in this population. Early detection through screening allows for monitoring or intervention before a potentially fatal rupture occurs.
Some key points to consider:
- The USPSTF recommends one-time screening for AAA by ultrasonography in men aged 65 to 75 years who have ever smoked 1.
- The screening is accurate, with 95% sensitivity and near 100% specificity 1.
- The risk of AAA increases with a history of hypertension, smoking, and a first-degree male relative with AAA 1.
- Elective repair is considered for AAAs ≥5.5 cm in diameter 1.
- Population-based ultrasound screening studies have been recommended and have proved cost-effective for male patients >65 years of age 1.
Overall, AAA screening is a crucial tool for reducing the risk of death from ruptured AAA, particularly in high-risk populations such as older male smokers.
From the Research
AAA Screening Recommendations
- The USPSTF recommends 1-time screening for AAA with ultrasonography in men aged 65 to 75 years who have ever smoked 2.
- The USPSTF recommends that clinicians selectively offer screening for AAA with ultrasonography in men aged 65 to 75 years who have never smoked rather than routinely screening all men in this group 2.
- The USPSTF recommends against routine screening for AAA with ultrasonography in women who have never smoked and have no family history of AAA 2.
AAA Screening Benefits and Harms
- The USPSTF concludes with moderate certainty that screening for AAA in men aged 65 to 75 years who have ever smoked is of moderate net benefit 2.
- The USPSTF concludes with moderate certainty that screening for AAA in men aged 65 to 75 years who have never smoked is of small net benefit 2.
- The USPSTF concludes that the evidence is insufficient to determine the net benefit of screening for AAA in women aged 65 to 75 years who have ever smoked or have a family history of AAA 2.
Statin Therapy and AAA Growth
- Some studies suggest that statins may reduce the expansion of abdominal aortic aneurysms (AAAs) independent of lipid-lowering effects 3.
- However, other studies have found no association between statin prescription or LDL concentration with AAA expansion 4.
- A systematic review of the literature found that the claim that statins attenuate AAA growth remains questionable, and further prospective studies are required to determine the effect of statin therapy on AAA growth 3.
Imaging Techniques for Atherosclerosis
- Ultrasound imaging can be used to assess the progression of atherosclerosis and evaluate cardiovascular risk 5, 6.
- The American Society of Echocardiography has formulated recommendations for the standardization of focused 2D and 3D carotid arterial plaque ultrasound image acquisition and measurement for the purpose of cardiovascular disease stratification 6.