Abdominal aortic aneurysm(AAA) occurs when the infrarenal aorta expands to a maximal diameter of 3.0cm or greater. Although AAA may asymptomatic for many years, almost one third eventually rupture if left untreated.

Several randomized trials showed that ultrasonographic screening for AAA could reduce the frequency of acute operations and AAA-related mortality.

However, all of randomized trials were performed in Western countries. There was no randomized trials for AAA screening in Asian countries.

This randomized, controlled trial is to analyze the benefits of screening old population for AAA in Korea.

Old population, aged from 60 to 85 years, are randomized into two groups; one group is invited for ultrasonographic screening for AAA, and the other acts as age- and sex-matched controls.

For screening group, The anterioposterior and transverse diameter of the infrarenal aorta is measured at their maximal sizes. The subsequent surveillance of screened patients is done as follows

• Aortic diameter less than 3.0cm, no further testing
• AAA 3 to 4cm, ultrasonographic follow-up every year
• AAA 4 to 5cm, ultrasonographic follow-up every 6 months
• AAA greater than 5cm, referral to a vascular surgeon

For control group, the information for any causes of death is collected every year.

Inclusion Criteria:

• all men aged 60 to 85 years
• women aged 60 to 85 years with cardiovascular risk factors such as hypertension, hyperlipidemia, peripheral arterial occlusive disease, coronary artery disease, cerebrovascular attack.
• men and women older than 50 years with a family history of AAA

Exclusion Criteria:

• people who was diagnosed with AAA
• people who underwent aneurysm repair such as open aneurysm repair or endovascular aneurysm repair
• People who underwent abdominal aortic surgery such as aortobifemoral bypass
• People whose life expectancy is less than 2 years
• People who appear unfit for repair of AAA
• people who do not agree with this study

Popultaion who reside in Korea as an Asian