What type of screening is recommended for someone with a family history of aneurysms, specifically abdominal aortic aneurysms (AAA)?

Screening for Individuals with Family History of Abdominal Aortic Aneurysms

For individuals with a first-degree family history of AAA, perform one-time ultrasound screening starting at age 50 years, regardless of sex or smoking status. 1

Screening Modality

• Abdominal ultrasonography is the gold standard screening method, offering 95% sensitivity and near 100% specificity, with no radiation exposure and excellent cost-effectiveness. 2, 3
• The ultrasound must be performed in an accredited facility with credentialed technologists to ensure quality assurance and accurate measurements. 3

Age to Begin Screening with Family History

• The Society for Vascular Surgery and Society for Vascular Medicine and Biology recommend screening men and women age 50 years and older with a family history of AAA. 1
• This is earlier than standard population-based screening (which begins at age 65-75) because family history significantly increases risk. 1
• First-degree relatives (parents, siblings, children) of AAA patients have a substantially elevated prevalence of occult AAA, with studies showing 25% of male siblings age 55+ and 6.9% of female siblings age 55+ having undiagnosed AAA. 4

What Constitutes Positive Family History

• A first-degree relative (parent, sibling, or child) with AAA, particularly one requiring surgical repair, warrants screening consideration. 2, 3
• The presence of family history can convert a "simplex" family (single affected member) to a "multiplex" family (multiple affected members), with screening revealing previously undiagnosed AAAs in up to 27.9% of families initially thought to have only one affected member. 4

Management Based on Screening Results

Normal Aorta (< 3.0 cm)

• No further testing is required after a negative initial ultrasound, as the incidence of new AAAs over 10 years ranges from only 0-4%, and death from AAA rupture after a negative ultrasound at age 65 is rare. 1, 2

Small AAA (3.0-3.9 cm)

• Yearly ultrasonographic surveillance is recommended. 1
• No immediate intervention is needed. 3

Intermediate AAA (4.0-4.4 cm)

• Ultrasound surveillance every 6 months is recommended. 1
• Surveillance is preferred over immediate surgery, as randomized trials show no mortality benefit from immediate repair compared to surveillance. 3

Large AAA (≥ 4.5 cm)

• Referral to a vascular specialist is indicated. 1
• Surgical intervention is generally recommended for AAAs ≥5.5 cm in men or ≥5.0 cm in women. 3

Important Caveats

• Age 75 years is generally considered an upper limit for screening because comorbid conditions decrease the likelihood of benefit from subsequent surgery. 2
• The highest yield for screening family members occurs in siblings age 55 years or older, where all newly diagnosed AAAs were found in one study, with no AAAs detected in relatives under age 55 or in children ages 50-59. 4
• Quality control is critical for ultrasound accuracy—absence of quality assurance measures lowers test accuracy, emphasizing the need for accredited facilities. 2
• While standard population screening focuses primarily on male smokers ages 65-75, family history supersedes these typical criteria and justifies earlier and broader screening. 1