Purpose: Studies have shown that 11% to 18%;, of patients with an abdominal aortic aneurysm (AAA) have a first-degree relative with an AAA. A familial pattern among patients with peripheral arterial aneurysms and arteriomegaly has not been reported. The objective of this study was to examine familial patterns among patients with peripheral arterial aneurysm and arteriomegaly and compare them with patterns among patients with AAA. Methods Pedigrees were constructed for first-degree relatives of patients a ho received the diagnosis of peripheral arterial aneurysm, arteriomegaly, or AAA from 1988 through 1996. The presence of aneurysms and risk factors was confirmed for patients and relatives by means of telephone interviews and review of hospital and physician records. Results: Seven hundred three first-degree relatives older than 50 years were contacted for 140 probands with peripheral arterial aneurysm, AAA, or arteriomegaly. There were differences in risk factors for hernia and diabetes mellitus among the probands with peripheral arterial aneurysm, AAA, or arteriomegaly but none for relatives. Patients with peripheral arterial aneurysm (n = 40) had a 10% (4/40) familial incidence rate of an aneurysm, patients with AAA (n = 86) had a 22% (19/86) familial incidence rate, and patients with arteriomegaly (n = 14) had a 36% (5/14) familial incidence rate. AAA (24/28, or 86%) was the aneurysm diagnosed most commonly among first-degree relatives. Most aneurysms (85%) occurred among men. Conclusion: There appears to be a gradation of familial patterns from peripheral arterial aneurysm to AAA to arteriomegaly among patients with degenerative aneurysmal disease, and there appears to be a predominance among men. Relatives of patients with any of the 3 lesions-peripheral arterial aneurysm, AAA, arteriomegaly-most frequently have AAA. Relatives of patients with AAA, peripheral arterial aneurysm, or arteriomegaly map be screened by means of a physical examination for peripheral aneurysmal disease. Screening by means of ultrasound examination of the aorta should be limited to first-degree relatives of patients with aortic aneurysms or arteriomegaly.
