Sibling risks of abdominal aortic aneurysm

Lancet. 1995 Sep 2;346(8975):601-4. doi: 10.1016/s0140-6736(95)91436-6.


There is evidence that the risk of abdominal aortic aneurysm (AAA) is greater in first-degree relatives of patients with the disorder than in the same age group of the general population. We conducted a 3-year study of siblings of AAA probands and siblings of a control group (cataract surgery patients) of the same age. Genetic information was obtained by interview from 126 probands and 100 controls; another family member was present at the interview. Medical records were obtained and further information verified before a sibling (over age 50) was assigned affected status. Of 427 siblings of probands, 19 (4.4%) had probable or definite AAA, compared with five (1.1%) of 451 siblings of controls. The lifetime cumulative risks of AAA at age 83 were 11.7% (SD 3.1) and 7.5% (4.1), respectively. The risk of AAA began at an earlier age and increased more rapidly for probands' siblings than for controls' siblings (p < 0.01, log-rank test). A risk comparison, based on the results of ultrasound screening of 54 geographically accessible siblings of probands and the 100 controls showed a similar pattern. Ten (19%) siblings of probands and eight (8%) controls had AAA on ultrasound (lifetime cumulative risk 60.8% [18.9] vs 14.9% [5.1], p = 0.01). These results show that familial factors influence the age of onset of AAA. We recommend routine ultrasound examination of siblings of patients with AAA.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Age Factors
  • Aged
  • Aged, 80 and over
  • Aortic Aneurysm, Abdominal / diagnostic imaging
  • Aortic Aneurysm, Abdominal / genetics*
  • Case-Control Studies
  • Female
  • Humans
  • Male
  • Middle Aged
  • Nuclear Family*
  • Risk Factors
  • Sex Factors
  • Ultrasonography