Family members of patients with abdominal aortic aneurysms are at increased risk for aneurysms: analysis of 618 probands and their families from the Liège AAA Family Study

Abstract

Background: The objectives were to answer the following questions with the help of a well-characterized population in Liège, Belgium: 1) what percentage of patients with abdominal aortic aneurysm (AAA) have a positive family history for AAA? 2) what is the prevalence of AAAs among relatives of patients with AAA? and 3) do familial and sporadic AAA cases differ in clinical characteristics?

Methods: Patients with unrelated AAA diagnosed at the Cardiovascular Surgery Department, University Hospital of Liège, Belgium, between 1999 and 2012 were invited to the study. A detailed family history was obtained in interviews and recorded using Progeny software. We divided the 618 patients into 2 study groups: group I, 296 patients with AAA (268; 91% men) were followed up with computerized tomography combined with positron emission tomography; and group II, 322 patients with AAA (295; 92% men) whose families were invited to ultrasonographic screening.

Results: In the initial interview, 62 (10%) of the 618 patients with AAA reported a positive family history for AAA. Ultrasonographic screening identified 24 new AAAs among 186 relatives (≥50 years) of 144 families yielding a prevalence of 13%. The highest prevalence (25%) was found among brothers. By combining the number of AAAs found by ultrasonographic screening with those diagnosed previously the observed lifetime prevalence of AAA was estimated to be 32% in brothers. The familial AAA cases were more likely to have a ruptured AAA than the sporadic cases (8% vs. 2.4%; P < 0.0001).

Conclusions: The findings confirm previously found high prevalence of AAA among brothers, support genetic contribution to AAA pathogenesis, and provide rationale for targeted screening of relatives of patients with AAA.

Figure 1

Outline of the Liège AAA Family Study with 618 Probands. The objectives of the study were to determine 1) what percentage of AAA patients (referred here as “AAA probands”) have a positive family history for AAA, 2) what is the prevalence of AAAs among relatives of AAA probands, and 3) whether familial AAA (FAAA) cases differ from non-familial (sporadic) AAA cases in clinical characteristics, using a well-characterized population in Liège, Belgium. US, ultrasonography; AAA, abdominal aortic aneurysm. The number of individuals in each group and the proportion (%) are indicated. For the US screening, relatives ≥ 50 years of age were invited to participate and the numbers shown represent this age category.

Figure 2

Two AAA families from the Liège AAA Family Study. The proband in each family is indicated with an arrow. Slash across symbol means death. Black squares and circles, males and females, respectively, with AAA. NA, the person did not participate in US screening. US, the person had ultrasonography examination which showed no AAA. The number below each symbol indicates the age of the person at the time of recruitment, which for most individuals was also the age at the time of AAA diagnosis. If these two ages differed, the age at diagnosis is shown in parenthesis.