INFLAMMATORY ABDOMINAL AORTIC-ANEURYSMS - A CASE-CONTROL STUDY

Purpose: This study was designed to identify significant differences i n the clinical and radiologic characteristics and outcome between pati ents with inflammatory and noninflammatory abdominal aortic aneurysms (AAAs), Methods: We reviewed 29 consecutive patients who underwent rep air of an inflammatory AAA between 1985 and 1994. This group was match ed in a case-control fashion by date of surgery and by the performing surgeon to a group of 58 patients who underwent repair of noninflammat ory AAAs. Results: The two groups had comparable characteristics of ag e, gender, and cardiovascular risk factors. Patients with inflammatory AAAs were significantly more symptomatic than those with noninflammat ory AAAs (93% vs 9%, p < 0.001), were more likely to have a family his tory of aneurysms (17% vs 1.5%, p = 0.007), and tended to be current s mokers (45% vs 24%, p = 0.049). The most significant; laboratory diffe rence was an elevated sedimentation rate in patients with inflammatory AAAs (mean, 53 mm/hr vs 12 mm/hr, p < 0.00001). Inflammatory AAAs als o were significantly larger than noninflammatory AAAs at presentation (6.8 cm vs 5.9 cm, p < 0.05). Although operative mortality was low in both groups, patients with an inflammatory ABA tended to have higher m orbidity including sepsis (P < 0.01) and renal failure (p = 0.01). Fiv e-year survival rates, however, were similar for the two groups (79% f or inflammatory and 83% for noninflammatory AAAs). On follow-up comput ed tomographic scans, the retroperitoneal inflammatory process resolve d completely in 53% of the patients, but 47% of patients had persisten t inflammation that involved the meters in 32% and resulted in long-te rm solitary or bilateral renal atrophy in 47%. Conclusions: This case- control study provides preliminary evidence that inflammatory AAAs may have a relatively strong familial connection and that current smoking may play an important role in the inflammatory response. The study al so documents that persistent retroperitoneal inflammation may be more prevalent than has been previously reported, and stresses the need for an improved understanding of the pathogenesis and long-term managemen t of inflammatory AAAs.