HEMOSTATIC FACTORS, ATHEROSCLEROSIS AND RISK OF ABDOMINAL AORTIC-ANEURYSM

Abdominal aortic aneurysms have traditionally been thought to be a con sequence of severe atherosclerosis of the arterial wall. To date, the role of haemostatic factors in aneurysmal disease has not been extensi vely researched. The aim of this study was to see if such factors were independently related to the occurrence of aortic aneurysm. Furthermo re, were the associations maintained after taking into account the pre sence of underlying atherosclerotic disease! Using data from the Edinb urgh Artery Study, a nested case-control design was used involving 40 cases of aortic aneurysm, each being matched to five controls by sex a nd within a 5-year age band. After adjustment for age and sex, both fi brinogen (P less than or equal to 0.01) and fibrin D-dimer (P less tha n or equal to 0.001) were each associated with a significant increased risk of aneurysm. Further adjustment for packyears, history of cardio vascular disease and the ankle brachial pressure index resulted in odd s ratios of 1.51 (95% CI 1.05 to 2.16, P less than or equal to 0.05) f or fibrinogen and 3.75 (95% CI 1.80 to 7.82, P less than or equal to 0 .001) for fibrin D-dimer. These associations probably arise as a conse quence of fibrin deposition and turnover within the aneurysmal sac, al though further prospective studies are needed before thrombotic factor s can be used in the identification of a group who are at high risk of developing an abdominal aortic aneurysm.