Introduction:
Abdominal aortic aneurysm (AAA) is an important manifestation of vascular disease in older age and rupture of an AAA is a life threatening condition. Traditional atherosclerotic disease risk factors, particularly male sex, smoking and hypertension, are known to contribute to the etiology of AAA. However, epidemiologic studies of AAA have often been cross-sectional, and few have employed a prospective cohort design, especially with long follow-up. The objective of this study was to prospectively assess the association between atherosclerotic disease risk factors and hospitalized AAA in 15,722 participants (68% whites) of the ARIC study, a large, community-based cohort.
Methods:
Risk factors were measured at baseline at 45-64 year of age. Clinical AAAs were ascertained through hospital discharge diagnoses or death certificates. Over 15 years of follow-up, a total of 265 AAAs (85.3% whites) were identified, including repair procedures, AAA rupture or dissection, and incidental detection. Multivariable Cox proportional hazard models were used to estimate the association of risk factors with the risk of future AAA.
Results:
Consistent with the literature from prospective studies, we identified age, male gender, white race, smoking, height, total and HDL cholesterols, triglycerides, white blood cell count, and hypertension as risk factors for AAA (Table). In addition, LDL-C, fibrinogen, and peripheral artery disease that were previously reported only in cross-sectional case-control studies were also strongly associated with AAA (Table). Body mass index, diabetes, and alcohol consumption were not associated with AAA occurrence.
Conclusions:
Several lifestyle and clinical variables measured in middle-age were strong risk factors for future AAA during a long follow-up.
Risk Factors in 50-year-old Men Predicting Development of Abdominal Aortic Aneurysm – A prospective Cohort Study with 15 Years of Follow-up
