Risk factors in 50-year-old men predicting development of abdominal aortic aneurysm.

Background: Abdominal aortic aneurysm (AAA) is a potentially lethal condition associated with several well-known risk factors including age, smoking, and male sex. The aim of this study was to identify risk factors predicting future development of AAA, which could influence future prevention strategies.

Methods: This study collected the data sets of the Westmannia Cardiovascular Risk Factors Study (WICTORY) from 1990 to 1999 and combined them with cases of individuals who have undergone ultrasound examination of the infrarenal aortic diameter as part of the Västmanland County's ongoing AAA screening program that commenced in 2007 or for other purposes. The study analyzed 5817 men aged 50 years at the time they participated in WICTORY and who underwent an ultrasound examination of the infrarenal aorta on average 15 years later.

Results: The prevalence of AAA in our study was 2.6%. Age, smoking status, angina pectoris treatment, prior myocardial infarction, blood pressure treatment, body mass index, waist circumference, systolic blood pressure, heart rate, and total cholesterol level were found to be associated with the development of AAA later in life in the univariate analysis. In the multivariate analysis, current smokers at age 50 years had 11 times higher risk for later development of AAA (hazard ratio [HR], 11.178; confidence interval [CI], 6.277-19.908; P < .001). Former smokers did not suffer a similar risk of AAA development. Elevated total cholesterol concentration at baseline was associated with later AAA development (HR, 1.275; CI, 1.119-1.451; P < .001), as were increasing age (HR, 1.702; CI, 1.153-2.512; P = .007) and waist circumference (HR, 1.019; CI, 1.002-1.037; P = .031).

Conclusions: Both the well-known and the somewhat less established possible predictors for future development of AAA identified in this study can support improvement of strategic preventive measures toward specific risk groups and thereby possibly reduce the risk for development of AAA later in life or at least increase the possibility of an early diagnosis in patients with intact AAA.