Lower prevalence than expected when screening 70-year-old men for abdominal aortic aneurysm

Screening 65-year-old men for abdominal aortic aneurysms (AAA) is a cost-effective method to reduce the mortality from ruptured AAA. However, contemporary results show a lower than expected prevalence of AAA, thus questioning the benefit of screening. Since the prevalence increases with age, a possible way to enhance the benefit of screening might be to screen older men. Our aim was to determine the contemporary screening-detected prevalence among 70-year-old men.

A total of 5,623 unscreened 70-year-old men were invited to ultrasound screening. Uni- and multivariable analyses were used to assess the risk factors for AAA.

The attendance rate was 84.0%. The prevalence of previously unknown AAAs was 2.3%. When adding the 64 men with an already known AAA to the screening-detected ones, the total prevalence in the population was at least 3.0%, and the previously discovered AAAs constituted 37.4% of the total prevalence. "Ex smoker" and "Current smoker" were the most important risk factors.

When screening 70-year-old men for AAA, the prevalence was less than half that expected, despite a high attendance rate. Smoking was the strongest risk factor. Almost 40% of the men with AAAs were already known from other means than screening.