The gals are screen with envy

Aortic aneurysm screen shown to save lives � but only in men

By Phillipa Rispin

Is screening for aortic aneurysms an effective way to save lives? The short answer is yes � but the story gets complicated after that.

The question was triggered by a study in the May 8 issue of the British Medical Journal (BMJ). Since 1990, all men reaching the age of 65 in the English county of Gloucestershire were offered a simple ultrasound scan of their abdominal aorta at their local general practice. Each year about 3,000 men have been invited for screening. Dr JJ Earnshaw and co-investigators reported that "after 13 years, the mortality from aneurysm disease among men in Gloucestershire has fallen, together with the number of patients with ruptured aortic aneurysm. Over the past decade, the number of elective operations on abdominal aortic aneurysms detected by screening has increased and the number of operations on incidental and ruptured aneurysms has fallen. In addition, mortality from elective repair of screen detected aneurysms (3%) is significantly less than that for incidentally discovered aneurysms (9%)."

A related editorial by Dr Roger M Greenhalgh called the Gloucestershire experience "a potential model for a national screening program." So, it seems that a simple, fast test can make significant differences in lives and healthcare costs. According to the study authors "a single scan can largely rule out aneurysm disease for life in 95% of men." So where does the story get complicated?

Dr Greenhalgh expressed his mixed feelings, noting that "gradual introduction of increased elective surgery in men over 65 years old would extend surgical workload by a manageable amount. However, if all men over 65 were suddenly screened, vascular services would be overwhelmed." This does not even account for women, who also experience these aneurysms, albeit at a much lower prevalence than men.

Dr Greenhalgh points out that "screening of patients with peripheral arterial disease in the United States � 'legs for life' � has suggested that 25% of participants are at risk of ruptured abdominal aortic aneurysm. [Thus] to screen patients with atherosclerotic disease, rather than the whole population, is more cost effective, just as it is to leave out women altogether, for which political consideration is needed."

In Canada, screening, let alone screening women as well as men, is not yet an issue. Interestingly though, a report from Statistics Canada reached some disturbing conclusions. The report found that rates of elective and emergency surgery for inpatients of Canadian hospitals were lower for women. But "gender differences in . . . prevalence, hospitalization rates, age, and contraindications for surgery cannot explain the differences. Possible gender bias in the decision to operate could not be ruled out." So, should women have been included in this study after all? The plot thickens.