Screening for abdominal aortic aneurysm

Editor—The front cover of the BMJ of 27 November declared that screening for aortic aneurysm does not reduce overall death rates. This headline misrepresents the conclusions of the study itself,¹ let alone evidence from the UK multicentre aneurysm screening study of 68 000 men, which showed that screening halves aneurysm related deaths by reducing risk of rupture.²

Figure 1.

The Australian trial studied 41 000 men aged 65-83, and the authors admit their target group was not suitable.¹ Half the men over 75 invited for screening did not attend and accounted for two thirds of deaths from aneurysm. Among those aged 65-74, not one patient died of aneurysm disease in 8641 men attending screening, compared with 11 deaths in non-attendees and 13 deaths in controls. The authors concluded that the chief reasons for their overall result seemed to have been their failure to identify and exclude men who were unlikely to attend, a substantial proportion being older than 75.

In Britain only suitable men aged 65-74 are invited by and scanned in general practitioners' surgeries. The Australians selected from electoral rolls and scanned people in specialised clinics. The Gloucestershire experience showed general practice based screening achieves 85% compliance,³ compared with 63% in the Australian study. The lesson from Australia, acknowledged by the authors but not the headline, is that aneurysm screening programmes must be designed carefully and monitored rigorously to be effective. A recent survey from the Vascular Society shows national screening programmes for aortic aneurysm to be the highest priority for consultant vascular surgeons in the United Kingdom.