Some 5-10 per cent of UK men over 65 have an abdominal aortic aneurysm (AAA) and, for men, it is the 12th most common cause of death.
At present, screening is not offered, even to patients at high risk. If an aneurysm is picked up, usually during treatment or screening for other conditions, then, depending on its size, the patient will either be operated on immediately or monitored.
Elective surgery to repair an aneurysm carries good odds - chances of survival are around 95 per cent.
Many aneurysms are undetected until they rupture. In this instance, the overall chances of survival are low, between 6 and 22 per cent, with 50 per cent of patients dying before they even reach hospital. Treating ruptures requires an emergency operating suite and therefore is very expensive.
A straightforward ultrasound scan can detect an aneurysm. A number of local screening programmes in the UK to screen patients have resulted in an increase in patients diagnosed with aneurysms and a reduction in those dying from rupture.
The Multicentre Aneurysm Screening Study (MASS) evaluated the screening in over 67,000 men aged 65-74 in a randomised controlled trial. It showed that almost half of aneurysm-related deaths could be prevented by early detection and treatment. This equates to 2,000-3,000 deaths in the UK every year.
Professor Buxton, one of the MASS trialists, approached Guy's and St Thomas' Charity for a grant to start a screening programme in south London.The charity provided funding for a three-year screening programme. All 65-year-old men in Lambeth and Southwark will be invited to be screened either at GP practices or at Guy's and St Thomas'.
From the GP's point of view, all they have to do is agree for patients to take part in the programme and, where possible, make a room available in which the ultrasound can take place. All equipment and staff are provided by the programme.
If the ultrasound shows that an aneurysm over 5cm is present, the patient will be referred to the vascular team at Guy's and St Thomas' for further assessment.
Aneurysms less than 5cm are not deemed to be an immediate risk and these patients are put on a surveillance programme of repeat ultrasound scanning.
The optimum age to perform screening is 65 years. There are few occurrences of rupture before that age and if any patient is to have an aneurysm at risk of rupture in the future, it will most likely already be present.
Benefit to patient and GP
A national screening programme would ensure that patients benefit from reduced mortality from aneurysm rupture. It would also be cost-effective, because screening would allow the luxury of time to decide when was best to have a repair operation.
The most common treatment for AAA is an open repair; however, a growing number of consultants now offer endovascular aneurysm repair (EVAR), which is less invasive. This is carried out via two cuts to the groin, and is possible with a new range of smaller, more flexible stent grafts.
Since it requires only regional anaesthetic, EVAR incurs less risk and a shorter recovery time. It also offers the possibility of treatment to some patients who would not otherwise be candidates for repair. A few hospitals, including Guy's and St Thomas', are now offering a 24-hour emergency service to treat ruptured aneurysms with EVAR.
The role for GPs is vital, not simply to provide a screening venue, but also to help raise awareness of this disease and to support those at risk.
The London screening programme has already detected one aneurysm and we have 15 clinics scheduled during May.
Men aged 65 will be invited first, but the programme is also open to both men and women over 65, as part of a comprehensive screening scheme.
- Mr Waltham is a senior lecturer and honorary consultant vascular
surgeon at Guy's and St Thomas' NHS Foundation Trust
The Multicentre Aneurysm Screening Study into the effect of abdominal aortic aneurysm screening on mortality in men: a randomised controlled trial. Lancet 2002; 360: 1,531-9.