National screening programme for aortic aneurysmBMJ 2004; 328 doi: https://doi.org/10.1136/bmj.328.7448.1087 (Published 06 May 2004) Cite this as: BMJ 2004;328:1087
- Roger M Greenhalgh, professor of surgery
Could make death from rupture a rarity
In 1992 in England and Wales 4515 deaths in men and 1770 in women were certified as being from ruptured abdominal aortic aneurysm, with only 75% of patients with ruptured aneurysms arriving alive at the hospital.1 2 The multicentre aneurysm screening study, a randomised controlled trial, showed a 42% reduction of deaths from abdominal aortic aneurysm by population screening, and, at four years, the cost per quality adjusted life year gained was £28 000, which is expected to fall to £8000 at 10 years.3 4 It has emerged that the 30 day postoperative mortality from elective aneurysm repair is 3% in screened patients from the population compared with 9% in non-screened patients.5 The concept of a national screening programme for aortic aneurysm needed to be tested, and the multicentre aneurysm screening study was an important contribution that has been favourably received.6
What does the National Screening Committee think of this? Its programme director, Dr Muir Gray, says, “the cost benefit analysis in the trial is of very high quality but abdominal aortic aneurysm screening will be delivered effectively and safely only if sufficient resources are made available at local level.” He seeks additional information, “for example about the number of theatre sessions that would be required and the impact the allocation of such sessions would have on other health problems requiring operative intervention such as colorectal cancer.”7 Thus far then, the call for a national screening programme has had a good reception, and more data are sought.
However, others say that the data from the screening study do not fulfil the criteria of the national screening committee “as there is no evidence from randomised controlled trials of overall survival benefit and no evidence that benefit outweighs the physical and psychological harm of screening.”8 Certainly blunders in breast cancer screening have been reported in the national press, and we need to understand that the advantages of screening must outweigh disadvantages.
The Gloucestershire aneurysm screening project is reported in this week's BMJ as a potential model for a national screening programme.9 Men reaching 65 years were screened in the county from 85 general practices. After 13 years, as more elective operations are done, the incidence of ruptured aneurysm has fallen progressively.
A national screening test needs to be simple, safe, precise, and validated. Repeatability of abdominal aortic aneurysm measurement can be improved to within 4 mm by using a single type of B-mode ultrasound scan and a single observer,10 but it is possible to teach the technique for aortic aneurysm with a simple mobile ultrasound device achieving the even better repeatability of 2-3 mm as shown in the UK small aneurysm trial.11 The repeatability of the scan improved if operators' performance was checked regularly. In the Gloucestershire project a single scan only was required for 95% of the county, and the authors suggest 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.
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. To screen patients with atherosclerotic disease, rather than the whole population, is more cost effective,12 just as it is to leave out women altogether, for which political consideration is needed.
The multicentre aneurysm screening study and the Gloucestershire project used criteria from the UK small aneurysm trial to determine which patients should be operated on (aneurysm > 55 mm in diameter, tender, or growth > 10 mm per year). Recent data from Brady et al about to be published in Circulation indicate that smokers have a faster rate of aortic aneurysm expansion, and we anxiously await the results of the endovascular aneurysm repair trials to learn if endovascular repair carries a lower risk of mortality than open repair and at what cost.13 This could influence the enthusiasm for the adoption of national screening but should not be a factor on its own.
If the useful pilot in Gloucestershire were reproduced nationally, the cost could be less than £50m per year, and ruptured abdominal aortic aneurysm could become a national rarity. What a boast for the NHS that would be. It would put an end to the middle of the night dramas with ruptured abdominal aortic aneurysm, and the attendant high costs in blood products, medical and nursing staff at night, and long stays in intensive care. The future could be a properly resourced national screening programme with gradual reduction of surgery for ruptured aortic aneurysm, with its attendant strains on patients' relatives, as well as a reduction in the strain on hospital resources and in the antisocial hours that doctors and nurses are required to work, often against the thrust of the European Working Time Directive.
Education and debate p 1122
Conflict of interest RG was the lead applicant of the UK small aneurysm trial (funded by the Medical Research Council and British Heart Foundation) and the UK endovascular aneurysm repair trials (funded by the NHS R&D Health Technology Assessment) and a recent board member of the MRC.