AAA screening: UK programme’s 10-year anniversary prompts renewed push for increasing uptake

The UK’s NHS Abdominal Aortic Aneurysm (AAA) Screening Programme (NAAASP) is fast approaching its 10th anniversary—a milestone that Akhtar Nasim (Sheffield Vascular Institute, Sheffield, UK) and Meryl Davis (Royal Free London NHS Foundation Trust, London, UK) believe provides an opportunity for reflection on progress made, and consideration of future challenges.

IN AN INTERVIEW WITH VASCULAR NEWS —conducted at the 2022 Vascular Society of Great Britain and Ireland (VSGBI) annual scientific meeting (23–25 November, Brighton, UK)—Nasim and Davis looked back on how much has changed with regard to AAA screening in the UK. According to Nasim, clinical lead for the NAAASP in England, a “huge amount of progress” has been made in the years since the MASS (Multicentre aneurysm screening study) trial was published in 2002. In 2008, the UK Government’s Department of Health introduced the AAA screening programme, he noted in particular, which became fully operational five years later.

In the decade since, Nasim reports that around three million men have been offered screening, over two million have taken up the offer, 8,000 men who reached the threshold size have been referred for AAA surgery, and around 6,000 have been operated on. He relayed “excellent” results in terms of 30day mortality, at around 1.22% overall for both endovascular and open surgery. Davis, who is the AAA screening lead for North London, based at the Royal Free Hospital, highlighted some organisational changes that have occurred over the years. She noted for example that in 2018, the North London aneurysm screening programme was created. This initiative combined services for North Central, North West, and North East London and has seen “huge achievements” in terms of the provision of screening services, she informed Vascular News

Both Nasim and Davis acknowledged that there have been obstacles along the way. Davis noted that that the restoration of services amidst the COVID-19 pandemic has been an ongoing challenge in recent

with implementing a national screening programme?

There are several cost-effectiveness studies on screening and the cost of quality-adjusted life years (QALYs) from Sweden, the UK and also from Denmark. The cost per QALY is different in these studies, being less expensive in Denmark.

Of course the whole set-up is expensive as you have to cover the whole country, train nurses and build a system where all the people who meet the screening criteria will be invited to their appointment. Secondly, the number of elective aneurysm repairs is increasing, causing further expenses. At the same time, however, the incidence of ruptured aneurysms is decreasing, which will have the effect of lowering costs and, more importantly, decreasing the rate of ruptured AAA mortality. Whilst a decreasing prevalence of AAA may challenge the cost-effectiveness of a screening programme, modelling data shows that screening is cost-effective down to a prevalence of 0.5%.

Patient involvement and adequate population information are also crucial factors in a successful screening programme. It is known that individuals who do not attend screening are often socioeconomically disadvantaged, and at higher risk for having AAA. Thus, focused efforts to make screening accessible in such populations are of paramount importance.

years, referencing her involvement in helping the North London screening programme “come back up to speed” since late 2021. “We all think that COVID-19 has disappeared, that it is very much in the background,” she said, going on to warn against overlooking the enduring impact of the pandemic.

This year will mark the 10th anniversary of the NAAASP being fully operational—a milestone which Nasim remarked should be seen as an “opportunity to highlight the programme and particularly encourage men that may have missed screening or those that have not taken up the offer of screening”.

Considering the impact of the programme so far, Nasim pointed to “some signs in the ONS [Office for National Statistics] mortality data” that it has begun to have a beneficial effect. Despite this, Davis emphasised the importance of increasing uptake for AAA screening in general, and especially among men from deprived communities. “We have to work together with those communities to reassure them,” Davis urged, highlighting certain steps being taken on a national level to address this issue, including a “toolkit” to allow local providers to try and work out strategies for how to increase participation in screening among low-uptake communities.

UK-COMPASS maps out complex aneurysm treatment in England, points to possible overtreatment

Data from UK-COMPASS (UK complex aneurysm study) were presented for the first time at the 2022 Vascular Society of Great Britain and Ireland (VSGBI) annual scientific meeting (23–25 November, Brighton, UK).

UK-COMPASS IS A COHORT study of 2,202 patients treated across all hospitals in England over a consecutive two-year period. Speaking to Vascular News, lead investigator Srinivasa Rao Vallabhaneni (University of Liverpool, Liverpool, UK) reports that researchers were able to show “extremely good results” out to three years across three groups of patients based on aneurysm neck length: pararenal (0–4mm), juxtarenal (5–9mm), and those 10mm or more that were deemed unsuitable for an on-label, standard endovascular aneurysm repair (EVAR). Vallabhaneni notes that, in the pararenal group, both open repair and fenestrated repair are being delivered with “very good safety”.

At the VSGBI annual meeting, Shaneel Patel (Royal Liverpool University Hospital, Liverpool, UK) delivered a presentation on study and corelab methods, after which Michael Jenkins (Imperial College Healthcare NHS Foundation Trust, London, UK) outlined early results. He shared the headline finding that open repair does worst, EVAR does best, and FEVAR is “in between” with regard to perioperative (in-hospital and 30-day) mortality. Jenkins specified that these results were “fairly consistent” across neck lengths, and also noted a high rate of secondary interventions.

Later in the session, Jon Boyle (Cambridge University Hospitals NHS Trust, Cambridge, UK; see page 16 for profile) outlined results out to median follow-up. Reporting unadjusted allcause mortality at three years, he noted a “significant divergence” of results just beyond a year favouring open repair in terms of survival, and at a three-year mortality rate of around 21%.

“In the long term, you have got about twice the risk of dying if you have had an EVAR over open repair, and similarly about twice the risk if you have had FEVAR [fenestrated EVAR] over open repair at long-term follow-up,” the presenter informed attendees.

Looking specifically at the different treatment groups, Boyle noted that, if a patient with no aortic neck has a standard EVAR, survival in the long term is “significantly worse” than with either open repair and FEVAR—groups in which he noted the outcomes are similar. For longer aortic necks, Boyle stated that open repair in the longer term has better outcomes than both EVAR and FEVAR, and that in patients with aortic necks greater than 10mm in diameter, open repair has “significantly better” outcomes at three years.

In terms of secondary interventions, he said that “not surprisingly,” there were “significantly greater numbers” of reinterventions within the first three years if a patient had EVAR or FEVAR, and that results were “significantly worse” with FEVAR than with EVAR.

“In conclusion,” Boyle relayed, “there is no doubt that the longer-term all-cause mortality is significantly better for open repair,” noting a hazard ratio (HR) for EVAR of around 2.27 and