Outcomes in Men From the NHS Abdominal Aortic Aneurysm Screening Programme With a Large Aneurysm Referred for Intervention.

OBJECTIVE: The NHS Abdominal Aortic Aneurysm Screening Programme (NAAASP) has been implemented since 2013. Men with a large aneurysm >54 mm, either at first screen or during surveillance, are referred for intervention. The aim of the present study was to explore outcomes in these men and to see whether there was any regional variation in treatment rates and type of repair. METHODS: The study cohort included all men referred to a vascular network with a large abdominal aortic aneurysm (AAA). Basic demographic information, nurse assessment details, as well as outcome data were extracted from the national NAAASP IT system, AAA SMaRT, for analysis. RESULTS: Some 3 026 men were referred for possible intervention (48% first screen, 52% surveillance). Some 448 men (13.3%) either declined (63, 2.1%), or were turned down for early intervention for various reasons (385, 12.7%). Some 8% were declined for medical reasons (true turn down rate). Men referred from surveillance were older, and more likely not to have had elective surgery within three months (16.0 vs. 11.2%; HR 1.37, 95% CI 1.07-1.75, p = .011). Turn down rates did not vary among local programmes, when surveillance men were taken into account. Some 2 624 (87%) men had planned AAA repair, with a peri-operative mortality of 1.3%. Thirty day surgical mortality was lower after EVAR: 0.4% compared with 2.1% after open repair. The method of repair remained consistent year on year, with roughly equal numbers undergoing endovascular (50%) and open surgical repair (48%); 2% unknown. There was regional variation in the proportion treated by endovascular repair: from 20% to 97%. CONCLUSION: The turn down rate after referral for treatment with a screen detected AAA was low, but there remains considerable regional variation in the proportion undergoing endovascular repair. Procedures were undertaken with low peri-operative mortality.

Safety of Men With Small and Medium Abdominal Aortic Aneurysms Under Surveillance in the NAAASP.

BACKGROUND: Population screening for abdominal aortic aneurysm (AAA) has commenced in several countries, and has been shown to reduce AAA-related mortality by up to 50%. Most men who screen positive have an AAA <5.5 cm in diameter, the referral threshold for treatment, and are entered into an ultrasound surveillance program. This study aimed to determine the risk of ruptured AAA (rAAA) in men under surveillance. METHODS: Men in the National Health Service AAA Screening Programme who initially had a small (3-4.4 cm) or medium (4.5-5.4 cm) AAA were followed up. The screening program's database collected data on ultrasound AAA diameter measurements, dates of referral, and loss to follow-up. Local screening programs recorded adverse outcomes, including rAAA and death. Rupture and mortality rates were calculated by initial and final known AAA diameter. RESULTS: A total of 18 652 men were included (50 103 person-years of surveillance). Thirty-one men had rAAA during surveillance, of whom 29 died. Some 952 men died of other causes during surveillance, mainly cardiovascular complications (26.3%) and cancer (31.2%). The overall mortality rate was 1.96% per annum, similar for men with small and medium AAAs. The rAAA risk was 0.03% per annum (95% CI, 0.02%-0.05%) for men with small AAAs and 0.28% (0.17%-0.44%) for medium AAAs. The rAAA risk for men with AAAs just below the referral threshold (5.0-5.4 cm) was 0.40% (0.22%-0.73%). CONCLUSIONS: The risk of rAAA under surveillance is <0.5% per annum, even just below the present referral threshold of 5.5 cm, and only 0.4% of men under surveillance are estimated to rupture before referral. It can be concluded that men with small and medium screen-detected AAAs are safe provided they are enrolled in an intensive surveillance program, and that there is no evidence that the current referral threshold of 5.5 cm should be changed.

Quality assurance for the NHS abdominal aortic aneurysm screening programme in England.

INTRODUCTION: The National Health Service Abdominal Aortic Aneurysm Screening Programme (NAAASP) was introduced in England in 2009 to offer ultrasound screening to men over 65 years, in order to reduce aneurysm-related deaths. This study describes the development of a quality assurance (QA) process and conducts an analysis of the first round of QA visit reports. The aim was to identify themes where local providers can target their efforts for improvement. METHODS: Forty-one providers were assessed over 4 years using a process of QA visits adapted from previously established screening programmes. A mixture of qualitative and quantitative methods was used to analyse the 41 QA reports, which identified a range of recommendations for providers. The data were coded for key words and assigned to themes. The number of recommendations per visit report was compared with experience of the providers and performance against national screening standards. RESULTS: A total of 773 recommendations were made, with an average of 19 per QA visit. Around one third of the recommendations were based on governance and leadership standards, with 43.0 per cent of those based around commissioning and accountability. A significant relationship was seen between number of infrastructure recommendations and performance against standards. CONCLUSION: This review of a QA cycle found that sound infrastructure is key to the success of a local provider.

Modelling the impact of changes to abdominal aortic aneurysm screening and treatment services in England during the COVID-19 pandemic.

BACKGROUND: The National Health Service (NHS) abdominal aortic aneurysm (AAA) screening programme (NAAASP) in England screens 65-year-old men. The programme monitors those with an aneurysm, and early intervention for large aneurysms reduces ruptures and AAA-related mortality. AAA screening services have been disrupted following COVID-19 but it is not known how this may impact AAA-related mortality, or where efforts should be focussed as services resume. METHODS: We repurposed a previously validated discrete event simulation model to investigate the impact of COVID-19-related service disruption on key outcomes. This model was used to explore the impact of delayed invitation and reduced attendance in men invited to screening. Additionally, we investigated the impact of temporarily suspending scans, increasing the threshold for elective surgery to 7cm and increasing drop-out in the AAA cohort under surveillance, using data from NAAASP to inform the population. FINDINGS: Delaying invitation to primary screening up to two years had little impact on key outcomes whereas a 10% reduction in attendance could lead to a 2% lifetime increase in AAA-related deaths. In surveillance patients, a 1-year suspension of surveillance or increase in the elective threshold resulted in a 0.4% increase in excess AAA-related deaths (8% in those 5-5.4cm at the start). Longer suspensions or a doubling of drop-out from surveillance would have a pronounced impact on outcomes. INTERPRETATION: Efforts should be directed towards encouraging men to attend AAA screening service appointments post-COVID-19. Those with AAAs on surveillance should be prioritised as the screening programme resumes, as changes to these services beyond one year are likely to have a larger impact on surgical burden and AAA-related mortality.

Update on the prevention of death from ruptured abdominal aortic aneurysm.

Objectives To monitor the early effect of a national population screening programme for abdominal aortic aneurysm in 65-year-old men. Setting The study used national statistics for death rates from abdominal aortic aneurysm (Office of National Statistics) and hospital admission data in England (Hospital Episode Statistics). Methods Information concerning deaths from abdominal aortic aneurysm (ruptured and non-ruptured) (1999-2014) and hospital admissions for ruptured abdominal aortic aneurysm (2000-2015) was examined. Results The absolute number of deaths from abdominal aortic aneurysm in men and women aged 65 and over has decreased by around 30% from 2001 to 2014, but as the population has increased, the relative reduction was 45.6% and 40.0%, respectively. Some 65% of all abdominal aortic aneurysm deaths are in men aged over 65; women aged 65 and over account for around 31%. Deaths from ruptured abdominal aortic aneurysm in men aged 60-74 (the screened group) appear to be declining at the same rate as in men aged 75 and over. The relative decline in admissions to hospital with ruptured abdominal aortic aneurysm may be greater in men and women aged 60-74 (which contains the screened group of men), than those older, giving the first possible evidence that abdominal aortic aneurysm screening is having an effect. Conclusion The death rate from abdominal aortic aneurysm is declining rapidly in England. There is the first evidence that screening may be contributing to this reduction.