Size thresholds for repair of abdominal aortic aneurysms warrant reconsideration.

BACKGROUND: The historical size threshold for abdominal aortic aneurysm (AAA) repair is widely accepted to be 5.5 cm for men and 5.0 cm for women. However, contemporary AAA rupture risks may be lower than historical benchmarks, which has implications for when AAAs should be repaired. Our objective was to use contemporary AAA rupture rates to inform optimal size thresholds for AAA repair. METHODS: We used a Markov chain analysis to estimate life expectancy for patients with AAA. The primary outcome was AAA-related mortality. We estimated survival using Social Security Administration life tables and published contemporary AAA rupture estimates. For those undergoing repair, we modified survival estimates using data from the Vascular Quality Initiative and Medicare on complications, late rupture, and open conversion. We used this model to estimate the AAA repair size threshold that minimizes AAA-related mortality for 60-year-old average-health men and women. We performed a sensitivity analysis of poor-health patients and 70- and 80-year-old base cases. RESULTS: The annual risk of all-cause mortality under surveillance for a 60-year-old woman presenting with a 5.0 cm AAA using repair thresholds of 5.5 cm, 6.0 cm, 6.5 cm, and 7.0 cm was 1.7%, 2.3%, 2.7%, and 2.8%, respectively. The corresponding risk for a man was 2.3%, 2.9%, 3.3%, and 3.4% for the same repair thresholds, respectively. For a 60-year-old average-health woman, an AAA repair size of 6.1 cm was the optimal threshold to minimize AAA-related mortality. Life expectancy varied by <2 months for repair at sizes from 5.7 cm to 7.1 cm. For a 60-year-old average-health man, an AAA repair size of 6.9 cm was the optimal threshold to minimize AAA-related mortality. Life expectancy varied by <2 months for repair at sizes from 6.0 cm to 7.4 cm. Women in poor health, at various age strata, had optimal AAA repair size thresholds that were >6.5 cm, whereas men in poor health, at all ages, had optimal repair size thresholds that were >8.0 cm. CONCLUSIONS: The optimal threshold for AAA repair is more nuanced than a discrete size. Specifically, there appears to be a range of AAA sizes for which repair is reasonable to minmized AAA-related mortality. Notably, they all are greater than current guideline recommendations. These findings would suggest that contemporary AAA size thresholds for repair should be reconsidered.

Renin-Angiotensin-Aldosterone System Inhibitors Are Associated With Favorable Outcomes Compared to Beta Blockers in Reducing Mortality Following Abdominal Aneurysm Repair.

Background The best medical therapy to control hypertension following abdominal aortic aneurysm repair is yet to be determined. We therefore examined whether treatment with renin-angiotensin-aldosterone system inhibitors (RAASIs) versus beta blockers influenced postoperative and 1-year clinical end points following abdominal aortic aneurysm repair in a Medicare-linked database. Methods and Results All patients with hypertension undergoing endovascular aneurysm repair and open aneurysm repair in the Vascular Quality Initiative Vascular Implant Surveillance and Interventional Outcomes Network database between 2003 and 2018 were included. Patients were divided into 2 groups based on their preoperative and discharge medications, either RAASIs or beta blockers. Our cohort included 8789 patients, of whom 3523 (40.1%) were on RAASIs, and 5266 (59.9%) were on beta blockers. After propensity score matching, there were 3053 matched pairs of patients in each group. After matching, RAASI use was associated with lower risk of postoperative mortality (odds ratio [OR], 0.3 [95% CI, 0.1-0.6]), myocardial infarction (OR, 0.1 [95% CI, 0.03-0.6]), and nonhome discharge (OR, 0.6 [95% CI, 0.5-0.7]). Before propensity score matching, RAASI use was associated with lower 1-year mortality (hazard ratio [HR], 0.4 [95% CI, 0.4-0.5]) and lower risk of aneurysmal rupture (HR, 0.7 [95% CI, 0.5-0.9]). These results persisted after propensity score matching for mortality (HR, 0.4 [95% CI, 0.4-0.5]) and aneurysmal rupture (HR, 0.7 [95% CI, 0.5-0.9]). Conclusions In this large contemporary retrospective cohort study, RAASI use was associated with favorable postoperative outcomes compared with beta blockers. It was also associated with lower mortality and aneurysmal rupture at 1 year of follow-up.

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.

Screening Older Adult Men for Abdominal Aortic Aneurysm: A Scoping Review.

Abdominal aortic aneurysm (AAA) is a potentially fatal condition predominantly affecting older adult men (60 years or over). Based on evidence, preventative health-care guidelines recommend screening older males for AAA using ultrasound. In attempts to reduce AAA mortality among men, screening has been utilized for early detection in some Western countries including the UK and Sweden. The current scoping review includes 19 empirical studies focusing on AAA screening in men. The findings from these studies highlight benefits and potential harms of male AAA screening. The benefits of AAA screening for men include decreased incidence of AAA rupture, decreased AAA mortality, increased effectiveness of elective AAA repair surgery, and cost-effectiveness. The potential harms of AAA screening included lack of AAA mortality reduction, negative impacts on quality of life, and inconsistent screening eligibility criteria being applied by primary care practitioners. The current scoping review findings are discussed to suggest changes to AAA screening guidelines and improve policy and practice.

Economic evaluation in the context of rare diseases: is it possible? / Evaluación económica en el contexto de enfermedades raras: ¿es posible? / Avaliação econômica no âmbito das doenças raras: isto é possível?

This study analyzes the available evidence on the adequacy of economic evaluation for decision-making on the incorporation or exclusion of technologies for rare diseases. The authors conducted a structured literature review in MEDLINE via PubMed, CRD, LILACS, SciELO, and Google Scholar (gray literature). Economic evaluation studies had their origins in Welfare Economics, in which individuals maximize their utilities based on allocative efficiency. There is no widely accepted criterion in the literature to weigh the expected utilities, in the sense of assigning more weight to individuals with greater health needs. Thus, economic evaluation studies do not usually weigh utilities asymmetrically (that is, everyone is treated equally, which in Brazil is also a Constitutional principle). Healthcare systems have ratified the use of economic evaluation as the main tool to assist decision-making. However, this approach does not rule out the use of other methodologies to complement cost-effectiveness studies, such as Person Trade-Off and Rule of Rescue.

El objetivo fue sistematizar las evidencias disponibles sobre la pertinencia de utilizar la evaluación económica para la incorporación/exclusión de tecnología en enfermedades raras. Se realizó una revisión sistemática de la literatura en MEDLINE vía PubMed, CRD, LILACS, SciELO y Google Académico (literatura gris). Los estudios de evaluación económica se originan de la Economía del Bienestar, en la que los individuos maximizan sus utilidades, basándose en la eficiencia de asignación. No existe un criterio ampliamente aceptado para examinar las utilidades, a fin de dar más peso a los individuos con mayores necesidades. Generalmente, los estudios no equilibran asimétricamente las utilidades, todas son consideradas iguales, lo que en Brasil es también un principio constitucional. Los sistemas de salud han ratificado el uso de la evaluación económica como la principal herramienta para ayudar en la toma de decisiones. Sin embargo, este abordaje no excluye el uso de otras metodologías complementarias a los estudios de coste-efectividad, como la técnica de compensación personal o la regla del rescate.

O objetivo deste estudo foi analisar as evidências disponíveis sobre a adequação do uso de avaliação econômica sobre incorporação/exclusão de tecnologias para doenças raras. Foi realizada uma revisão estruturada da literatura, nas bases MEDLINE, via PubMed, CRD, LILACS, SciELO e Google Acadêmico (literatura cinzenta). Os estudos de avaliação econômica têm origem na Economia do Bem-Estar, na qual os indivíduos maximizam suas utilidades, fundamentando-se na eficiência alocativa. Não há um critério amplamente aceito para ponderar as utilidades esperadas, no sentido de dar mais peso aos indivíduos com maiores necessidades em saúde. Geralmente não se ponderam assimetricamente as utilidades; todas são tratadas de forma igualitária, que, no caso brasileiro, também é um princípio constitucional. Os sistemas de saúde têm ratificado o uso de avaliação econômica como principal instrumento para auxiliar na tomada de decisão. No entanto, essa postura não exclui o uso de outras metodologias complementares aos estudos de custo-efetividade, como Person Trade-Off e regra de resgate.

A new aortic injury score predicts early rupture more accurately than clinical assessment.

OBJECTIVE: The optimal timing for repair of a high-grade blunt thoracic aortic injury (BTAI) is uncertain. Delayed repair is common and associated with improved outcomes, but some lesions may rupture during observation. To determine optimal patient selection for appropriate management, we developed a pilot clinical risk score to evaluate aortic stability and predict rupture. METHODS: Patients presenting in stable condition with Society for Vascular Surgery grade III or IV BTAI diagnosed on computed tomography (CT) were retrospectively reviewed. To determine clinical and radiographic factors associated with aortic rupture, patients progressing to aortic rupture (defined by contrast extravasation on CT or on operative or autopsy findings) were compared with those who had no intervention ≤48 hours of admission. A model targeting 100% sensitivity for rupture was generated and internally validated by bootstrap analysis. Clinical utility was tested by comparison with clinical assessment by surgeons experienced in BTAI management who were provided with CT images and clinical data but were blinded to outcome. RESULTS: The derivation cohort included 18 patients whose aorta ruptured and 31 with stable BTAI. There was no difference in age, gender, injury mechanism, nonchest injury severity, blood pressure, or Glasgow Coma Scale on admission between patient groups. As dichotomous factors, admission lactate >4 mM, posterior mediastinal hematoma >10 mm, and lesion/normal aortic diameter ratio >1.4 on the admission CT were independently associated with aortic rupture. The model had an area under the receiver operator curve of .97, and in the presence of any two factors, was 100% sensitive and 84% specific for predicting aortic rupture. No aortic lesions ruptured in patients with fewer than two factors. In contrast, clinical assessment had lower accuracy (65% vs 90% total accuracy, P < .01). CONCLUSIONS: This novel risk score can be applied on admission using clinically relevant factors that incorporate patient physiology, size of the aortic lesion, and extent of the mediastinal hematoma. The model reliably identifies and distinguishes patients with high-grade BTAI who are at risk for early rupture from those with stable lesions. Although preliminary, because it is more accurate than clinical assessment alone, the score may improve patient selection for emergency or delayed intervention.

Cost-effectiveness of the National Health Service Abdominal Aortic Aneurysm Screening Programme in England.

BACKGROUND: Implementation of the National Health Service abdominal aortic aneurysm (AAA) screening programme (NAAASP) for men aged 65 years began in England in 2009. An important element of the evidence base supporting its introduction was the economic modelling of the long-term cost-effectiveness of screening, which was based mainly on 4-year follow-up data from the Multicentre Aneurysm Screening Study (MASS) randomized trial. Concern has been expressed about whether this conclusion of cost-effectiveness still holds, given the early performance parameters, particularly the lower prevalence of AAA observed in NAAASP. METHODS: The existing published model was adjusted and updated to reflect the current best evidence. It was recalibrated to mirror the 10-year follow-up data from MASS; the main cost parameters were re-estimated to reflect current practice; and more robust estimates of AAA growth and rupture rates from recent meta-analyses were incorporated, as were key parameters as observed in NAAASP (attendance rates, AAA prevalence and size distributions). RESULTS: The revised and updated model produced estimates of the long-term incremental cost-effectiveness of £5758 (95 per cent confidence interval £4285 to £7410) per life-year gained, or £7370 (£5467 to £9443) per quality-adjusted life-year (QALY) gained. CONCLUSION: Although the updated parameters, particularly the increased costs and lower AAA prevalence, have increased the cost per QALY, the latest modelling provides evidence that AAA screening as now being implemented in England is still highly cost-effective.

Changes in abdominal aortic aneurysm rupture and short-term mortality, 1995-2008: a retrospective observational study.

OBJECTIVE: To examine the modern epidemiology of abdominal aortic aneurysm (AAA) rupture and short-term AAA-related mortality after the introduction of endovascular aneurysm repair (EVAR). BACKGROUND: Previous epidemiologic studies have demonstrated stable rates of AAA repair, repair mortality, and AAA rupture. Recently, EVAR has been introduced as a less invasive treatment method, and its use has expanded to more than 75% of elective AAA repairs. METHODS: We identified Medicare beneficiaries undergoing AAA repair and those hospitalized with a ruptured AAA during the period 1995 to 2008 and calculated standardized annual rates of AAA-related deaths due to either elective repair or rupture. RESULTS: A total of 338,278 patients underwent intact AAA repair during the study period. There were 69,653 patients with AAA rupture, of whom 47,524 underwent repair. Intact repair rates increased substantially in those older than 80 years (57.7-92.3 per 100,000, P < 0.001) but decreased in those 65 to 74 years old (81.8-68.9, P < 0.001). A decline in ruptures with and without repair was seen in all age groups. By 2008, 77% of all intact repairs and 31% of all rupture repairs were performed with EVAR (P < 0.001). Operative mortality declined during the study period for both intact (4.9%-2.4%, P < 0.001) and ruptured (44.1%-36.3%, P < 0.001) AAA repair. Short-term AAA-related deaths decreased by more than half (26.1-12.1 per 100,000, P < 0.001), with the greatest decline occurring in those older than 80 years (53.7-27.3, P < 0.001). CONCLUSIONS: A recent decline in AAA rupture and short-term AAA-related mortality is demonstrated and likely related in part to the introduction and expansion of EVAR. This is due to decreased deaths from ruptures (with and without repair) and decreased mortality with intact repairs, particularly in patients older than 80 years.

Population screening for abdominal aortic aneurysm: evaluating the evidence against screening criteria.

Screening for abdominal aortic aneurysm (AAA) has been initiated in the United Kingdom and United States. Screening using abdominal ultrasound scans allows AAAs to be detected and electively repaired before rupture. There is currently no policy for AAA screening in New Zealand (NZ). We reviewed literature to assess current evidence for AAA screening against standard criteria used to evaluate population-based screening programmes. AAA rupture has high mortality, and people of Maori ethnicity are disproportionately affected. Abdominal ultrasound is a valid screening tool, and elective repair is an effective treatment. Screening reduces AAA-related mortality by about 40% in elderly men. However, the age and comorbidities of AAA patients means rupture risk has to be weighed against elective repair risk. Overtreatment is likely, given most individuals with AAA will not experience rupture in their lifetime. AAA screening appears to be cost-effective. It is unclear if the health system could support all the elements of a AAA screening pathway. AAA appears to be an appropriate condition for which to consider population screening. We recommend research into the prevalence of AAA in NZ, the comorbidity profile of individuals with AAA, drivers of high mortality among Maori, and acceptability of AAA screening to the New Zealand public.

Cost-effectiveness of screening for abdominal aortic aneurysm in the Netherlands and Norway.

BACKGROUND: The aim of this study was to determine the cost-effectiveness of ultrasound screening for abdominal aortic aneurysm (AAA) in men aged 65 years, for both the Netherlands and Norway. METHODS: A Markov model was developed to simulate life expectancy, quality-adjusted life-years, net health benefits, lifetime costs and incremental cost-effectiveness ratios for both screening and no screening for AAA. The best available evidence was retrieved from the literature and combined with primary data from the two countries separately, and analysed from a national perspective. A threshold willingness-to-pay (WTP) of €20,000 and €62,500 was used for data from the Netherlands and Norway respectively. RESULTS: The additional costs of the screening strategy compared with no screening were €421 (95 per cent confidence interval 33 to 806) per person in the Netherlands, and the additional life-years were 0·097 (-0·180 to 0·365), representing €4340 per life-year. For Norway, the values were €562 (59 to 1078), 0·057 (-0·135 to 0·253) life-years and €9860 per life-year respectively. In Norway the results were sensitive to a decrease in the prevalence of AAA in 65-year-old men to 1 per cent, or lower. Probabilistic sensitivity analyses indicated that AAA screening has a 70 per cent probability of being cost-effective in the Netherlands with a WTP threshold of €20,000, and 70 per cent in Norway with a threshold of €62,500. CONCLUSION: Using this model, screening for AAA in 65-year-old men would be highly cost-effective in both the Netherlands and Norway.

Cost-effectiveness of intensive smoking cessation therapy among patients with small abdominal aortic aneurysms.

INTRODUCTION: Smoking cessation is one of the few available strategies to decrease the risk for expansion and rupture of small abdominal aortic aneurysms (AAAs). The cost-effectiveness of an intensive smoking cessation therapy in patients with small AAAs identified at screening was evaluated. METHODS: A Markov cohort simulation model was used to compare an 8-week smoking cessation intervention with adjuvant pharmacotherapy and annual revisits vs nonintervention among 65-year-old male smokers with a small AAA identified at screening. The smoking cessation rate was tested in one-way sensitivity analyses in the intervention group (range, 22%-57%) and in the nonintervention group (range, 3%-30%). Literature data on the effect of smoking on AAA expansion and rupture was factored into the model. RESULTS: The intervention was cost-effective in all tested scenarios and sensitivity analyses. The smoking cessation intervention was cost-effective due to a decreased need for AAA repair and decreased rupture rate even when disregarding the positive effects of smoking cessation on long-term survival. The incremental cost/effectiveness ratio reached the willingness-to-pay threshold value of €25,000 per life-year gained when assuming an intervention cost of > €3250 or an effect of ≤ 1% difference in long-term smoking cessation between the intervention and nonintervention groups. Smoking cessation resulted in a relative risk reduction for elective AAA repair by 9% and for rupture by 38% over 10 years of follow-up. CONCLUSIONS: An adequate smoking cessation intervention in patients with small AAAs identified at screening can cost-effectively increase long-term survival and decrease the need for AAA repair.

Three strikes--don't die of a broken heart.

There are multiple layers of complexity in prevention of vehicle related blunt traumatic aortic rupture (BTAR), many of which are enshrined within government policy and car design. We present a 'layers of protection analysis' (LOPA) based loosely on original work by Professor John Doyle, which describes these attempts to 'design out' the risk of BTAR following a vehicle collision. We have modified this approach to include a physiological dimension suggesting that this may be a factor in susceptibility to aortic injury following trauma. Understanding processes involved in BTAR following vehicle collisions is key to designing preventative processes.

Abdominal aortic aneurysm: high prevalence in men over 59 years of age with TIA or stroke, a perspective.

Death resulting from a ruptured abdominal aortic aneurysm (AAA) is potentially preventable. Screening for AAA is cost-effective, reducing risk of AAA-related death by 50%. For various reasons screening programs have not been implemented widely. Therefore, the need to identify subgroups with increased prevalence of AAA remains. Recently, men over 59 years of age presenting with stroke or a transient ischemic attack (TIA) at the neurology department were found to have a doubled prevalence of AAA. This confirmed data of another study (SMART), which included broader inclusion criteria (either manifest atherosclerotic disease or only risk factors for atherosclerosis). Incorporation of an aortic ultrasonography into the neurological work up of these patients could result in an effective screening program. However, before that, several cost-effectiveness issues need to be resolved, such as growth rate of the detected aneurysms, risk of death by AAA rupture in this patient group with increased co-morbidity and decreased life expectancy, peri-operative risk of open or endovascular repair.

[Screening for abdominal aortic aneurysm; effectivity and cost-effectiveness]. / Screening op aneurysma aortae abdominalis: effectiviteit en kosteneffectiviteit.

OBJECTIVE: To review the current literature concerning the effectivity and cost-effectiveness of screening for abdominal aortic aneurysm (AAA). DESIGN: Systematic review. METHOD: A review of literature of evaluations of effectivity via meta-analyses and economic evaluations. RESULTS: The short-term meta-analyses showed that screening for AAA leads to a significant reduction of AAA-related mortality. The average absolute risk reduction (ARR) was 0.12%. The long-term meta-analysis also showed a significant reduction of overall mortality. The ARR was in this case almost 1%. The five economic evaluations all resulted in cost-effectiveness ratios below euro 20,000 per quality-adjusted life year (QALY), a used threshold level in the Netherlands. CONCLUSION: Based on the available literature, screening for AAA has appeared to be both effective and cost-effective. However, the economic evaluations did not always take into account the peri- and post-operative mortality and morbidity. Economic evaluations are only useful if all possible outcomes are included in the model. Therefore a good model analysis should be made for the Dutch situation, after which a decision may be taken on a possible pilot study and the optimal design thereof.

Analysis of cost effectiveness of screening Danish men aged 65 for abdominal aortic aneurysm.

OBJECTIVE: To assess the cost effectiveness of screening men aged 65 for abdominal aortic aneurysm. DESIGN: Cost effectiveness analysis based on a probabilistic, enhanced economic decision analytical model from screening to death. POPULATION AND SETTING: Hypothetical population of men aged 65 invited (or not invited) for ultrasound screening in the Danish healthcare system. DATA SOURCES: Published results from randomised trials and observational epidemiological studies retrieved from electronic bibliographic databases, and supplementary data obtained from the Danish Vascular Registry. DATA SYNTHESIS: A hybrid decision tree and Markov model was developed to simulate the short term and long term effects of screening for abdominal aortic aneurysm compared with no systematic screening on clinical and cost effectiveness outcomes. Probabilistic sensitivity analyses using Monte Carlo simulation were carried out. Results were presented in a cost effectiveness acceptability curve, an expected value of perfect information curve, and a curve showing the expected (net) number of avoided deaths from abdominal aortic aneurysm over time after the introduction of screening. The model was validated by calibrating base case health outcomes and expected activity levels against evidence from the recent Cochrane review of screening for abdominal aortic aneurysm. RESULTS: The estimated costs per quality adjusted life year (QALY) gained discounted at 3% per year over a lifetime for costs and QALYs was pound43 485 (euro54,852; $71,160). At a willingness to pay threshold of pound30,000 the probability of screening for abdominal aortic aneurysm being cost effective was less than 30%. One way sensitivity analyses showed the incremental cost effectiveness ratio varying from pound32,640 to pound66,001 per QALY. CONCLUSION: Screening for abdominal aortic aneurysm does not seem to be cost effective. Further research is needed on long term quality of life outcomes and costs.

Screening men for abdominal aortic aneurysm: 10 year mortality and cost effectiveness results from the randomised Multicentre Aneurysm Screening Study.

OBJECTIVES: To assess whether the mortality benefit from screening men aged 65-74 for abdominal aortic aneurysm decreases over time, and to estimate the long term cost effectiveness of screening. DESIGN: Randomised trial with 10 years of follow-up. SETTING: Four centres in the UK. Screening and surveillance was delivered mainly in primary care settings, with follow-up and surgery offered in hospitals. PARTICIPANTS: Population based sample of 67 770 men aged 65-74. INTERVENTIONS: Participants were individually allocated to invitation to ultrasound screening (invited group) or to a control group not offered screening. Patients with an abdominal aortic aneurysm detected at screening underwent surveillance and were offered surgery if they met predefined criteria. MAIN OUTCOME MEASURES: Mortality and costs related to abdominal aortic aneurysm, and cost per life year gained. RESULTS: Over 10 years 155 deaths related to abdominal aortic aneurysm (absolute risk 0.46%) occurred in the invited group and 296 (0.87%) in the control group (relative risk reduction 48%, 95% confidence interval 37% to 57%). The degree of benefit seen in earlier years of follow-up was maintained in later years. Based on the 10 year trial data, the incremental cost per man invited to screening was pound100 (95% confidence interval pound82 to pound118), leading to an incremental cost effectiveness ratio of pound7600 ( pound5100 to pound13,000) per life year gained. However, the incidence of ruptured abdominal aortic aneurysms in those originally screened as normal increased noticeably after eight years. CONCLUSIONS: The mortality benefit of screening men aged 65-74 for abdominal aortic aneurysm is maintained up to 10 years and cost effectiveness becomes more favourable over time. To maximise the benefit from a screening programme, emphasis should be placed on achieving a high initial rate of attendance and good adherence to clinical follow-up, preventing delays in undertaking surgery, and maintaining a low operative mortality after elective surgery. On the basis of current evidence, rescreening of those originally screened as normal is not justified. Trial registration Current Controlled Trials ISRCTN37381646.