An economic evaluation of an abdominal aortic aneurysm screening program in Italy
ABSTRACT Abdominal aortic aneurysm (AAA) is defined as a localized dilatation of an aortic vessel. Though predominantly asymptomatic, it is a chronic degenerative condition associated with life-threatening risk of rupture. The early diagnosis of AAA, ie, before it ruptures, is therefore important; a simple, effective diagnostic method is ultrasound examination. To assess the benefit of screening in Italy, we developed a cost-effective Markov model comparing screening vs nonscreening scenarios.
A 13-health-states Markov model was developed to compare two cohorts of 65- to 75-year-old men: the first group undergoing screening for AAA by means of ultrasound (US), the second following the current practice of incidental detection. The following health states were distinguished: no AAA, unknown small AAA (3-3.9 cm), followed-up small AAA (1 year), unknown medium-sized AAA (4-4.9 cm), followed-up medium-sized AAA (6 months), unknown large AAA (>5 cm), elective repair, emergency repair, postelective-repair AAA, postemergency-repair AAA, rejected large AAA, and death. Transitions between health states were simulated by using 6-month cycles. Transition probabilities were derived from a literature review of relevant randomized controlled trial and from a screening program that is currently ongoing at San Martino Hospital in Genoa, Italy. The Italian National Health Service (NHS) perspective was adopted and incremental cost per life-year saved was calculated with a lifetime horizon; costs and health benefits were discounted at an annual rate of 3% from year 2 onward. Uncertainty surrounding the model inputs was tested by means of univariate, multivariate, and probabilistic sensitivity analyses.
Considering an attendance rate of 62%, the individual cost per invited subject was €60 (US $83.2); 0.011 additional quality adjusted life years (QALY) were gained per patient in the screened cohort, corresponding to an incremental cost-effectiveness ratio (ICER) of €5673/QALY (US $7870/QALY). The results were sensitive to some parameter variations but consistent with the base case scenario. They suggest that on the basis of a willingness-to-pay threshold of €50,000/QALY, screening for AAA is cost-effective, with a probability approaching 100%.
As in economic evaluations developed in other countries, such as the UK, Canada, and The Netherlands, setting up a screening program for AAA can be considered cost-effective from the Italian NHS perspective.
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ABSTRACT: Serving as the basis for implementation of several national AAA screening programmes, four large randomised controlled trials provided evidence of a reduction in AAA mortality by ultrasound-based screening among elderly men. Recently, reports of falling AAA prevalence and mortality unrelated to AAA screening have emerged, coinciding with major additional epidemiological changes in the population, as well as improvements in AAA repair. These recent changes may individually, and in concert, affect the rationality of AAA screening. The aim of this paper was to present an up-to-date review of AAA-screening within the context of a rapidly changing AAA epidemiology. Topical review of the literature focusing mainly on randomised controlled trials, meta-analyses, and contemporary observational AAA-screening studies. Summarising RCT results and recent studies; contemporary one-time screening of men for AAA appears highly cost-effective, and seems to remain an effective preventive health-measure. However, several issues regarding screening need to be addressed: most importantly; the current degree of incidental detection of AAAs, the threshold diameter for follow-up, targeted screening in risk groups, and the possible need for re-screening in an elderly population with ever increasing longevity. Copyright © 2014 European Society for Vascular Surgery. Published by Elsevier Ltd. All rights reserved.European Journal of Vascular and Endovascular Surgery 12/2014; 48(6):659-667. DOI:10.1016/j.ejvs.2014.08.029 · 3.07 Impact Factor
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ABSTRACT: 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).ResultsThe 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.British Journal of Surgery 07/2014; 101(8). DOI:10.1002/bjs.9528 · 4.84 Impact Factor
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ABSTRACT: Abdominal aortic aneurysm (AAA) is a prevalent and potentially life-threatening disease. Early detection by screening programs and subsequent surveillance has been shown to be effective at reducing the risk of mortality due to aneurysm rupture. The aim of this review is to summarize the developments in the literature concerning the latest biomarkers (from 2008 to date) and their potential screening and therapeutic values. Our search included human studies in English and found numerous novel biomarkers under research, which were categorized in 6 groups. Most of these studies are either experimental or hampered by their low numbers of patients. We concluded that currently no specific laboratory markers allow screeing for the disease and monitoring its progression or the results of treatment. Further studies and studies in larger patient groups are required in order to validate biomarkers as cost-effective tools in the AAA disease.BioMed Research International 05/2014; 2014:925840. DOI:10.1155/2014/925840 · 2.71 Impact FactorThis article is viewable in ResearchGate's enriched formatRG Format enables you to read in context with side-by-side figures, citations, and feedback from experts in your field.