How cost-effective is screening for abdominal aortic aneurysms?

OBJECTIVE To provide reliable estimates of the long-term cost-effectiveness of abdominal aortic aneurysm screening in men. METHODS A Markov health economic decision model for screening is described and extrapolated to 30 years. The strategy modelled involves a one-off scan at age 65 years, with annual and three-monthly follow-up scans for small and medium aneurysms, respectively. Referral for elective surgery occurs at an aortic diameter of 5.5 cm. Model parameters are estimated from patient-level data from the UK Multi-centre Aneurysm Screening Study. Model structure is validated on this trial's data, and input parameter uncertainty is addressed by probabilistic sensitivity analysis. Costs and life-years gained are obtained for both screening and no systematic screening strategies. RESULTS Cost-effectiveness improves dramatically when considered over longer timescales. Taking a 30-year perspective, screening for abdominal aortic aneurysms in men is highly cost-effective at 2320 pounds per life-year gained (95% uncertainty interval: 1600 pounds to 4240 pounds). Adjusting life-years for the age-specific health-related quality of life experienced in this population gave a figure of 2970 pounds (95% uncertainty interval: 2030 pounds to 5430 pounds) per quality-adjusted life-year gained. The additional cost of screening the UK male population is estimated to be 19 m pounds per year. CONCLUSIONS The long-term cost-effectiveness of screening for abdominal aortic aneurysms in men is highly attractive and this evidence provides further support for a national screening programme in the UK.