An economic evaluation to assess the feasibility of an optical coherence tomography-based screening programme for neovascular age-related macular degeneration - The PROTECT Study

DESIGN. Economic evaluation supported by targeted evidence synthesis. AIM. To assess the feasibility, effectiveness and cost-effectiveness of an optical coherence tomography (OCT) based screening strategy in the UK for the early detection of progression from dry age-related macular degeneration (AMD) to neovascular AMD (nAMD) in the first eye. BACKGROUND. The most common cause of vision loss and blindness in the UK is AMD. Of the two types, dry AMD is the most common and causes a gradual loss of central vision over many years. The other, nAMD, is a more severe form causing a rapid loss of central vision over weeks or months. Dry AMD progresses to nAMD in around 1 in 15 people, with over 100 people per day diagnosed with nAMD each year in the UK. Because nAMD progresses very quickly and there are effective treatments to stabilise vision, it is important to diagnose nAMD as early as possible to maximise the retention of vision. At present adults are recommended to have an eyesight test every 2 years. Typically, this is when dry AMD is diagnosed. Guidelines recommend that people with a progressive disorder (e.g. dry AMD) can attend an optometrist more frequently but they often don’t, often have to pay and may not have the best technology. They should also self-monitor. We propose that people with dry AMD would benefit from regular, publicly funded frequent observations, using technologies such as OCT scans of the macular to catch progression to nAMD earlier. The introduction of additional screening for people with dry AMD is however likely to be costly and it is unclear which groups of people (if any) should be offered screening and how often this should be done so to catch nAMD earlier in a cost-effective way for the NHS. An economic evaluation is therefore required. METHODS. Work Package 1 (WP1) includes two systematic reviews of primary literature focusing on key inputs for the economic evaluation. The first will address the diagnostic accuracy of the screening tools. The second will address prognostic factors among targeted population groups for progression from dry AMD to nAMD. Evidence will be synthesised using appropriate meta-analytic techniques, where data permits. Where meta-analysis is inappropriate, results will be synthesised narratively. Work Package 2 (WP2) will draw on WP1 results and other sources, to inform a decision analytic model to delineate the most cost-effective approach to screening for nAMD in the first eye. A patient-level simulation will estimate long-term outcomes as a function of personalised risk under alternative screening intervals. Distributional cost-effectiveness analysis will evaluate the equity implications of screening, recognising the impact of socioeconomic factors on engagement with healthcare services. Further primary research requirements to support the implementation of a screening programme will be described in detail. DISSEMINATION. A Threaded Publication plan including a synopsis report summarising our findings will complement submissions to peer-reviewed journals and conference presentations along with our social media websites. In addition, in Work Package 3, an infographic will be produced to disseminate findings in a comprehensive way to the wider public via networks such as the Macular Society. All work will be informed by groups including Patient and Public Involvement and Engagement, Public Health Experts, the National Screening Committee, Ophthalmologists and Optometry advisors.