Title: Feasibility of an alternative pathway for hospital referrals from Diabetic Eye Screening Wales (DESW) for people suspected with sight-threatening diabetic eye disease (diabetic maculopathy).
Funder: Health and Care Research Wales (Welsh Government)

Abstract: Background: Diabetic retinopathy/maculopathy was the leading cause of blindness in the working age population in the UK [1]. However, since 2009-2010 this is no longer been the case [2,3]. A contributory factor is the introduction of national community-based screening programmes in England and Wales. In Wales, this is conducted by the Diabetic Eye Screening Wales (DESW) service. A recent global meta-analysis has estimated the prevalence of vision threatening diabetic retinopathy to be 6% of which diabetic macular oedema, the commonest cause, accounts for 4% [4]. This is predicted to increase three-fold over the coming 25 years [5]. Screening for diabetic retinopathy employs 2-dimensional (2-D) digital photography, with all suspected of having sight threatening changes referred to the Hospital Eye Service (HES) for further review and/or treatment. As non-stereoscopic 2-D digital photography cannot detect retinal thickening (diabetic maculopathy), surrogate markers are employed, which accounts for over- referral of such cases to the HES. Approximately 80% of referrals to ophthalmology are for maculopathy but only 10% of these were listed for treatment at their first appointment [6]. This creates an enormous unnecessary strain on already overstretched HES, whilst causing stress and anxiety for people with diabetes. Aims: The aim of this study is to assess the safety, feasibility, access, acceptability, and cost - effectiveness of the proposed alternative pathway for those with suspect diabetic maculopathy by the DESW. It will allow comparison of the waiting times for HES appointments for cases with true maculopathy and the relative cost-effectiveness to the current process involving direct referral from DESW to HES. Plan of investigation: The study involves the stratified randomisation of people with diabetes who are being referred from DESW to HES for suspected diabetic maculopathy to either 1) undertake OCT imaging and clinical examination at primary care (an optometry/opticians practice) or 2) follow usual care. Evaluation of the pathway will be conducted using a convergent mixed methods approach. The Patient Reported Experience Measure (PREM) questionnaire developed and validated in the Accelerate ‘transforming eye care services’ study which includes health econom ic questions will be adopted and distributed to all participants in the study. Participants will also be asked to participate in interviews to explore additional qualitative themes not covered by the PREM questionnaire. Summary of the potential benefits: This study would concur with Welsh Government priorities of moving as many eye care services as possible from secondary to primary care [7,8]. Engaging with primary care-based optometric services to determine the need for the HES in those suspected with diabetic maculopathy, will free up capacity within the HES for those awaiting specialist/ophthalmologist treatment and monitoring within the HES setting. This alternative pathway would also provide an opportunity to up-skill optometrists through virtual training by ophthalmologists on an on-going basis. The potential benefits of this study to patients are that they will be seen earlier, in an optometry practice of their choosing, closer to home, benefiting from shorter waiting times. If rolled out across Wales. It is anticipated that 1,800 – 2,700 people per year in Wales could avoid unnecessary HES appointments.

Lay abstract: Aim(s) and objective(s) of the research: To assess a primary care based opticians pathway involving virtual review by a consultant ophthalmologist, in the assessment of suspected diabetic maculopathy. Does this pathway work and is it acceptable to people with diabetes, and at what cost? Background: Diabetic eye disease (DED) is a common and feared complication of diabetes which includes both diabetic retinopathy and diabetic maculopathy (fluid build-up affecting the central retina at the back of the eye). In 2020, of 103 million people worldwide with DED, 29 million had vision-threatening DED and 19 million had diabetic macular oedema, which is expected to increase to 161 million, 45 million and 29 million respectively by 2045 [4]. Screening by Diabetic Eye Service Wales (DESW) currently involves taking 2-D (dimensional) digital photographs of the back of the eye (retina), which are then graded. Leakage from damaged capillaries can cause swelling within the central part of the retina (diabetic maculopathy). However, this thickness cannot be seen on traditional 2-D images. Not everyone with diabetic retinopathy has maculopathy. A diagnosis of maculopathy requires a 3-D camera via a technique known as Optical Coherence Tomography (OCT). The OCT is not part of the routine screening but, is available in Hospital Eye Clinics and many optician practices. If any changes are seen in the macular region on 2-D images, the patient requires an OCT scan to see if there is any increased thickness. Many patients do not have increased thickness. Currently after screening, in those patients with macular changes suggestive of diabetic maculopathy, they are referred to the Hospital Eye Clinic (HES) for OCT imaging. Many of these patients will not have increased thickness and the appointment could have been better utilised seeing a different patient with increased thickness that requires treatment. What you hope to discover: The new pathway involves optician practices who have an OCT camera to take the required images and carry out the initial examination. This information will be then be reviewed by an ophthalmologist virtually to decide the management plan. If this pathway is safe and acceptable to people with diabetes, it would reduce the pressure on HES clinics. It will also develop new skills for opticians and allow people to be seen closer to their home, reducing the stress referrals can create. Public involvement: This study has been reviewed by three members of the long-standing diabetes research group public reference panel who have had input into the study design. They felt that this was an important study and could help people referred from the DESW for further assessment and/or treatment. A member of the reference panel is a co-applicant on this application and there will be two additional members of the panel on the study steering committee and so will be involved in the further developing, running, monitoring, assessing and disseminating the results of the study. Dissemination: The findings from this study will be reported to our public reference group, and Public Health Wales, with manuscripts submitted for publication in peer reviewed journals. Presentations at related local, national, and international meetings/conferences will also be undertaken.

Research activity codes: 7.3 MANAGEMENT AND DECISION MAKING;8.1 ORGANISATION AND DELIVERY OF SERVICES
Health categories: EYE;METABOLIC AND ENDOCRINE