Title : Saving sight or losing time evaluating proliferative diabetic retinopathy referral to treatment pathways in two major NHS boards
Abstract:
Introduction: Diabetes Mellitus affects over 4.6 million adults in the UK; 90% will develop diabetic retinopathy (DR) within 20 years of diagnosis. Diabetic eye screening (DES) is vital for the early detection and effective management of DR. R4 is referable retinopathy (proliferative-PDR) requiring urgent referral to Ophthalmology. Diabetic retinopathy screening standards published by Health Improvement Scotland (June 2016) recommends that patients referred from DES for high risk PDR, can access treatments within 5 working days, and low risk PDR within 20 working days of referral. Diabetic Retinopathy Study found that prompt laser (PRP) for patients with high-risk PDR decreases the risk of severe vision loss by 50%, concluding that PRP can be considered for severe NPDR or mild PDR, but recommended prompt PRP for high-risk PDR. RCOphth guidelines state that wherever possible, PRP should be delivered the same day or arranged within 2 weeks from diagnosis of high risk PDR.
Aim: To evaluate the effectiveness of referral-to-treatment pathways for patients with PDR (R4) from Diabetic Eye Screening to ophthalmology services within two major Scottish health boards, assessing the accuracy of diagnoses, management outcomes, and whether treatment was delivered within the Royal College of Ophthalmologists’ recommended timelines, identifying potential delays in care
Methods: Patients referred from Diabetic Eye Screening (DES) to ophthalmology as R4 between 01/01/2022 and 31/12/2022 were included from NHS Grampian (N=196), and between 03/2023 and 03/2024 from NHS Tayside (N=241). In both health boards, all R4 referrals were reviewed by a senior ophthalmologist to confirm urgency and determine the appropriate clinic pathway, including direct laser treatment or other retinal clinics depending on severity. Patient data were collected from DES databases, electronic patient records on Trakcare, and Medisoft. Time intervals from referral to clinic and from clinic to treatment were extracted to assess adherence to recommended treatment timelines.
Results: In NHS Grampian, 61% of R4 referrals from DES were confirmed as proliferative diabetic retinopathy. Among high-risk patients, 50% were seen in clinic within 2 weeks, and 62% received treatment within 2 weeks of confirmed diagnosis. Direct booking into dedicated laser clinics enabled the shortest treatment times.
In NHS Tayside, 59% of R4 referrals were confirmed. Of 91 patients, only 6 (12%) received treatment within the recommended 4-week timeframe from referral. Average intervals were: referral-to-clinic 36.7 days, referral-to-treatment 64.9 days, and clinic-to-treatment 31.2 days. Delays were mainly due to pre-treatment investigations and scheduling constraints.
Conclusion: Diagnostic accuracy for R4 referrals is similar across NHS Grampian and NHS Tayside. However, Grampian achieved substantially faster treatment delivery, with direct laser clinic appointments reducing delays. In contrast, Tayside experienced prolonged referral-to-treatment times, highlighting the need to streamline pathways to ensure timely vision-saving interventions for high-risk PDR patients.
