Risk factors for visual impairment registration due to diabetic retinopathy in Leeds, 2002–2005

Abstract

AbstractWe undertook a retrospective study of case notes of those patients registered blind or partially sighted due to diabetic retinopathy in the Leeds metropolitan area in the years 2002 and 2005.Both the incidence of visual impairment due to diabetic retinopathy and the relative contribution to total registrations are similar to those observed in other local and national studies. The main risk factors for registered visual impairment were poor glycaemic control prior to ophthalmic review, no prior retinopathy screening, late presentation with symptomatic visual loss, non‐compliance with planned review and laser treatment failure. Most of these risk factors are avoidable. Nearly two‐thirds of patients diagnosed with diabetes mellitus were being screened for diabetic retinopathy. These figures would suggest that the National Service Framework for Diabetes' proposed coverage of 80% by 2006 and 100% by the end of 2007 is achievable. The duration of diagnosed diabetes mellitus at the time of registration was an average of 16 years in this study. This reflects the slow development of sight‐threatening retinopathy and visual loss observed previously. Conventional therapy for diabetic retinopathy with laser photocoagulation reduces the risk of visual loss more effectively than it improves visual function. Despite the increased risk of early worsening of retinopathy seen with intensive glycaemic control in the Diabetes Control and Complications Trial and the UK Prospective Diabetes Study, improved control closer to the time of diagnosis of diabetes mellitus would have helped to provide a sustained reduction in the risk of retinopathy developing or progressing. Both laser treatment failure and non‐attendance may limit the benefits of improved screening coverage. Copyright © 2009 John Wiley & Sons.