Optimum screening intervals for people with diabetes and non-sight threatening diabetic retinopathy – a pilot study.

Principal / Lead investigator
Co-investigators / research team
Type of study

Pilot study


Diabetic retinopathy is a complication of diabetes, caused by high blood sugar levels damaging the back of the eye (retina). It can cause blindness if left undiagnosed and untreated. However, it usually takes several years for diabetic retinopathy to reach a stage where it could threaten sight. To minimise the risk of this happening, people with diabetes are recommended to attend diabetic eye screening appointments – annual screening is offered to all people with diabetes aged 12 and over to pick up and treat any problems early on. This pilot study seeks to find out if the current annual screening interval is optimal for those with non-sight threatening diabetic retinopathy.

The Diabetic Retinopathy Screening Service for Wales was commissioned by the Welsh Assembly Government in 2002.  It currently provides annual retinopathy screening for >180,000 persons. However, the escalating number of persons diagnosed with diabetes will require a corresponding greater investment by service providers. Realigning the screening interval so that it is optimal for all levels of diabetic retinopathy instead of the current annual screening for all could potentially reduce the service costs, patient costs and the costs to society.  Therefore, sustaining the quality of service without compromising care is the basis for this application.

Recent evidence from cohort studies and our group suggests that annual screening is not necessary for those without diabetic retinopathy on two previous occasions. This has led to the National Screening Committee UK recommending that the interval should be extended to biennial for those without diabetic retinopathy.

The aim of this pilot study is to find out whether the annual screening interval is optimal for those with non-sight threatening diabetic retinopathy?

Who is the study sponsor?

Cardiff University

Does the study involve commercial partnership activity?


UKCRN portfolio number (if relevant)

To follow


Wellcome Trust Institutional Strategic Support Fund (Cardiff Uni) (Populations Pilot call)

Total grant value


Start date


End date


How could this research potentially benefit patients?

Currently in the UK there are estimated to be 3.2 million people with diabetes and it likely to increase to 5 million by 2025.  Unfortunately, diabetic retinopathy is one of the leading causes of vision loss in the UK and worldwide and for people with diabetes blindness is one of the most feared complications. The ability to successfully prevent vision loss relies on the early detection and timely introduction of treatment of sight threatening lesions.

Further information (e.g. related web link)

To follow

Outputs generated (Reports / Publications / Impact

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