Risk factors and diabetic retinopathy progression

People with diabetes are 25 times more likely than the general population to become blind. Diabetes has many manifestations in the eye, of which cataracts and diabetic retinopathy (DR) are the most significant causes of visual impairment and blindness. DR is the leading cause of visual impairment and blindness in working adults under 75 years. Visual impairment due to DR has a significant impact on people with diabetes’ quality of life, compromising their ability to manage their diabetes and increasing the risk of other diabetic complications and a lower life expectancy.

To plan and manage diabetic eye care services, collecting and following patient data over time (longitudinal data) is essential to identify the true extent of diagnosed retinal complications from diabetes in the population. A few large epidemiological studies, mostly from high income countries have provided information on DR incidence and disease progression. These studies, the Wisconsin Epidemiological Study on Diabetic Retinopathy, the Diabetic Retinopathy Study (DRS),the Early Treatment of Diabetic Retinopathy Study (ETDRS), the Diabetes Control and Complications Trial (DCCT), the Diabetic Retinopathy Vitrectomy Study (DRVS), and the UK Prospective Diabetic Survey followed patients for many years and are regarded as “gold standards”. The information provided by these studies has been used to develop guidelines for the care of people with diabetic retinopathy.

However, many of these important large scale studies are now dated. More recent studies have been more limited in scope and have found some confounding or conflicting results due to their smaller sample sizes. In addition, a number of these studies have been clinic-based rather than to population-based. When examining the literature on diabetic eye disease we need to remember that these smaller studies are valuable but that their findings may not be generalisable and may overestimate the frequency and severity of disease.

In this video we examine the main risk factors for DR progression, assess the evidence on risk factors and disease progression and relate the risk factors to the incidence of visual loss from DR. As you watch, consider how incidence data guides the development of appropriate prevention strategies for DR generally and within your setting.