Diabetic retinopathy: Implications for the health care sector

A recent systematic review of 35 population-based studies showed that the prevalence of diabetic retinopathy, proliferative diabetic retinopathy, diabetic macular oedema and vision threatening diabetic retinopathy amongst people with diabetes is 34.6%, 7.0%, 6.8%, and 10.2%, respectively (Yau et al. 2012).

By extrapolating these results to the global number of people with diabetes it is estimated that:

• The number of people with diabetic retinopathy will grow from 126.6 million in 2011 to 191.0 million by 2030
• The number of people with vision threatening diabetic retinopathy will increase from 37.3 million to 56.3 million if no urgent action is taken.

However, in high income countries specific public health efforts have contributed to a declining trend in the prevalence of diabetic retinopathy-related blindness amongst people with both type 1 and type 2 diabetes. For example, a 25 year follow up study from the Wisconsin Epidemiologic Study of Diabetic Retinopathy (WESDR) in the US, found that the annual incidence of proliferative diabetic retinopathy (PDR) was 3.5% between 1980 and 1992 but 1.5% between 1994 and 2007.

There are very few high quality incidence studies in Africa and Asia as yet. A recent study from Malawi found progression from no diabetic retinopathy to vision threatening diabetic retinopathy amongst participants with diabetes was 5 times higher than found in European studies (Burgess et al. 2017).

As you watch this video, consider what the explanation might be for the differences in the reported prevalence trends in diabetic retinopathy between high-income and low- and middle-income country settings?