Diabetes is a disease that affects over 65 million persons in India.[1] Diabetes-related eye disease, of which retinopathy is the most important, affects nearly one out of every ten persons with diabetes, according to point prevalence estimates.[2] However, the prevalence increases with increasing duration of diabetes, and it is common in subjects with high-glucose levels and on more complex regimens. For example, in a study of 17,995 subjects with diabetes from across India, the overall prevalence of retinopathy was about 15%. In subjects on diet control, the prevalence of diabetic retinopathy was 4.4%, on oral drugs, the prevalence was 12.5%, and in subjects on insulin, the prevalence was nearly 27%.[3] Clearly, these results show that increasing duration of diabetes associated with glycemic deterioration requiring increased treatment regimen complexity are all associated with a higher prevalence of retinopathy. Retinopathy assessment is more objective and operator-independent than that of other microvascular complications, and is therefore a better marker for monitoring diabetes-related complications. Retinopathy is duration-dependent, and as endocrinologists succeed in taking care of acute co-morbidities, in an aging diabetic population, the burden of retinopathy is bound to increase. This should be limited by early detection and management of retinopathy aided by prompt referrals and teamwork between the endocrinologists and the ophthalmologists. Therefore, the Indian Journal of Endocrinology and Metabolism (IJEM) has embarked on this special supplement – aimed at documenting the current status of diabetic retinopathy and related health-care management scenario in India. It has been clearly shown that glucose control can reduce the onset and progression of diabetic eye disease. The vast majority of diabetes in the country is treated by general physicians, and training them in the management of diabetes-related complications is the need of the hour. Like diabetic neuropathy and nephropathy, retinopathy too can be detected early. Making a dilated fundus examination by trained ophthalmologists is the norm in referral centers specializing in endocrinology and diabetes. But, what about primary care practitioners with little access to such facilities? Simple handheld ophthalmoscopes can, but do not completely supplement the need for a specialist examination. Technology is coming to help, as there are nonmydriatic fundus cameras which screen for retinopathy in a matter of minutes. Mobile eye clinics with the ability to screen for retinal disease are practicable solutions.[4] Mobile diabetes clinics (different from mobile eye clinics) which carry out screening of eye, foot, and kidney disease, bringing diabetes care to the door step, have been another innovation, as they are diabetes-specific and also screen for complications beyond retinopathy.[5] Finally, the stage is set for the arrival of the smartphone as a tool for retinopathy diagnosis, as technology start-ups are increasingly applying point of care; smartphone-based retinal photography to augment the diagnosis.[6] Retinal therapies, consisting of anti-vascular endothelial growth factor agents such as aflibercept, bevacizumab, or ranibizumab, and surgical approaches are all excellent tools in the hands of ophthalmologists.[7] However, as the average reader of IJEM would ask - How best can an endocrinologist prevent diabetic retinopathy? Well, glucose control is probably the most important factor, and keeping the glycated hemoglobin close to 6.5% without hypoglycemia can help. While a sudden control of blood glucose levels may cause a transient deterioration of retinopathy in the long term, strict glucose control will help eventually reduce complication risk. Individuals with type 2 diabetes and pre-existing retinopathy are more prone to such deterioration after intensive glucose control, when compared to subjects without baseline retinopathy.[8] In landmark diabetes intervention studies such as Diabetes Control and Complications Trial and the United Kingdom Prospective Diabetes Study, in addition to glucose control, the control of hypertension was shown to be quintessential.[9,10] Studies focusing on lipid control have also shown a trend toward a favorable outcome in retinopathy.[11,12] Given that endocrinologists see tertiary-level cases, which are more likely to represent advanced disease, a prompt referral to an ophthalmologist is very important to prevent and treat diabetic retinopathy. This supplement, designed to document the current status of diabetes-related eye care infrastructure in the country, is a valuable resource for physicians, diabetologists, and endocrinologists. In addition to the estimates of the burden of disease in the country, the document also suggests the need for an increased national focus on this cause of avoidable blindness.
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