Blood Pressure Control and Diabetic Retinopathy

Diabetic retinopathy affects a significant proportion of people with diabetes. Epidemiological studies suggest that hypertension is related to diabetic retinopathy, and major clinical trials has provided clear evidence that controlling blood pressure in diabetic patients with hypertension reduces the incidence and progression of retinopathy and visual loss. The United Kingdom Prospective Diabetes Study (UKPDS) showed that a 10 mmHg reduction in systolic blood pressure is associated with a 10% reduction in the risk of retinopathy. However, the UKPDS suggest that adequate blood pressure control must be maintained over time for sustained benefits on retinopathy and other microvascular complications. Recent trials suggest that there is a limit to retinopathy risk reduction achievable through lowering blood pressure to near normal levels. Newer trials also provide initial evidence that specific inhibition of the renin angiotensin system (RAS), particularly with angiotensin II-receptor blockers (ARB), may have an additional protective effect against retinopathy. Early detection of retinopathy through comprehensive dilated eye examinations by eye care providers, controlling modifiable risk factors (glucose, blood pressure and lipids) and appropriate referral for treatment are the cornerstones in management of diabetic retinopathy in the community.