Diabetic Retinopathy Management

Disease Characteristics

Diabetic retinopathy can be classified into two main categories: Non-proliferative diabetic retinopathy (NPDR) and Proliferative diabetic retinopathy (PDR), with NPDR further classified as mild, moderate, or severe, and PDR characterized by neovascularization, vitreous/preretinal hemorrhage 1, 2, 3
Diabetic macular edema (DME) can occur at any stage of diabetic retinopathy and is classified as with or without central involvement, with classification as apparently absent, apparently present (mild, moderate, and severe), and further evaluation using OCT technology 1, 4, 3
Patients with non-center involved macular edema are often asymptomatic, and symptoms typically correlate with the degree of macular involvement rather than the severity of NPDR itself 2
Clinically significant macular edema is more likely to cause noticeable visual changes compared to mild macular edema 5
Severe non-proliferative diabetic retinopathy (NPDR) is characterized by more than 20 intraretinal hemorrhages in each of four quadrants, definite venous beading in two or more quadrants, and prominent intraretinal microvascular abnormalities (IRMA) in one or more quadrants 2

Patients with mild NPDR have approximately 12% risk of developing clinically significant macular edema within 4 years 2
Moderate NPDR increases this risk to 23% 2
Optimizing blood glucose control can reduce the risk of retinopathy onset and progression, with a 39% decrease in retinopathy progression risk for each 10% decrease in HbA1c, as stated by the American Academy of Ophthalmology 2
Optimizing blood pressure control, using ACE inhibitors and ARBs, can reduce retinopathy progression, although tight targets may not provide additional benefit, as suggested by the American Diabetes Association and the European Society of Cardiology 6, 1
Fenofibrate may slow retinopathy progression, particularly in very mild NPDR, according to the American Heart Association 1, 6

The American Academy of Ophthalmology recommends regular screening examinations due to the asymptomatic presentation of NPDR 5
Initial dilated eye examination is recommended within 5 years of diagnosis for Type 1 diabetes and at diagnosis for Type 2 diabetes, with annual follow-ups, as suggested by the American Diabetes Association 6
Follow-up intervals for patients with diabetic retinopathy are:
Panretinal photocoagulation (PRP) should be considered to prevent progression to proliferative diabetic retinopathy in patients with severe NPDR 2, 4
Intravitreal anti-VEGF agents (ranibizumab, aflibercept, or bevacizumab) may be beneficial for patients with severe NPDR and concurrent diabetic macular edema 4
Focal/grid laser photocoagulation is recommended for DME without central involvement 1
Anti-VEGF therapy (ranibizumab, aflibercept, bevacizumab) is recommended as first-line treatment for DME with central involvement, with most patients requiring near-monthly administration during the first 12 months, and fewer injections in subsequent years 1, 4
Panretinal photocoagulation (PRP) is the standard treatment for PDR, reducing the risk of severe vision loss from 15.9% to 6.4% in treated eyes, and is most beneficial in advanced baseline disease (disc neovascularization or vitreous hemorrhage) 1, 6, 2

During pregnancy, PDR can worsen significantly, and close monitoring is required to prevent vision loss, with laser photocoagulation recommended to minimize vision loss 7, 8
Pregnancy can cause rapid progression of diabetic retinopathy, and women with pre-existing diabetes who are planning pregnancy should be counseled about the risk of progression, with more frequent monitoring required, as recommended by the American College of Obstetricians and Gynecologists 1, 6, 2
For PDR with concurrent diabetic macular edema, anti-VEGF therapy is preferred as the first-line treatment, especially for central-involved diabetic macular edema, according to the American Diabetes Association 7, 9

Comprehensive management includes optimizing metabolic control, regular follow-ups, and education on the importance of glycemic control and regular eye exams, with the goal of maximizing residual vision and promoting independence 2
Rehabilitation for visual impairment includes correction of refractive errors, low vision aids, home and work adaptations, training in daily living skills, psychological support, and referral to visual rehabilitation services 2