Study Details Risk of Blindness After Diagnosis of Diabetic Retinopathy

Charles Wykoff, MD, PhD

New research from ophthalmologists across the US is underlining the importance of early intervention in patients with the most common ocular complication associated with diabetes.

An analysis of more than 53,000 eyes, results of the study outline the risk of blindness associated with different forms of diabetic retinopathy and offer insight into a diabetic patient’s risk of blindness after receiving a new diagnosis.

“Despite public health guidelines designed to increase eye screening in patients with diabetes, patients are still presenting with advanced diabetic retinopathy,” wrote investigators. “The current results support the continued need for improved diabetic retinopathy screening, patient education, and care coordination to reduce the burden of diabetes-associated blindness in the US.”

Already a leading cause of sustained blindness among patients with diabetics and expected to impact more than 14 million patients by 2050, investigators sought to describe associations between initial severity of diabetic retinopathy and risk of blindness in patients with newly diagnosed diabetic retinopathy in the US. Led by Charles Wykoff, MD, PhD, of the Retina Consultants of Texas, the current analysis was designed as a retrospective cohort study of patients in the American Academy of Ophthalmology’s Intelligent Research in Sight Registry.

For inclusion in the study, individuals were required to have vision of 20/40 or better and have been diagnosed with new diabetic retinopathy between January 1, 2013 and December 31, 2017. All individuals were also required to be at least 18 years of age. In total, investigators identified 53,535 eligible eyes with a mean follow-up of 662.5 days for inclusion in the analysis.

For the purpose of analysis, the primary exposure of interest was diabetic retinopathy and severity, which was categorized as mild nonproliferation diabetic retinopathy (NPDR, moderate NPDR, severe NPDR, and proliferative diabetic retinopathy. The primary outcome measure of the study was the development of sustain blindness, which investigators defined as study eyes with Snellen visual acuity readings of 20/200 or worse at visits at least 3 months apart that did not improve beyond 20/100.

Of the 53,535 eligible eyes, 678 (10.5%) developed sustained blindness during the follow-up period. Investigators noted PDR eyes made up 10.5% (n=5629) of the study population but 26.5% (n=180) of the eyes that went on to develop sustained blindness.

Results of a Kaplan-Meier analysis indicated eyes with moderate NPDR, severe NPDR, and PDR at index were 2.6, 3.6, and 4.0 times more likely, respectively, to develop sustained blindness after 2 years of diabetic retinopathy when compared to those with mild diabetic retinopathy at index. In Cox proportional hazards model adjusted for index characteristics/development of oculi condition during the follow-up period, investigators found yes with PDR were at more than twice the risk of sustained blindness as eyes with mild NPDR at index (HR, 2.26; 95% CI, 2.09-2.45).

“The global increase in DR-related vision impairment and blindness underscores the importance of actively addressing vision loss in patients with diabetes,” added investigators.

This study, “Risk of Blindness Among Patients With Diabetes and Newly Diagnosed Diabetic Retinopathy,” was published in Diabetes Care.