Four-Year Screening Interval and Vision-Threatening Retinopathy in Type 2 Diabetes Patients With Good Glycemic Control

Abstract

ObjectiveTo assess whether vision-threatening retinopathy developed after 4 years in patients with type 2 diabetes with good glycemic control during follow-up. Patients and MethodsUsing data from the Action to Control Cardiovascular Risk in Diabetes and Action to Control Cardiovascular Risk in Diabetes Follow-on studies (conducted from January 1, 2001, to October 14, 2014), we investigated the incidence of vision-threatening retinopathy after 4 years in patients with type 2 diabetes with good or poor glycemic control. Patients with proliferative diabetic retinopathy at baseline were excluded. Vision-threatening retinopathy was defined as severe nonproliferative diabetic retinopathy, proliferative diabetic retinopathy, laser photocoagulation, or vitrectomy. Good and poor glycemic control was defined as mean glycated hemoglobin level less than 7% and 7% or greater during follow-up, respectively. ResultsThis study included 2285 patients. Among patients with no retinopathy at baseline, the 4-year incidence of vision-threatening retinopathy was 0% (0 of 386) and 0.8% (6 of 721) in those with good and poor glycemic control, respectively (P=.54). Similarly, severe retinopathy was not observed at 8 years in patients who did not have retinopathy at 4 years. Among patients with mild to moderate nonproliferative diabetic retinopathy at baseline, the 4-year incidence of vision-threatening retinopathy was significantly higher in those with poor glycemic control than in those with good glycemic control (9.7% [77 of 790] vs 4.4% [13 of 297]; P=.004). Additionally, the remission rate of diabetic retinopathy was low in patients with a long duration of diabetes. Four-year incidences of vision-threatening retinopathy were higher in patients with retinopathy at baseline who had poorer glycemic control and longer durations of diabetes. ConclusionIt may be safe to extend screening intervals for diabetic retinopathy to 4 years or longer in patients with type 2 diabetes with no retinopathy.