The incidence of retinopathy 10 years after diagnosis in young adult people with diabetes: results from the nationwide population-based Diabetes Incidence Study in Sweden (DISS)

OBJECTIVE: To estimate the prevalence and severity of diabetic retinopathy (DR) 10 years after diagnosis in a nationwide population-based cohort study of young adult diabetic patients in Sweden. RESEARCH DESIGN AND METHODS: The Diabetes Incidence Study in Sweden (DISS) aims to register all incident cases of diabetes aged 15-34 years in Sweden. In 1987-1988, 806 cases were reported, and 627 (78%) of them were followed up with regard to retinopathy 8-10 years later. The assessment was based on retinal photographs in most cases (86%). RESULTS: Ten years after diagnosis, retinopathy was found in 247 patients (39%). The retinopathy was mild in 206 (33%), whereas 30 (4.8%) patients had moderate nonproliferative DR (NPDR) and 11 (1.8%) had proliferative DR (PDR). Patients with retinopathy had worse glycemic control during the years than patients without (HbA(1c) 8.1 +/- 1.5% and 6.8 +/- 1.2%, respectively; P < 0.001). In a Cox regression analysis, time to retinopathy was related to high HbA(1c) (P < 0.001) and high BMI (P = 0.001). Patients with type 2 diabetes had an increased prevalence of severe retinopathy (NPDR or PDR) compared with those with type 1 diabetes (14 of 93 [15%] versus no or mild 24 of 471 [5%], respectively; P < 0.001). CONCLUSIONS: Despite modern diabetes management, 39% of young adult diabetic patients developed retinopathy within the first 10 years of the disease. Nevertheless, compared with the prevalence of retinopathy (63%), after a similar duration of diabetes before the Diabetes Control and Complications Trial, this prevalence was clearly lower. Current treatment aimed to achieve strict glycemic control has reduced the risk for developing retinopathy.