Overweight, hyperglycemia and tobacco use are modifiable risk factors for onset of retinopathy 9 and 17 years after the diagnosis of diabetes – A retrospective observational nation-wide cohort study

Background The aims of this study were to estimate the risk for diabetic retinopathy (DR) and to identify risk factors. We investigated a nationwide population-based cohort with diabetes diagnosed at age 15–34 years. Patients and methods Of 794 patients registered 1987–1988 in the Diabetes Incidence Study in Sweden (DISS) 444 (56%) patients with retinal photos available for classification of retinopathy participated in a follow-up study 15–19 (median 17) years after diagnosis. Mean age was 42.3 ± 5.7 years, BMI 26.1 ± 4.1 kg/m2, 62% were male and 91% had type 1 diabetes. A sub-study was performed in 367 patients with retinal photos from both the 9 and 17 year follow up and the risk for development of retinopathy between 9 and 17 years of follow up was calculated. Results After median 17 years 324/444 (73%, 67% of T1D and 71% of T2D), had developed any DR but only 5.4% proliferative DR. Male sex increased the risk of developing retinopathy (OR 1.9, 95% CI 1.2–2.9). In the sub-study obesity (OR 1.2, 95% CI 1.04–1.4), hyperglycemia (OR 2.5, 95% CI 1.6–3.8) and tobacco use (OR 2.9, 95% CI 1.1–7.3) predicted onset of retinopathy between 9 and 17 years after diagnosis of diabetes. Conclusion The number of patients with severe retinopathy after 17 years of diabetes disease was small. The risk of developing retinopathy with onset between 9 and 17 years after diagnosis of diabetes was strongly associated to modifiable risk factors such as glycemic control, obesity and tobacco use