Abstract
Purpose :
To evaluate the prevalence of diabetic retinopathy (DR) and 5-year rates of incident DR, 2-step-or-more progression of DR, as well as progression to proliferative DR along with associated markers in a Danish national cohort.
Methods :
We included all persons in the Danish Registry of Diabetic Retinopathy, who had attended at least one episode of DR-screening in 2013-2018. DR was classified by the International Clinical Diabetic Retinopathy Severity Scale with levels 0-4 indicating increasing severity. Data were linked with various national databases to indicate type and duration of diabetes, marital status, comorbidity, systemic medication and screening facility. Baseline DR-level at the worse eye was used for analysis.
Results :
Among 170,237 persons with diabetes, mean (with interquartile range) age and duration of diabetes were 65.7 (55.5-73.1) and 5.9 (2.2-11.0) years, respectively, 56.6% were male, and 90.0% had type 2 diabetes. DR-prevalence and 5-year incidences of DR, 2-step-or-more progression of DR and progression to proliferative DR were 12.4%, 4.6%, 0.9% and 0.4%, respectively. The highest rates were found in those below 30 years (21.6%, 13.2%, 2.8%, and 1.2%), with type 1 diabetes (44.2%, 16.0%, 3.4%, and 2.3%), duration of diabetes above 20 years (57.3%, 16.2%, 3.5%, and 2.8%), using insulin (31.8%, 11.0%, 2.4%, and 1.3%), and attending screening at a hospital facility (33.6%, 10.3%, 2.6%, and 1.3%). In multivariable models, use of insulin was identified as a leading marker of all four outcomes (odds ratio 2.24, 95% confidence interval [CI] 2.14-2.34, hazard ratio [HR] 1.90, 95% CI 1.78-2.03, HR 2.23, 95% CI 1.94-2.56, and HR 2.68, 95% CI 2.09-3.43). On the other hand, gender, marital status, Charlson Comorbidity Index score, non-insulin glucose lowering therapy, antihypertensive or cholesterol lowering treatment did not consistenly affect the risk of DR. For patients who entered the registry in the years of 2013, 2014 and 2015, risks of progression to proliferative DR decreased continuously (2.13 vs. 0.97 vs. 0.45, and 2.72 vs. 1.12 vs. 0.70 events per 1,000 person-years for 1- and 3-year progression, respectively).
Conclusions :
In a 5-year longitudinal study of a national cohort of persons attending DR-screening, we identified low age, type 1 diabetes, long duration of diabetes, and in particular use of insulin as the most important markers of presence and development of DR.
This abstract was presented at the 2022 ARVO Annual Meeting, held in Denver, CO, May 1-4, 2022, and virtually.