Abstract
Purpose :
Diabetic retinopathy (DR) is the most common long-term complication to diabetes mellitus and the most common cause of visual loss in the working-aged population. In a national 5-year register-based cohort study, we aimed to identify demographic and clinical characteristics of patients, who later developed proliferative diabetic retinopathy (PDR) compared to patients who did not.
Methods :
The study population includes all Danish diabetes patients above 18 years who attended the Danish DR-screening program. We included 147,802 patients from the Danish Registry of Diabetic Retinopathy followed from the 2th of January 2013 to the 30th of December 2018.
We used the first screening episode as index date and included both eyes of patients with and without subsequent development of PDR. We linked data with various national databases in order to investigate relevant clinical and demographic parameters.
A multivariable Cox regression model was performed to measure the hazard ratio (HR) for incident PDR for all relevant demographic and clinical parameters. We used the k-sample test on equality-of-medians and chi-square test for continuous and categorical variables to test for baseline differences between patients with and without incident PDR-progression.
Results :
Subsequent progression to PDR was identified in 1.741 (1.2 %) patients. 5-year rates of progression to PDR were 0.2%, 3.4% and 20.8% for eyes with DR-levels 0, 1, 2, and 3, respectively.
The HR for incident PDR were duration of diabetes (HR 4.40 per 10 years; 95% confidence interval (CI) 3.61 to 5.35), type 1 diabetes (HR 13.16; 95% CI 10.84 to 15.97), Charlson Comorbidity Index score >0 (Score 1 = HR 4.93; 95% CI 4.20 to 5.79; score 2 = HR 2.01; 95% CI 1.51 to 2.68; score ≥3 = HR 3.09; 95% CI 2.16 to 2.68), use of insulin (HR 4.84; 95% CI 3.84 to 6.11), use of anti-hypertensiva (HR 2.35; 95% CI 1.88 to 2.94) and compared to DR-level 0, the risk of progression was increased with DR-level 1 (HR 11.15; 95% CI 8.92 to 13.93), DR-level 2 (HR 23.88; 95% CI 18.63 to 30.61) and DR-level 3 (HR 77.72; 95% CI 57.59 to 104.89).
Conclusions :
In a 5-year longitudinal DR-screening study of an entire nation, longer duration of diabetes, type 1 diabetes, systemic comorbidity, use of insulin and blood pressure lowering medicine, as well as increasing baseline level of DR, independently predicted progression to PDR.
This abstract was presented at the 2022 ARVO Annual Meeting, held in Denver, CO, May 1-4, 2022, and virtually.