Association Between Pentoxifylline Use and Diabetic Retinopathy in Patients with Type 2 Diabetes Mellitus and Chronic Kidney Disease: A Multi-Institutional Cohort Study

Background Pentoxifylline is administrated to improve the hemodynamics of patients with chronic kidney disease (CKD). Despite the improvement of capillary blood flow velocity in retina after pentoxifylline use, no evidence has been provided to prove the protective effect for diabetic retinopathy (DR). Therefore, this study aimed to assess the risk of DR in pentoxifylline users with CKD and diabetes mellitus (DM). Material and methods In this retrospective cohort study, Chang Gung Research Database, which includes the data of patients with CKD and DM from 2003 to 2019, was used. Each calendar year was divided into 4 data units with 3 months each for every patient and every year during the follow-up. The ocular outcomes were new-onset DR, DR-related complications, and vitreoretinal interventions. Results Total 56,439 patients without preexisting DR and 5,039 patients with preexisting DR were included in this study. Exposure to pentoxifylline was associated with elevated risk of new-onset DR (adjusted hazard ratio = 1.24, 95% confidence interval = 1.13–1.36) in patients without preexisting DR. Additionally, exposure to pentoxifylline was associated with elevated risk of DR-related complications and vitreoretinal interventions in patients with or without preexisting DR. Conclusions Exposure to pentoxifylline is associated with elevated risk of DR, regardless of whether patients have preexisting DR.