The elevated risk of sight-threatening cataract in diabetes with retinopathy: a cohort study

Abstract

Background To survey the effect of diabetic retinopathy (DR) on the development of sight-threatening cataract via National Health Insurance Research Database of Taiwan.Methods Patients diagnosed with diabetes mellitus (DM) and DR were enrolled in the study group. The age and gender-matched DM individuals without DR and patients without DM served as the DM control group and non-DM control group, both with 1:4 ratios. The outcome was set as the performance of cataract surgery. Cox proportional hazard regression was used to calculate the adjusted hazard ratio (aHR) of DR with considering multiple factors of cataract formation.Results A total of 3,297 DR patients, 13,188 DM control patients and 13,188 non-DM controls were enrolled. There were 919 events (27.87 percent) of sight-threatening cataract in the study group while another 1,108 events (8.40 percent) in the DM control group and 957 events (7.26 percent) in the non-DM control group. After multivariable analysis, the study group showed a higher aHR of cataract surgery (2.93, 95% CI: 2.60-3.30) and a higher cumulative probability of cataract surgery compared to both the DM control and non-DM control groups (both Log rank P<0.001). Besides, both the proliferative DR (3.90, 95% CI: 3.42-4.45) and non-proliferative DR (2.35, 95% CI: 2.08-2.65) subgroups showed a higher aHR of cataract surgery than the DM control group.Conclusion The presence of DR will increase the risk for development of sight-threatening cataract that surgery is warranted, and the effect is prominent in both the proliferative DR and non-proliferative DR.