Abstract
Objectives
To evaluate the association between cataract surgery and the incidence and progression of diabetic retinopathy (DR) in a population-based cohort of patients with diabetes.
Design
A nationwide population-based retrospective cohort study.
Setting
A nationwide administrative claims database in Taiwan covering more than 99% of the population, with longitudinal follow-up from 2010 to 2021.
Participants
Adult patients (≥20 years) with diabetes mellitus and cataract were identified. Patients with prior cataract surgery before the first recorded cataract diagnosis were excluded. A total of 15 360 patients who underwent first-time cataract surgery and 15 846 patients without surgery were included. After two-stage matching (1:2 age-matching and sex-matching followed by 1:1 propensity score matching), 7837 matched pairs were analysed.
Interventions
Not applicable.
Primary and secondary outcome measures
The primary outcomes were (1) incident DR and (2) DR progression within 6 months and 1 year after the index date. Incident DR was defined as new-onset non-proliferative DR (NPDR) or proliferative DR (PDR). DR progression was defined as transition from no DR to NPDR/PDR or from NPDR to PDR. Outcomes were identified using diagnostic codes recorded at least twice in outpatient visits or once during hospitalisation.
Results
Cataract surgery was associated with higher risks of both incident DR and DR progression within 1 year. In the 1:2 matched cohort, the adjusted ORs were 3.40 (95% CI 2.65 to 4.36) for incident DR and 3.11 (95% CI 2.47 to 3.92) for DR progression. Similar findings were observed in the 1:1 propensity score-matched analysis. Absolute event rates at 1 year showed DR progression in approximately 3.1% of patients undergoing surgery compared with 1% in the non-surgical group. Increased risk was also associated with more intensive antidiabetic treatment.
Conclusion
Cataract surgery in patients with diabetes was associated with an increased risk of incident DR and disease progression, particularly within the first postoperative year. These findings support the consideration of cataract surgery as a clinically relevant risk window for enhanced retinal monitoring. Incorporating surgical history into DR risk stratification and screening strategies may improve early detection and inform postoperative care pathways.