Nationwide Screening Practices of Tamoxifen Retinopathy in South Korea: a Population-Based Cohort Study

Abstract

Abstract In this population-based cohort study, we investigated the nationwide screening practices and trends in tamoxifen retinopathy in South Korea using national health insurance claims data. A total of 43,848 patients who started tamoxifen therapy between 2015 and 2020 and had no prior ophthalmic diseases or other conditions requiring screening for retinopathy were included. The annual numbers of tamoxifen users and new initiators of tamoxifen therapy were assessed. The screening examinations were separated into baseline (first ophthalmic examination after tamoxifen administration) and subsequent monitoring examinations. The timing and modalities for the baseline and subsequent monitoring examinations performed between 2015 and 2021 were assessed in tamoxifen users. The annual number of tamoxifen users increased over the study period from 54,056 in 2015 to 81,720 in 2021. The number of patients who underwent ophthalmic examination after tamoxifen administration was 8,961 (20.4%). Baseline screening was performed in 6.5% of patients within 1 year of use, and subsequent monitoring was performed in 27.8% of patients who underwent baseline screening. The mean number of monitoring examinations per year was 0.68 ± 0.45. Funduscopy/fundus photography was most commonly performed for baseline screening and subsequent monitoring (99.0% and 98.6%, respectively), while optical coherence tomography was performed only in 21.9% and 29.6% of baseline and monitoring examinations, respectively. Although the annual percentage of patients receiving a baseline examination within 1 year gradually increased over time, those with subsequent monitoring performed within 1 year were similar over the study period. Our finding, appropriate screening in a small proportion of patients receiving tamoxifen, suggests the need to promote awareness among healthcare professionals and develop a standardized approach for screening tamoxifen retinopathy.