Screening practices and risk assessment for maculopathy in pentosan polysulfate users across different exposure levels.

In this population-based cohort study, we investigated screening practices for maculopathy and incidences of specific macular/retinal conditions in pentosan polysulfate (PPS) users and assessed the relationship between these outcomes and drug exposure levels. Using a health claims database that covers approximately 50 million Koreans, we identified 138,593 individuals who were prescribed PPS between 2010 and 2021. For the 133,762 PPS users who initiated therapy between 2012 and 2021, the cumulative PPS dose for each participant was evaluated, and based on their cumulative PPS dose, patients were categorized into the high-risk (≥ 500 g), low-risk (50-500 g), and minimal exposure (< 50 g) groups. We analyzed the performance and methods of these examination methods used between 2018 and 2021 and compared them among cumulative dose groups to determine whether high-risk users underwent maculopathy screening more frequently or appropriately. We assessed the cumulative incidence of overall macular degeneration and maculopathy excluding common macular diseases following PPS therapy initiation. Most PPS users (99.7%) received a cumulative PPS dose < 500 g and the high- and low-risk groups comprised 445 (0.3%) and 22,185 (16.6%) patients, respectively. During the study period, monitoring examinations were conducted in 52.6% and 49.4% of high- and low-risk patients, respectively, revealing no significant difference between the two groups (P = 0.156). No significant differences were observed in the annual percentages of patients receiving ophthalmic examinations between the high- and low-risk groups (all P > 0.05). The cumulative incidences of overall macular degeneration and maculopathy excluding common macular diseases in high-risk users were 19.3% and 9.0%, respectively, which were significantly different from those of low-risk users (both P < 0.001). Multivariate Cox regression analysis revealed significantly higher risks of maculopathy excluding common macular diseases in the low- (Hazard ratio [HR] of 1.55 [95% CI 1.13-2.12]) and high-risk groups (HR of 1.66 [95% CI 1.22-2.27]) compared to the minimal exposure group. Our findings suggest a need for increased emphasis on PPS maculopathy screening in high-risk patients, highlighting raising awareness regarding exposure-dependent risks and the establishment of screening guidelines.