The Impact of PCSK9 Inhibitors on Development of Retinal Vascular Occlusions.
PURPOSE: PCSK9 inhibitors (PCSK9i) are a newer class of lipid-lowering drug that may be effective at lowering risk for retinal artery occlusion (RAO) and retinal vein occlusion (RVO). This study aims to investigate the relationship between PCSK9i use and retinal vascular occlusion among patients with hyperlipidemia. DESIGN: Retrospective, comparative clinical cohort study SUBJECTS, PARTICIPANTS, AND/OR CONTROLS: Patients with hyperlipidemia, defined as serum low-density lipoprotein level of ≥130 mg/dL and total cholesterol level of ≥220 mg/dL, prescribed a lipid-lowering medication were identified. Patients prescribed a PCSK9i were included in the study group and compared with control patients prescribed any other type of lipid-lowering drug. METHODS: This study was conducted using electronic health record data from health organizations in the United States through the TrinetX platform. Propensity score matching was completed based on relevant patient demographics, comorbidities, and laboratory values. Comparison of main outcomes between the PCSK9i and non-PCSK9i groups was performed using measures of association analysis to determine risk ratio (RR) with 95% CI. MAIN OUTCOME MEASURES: The outcomes measured consisted of occurrence of retinal vascular occlusion, RAO, RVO, central RAO, and central RVO at 3-year, 5-year, and 7-year time points. RESULTS: After propensity score matching, a total of 12,960 patients were included in each cohort. The analysis revealed that the PCSK9i cohort had a significantly lower risk for development of retinal vascular occlusions at multiple points, including 3-year (RR = 0.56, CI = 0.39-0.79), 5-year (RR = 0.50, CI = 0.37-0.67), and 7-year (RR = 0.46, CI 0.35-0.61) time points. This lower risk was also found in the PCSK9i group for an outcome of RVO at 5 years (RR = 0.50, CI = 0.34-0.73) and 7 years (RR = 0.47, CI = 0.33-0.67). For occurrence of RAOs (RR = 0.47, CI = 0.30-0.76) and central RVO (RR = 0.46, CI = 0.29-0.74) separately, the PCSK9i cohort had a lower risk at 7 years. CONCLUSION: These findings suggest that PCSK9i may reduce the risk of retinal vascular occlusion compared with other classes of lipid-lowering medications.