The Association between a Pharmacy-Based Estimate of Medication Adherence and Surgical and Laser Treatments in Glaucoma Patients

Purpose: To investigate medication adherence in glaucoma and glaucoma suspect patients and explore its relationship with nonpharmacological treatments, including traditional surgery, minimally invasive glaucoma surgery (MIGS), and laser treatment. Design: A retrospective cohort study. Subjects: A total of 4480 medically treated glaucoma and glaucoma suspect eyes from 3668 patients who presented to the Wilmer Eye Institute between November 2015 and March 2025, with at least 1 visual field (VF), 1 OCT scan, 1 clinic visit, and corresponding pharmacy claims data for topical intraocular pressure-lowering medications. Methods: Patient procedures were categorized by intervention type based on Current Procedural Terminology codes. Time between the first VF, OCT, or clinic visit and the first laser or surgical procedure was determined. Medication adherence was estimated using the proportion of days covered (PDC), calculated using prescription and dispensing data from electronic medical records and pharmacy claims data. Multivariable Cox regressions assessed the association between PDC and the likelihood of traditional surgery, laser treatment, or MIGS. Subgroup analysis of baseline glaucoma severity was also conducted. Main Outcome Measures: Type and timing of initial nonmedical interventions. Results: The average medication adherence measured by PDC was 56.1% (standard deviation: 23.6). Of the 4480 eyes studied, 1724 (38.5%) eyes received medical treatment exclusively, while 2756 (61.5%) underwent at least 1 procedure. Among those that had a procedure, 1396 (31.2%) underwent laser treatment, 507 (11.3%) underwent MIGS, and 853 (19.0%) underwent traditional surgery. A 10% lower PDC was associated with an increased likelihood of laser treatment (hazard ratio [HR]: 1.05, 95% confidence interval [CI]: 1.02–1.07), MIGS (HR: 1.07, 95% CI: 1.03–1.11), and traditional surgery (HR: 1.15, 95% CI: 1.11–1.18). In suspect and mild baseline glaucoma eyes, lower PDC was associated with laser treatment (HR: 1.12, 1.04), MIGS (HR: 1.16, 1.07), and traditional surgery (HR: 1.14, 1.22). In moderate and severe baseline glaucoma eyes, lower PDC was associated with traditional surgery only (HR: 1.12, 1.09). Conclusions: Lower PDC was associated with an increased likelihood of undergoing any nonmedical intervention. In eyes with severe baseline disease, lower PDC correlated with a higher likelihood of traditional glaucoma surgery but not laser or MIGS procedures. Financial Disclosure(s): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.