The relationship between glaucoma medication adherence, eye drop technique, and visual field defect severity

Objective: The purpose of the study was to examine (1) how patient adherence and eye drop technique were associated with visual field defect severity and (2) how general glaucoma adherence self-efficacy and eye drop technique self-efficacy were related to visual field defect severity. Design: Cross-sectional study conducted at a single private practice site. Participants: Patients using eye drops for their glaucoma. Methods: Subject adherence to glaucoma medications through Medication Events Monitoring System (MEMS) devices were measured, and eye drop instillation technique was assessed by video recording. General glaucoma medication adherence self-efficacy was measured using a 10-item scale, and eye drop technique self-efficacy was measured using a 6-item scale. Multivariate logistic regression was used to analyze the data. Main Outcome Measures: Visual field defect severity. Results: Patients who were less than 80% adherent according to the MEMS devices were significantly more likely to have worse defect severity. Patients with lower scores on the general glaucoma medication adherence self-efficacy scale also were significantly more likely to have worse defect severity. Eye drop technique and eye drop technique self-efficacy were not related significantly to visual field defect severity. Conclusions: Eye care providers need to assess patient adherence and to work with those patients with poor adherence to find ways to improve their ability and self-efficacy in using their glaucoma medications.