Motivational interviewing or reminders for glaucoma medication adherence: Results of a multi-site randomised controlled trial

Objective: Nonadherence reduces glaucoma treatment efficacy. Motivational interviewing (MI) is a well-studied adherence intervention, but has not been tested in glaucoma. Reminder interventions also may improve adherence.Design: 201 patients with glaucoma or ocular hypertension were urn-randomised to receive MI delivered by an ophthalmic technician (OT), usual care or a minimal behavioural intervention (reminder calls).Main Outcome Measures: Outcomes included electronic monitoring with Medication Event Monitoring System (MEMS) bottles, two self-report adherence measures, patient satisfaction and clinical outcomes. Multilevel modelling was used to test differences in MEMS results by group over time; ANCOVA was used to compare groups on other measures.Results: Reminder calls increased adherence compared to usual care based on MEMS, p=.005, and self-report, p=.04. MI had a nonsignificant effect but produced higher satisfaction than reminder calls, p=.007. Treatment fidelity was high on most measures, with observable differences in behaviour between groups. All groups had high baseline adherence that limited opportunities for change.Conclusion: Reminder calls, but not MI, led to better adherence than usual care. Although a large literature supports MI, reminder calls might be a cost-effective intervention for patients with high baseline adherence. Replication is needed with less adherent participants.