Electronic monitoring to assess adherence with once-daily glaucoma medications and risk factors for nonadherence: the automated dosing reminder study.

IMPORTANCE Adherence with topical glaucoma medications is low in some patients. To identify these patients, we need more information on risk factors for nonadherence. OBJECTIVE To assess adherence with once-daily glaucoma medication. DESIGN, SETTING, AND PARTICIPANTS Prospective cohort study involving patients who were recruited from a university-based glaucoma clinic and treated with once-daily prostaglandin eyedrops. Baseline characteristics were recorded, and each patient was provided a medication bottle to hold his or her eyedrop bottle throughout the study. An electronic cap recorded each time the larger bottle holding the eyedrops was opened. Participants were administered standardized tests of depression and mental status and answered questions about their health and their attitudes toward medication adherence. They used the electronic monitors for 3 months, during which their adherence with medications was assessed. MAIN OUTCOMES AND MEASURES Adherence with daily glaucoma medication and factors associated with poor adherence. RESULTS Of the 491 participants enrolled, 407 (82.9%) successfully completed the 3-month adherence assessment. Of this group, 337 (82.8%) took their medication correctly on at least 75% of days and were deemed adherent. Compared with this adherent group, the 70 participants (17.2%) who were nonadherent were slightly younger, were more likely to be of African descent, took medications for a shorter time, had a lower level of educational attainment, and had worse scores on mental status and depression scales (P < .05 for all). Nonadherent participants were less likely to be able to name their glaucoma medications, reported a lower estimate of adherence, and were more likely to admit some missed doses over the past 2 weeks or in general (P < .05 for all). Those who were nonadherent were also less likely to agree that remembering their eyedrops is easy, more likely to strongly agree with the statement that eyedrops can cause problems, and less likely to agree that they followed physicians' orders. CONCLUSIONS AND RELEVANCE Electronic monitoring of patient adherence documented that a sizable number of patients with glaucoma do not take their medications as prescribed. Factors were identified that may prove useful in targeting those nonadherent patients for interventions.