Medication adherence decreases chance of glaucomatous vision loss
Researchers found that patients who more consistently took their prescribed glaucoma medication were less likely to develop vision loss due to glaucoma.
Study participants were recently diagnosed with open-angle glaucoma and enrolled in 14 centers across the U.S. for the Collaborative Initial Glaucoma Treatment Study. They were randomly chosen to undergo trabeculectomy or receive medication.
The researchers determined eligibility based on elevated IOP, visual field changes and optic disc findings and narrowed the participants they analyzed down to those receiving medication. This left 306 patients in the study, 29 to 76 years old, who attended at least one follow-up visit.
Follow-up visits occurred at 3 months, 6 months and every 6 months afterward for up to 10 years after randomization. Visits involved clinical examination and visual field assessment, measured by mean deviation (MD). Phone interviews gauged quality of life and were scheduled at the same intervals, although visits and interviews were independent and could occur in either order.
Medication adherence for each participant was categorized in four ways: no visits with a reported missed dose of medication, between zero and one-third of visits with a missed dose, between one-third and two-thirds of visits with a missed dose and more than two-thirds of visits with a missed dose.
One hundred forty-two participants (46%) reported never missing a dose, 112 (37%) reported missing a dose at one-third or fewer of the follow-up visits, 31 (10%) reported missing a dose at one-third to two-thirds of their visits, and 21 (6.9%) reported missing a dose at more than two-thirds of their visits.
Over the follow-up period, those who never missed a dose had an estimated loss of visual field of 0.62 dB, patients who reported a missed dose at less than one-third of their visits experienced visual field loss of 1.42 dB, and those who reported missed doses at two-thirds of their visits experienced visual field loss of 2.23 dB, on average.
The authors recognized that because the patients were clinical trial participants, they adhered well to their medication and visits and showed relatively little visual field progression over the course of the study. As a result, their data, “likely underestimates the true magnitude of the association between medication adherence and visual field progression.” – by Kalie VanDewater
Disclosures: Newman-Casey reports no relevant financial disclosures. Please see the study for all other authors’ relevant financial disclosures.