An image through the eyes of a patient with age-related macular degeneration. Photo credit: National Eye Institute, National Institutes of Health.
By Rebecca Salowe
Scheie Vision Summer 2020
In a recent publication in JAMA Ophthalmology, Brian VanderBeek, MD, MPH, Assistant Professor of Ophthalmology, showed that missing one ophthalmology appointment is associated with decreased visual acuity for patients with neovascular age-related macular degeneration (AMD).
AMD is the leading cause of permanent vision loss in individuals over age 50, with 1.8 million Americans affected as of 2020. Approximately 10% of these patients progress to neovascular (or “wet”) AMD, which is characterized by the abnormal growth of new blood vessels under the macula. If untreated, bleeding, leaking, or scarring from these blood vessels can lead to irreversible loss of central, sharp vision.
Though there is no cure for wet AMD, this condition can be managed with anti-vascular endothelial growth factor (VEGF) agents that are injected into the eye. These agents bind and inhibit VEGF, a protein that stimulates the formation of blood vessels. However, patients must receive frequent—often monthly—injections from an ophthalmologist for continued therapeutic benefit.
While visit adherence is important for all diseases, it is absolutely essential for neovascular AMD, as the treatment involves a physical injection. Prescriptions cannot be filled over the phone if an appointment is missed.
However, studies show that the nonadherence or missed appointments among this patient population can range from 18% to 57%. Possible reasons for these high rates include the older age of patients, medical comorbidities, difficulty with transportation, fear of eye injections, or lack of disease awareness.
Dr. VanderBeek sought to examine how visit adherence affects visual outcomes in individuals with neovascular AMD. Data from 1178 patients in the Comparison of Age-Related Macular Degeneration Treatments Trials (CATT), which compared the safety and efficacy of two AMD drugs, was used for this study.
Over a two-year period, each patient was required to visit an ophthalmologist every four weeks, for a total of 26 visits. The visits often, but not always, involved an injection. Dr. VanderBeek and his team analyzed four metrics of adherence and compared these metrics to patient outcomes on final vision tests.
The mean number of missed visits among patients was 2.4. For all four metrics, the patients with the best adherence to scheduled visits had better visual outcomes. Missing just one visit was associated with a visual acuity letter score decline of 0.7.
Interestingly, the same results were seen even when controlling for the number of injections received by each patient. These results suggest that visits to an ophthalmologist for neovascular AMD are important not only to receive injections, but also to monitor disease activity and modify treatment plans.
“While it wasn’t surprising that a link exists with showing up for scheduled visits, it was surprising to see that even a single missed visit could impact vision,” said Dr. VanderBeek.
These results highlight the importance of ensuring visit adherence among this patient population. Ophthalmologists can emphasize the importance of the frequency of visits, not just injections, as being associated with the best possible visual outcomes.
Future studies can focus on how to create policies that help patients overcome any social, financial, or educational barriers to attending appointments.