Medication adherence difficult for many glaucoma patients

September 1, 2007

Patients need to be educated about the importance of glaucoma medication adherence. They should be asked about possible nonadherence and the reasons for it. Such information can guide a targeted plan to overcome treatment barriers.

Key Points

"What we do in treating our glaucoma patients medically can more accurately be considered 'intent to treat.' We prescribe the medication, but patients treat themselves. We need to learn how to talk with our patients to drive them to do a better job," said Dr. Fechtner, professor of ophthalmology and director, glaucoma division, New Jersey Medical School–University of Medicine and Dentistry of New Jersey, Newark.

It is easy to appreciate why patients may not always use glaucoma medications as directed, he noted, considering that glaucoma is a largely asymptomatic disease that requires chronic treatment, sometimes with complex medication regimens that can result in side effects.

Dr. Fechtner cited the landmark study on glaucoma medication adherence reported by Kass et al. more than two decades ago, wherein pilocarpine usage was investigated using an electronic bottle monitor. Although 97% of patients claimed to have used medications as prescribed, results from the monitor showed that medication was used, on average, only 76% of the expected time. Fifteen percent of patients used less than one-half of their drops, and 6% used less than 25% of the expected doses. The data also revealed that compliance rose significantly in the 24 hours preceding the return appointment.

"The investigators analyzed a number of parameters to see if any were predictive of compliance, but none could distinguish adherent patients from their counterparts who were not. It seems the poor adherence cannot be attributed to just the QID dosing schedule of pilocarpine, because similar results were found in a subsequent study of patients using BID timolol," Dr. Fechtner said.

Various issues may create obstacles to adherence. Those obstacles can be categorized into four major domains (social/environmental, medication regimen-related, patient-related, and provider-related) as described in an article by James Tsai, MD, and colleagues [J Glaucoma 2003;12:393-398]. Although knowledge of the relevant problems can aid patient education and problem-solving efforts, however, it still may be difficult to identify the non-adherent individual, particularly if medication use improves immediately before a scheduled visit and the patient's IOP appears to be well-controlled.

Certain strategies can be used to address that issue and enable detection of patients with adherence problems. For example, patients may be asked to name their medication, its appearance, and when it was last refilled. They also should be able to tell what times of day they use their medications and may be asked to demonstrate with a bottle of artificial tears how they instill their drops.

"Getting drops into the eye is not a trivial task for older individuals. It may be that some patients need retraining in the instillation technique," Dr. Fechtner said.

In exploring adherence, the physician also should formulate questions in a framework that gives patients permission to tell the truth.

"Tell the patient you understand there are obstacles to using medications, that most patients have some difficulties and forget a few times a week. Then ask what problems they have and how many times they forgot this week," Dr. Fechtner explained.

Once the obstacles are identified, various strategies can be offered for overcoming the barriers. For example, if patients are forgetting their drops, simple aids are available to alert them that it is time for their dose. Such patients can be told to set an alarm on a clock or watch, or enlist the help of a relative or friend to provide a reminder. Patients who have difficulty with instillation can try a dosing tool, such as a drop guider.

"Often, there are multiple obstacles, and then a multifaceted approach may be needed," Dr. Fechtner said.