Compliance, Persistence and Adherence: Glaucoma Therapy – The Nasty Secrets

HA Quigley, D Friedman and S Hahn

Abstract:
Glaucoma is a highly prevalent, asymptomatic disease that is often treated with the prescription of chronic eye drop therapy. As with other chronic medical conditions, the cooperation of patients with prescribed medical regimens is less than ideal. This course will outline and discuss issues related to the effectiveness of therapy and its improvement, using both glaucoma-specific and general medical information. The issues most immediately relevant to explaining poor patient cooperation with therapy, include: lack of symptoms, slow progressive change in visual function, delay in loss of quality of life until late in the disease, poor patient understanding of the disorder, lack of adequate physician educational efforts, cost of medication, frequent dosage, and multi-drug regimens (Ref. http://www.glaucom.com/Meetings/7-3/AIGS_CoopThera.php)

Definitions:

Compliance: Use of medication in accordance with prescribed regimen.

Persistence: Continuous use of a prescribed medication with no lapses. This is the most stringent definition. There is building use of a less stringent terminology in which some more latitude is allowed in refill lapse before calling the patient non-persistent. However, this would be arbitrary and dependent upon assumptions of how long it takes to use up certain volumes of eye drops.

Adherence: Continued use of a prescribed medication at any time point after initial prescription. In essence, this is a very relaxed version of persistence, for which a patient could lapse for a considerable period (months), but still be 'adhering' if a refill of eye drops occurred at some later time.

1. The problem (Harry Quigley)

Patients identified as having a need for treatment for glaucoma do not continue to take eye drop medications as prescribed. Many not only stop taking drops altogether, but drop out of care. The problems of case identification, loss to follow-up, inadequate attention to preferred practice patterns, and the costs/inequities of the health care system are all factors that are contributing to more glaucoma blindness.

2. There are similarities in other specialties of medicine (Steve Hahn)

The failure of persons to take prescribed medications in other, systemic conditions is similar to that in glaucoma treatment in many ways. While eye drop taking has unique aspects of delivery, the general principles of non-cooperation and even its general magnitude suggest that common themes and solutions may be applicable across medicine.

3. Recent findings in what causes poor cooperation
(David Friedman)

Studies of large insurance databases lead to a number of conclusions about how many persons take drops at the prescribed intervals. Furthermore, by interviewing subsets of these patients and their physicians, as well as by performing chart reviews of their data, a clearer picture emerges of the risk factors for lack of cooperation.

4. Known and potential intervention strategies to improve cooperation (Steve Hahn)

By using the more recent data from ophthalmology and by incorporating ideas already tested in other fields, suggestions can be made as to how best to identify the more non-cooperative patients and how to improve the rate of cooperation by practical approaches.

5. The future (Harry Quigley)

Much information is still needed to improve cooperation with therapy. Research projects need effective outcome measurement devices, such as electronic monitors on eye drop bottles. Interventions that sound good in principle need to be tested for practical value.