Compliance with glaucoma medications, as with medications for any type of chronic diseases, is a major risk factor for progression. In the study by Kass et al. (12) using an eyedrop medication monitor, compliance with pilocarpine was found to be very poor. Fifteen percent of patients administered less than one-half of the prescribed doses.
Twenty-five percent of patients missed at least 1 day per month. When interviewed, however, patients reported taking an average of 97% of prescribed doses. In general, compliance with medications decreases with the frequency of dosing and the number of medications. However, even with newer medical therapies with less frequent dosing, compliance continues to be very poor (13). This is further exacerbated by the fact that glaucoma is an asymptomatic disease until the very late stages, and therapy does not result in any subjective improvement in their condition. Other major reasons for noncompliance include medication side effects (both local and systemic) and difficulty administering the medication.
In a patient where target IOP cannot be achieved consistently due to noncompliance, surgery must be seriously considered but only after patient education has been tried. The majority of the reasons sited by patients for noncompliance is not related to social or environmental factors and may be amenable to patient education or modification of medications (13). These include regimen factors (e.g., cost, complexity and side effects), patient factors (lack of knowledge/skill, forgetfulness, lack of motivation, and complexities created by co-morbidities), and medical provider factors (e.g., dissatisfaction with care and lack of communication).
Some situational compliance factors may be difficult to remedy. Patients who live in parts of the world where drops are not available or are prohibitively expensive, or live alone and have difficulty in administering the drops for physical reasons require earlier glaucoma surgery in order to achieve target pressures (14,15). However, caution must be exercised since good compliance with medications is required postoperatively in order to reduce potential surgical complications and enhance the chance of successful surgery.
