Non‐compliance in glaucoma treatment: a Hong Kong perspective

Editor, W e read with interest the recent article by Chawla et al. (2007) on the issue of non-compliance in glaucoma eyedrop treatment in the UK. Non-compliance is a particularly important issue in glaucoma because the management of this disease requires the patient’s longterm adherence to the medication regimen if a longterm neuroprotective effect is to be achieved. In Hong Kong, we conducted a similar prospective, crosssectional study of compliance rates in glaucoma patients between September 2001 and December 2002 (Pong & Lai 2005). In this study, glaucoma patients on treatment were recruited through interviews using pre-designed questionnaires. Information on demographics, socioeconomic and educational levels, awareness of their eye diseases, frequency of missed doses, reasons for omitting doses, adverse effects and concurrent medical diseases was obtained. We recruited 71 patients (mean age 65.3 ± 12.8 years) for the study. Forty-five patients (63.4%) admitted having missed doses in the period between the last and present follow-up visits; 35 of these patients (49.3% of the sample population) reported missing less than five doses in 1 week and nine patients (12.7%) admitted missing more than five doses in 1 week. Patients on monotherapy had a higher rate of non-compliance than patients on two or more eyedrops (65% versus 59%). Patients who had been started on glaucoma treatment for the first time (n = 17, non-compliance rate = 59%) had a lower non-compliance rate than those who were longterm users (n = 54, non-compliance rate = 64.8%). The majority of our patients (67.6%) were not aware of the nature of their diseases. There were no significant differences in terms of non-compliance with respect to age, sex, educational level, awareness of eye diseases, first-time medication or number of medications prescribed. The main reasons for noncompliance in this study included unexpected side-effects and misunderstanding of the instructions. The non-compliance rate in our study was much higher than those found by Chawla et al. (2007) and other studies (Patel & Spaeth 1995; Taylor et al. 2002). We agree with Chawla et al. (2007) that lack of understanding about the side-effects of eyedrops is one of the main causes of non-compliance. However, in our study, misunderstanding of instructions also represented a main factor. Although medications used in our hospital system are labelled by computer, patients with poor vision or low educational levels may still not understand the instructions. Furthermore, our patients may have different behavioural responses to diseases and medical treatments based on their cultural beliefs. We believe a different cultural perspective may also contribute to the high non-compliance rates in Hong Kong. By contrast, difficulty in using eyedrops was not found to be an issue in our study population. We agree with the authors that, in order to improve compliance, diagnoses, treatment objectives and adverse effects profiles should be fully explained to patients, preferably with the help of pamphlets and videos. Greater patient participation in intraocular pressure monitoring can improve both disease awareness and compliance.