Abstract
Purpose:
To evaluate how patients identify their topical glaucoma medications and what factors influence level of adherence to prescribed regimens.
Methods:
A cross-sectional survey of glaucoma patients using topical glaucoma therapy at the University of Colorado Eye Center was conducted. The survey was completed after regularly scheduled clinic visits. Primary outcome measures included accurate identification of medications and their bottle characteristics as well as self reported adherence. Survey responses were compiled and then analyzed using descriptive statistics.
Results:
A total of 126 patients (38% male) completed the survey with an average age of 69.8 +/- 10.6 years and the majority of patients were on monotherapy (57.1%). Patients were able to identify significantly more medication cap colors (84.8%) than medication names (71.4%, p=0.0024). The number of medications used did not correlate to the number of correctly identified medication names or cap colors (p=0.66 & 0.48, respectively). Of patients taking more than one medication, cap color was identified by 64.8% and reading the name on the bottle was identified by 18.5% as important factors for distinguishing bottles. Of the patients identifying cap color as important for distinguishing medications, only 80% correctly identified all cap colors, but 94.3% correctly identified all or all but one of their colors (sufficient for accurate differentiation). Excellent adherence (taking >95% of prescribed doses) was reported by 73.6% of patients. Patients taking more than one glaucoma medication had a significantly more adherent distribution than patients taking only one medication (p=0.032). Adherence to prostaglandin analogs was significantly greater than adherence to carbonic anhydrase inhibitors (96.8% & 92.5% respectively, p=0.031). Age greater than 70 years was associated with better adherence, although this did not reach statistical significance (p=0.070). Gender, cost, and duration of use were not significantly correlated with adherence.
Conclusions:
Glaucoma patients frequently utilize bottle cap color as their method of glaucoma medication identification. More than 1 in 4 patients fail to achieve excellent adherence to prescribed regimens. By understanding factors associated with adherence, such as number of medications used, class of medication, and age, there is an opportunity to focus efforts to improve glaucoma treatment and education.