Determinants of patients' adherence to glaucoma topical therapy among Nigerian adults

Context: Glaucoma is a leading cause of irreversible blindness globally. Among its risk factors only raised intraocular pressure is modifiable with capacity to reduce the progression of glaucoma. Adherence to intraocular pressure lowering medications is a key factor in the medical management of glaucoma. Aims: The aim of this study was to determine adherence to glaucoma topical medications and its determinants among patients. Settings and Design: This was a comparative longitudinal hospital-based study. Subjects and Methods: Ninety-six primary open-angle glaucoma patients were randomly grouped into A and B and surveyed for topical medication adherence and its determinants. All participants were counseled on medication adherence, and given dosing time schedule. Participants in Group B/reliable household members were reminded through phone calls to use their medications. Adherence level, its determinants, effect of adherence on intraocular pressure (IOP), and central visual field defect progression were assessed at baseline, 90 days, and 180 days. Statistical Analysis Used: Data normality was tested using Shapiro–Wilk test. Results were presented in frequency tables, figures, and charts. Chi-square test, Fisher's exact test, and odds ratio were used to evaluate the associations between variables where applicable. Multivariate logistic regression was employed to determine factors predicting adherence. The level of statistical significance was set at P < 0.05. Results: At baseline, 35.4% of the participants were adherent to medications, with intervention at 90 days (81.2%, A, and 79.2%, B) and at 180 days (75.0%, A, and 83.3%, B) of the participants who adhered to medications. Predictors of adherence to medications were age below 40 years (adjusted odd ratio [AOR] = 5.10; 95% confidence interval [CI], 1.18–21.82; P = 0.029) and the presence of comorbidities (AOR = 5.41; 95% CI, 1.64–17.86; P = 0.009). There was no significant difference in the mean IOP between the two groups at baseline, 90 days, and 180 days. Conclusions: There was an improvement in medication adherence following counseling. Younger age and comorbidities were notable adherence determinants.