Relationship between the number of glaucoma medications, ocular surface disorder, and treatment adherence

Purpose: To determine the relationship of ocular surface disease, the number of glaucoma medications prescribed and its influence on treatment adherence. Methods: In this cross-sectional study, demographic data of patients with glaucoma were collected, and patients completed the ocular surface disease index questionnaire and the glaucoma treatment compliance assessment tool. Ocular surface parameters were assessed by "Keratograph 5M." Patients were stratified into two groups according to the amount of prescribed ocular hypotensive eye drops (Group 1, one or two classes of medications; Group 2, three or four classes) Results: In total, 27 eyes of 27 patients with glaucoma were included: 17 using 1 or 2 topical medications (Group 1) and 10 eyes using 3 or 4 classes (Group 2). For the Keratograph assessment, patients using >= 3 medications had significantly smaller tear meniscus height (0.27 +/- 0.10 vs. 0.43 +/- 0.22; p=0.037). The analysis of Ocular Surface Disease Index questionnaire showed higher scores among the groups using more hypotensive eye drops (18.67 +/- 13.53 vs. 38.82 +/- 19.72; p =0.004). Regarding the glaucoma treatment compliance assessment tool, Group 2 had worse scores in components of forgetfulness (p=0.027) and barriers due to lack of drops (p=0.031). Conclusion: Patients with glaucoma using more hypotensive eye drops had worse tear meniscus height and ocular surface disease index scores than those using fewer topical medications. Patients using three or four drug classes had worse predictors of glaucoma adherence. Despite worse ocular surface disease results, no significant difference in self-reported side effects was found.