ABSTRACT
OBJECTIVE: To evaluate the association between the intensity and duration of glaucoma topical therapy and severity of signs and symptoms of ocular surface disease (OSD). DESIGN: Single-site, prospective, controlled, cross-sectional study. PARTICIPANTS: Sixty-one patients with no diagnosis of or previous treatment for OSD were identified. METHODS: Patients were assigned to 2 groups: the glaucoma group with 31 patients diagnosed with primary open-angle glaucoma and using at least 1 topical intraocular pressure (IOP)-lowering medication and the control group including 30 patients with no diagnosis of glaucoma or history of topical therapy usage. The right eye of each patient was arbitrarily chosen. Each patient completed an Ocular Surface Disease Index (OSDI) questionnaire and underwent evaluation of the ocular surface by conjunctival and corneal lissamine green (LG) staining and tear breakup time (TBUT). The intensity index (drops/wk × therapy duration in years) was calculated to quantify the topical therapy. RESULTS: OSDI scores of the glaucoma group correlated to the intensity index (r = 0.46, CI 0.13-0.69). The glaucoma group had a higher mean OSDI score than the control group (18.97 ± 9.5 versus 6.25 ± 5.7, p = 5.85E-08). Abnormal TBUT and LG staining scores were prevalent in the glaucoma group compared with the control group (68% vs 17%, p = 0.000078; 65% vs 3%, p = 2.9E-07). CONCLUSIONS: Patients on glaucoma therapy have a greater prevalence of OSD symptoms, and their intensity index correlates to the OSDI score. The intensity index reflects quantitatively the amount of treatment and can be further validated in future studies as a predicting tool for OSD development.
