Ocular Surface Disease and Glaucoma: How to Evaluate Impact on Quality of Life.

Abstract Purpose: To record signs and symptoms of ocular surface disease (OSD) in patients treated with Intra Ocular Pressure (IOP)-lowering medications; to evaluate relation between signs and symptoms; and to identify how to diagnose and follow OSD and its impact on the quality of life in such patients. Methods: A prospective observational study enrolled consecutive topically treated open-angle glaucoma or ocular hypertension patients: patients presenting systemic or ocular conditions that could interfere with ocular surface status were excluded. Enrolled patients underwent a complete ophthalmic examination comprehensive of evaluation of tear film break-up time (TF-BUT) and fluorescein corneal staining (keratitis punctatae) and completed the Italian version of both the National Eye Institute-Visual Function Questionnaire (NEI-VFQ) 25 and the Glaucoma Symptom Scale (GSS) questionnaires. Results: 233 patients adhered to a study protocol. Punctatae keratitis was detected in 70 (30\%) eyes; abnormal TF-BUT in 67 (28.8\%) patients: 97 patients (42.1\%) presented an OSD. The abnormal values were gender-independent, keratitis was statistically related to age (P=0.01) and number of instillations/die (P=0.0007). TF-BUT was related to the IOP value (P<0.0001). The NEI ocular pain subscale was statistically related to TF-BUT (P=0.017); GSS was both related to TF-BUT and punctatae keratitis (P<0.00001). Conclusions: Many patients present an OSD related to therapy, and this affects their quality of life. The use of fixed combinations to reduce surface exposition and of benzalkonium chloride-free formulations should be encouraged to reduce and contain the onset or worsening of this secondary condition in glaucoma patients. The GSS has shown a good relation to signs and should be routinely used to evaluate the impact of OSD on the quality of life.