Impact of mono‐ or multitherapy on ocular surface health and quality of life after 5 years of follow‐up in the Glaucoma Intensive Treatment Study (GITS)

AIM: To evaluate the impact of initial mono- versus multitherapy on the ocular surface and related quality of life after 5 years follow-up in the Glaucoma Intensive Treatment Study (GITS). METHOD: The study included patients with primary open-angle glaucoma and pseudoexfoliation glaucoma who completed 5-year follow-up in GITS. Assessment of ocular surface disease (OSD) symptoms was done using a Swedish Translation of the OSD Index (OSDI). Signs of OSD were assessed with tear break-up time (BUT), Schirmer I test and staining using Lissamine green. Rasch analysis was used to analyse OSDI results. RESULTS: Data on OSD symptoms were available at 5 years in 90% (219/242) of all participants initially included in GITS. Subjective or objective OSD findings did not differ significantly between mono- and multitherapy. More than 90% of patients in both arms reported no or little subjective ocular surface problems and showed no or minimal staining with Lissamine green at the 60-month visit. Furthermore, 46% had normal BUT and 60% normal Schirmer tests. Use of preservative-free drops or need for additive lubricating tear drops did not differ between the arms. CONCLUSION: We found no differences in objective or subjective impact on ocular surface between the two randomization arms. However, a subgroup of glaucoma patients had more severe OSD irrespective of the amount of topical glaucoma treatment received, and this should be considered when choosing glaucoma therapy treatment in this subgroup by considering laser treatment or non-preserved eye drops.