Objective: The aim of this study was to evaluate the potential benefit of intraocular pressure (IOP) reduction in normal tension glaucoma (NTG) Asian adult patients in South Korea.

Methods: This was a retrospective, multicenter analysis of 166 NTG Asian adult patients in South Korea. The patient population consisted of Korean patients with NTG with at least 5 years of records available for evaluation. Patients all had typical glaucomatous optic-disc and/or visual-field changes but had never had a recorded IOP >21 mmHg.

Results: Overall, 48 (29%) patients were progressed and 116 (71%) were stable over the follow-up period. Of patients with IOPs or=15 mmHg (27/73) 37% progressed (P = 0.041). The mean IOP for the stable group was 14.0 +/- 1.8 mmHg, whereas with the progressed group the average mean IOP was 14.4 +/- 1.6 mmHg (P = 0.20). The mean peak IOP was 17.4 +/- 2.2 mmHg in the stable group and 17.8 +/- 2.0 mmHg in the progressed group (P = 0.26). Multivariate linear regression analysis did not any identify independent risk factors for progression, including age, gender, or mean and peak IOP.

Conclusions: This study provides initial evidence that Korean patients with normal-tension glaucoma, treated to lower IOPs, may have a decreased incidence of progression over 5 years than those patients with higher IOPs. More research is required to confirm this finding.