Glaucoma Progression in Treatment-Naïve Patients With Normal Tension Glaucoma With Myopia-Role of Intraocular Pressure.

PRCIS

While myopia has been recognized as a positive prognostic factor for normal tension glaucoma (NTG) progression in the adult population, some myopic NTG eyes exhibited significant progression within 2 years when left untreated, even under low intraocular pressure (IOP).

OBJECTIVE

To determine the natural history and risk factors associated with progressive retinal nerve fiber layer (RNFL) thinning in previously stable, treatment-naïve, patients with NTG with myopia.

METHODS

This study included 111 myopic NTG eyes without IOP-lowering treatment for at least 1 year and without disease progression during the treatment-free period. The RNFL thickness was measured, and a visual field test was performed every 6-12 months for >2 years. Patients with progressive changes were classified as the P(+) group, whereas those without progression were classified as the P(-) group. Cox proportional hazards model assessed risk factors of progression, whereas linear regression determined factors associated with the rate of RNFL thinning.

RESULTS

Progressive change was observed in 25 of the 111 participants [P(+) group, 22.5%]. A family history of glaucoma, higher mean IOP, and maximum IOP during the follow-up were significant factors both for being in the P(+) group and for a faster RNFL thinning. None with a mean IOP <11 mm Hg were in the P(+) group. Davies test identified that 14.2 mm Hg was a significant breakpoint ( P = 0.042), above which the rate of RNFL thinning increased significantly with the mean IOP ( R2 = 0.252, P = 0.034).

CONCLUSIONS

Patients with myopic NTG untreated for IOP, especially those with a family history of glaucoma or higher IOP, are at increased risk of progression. Early treatment initiation is advised for high-risk patients with myopic NTG, even when their condition appears stable.