Degree of myopia not a risk factor for glaucoma, study finds

MANNHEIM, Germany — For patients with myopia under -8 D, the presence and amount of refractive error may not be a risk factor for glaucoma or for the amount of glaucomatous optic neuropathy, according to a study.

Researchers here with the University Eye Clinic conducted a comparative observational study of 1,444 eyes of 876 patients with primary or secondary open-angle glaucoma. Patients with high myopia (defined as -8 D or higher) were excluded from the study. Main outcome measures were refractive error, neuroretinal rim area, horizontal and vertical cup/disc diameter ratios and visual field loss.

In an interindividual statistical analysis, none of the outcome measures were statistically correlated with refractive error. In an intraindividual comparison, inter-eye differences in refractive error also were not significantly correlated with inter-eye differences in neuroretinal rim area and mean visual field defect. The eye with the higher myopia and the eye with a lower myopic error did not vary significantly in neuroretinal rim area and mean visual field defect.

The study is published in the October issue of American Journal of Ophthalmology.