A study which appeared in the clinical journal of Ophthalmology concludes that farsightedness appears to be associated with a five-year risk of ocular hypertension, and nearsightedness is associated with a significantly increased prevalence of glaucoma, in Caucasians. The study was conducted with nearly 5000 participants, aged between 43 to 84, who received baseline assessments of refractive error (nearsightedness and farsightedness), intraocular pressure and glaucoma, and five-year follow-up measurements of intraocular pressure and ocular hypertension.
Researchers found that farsighted participants were 40 percent more likely to have incident ocular hypertension than those without refractive error. Incident ocular hypertension is high intraocular pressure with no apparent damage to the optic nerve and visual field defects that characterize glaucoma, though glaucoma may develop with time. The study also found nearsighted participants were 60 percent more likely to have glaucoma than those without refractive error. The researchers who noted that farsightedness has been associated with primary angle-closure glaucoma, say that the shallower front chamber of the eye may predispose a person to higher intraocular pressure. They also say it is possible farsightedness "may simply be a marker for biologic aging". However, they added that they do not have adequate explanation for the association and that further research is needed.
Andrew Iwach, M.D. concluded that people need to get comprehensive, dilated eye exams to determine if they are at risk for glaucoma or ocular hypertension, what their exam frequency should be, and whether they require individualized management plans, instead of just refractive eye exams for glasses or contacts.