Easy Does It?

When it comes to ocular hypertension, conventional wisdom points to the need to act fast to protect vision. But recent findings suggest otherwise. The Ocular Hypertension Treatment Study (funded by the National Eye Institute and led by researchers at Washington University School of Medicine, USA) recruited 1,600 patients who were at moderate to high risk for glaucoma because of elevated eye pressure. Half received daily treatment with eye drops, while the other half were observed without treatment. After seven years, when the treatment had been shown to be highly effective, patients in both groups were given drops. The team showed that preventive treatment reduced the incidence of glaucoma by 50 to 60 percent after five to seven years, but even with that substantial decrease, the total number of people who developed glaucoma remained relatively low, with only 25 percent going on to develop vision loss from glaucoma in at least one eye – much fewer than initially expected.

The study suggests physicians can delay pressure-lowering treatment until early damage is detected, without adversely affecting long-term outcomes. The next step? Determining which patients would benefit from preventative treatment.

Michael A. Kass, the Bernard Becker Professor of Ophthalmology and Visual Sciences and lead author of the study, helped establish the five key risk factors: a patient’s age, level of intraocular pressure, thickness of the cornea, a measurement of the appearance of the optic nerve head, and another measurement derived from standard visual field tests. “The five factors were determined using a multivariable risk model where they were entered one at a time to see if they improved the predictive power, with all factors weighted to one standard deviation,” explains Kass.

While Kass does not consider a delay in pressure-lowering treatment risky, a high-risk person or a person who is concerned can start treatment before damage is detected. “This should cause the clinician and the patient to discuss the situation taking into consideration patient age, health status, life expectancy and personal preference.”