The Ocular Hypertension Treatment Study (OHTS) addressed two primary issues: is early treatment safe and effective to treat patients with ocular hypertension and what are the baseline demographic and clinical factors that might be predictive of which patients will develop glaucoma.
- Fort Lauderdale, FL - The Ocular Hypertension Treatment Study (OHTS) addressed two primary issues: is early treatment safe and effective to treat patients with ocular hypertension and what are the baseline demographic and clinical factors that might be predictive of which patients will develop glaucoma.
Michael Kass, MD, of Washington University, St. Louis, discussed the risk factors for the development of glaucoma that were studied in the 1,636 OHTS patients. The primary goal of the study was to reduce the intraocular pressure (IOP) by 20%.
Univariate analysis pinpointed age, African-American origin, male gender, heart disease, IOP, central corneal thickness, pattern standard deviation (PSD), and the cup-to-disc ratio; multivariate analysis identified age, intraocular pressure, central corneal thickness, PSD, and cup to disc ratio. Male gender, heart disease, and myopia are borderline risk factors that need further study, according to Dr. Kass.
When the corneal thickness and IOP were analyzed to determine if the risk factors can separate individuals at high and low risk of developing glaucoma, the investigators found that by breaking the patients into three groups based on the severity of the parameter analyzed, patients with high and low risk of developing glaucoma can be identified. "This may allow us to make intelligent choices about treatment," Dr. Kass said.
A shortcoming of the study is that potentially important factors such as the diurnal IOP, pseudoexfoliation/pigment dispersion, decreased outflow facility, and the nerve fiber layer appearance were not evaluated.
"Our models should improve with more understanding of genetic factors, quantitative measurement of the disc or the nerve fiber layer, and improvements in various psychophysical tests," he said at the annual meeting of the Association for Research in Vision and Ophthalmology.
"Early treatment can decrease the incidence of primary open-angle glaucoma. Risk factors can be assessed relatively simply in the office to determine high and low risk in a patient. However, just because treatment does work, this does not mean that all patients with elevated IOP should be treated. The clinician has the option to offer treatment to those individuals with ocular hypertension," Dr. Kass concluded.