Canadian glaucoma study: 2. Risk factors for the progression of open-angle glaucoma

Objective: To determine systemic and ocular risk factors for visual field progression in open-angle glaucoma. Methods: In the Canadian Glaucoma Study, a multicenter prospective longitudinal study of 258 patients (131 men and 127 women; median age, 65.0 years), baseline systemic measures included assessment of peripheral vasospasm and markers for hematopathology, coagulopathy, and immunopathology. Patients were followed up at 4-month intervals with perimetry, optic disc imaging, and a standardized interventional protocol for intraocular pressure control. Univariate and proportional hazards models were used to identify factors that predicted progression. Main Outcome Measure: Visual field progression with standard automated perimetry. Results: Median follow-up was 5.3 years, with 167 patients (64.7%) completing 5 years or more and 67 patients (26.0%) completing 7 years or more. Abnormal baseline anticardiolipin antibody levels (hazard ratio [HR], 3.86; 95% confidence interval [CI], 1.60-9.31), higher baseline age (HR per year, 1.04; 95% CI, 1.01-1.07), female sex (HR, 1.94; 95% CI, 1.09-3.46), and higher mean follow-up intraocular pressure (HR per 1 mm Hg, 1.19; 95% CI, 1.05-1.36) before progression were associated with progression. Conclusions: The Canadian Glaucoma Study identified 4 independent predictive factors for glaucomatous field progression. Application to Clinical Practice: While confirming the importance of intraocular pressure in glaucoma progression, this study determined other risk factors that merit awareness. Trial Registration: clinicaltrials.gov Identifier: NCT00262626.