PURPOSE: To investigate baseline prognostic factors predicting rapid deterioration of the visual field in primary open-angle glaucoma patients. METHODS: Seven hundred sixty-seven eyes of 566 glaucoma patients from the Advanced Glaucoma Intervention Study (AGIS) and the clinical database from Jules Stein Eye Institute's Glaucoma Division were included. The rates of decay at each visual field test location were calculated with pointwise exponential regression analysis (PER), and the rates were separated into faster and slower components for each series. Subjects with a faster component decay rate (≥ 36%/y) were defined as rapid progressors. Sex, race, age, visual acuity, intraocular pressure, mean deviation (MD), number of medications, use of diabetic or hypertension medications, and vertical cup-to-disc ratio at baseline were entered in a multivariable prognostic logistic regression model. RESULTS: The average (± SD) MD was -8.02 (± 6.13), and the average age was 68.64 (± 11.71) years for the study group. Two hundred twenty-two eyes (28.9%) were identified as rapid progressors. The following baseline factors were predictors of faster deterioration: worse MD (P < 0.001, odds ratio [OR]: 1.11; 95% confidence interval [CI]: 1.07-1.15), larger vertical cup-to-disc ratio (P = 0.001, OR: 1.23; 95% CI: 1.09-1.39), and older age (P = 0.02, OR: 1.24; 95% CI: 1.04-1.48). After excluding the variables related to glaucoma severity at baseline (baseline MD and baseline vertical cup-to-disc ratio), the likelihood of being a rapid progressor was 54% greater in African Americans than in Caucasians (P = 0.03, OR: 1.55; 95% CI: 1.06-2.27). CONCLUSIONS: Patients with more severe glaucomatous damage, as measured by both visual field or optic disc cupping and older age, are at highest risk for rapid worsening of the disease, as are African Americans compared to Caucasians. More aggressive treatment of such patients should be considered to prevent visual disability.