Predictive Value of the Water Drinking Test and the Risk of Glaucomatous Visual Field Progression.

Abstract

The purpose of this is to test the hypothesis the intraocular pressure (IOP) peaks during a stress test [the water drinking test (WDT)] can estimate the risk of future visual field progression in treated primary open-angle glaucoma (POAG) patients. Design: Prospective, longitudinal study. Clinical practice. Treated POAG patients whose IOP was ≤18 mm Hg and who had no IOP-lowering interventions between the date of the WDT and the last eligible visual field. At baseline examination, patients underwent the WDT and were then followed at regular intervals with office-based IOP measurements and visual field testing. Cox-proportional hazards survival analysis testing the predictive value of IOP peaks during the WDT versus IOP measurements during office hours on visual field progression. A total of 144 eyes of 96 patients with baseline visual field damage ranging from mild to severe followed for a mean of 28 months were analyzed. In the multivariable analysis adjusting for potential confounders, higher IOP peaks during the WDT were predictive of future visual field progression (hazard ratio=1.11; 95% confidence interval, 1.02 to 1.21; P=0.013). The average and peak IOP during office hours over the same follow-up period were not significantly associated with progression (P=0.651 and 0.569, respectively). IOP peaks detected with the WDT were predictive of future visual field progression in a treated POAG population. This stress test could be a useful tool for risk assessment in daily practice.