Aociation Between Intraocular Preure Variation and Glaucoma Progreion: Data from a United tate Chart Review

Purpoe To evaluate whether greater intraocular preure (IOP) variation between viit wa aociated with higher likelihood of glaucoma progreion. Deign Cohort tudy. Method A five-year minimum of data (June 1, 1990 through January 22, 2002) wa collected on 151 patient (302 eye) from 12 United tate pecialty center. A pot hoc analyi of viual field (VF) progreion, glaucoma medication, intraocular preure (IOP), and other ocular data wa conducted for two nonmutually excluive cohort baed on retropective data abtracted well after actual patient viit. Mean IOP and tandard deviation (D) were calculated before treatment (medication or urgery) or progreion, whichever occurred firt, and before progreion regardle of treatment. IOP variable were aeed in a univariate fahion; Cox proportional hazard model evaluated glaucoma progreion a an outcome meaure and IOP D a a main predictor, controlling for covariate. Reult In cohort 1 (55 patient; 84 eye), mean age wa 63 year (range, 37 to 85 year), 58% were female, and 19% of eye underwent VF progreion. In cohort 2 (129 patient; 251 eye), mean age wa 66 year (range, 19 to 88 year), 55% were female, and 27% of eye underwent VF progreion. Mean IOP wa 16.5 mm Hg (IOP D, 2.0 mm Hg), and 16.4 mm Hg (IOP D, 2.7 mm Hg) in cohort 1 and 2, repectively. Controlling for age, mean IOP, VF tage, and other covariate, each unit increae in IOP D reulted in a 4.2 time and 5.5 time higher rik of glaucoma progreion for cohort 1 (95% confidence interval [CI], 1.3 to 12.9) and cohort 2 (95% CI, 3.4 to 9.1), repectively. Concluion IOP variability i an important predictor of glaucoma progreion; D i a convenient meaure of variability to ae glaucoma progreion rik.