title: Neuroretinal Rim Area Change in Glaucoma Patients With Visual Field Progression Endpoints and Intraocular Pressure Reduction. The Canadian Glaucoma Study: 4.
abstract: OBJECTIVE
  To compare rim area rates in patients with and without the visual field (VF) progression endpoint in the Canadian Glaucoma Study and determine whether intraocular pressure (IOP) reduction following the endpoint altered rim area rate.
  
  
  METHODS
  Prospective multicenter cohort study.
  
  
  METHODS
  setting: University hospitals.
  
  
  METHODS
  Two hundred and six patients with open-angle glaucoma were examined at 4-month intervals with standard automated perimetry and confocal scanning laser tomography.
  
  
  METHODS
  After the endpoint, IOP was reduced by ≥20%.
  
  
  METHODS
  Univariate analysis for change in rim area rate and multivariable analysis to adjust for independent covariates (eg, age, sex, and IOP).
  
  
  RESULTS
  Patients with an endpoint (n = 59) had a worse rim area rate prior to the endpoint compared to those without (n = 147; median [interquartile range]: -14 [-32, 11] × 10(-3) mm(2)/y and -5 [-14, 5] × 10(-3) mm(2)/y, respectively, P = .02). In univariate analysis, there was no difference in rim area rate before and after the endpoint (median difference [95% CI], 8 (-10, 24) × 10(-3) mm(2)/y), but the muItivariate analysis showed that IOP reduction >2 mm Hg after the endpoint was strongly linked to a reduction in rim area rate decline (8 × 10(-3) mm(2)/y for each additional 1 mm Hg reduction).
  
  
  CONCLUSIONS
  Patients with a VF endpoint had a median rim area rate that was nearly 3 times worse than those without an endpoint. Lower mean follow-up IOP was independently associated with a slower decline in rim area.
authors.affiliation: Departments of Ophthalmology and Visual Sciences, Dalhousie University, Halifax, Canada.
authors.forename: Rizwan
authors.initials: R
authors.lastname: Malik
authors.affiliation: Departments of Ophthalmology and Visual Sciences, Dalhousie University, Halifax, Canada.
authors.forename: Neil
authors.initials: N
authors.lastname: O'Leary
authors.affiliation: Departments of Ophthalmology and Visual Sciences, University of British Columbia, Vancouver, Canada.
authors.forename: Frederick S
authors.initials: FS
authors.lastname: Mikelberg
authors.affiliation: Department of Ophthalmology, McGill University, Montreal, Canada.
authors.forename: A Gordon
authors.initials: AG
authors.lastname: Balazsi
authors.affiliation: Departments of Ophthalmology and Visual Sciences, Dalhousie University, Halifax, Canada.
authors.forename: Raymond P
authors.initials: RP
authors.lastname: LeBlanc
authors.affiliation: Department of Ophthalmology, Université de Montréal, Montreal, Canada.
authors.forename: Mark R
authors.initials: MR
authors.lastname: Lesk
authors.affiliation: Departments of Ophthalmology and Visual Sciences, Dalhousie University, Halifax, Canada.
authors.forename: Marcelo T
authors.initials: MT
authors.lastname: Nicolela
authors.affiliation: Departments of Ophthalmology and Visual Sciences, University of Toronto, Toronto, Canada.
authors.forename: Graham E
authors.initials: GE
authors.lastname: Trope
authors.affiliation: Departments of Ophthalmology and Visual Sciences, Dalhousie University, Halifax, Canada. Electronic address: bal@dal.ca.
authors.forename: Balwantray C
authors.initials: BC
authors.lastname: Chauhan
mesh_terms: D000368:Aged; D002170:Canada; D015331:Cohort Studies; D018450:Disease Progression; D023381:Endpoint Determination; D005260:Female; D005902:Glaucoma, Open-Angle / Q000175:diagnosis*; D006801:Humans; D007429:Intraocular Pressure / Q000502:physiology*; D008297:Male; D018613:Microscopy, Confocal; D008875:Middle Aged; D009412:Nerve Fibers / Q000473:pathology*; D009898:Optic Disk / Q000473:pathology; D009901:Optic Nerve Diseases / Q000175:diagnosis*; D011446:Prospective Studies; D012165:Retinal Ganglion Cells / Q000473:pathology*; D014054:Tomography; D014786:Vision Disorders / Q000175:diagnosis*; D058609:Visual Field Tests; D014794:Visual Fields