Effect of glaucoma on corneal graft survival according to indication for penetrating keratoplasty.

PURPOSE: To determine whether the risk of graft failure in patients with glaucoma is dependent on the indication for penetrating keratoplasty (PK).
DESIGN: Retrospective cohort study.
METHODS: All patients on the United Kingdom Transplant Registry undergoing their first PK over a 7-year period with at least 1 year of follow-up were included. Data were collected on indication for PK, presence and management of glaucoma, graft diameter, recipient risk factors, and graft survival. Kaplan-Meier survival curves, a Cox regression model, and χ(2) and t tests were used in group comparisons.
RESULTS: A total of 6255 transplants in eyes without glaucoma and 1994 in eyes with glaucoma were analyzed. Three-year transplant survival was 86% and 72% respectively (P < .0001), and 73% in eyes with medically managed glaucoma compared to 63% in surgically managed glaucoma (P = .07). Glaucoma patients undergoing PK for pseudophakic bullous keratopathy or Fuchs dystrophy had significantly increased relative risks of graft failure (1.5 and 1.9 with topical and 2.0 and 3.1 with oral antiglaucoma medication respectively, compared to those without glaucoma). There was no equivalent significant difference for those with keratoconus, previous noncataract ocular surgery, trauma, or noninfectious ulcerative keratitis. Endothelial decompensation accounted for a significantly greater proportion of graft failure in recipients with glaucoma (topical [9%] and oral medication [13%]) than in those without glaucoma (3%) (P < .001). DISCUSSION: The presence of glaucoma carries an increased risk of graft failure, in particular from endothelial decompensation. This risk is, however, also dependent on the indication for PK, with transplants undertaken for primary corneal endothelial disease carrying a higher risk.