Outcomes of Trabeculectomy With Mitomycin C in Patients of Hispanic vs European Descent

Abstract

Importance: Previous studies suggest that race or ethnicity may influence glaucoma surgical outcomes.

Objective: To compare outcomes of initial trabeculectomy with mitomycin C (MMC) in patients of Hispanic descent with those in patients of European descent and identify prognostic factors for failure.

Design, setting, and participants: This retrospective matched-cohort study was conducted at a single-tertiary academic center. The study included 111 eyes from 96 patients of Hispanic descent that were matched to 111 eyes from 108 patients of European descent, based on age (±5 years), surgeon, lens status, and surgery date (±1 year). Ethnicity was self-determined by patients.

Exposure: Initial trabeculectomy with MMC.

Main outcome measures: Criteria A, B, and C defined qualified success as final intraocular pressure (IOP) of 18 mm Hg or less, 15 mm Hg or less, and 12 mm Hg or less, respectively, with corresponding IOP reduction of 20% or more, 25% or more, and 30% or more, or a decrease of 2 or more medications. Complete success required meeting the above criteria without medication use. Kaplan-Meier survival curves compared patients of Hispanic descent and patients of European descent success rates with log-rank tests. Cox proportional hazard models estimated the influence of ethnicity on surgical success adjusting for confounders.

Results: The Hispanic descent cohort included 59 females (61.5%) and 37 males (38.5%) with a mean (SD) age of 69.1 (9.9) years. The European descent cohort included 53 females (49.1%) and 55 males (50.9%) with a mean (SD) age of 69.2 (9.4) years. Qualified success rates at 5 years in Hispanic descent and European descent patients were 52% and 68% based on criteria A (difference, 16.7%; 95% CI, 4.0%-29.4%; P < .001), 45% and 61% according to criteria B (difference, 16.2%; 95% CI, 3.2%-29.1%; P = .01), and 31% and 51% based on criteria C (difference, 20.0%; 95% CI, 7.3%-32.6%; P = .002). On multivariable analyses, Hispanic descent was associated with higher failure rates with all complete and qualified success criteria (hazard ratio range, 2.07-3.03; P < .001). Early bleb leaks were more frequent in patients of Hispanic descent (14 eyes vs 6 eyes; P = .10).

Conclusion and relevance: In this study, Hispanic descent was associated with higher failure rate after initial trabeculectomy with adjunctive MMC compared with European descent. These findings need to be considered when glaucoma surgery is contemplated in patients of Hispanic descent, especially if these findings are confirmed in future studies that address some of the limitations of this single-center retrospective investigation.