Topiramate use and the risk of glaucoma development: A population-based follow-up study

Purpose: To investigate the risk of glaucoma development after being prescribed topiramate. Design: A retrospective, population-based cohort study using an administrative database. Methods: The study group comprised 1956 patients who received their first prescription of topiramate between 2001 and 2007. The comparison cohort consisted of 15 648 randomly matched patients who never took topiramate. Each sampled patient was traced for a 1-year period from his or her index date to identify patients who subsequently received a diagnosis of glaucoma. Results: Glaucoma was diagnosed in 0.36%, 0.05%, and 0.66% of the study cohort during the first month, second to third month, and fourth to twelfth month following the index date, respectively. For the comparison cohort, glaucoma was diagnosed in 0.04%, 0.11%, and 0.46% of subjects during the first month, second to third month, and fourth to twelfth month following the index date, respectively. After adjusting for potential confounding factors, patients prescribed topiramate were found to have a 7.41-fold (95% confidence interval [CI] = 2.45-22.46) greater risk of subsequently being diagnosed with glaucoma than the comparison cohort during the first month after the index date. However, this association became statistically nonsignificant during the second-to-third-month and fourth-to-twelfth-month periods following the index date between the 2 cohorts (adjusted hazard ratio, 0.56, 95% CI = 0.07-4.29; and 1.35, 95% CI = 0.74-2.47, respectively). Conclusions: Topiramate use in Taiwan was associated with a significantly increased risk of being diagnosed with glaucoma within the first month after receiving a prescription for the drug.