Epidemiologic approach to open-angle glaucoma: 2. Survival analysis of adverse drug reactions. Report of the Canadian...

Medical treatment, intraocular pressure (IOP) and adverse drug reactions were recorded in a prospective multicentre study of 71 unselected, newly diagnosed cases of open-angle glaucoma. Eight ophthalmologists recorded standard information at five visits over a mean interval of 12.1 months. No limitations were imposed on the choice of drugs or interval between visits. The IOP was satisfactorily controlled throughout the follow-up period with the first drug prescribed in 36% of eyes. In an additional 10% to 13% the IOP was stabilized with alternative therapy, prescribed for approximately one-third of eyes per visit. A total of 27 patients reported 18 severe and 31 mild suspected adverse reactions during the follow-up period. Survival analysis showed that there was no significant difference between the proportions of patients continuing treatment with the first, second and third drug prescribed (half-life of treatment approximately 210 days in all three cases). However, when only changes for unsatisfactory pressure were considered, the half-life of treatment was significantly longer, 350 days (p = 0.02).