Estimated incidence of open-angle glaucoma in Olmsted County, Minnesota.

PURPOSE: To determine the incidence rates of open-angle glaucoma (OAG) in Olmsted County, MINNESOTA: DESIGN: Retrospective population-based estimate of incidence. PARTICIPANTS: From the medical histories of 60,666 residents of Olmsted County, Minnesota, who had ocular diagnoses during the study period, 114 subjects with newly diagnosed OAG were identified. METHODS: The database of the Rochester Epidemiology Project was used to identify all Olmsted County residents with a coded diagnosis of OAG, glaucoma suspect, or ocular hypertension during the period 1965 to 1980. Subjects newly diagnosed with and treated for OAG who also had documented clinical evidence of elevated intraocular pressure, optic nerve damage, and/or visual field loss consistent with glaucoma were included as incident cases. Population data for Olmsted County were drawn from United States Census data. Crude incidence data were adjusted to the age and gender distribution of the 1990 United States white population. MAIN OUTCOME MEASURES: Estimated incidence rates of OAG. RESULTS: The overall age- and gender-adjusted annual incidence rate of OAG in a predominantly Caucasian population is conservatively estimated to be 14.5 per 100,000 population. The rates increased with age from 1.6 in the fourth decade of life to 94.3 in the eighth decade. There was no significant difference in incidence by gender. The average annual rate of OAG in the last 2 years of the study was 27.7 compared with 12.3 before 1979. This difference is suggestive of the effect of the introduction of a new medical therapy (timolol) for OAG during the last 2 years. CONCLUSIONS: The incidence rates of OAG increase markedly with advancing age, and screening efforts should be targeted at both men and women in the older age groups. The advent of new diagnostic and therapeutic modalities can have an effect on incidence rates.

Effects of AGN 192024, a new ocular hypotensive agent, on aqueous dynamics.

PURPOSE: To determine the mechanism of intraocular pressure lowering for the Ocular Hypotensive Lipid, AGN 192024 (Allergan, Inc, Irvine, California). METHODS: Twenty-five normal human volunteers between the ages of 21 and 48 took part in a randomized, double-masked, placebo-controlled, paired-comparison study in which intraocular pressure, aqueous humor flow, and tonographic resistance to outflow were studied. Measurements of aqueous flow were made during the day and at night while subjects slept. Intraocular pressure was measured with the Goldmann tonometer, and resistance to outflow was measured by electronic recording Schiötz tonography. RESULTS: Intraocular pressure was decreased by 20% on day 3 in AGN 192024-treated eyes in comparison with placebo-treated eyes in normal subjects (P <.001). Aqueous humor flow was stimulated 13% during the day (P =.007) and 14% at night (P =.014) by the drug. Tonographic resistance to outflow was decreased 26% by AGN 192024 (P <.001), and apparent resistance to outflow (the ratio of intraocular pressure to aqueous flow) was decreased 31% (P <.001). Assuming that AGN 192024 does not cause prolonged lowering of episcleral venous pressure, the results show that pressure-insensitive outflow is enhanced by 50%, whereas tonographic facility of outflow (reciprocal of resistance) was enhanced 35%. CONCLUSIONS: AGN 192024 is an ocular hypotensive agent that works by enhancing both pressure-sensitive and pressure-insensitive aqueous humor outflow without diminishing aqueous humor formation.

Comparison of the efficacy of betaxolol-brinzolamide and timolol-dorzolamide as suppressors of aqueous humor flow in human subjects.

OBJECTIVE: To compare the efficacy of combinations of betaxolol-brinzolamide and timolol-dorzolamide as suppressors of aqueous humor flow and ocular hypotensive agents. DESIGN: Placebo-controlled, masked comparison of the two drug combinations. PARTICIPANTS: Twenty-five normal human volunteers with the fellow eye serving as control. METHODS OR TESTING: Fluorophotometric measurement of aqueous humor flow and pneumatonometric measurement of intraocular pressure. MAIN OUTCOME MEASURES: Aqueous humor flow and intraocular pressure. RESULTS: The betaxolol-brinzolamide combination lowered aqueous flow 39% to 44%, and the timololdorzolamide combination lowered aqueous flow 51%. The betaxolol-brinzolamide combination lowered intraocular pressure 14% to 19%, and the timolol-dorzolamide combination lowered it 18% to 24%. CONCLUSIONS: Both drug combinations were effective; the timolol-dorzolamide combination appeared to be the more effective of the two after short-term exposure (24 hours).