97th DOG Annual Meeting 1999
CHANGING FACES OF OPEN-ANGLE GLAUCOMA: DEFINITIONS AND PREVALENCES. THE ROTTERDAM STUDY
Purpose: To examine determinants and prevalence of open-angle glaucoma (OAG) in a general Caucasian population.
Methods: Population-based, cross-sectional study. A total of 6781 subjects aged 55 years or over participated in this study (6293 independently living subjects and 488 living in nursing homes). The diagnosis of OAG was based on semi-automated measurements of the optic disc (vertical cup-to-disc ratio (VCDR), minimal width of neural rim, or asym-metry in VCDR between both eyes) and visual field testing with kinetic Goldmann perimetry. Intraocular pressure (IOP) was measured with Goldmann applanation tonometry. All separate criteria for the diagnosis of OAG were assessed independently of each other.
Results: Mean VCDR was 0.54. In 7.5% of the subjects a VCDR ³ 0.7 was found. The prev-al-ence of visual field defects compatible with OAG and without other causes was 1.5%. Overall prevalence of OAG in the independently living subjects was 1.1% (95% CI 0.8, 1.4; 69 cases). Prevalence of OAG was almost three times higher in men than in women (Odds ratio 2.7, 95%CI 1.5, 4.9). The risk of OAG increased with 7% per year of age (95% CI 3.0%, 10.0%). Different criteria for diagnosis of OAG resulted in prevalence figures ranging from 0.1% to 1.2%. Criteria used by other population-based studies resulted in 12 fold prevalence differences.
Conclusion: The overall prevalence of OAG in the present study was 1.1%. The prevalence was higher in men than in women and increased with age. Prevalence figures differed by a factor 12 when using different criteria to define OAG. Diagnostic standardization is necessary for comparison of epidemiologic glaucoma studies.
The Netherlands Ophthalmic Research Institute and Dept of Ophthalmology, Academic Medical Center, Amsterdam; Department of Epidemiology & Biostatistics and Department of Ophthalmology, Erasmus University Rotterdam, The Netherlands.