The overall aim of this study is to determine risk factors for the development of high intraocular pressure (IOP) and glaucoma visual field defects (GVFD). These factors include systemic hypertension, antihypertensive therapy, cardiovascular risk factors, family history, demographic and othe variables. Previous studies have provided suggestive but inconclusive evidence that systemic blood pressure levels are involved in glaucoma pathogenesis. Because blood pressure and IOP levels may be related, hypertensives could be at high risk of developing ocular hypertension (elevated IOP). In addition, hypertensives may be at increased risk of GVFD afte receiving antihypertensive drugs. The first objective of this study is to evaluate the relationships between hypertension, its treatment and open-angle glaucoma risk. This information is important for patient management and for an increased understanding of glaucoma pathogenesis as well. The study will: 1) determine whether hypertension and antihypertensive treatment are associated with an increased risk of GVFD, and 2) determine whether hypertension increases the risk of ocular hypertension. The second objective is to evaluate the independent contribution of cardiovascular risk factors, familial, socioeconomic, occupational and other environmental variables to the risk of GVFD and/or ocular hypertension. The study will determine which of these factors discriminate between ocular hypertensive and glaucoma patients. This information will be obtained by a case-control study which will consist of private ophthalmologic patients, 45-74 years, to be divided in three age-sex matched groups of 200 patients each: I. Glaucoma patients with GVFD and high IOP, II. Ocular hypertensive patients with high IOP, but no evidence of optic nerve damage and III. Control patients with normal IOP and no GVFD. All patients will be interviewed and will have blood pressure measurements, tonometry, visual field testing and fundus photography. Information on past medical history, antihypertensive therapy and other factors will be obtained by patient interview and confirmed by the treating physician. Groups will be compared regarding the frequency of the variables under investigation. Estimates of the magnitude of the risk involved will be obtained from these comparisons.