Vascular risk factors for primary open angle glaucoma: the Egna-Neumarkt study

OBJECTIVE: To assess the impact of vascular risk factors on the prevalence of primary open angle glaucoma. DESIGN: Population-based cross-sectional study. PARTICIPANTS: Four thousand two hundred ninety-seven patients more than 40 years of age underwent a complete ocular examination in the context of the Egna-Neumarkt Glaucoma Study. INTERVENTION: Ocular examinations were performed by trained, quality-controlled ophthalmologists according to a predefined standardized protocol including medical interview, blood pressure reading, applanation tonometry, computerized perimetry, and optic nerve head examination. MAIN OUTCOME MEASURES: Prevalences of ocular hypertension, primary open-angle glaucoma, normal-tension glaucoma, and other types of glaucoma were determined. Correlation coefficients were calculated for the association between systemic blood pressure and age-adjusted intraocular pressure (IOP) and between age and both intraocular and systemic blood pressures. Odds ratios were computed to assess the risk of primary open-angle glaucoma and normal-tension glaucoma in relation to systemic hypertension or antihypertensive medication, blood pressure levels, diastolic perfusion pressure, and a number of other cardiovascular risk factors. RESULTS: A positive correlation was found between systemic blood pressure and IOP, and an association was found between diagnosis of primary open-angle glaucoma and systemic hypertension. Lower diastolic perfusion pressure is associated with a marked, progressive increase in the frequency of hypertensive glaucoma. No relationship was found between systemic diseases of vascular origin and glaucoma. CONCLUSIONS: Our data are in line with those reported in other recent epidemiologic studies and show that reduced diastolic perfusion pressure is an important risk factor for primary open-angle glaucoma.