Presentation of glaucoma in an urban tertiary care hospital in South America: legal blindness and prevalence

Purpose: To determine disease severity in glaucoma patients who presented to a tertiary care service for the first time and to determine the prevalence of different types of glaucoma. Methods: Retrospective analysis of data of patients referred to the Glaucoma Service at the Santa Casa de Misericórdia de São Paulo, Brazil in 2007. A complete chart review from 448 patients was done; data regarding age, gender, ethnicity, family history, duration of the disease, previous treatment, best corrected visual acuity, cup-to-disc ratio, intraocular pressure, diagnosis and treatment were collected. Glaucoma was diagnosed by the presence of typical optic disk abnormalities, disregarding IOP values. Results: 52.3% of patients presented visual acuity less than or equal to 20/200 and 67.7% presented cup-to-disc ratio between 0.8 and 1.0 in the worse-seeing eye; 13.4% of patients were considered legally blind. Primary open angle glaucoma was the most prevalent form of glaucoma (54.2%, 95% CI: 48.5–59.5) and chronic angle closure glaucoma was the second most frequent (11.5%, 95% CI: 8.25–15.5). Conclusion: A considerable rate of patients (almost 60% in the better-seeing eye and 70% in the worse-seeing eye) presented with advanced glaucoma. Strategies that create conditions for early diagnosis are deemed necessary to reduce glaucoma-related blindness in the Brazilian population.