Pterygium in adults from the Brazilian Amazon Region: prevalence, visual status and refractive errors

• Published in: British journal of ophthalmology Vol. 104; no. 6; pp. 757 - 763
• Main Authors: Fernandes, Arthur G, Salomão, Solange R, Ferraz, Nívea N, Mitsuhiro, Márcia H, Furtado, Joao M, Muñoz, Sergio, Cypel, Marcela C, Cunha, Cristina C, Vasconcelos, Galton C, Sacai, Paula Y, Morales, Paulo H, Cohen, Marcos J, Cohen, Jacob M, Watanabe, Sung S, Campos, Mauro, Belfort Junior, Rubens, Berezovsky, Adriana
• Format: Journal Article
• Language: English
• Published: England BMJ Publishing Group LTD 01.06.2020
• Subjects: Age; Age Distribution; Aged; Brazil - epidemiology; Cross-Sectional Studies; Female; Humans; Informed consent; Male; Middle Aged; Population; Population Surveillance; Prevalence; Pterygium - complications; Pterygium - epidemiology; Refractive Errors - epidemiology; Refractive Errors - etiology; Refractive Errors - physiopathology; Rural areas; Rural Population; Sociodemographics; Visual Acuity; Visual impairment; Brazil; Pterygium; Prevalence; Refractive Errors; Blindness; Visual Impairment
• ISSN: 0007-1161; 1468-2079
• DOI: 10.1136/bjophthalmol-2019-314131

AimsTo determine prevalence of pterygium, its role as main cause of unilateral and bilateral visual impairment and blindness and its impact on refractive errors from adults living in a high ultraviolet exposure area in the Brazilian Amazon Region.MethodsCluster sampling was used in randomly selecting subjects ≥45 years of age from urban and rural areas of Parintins city. Eligible subjects were enumerated through a door-to-door household survey and invited for an eye exam including refraction. Pterygium was assessed considering location (nasal, temporal or both) and size (<3 mm or ≥3 mm reaching or not pupillary margin).ResultsA total of 2384 persons were enumerated and 2041 (85.6%) were examined. Prevalence of pterygium was 58.8% (95% CI 53.8% to 63.7%) and associated with male gender (OR=1.63; 95% CI 1.37 to 1.94; p=0.001), while higher education was a protective factor (OR=0.63; 95% CI 0.44 to 0.92; p=0.018). Older age and rural residence were associated with pterygium ≥3 mm reaching or not pupillary margin, while higher education was a protective factor for pterygium ≥3 mm reaching pupillary margin. Prevalence of pterygium as cause of visual impairment and blindness was 14.3% and 3.9%, respectively. Significantly higher hyperopic refractive errors were found in eyes with pterygium ≥3 mm reaching or not pupillary margin.ConclusionsPterygium was highly prevalent and the second cause of visual impairment and blindness after provision of refractive correction. Risk factors for pterygium were male gender, advanced age, lower education and rural residency. Strategies to provide pterygium early detection and proper management should be considered by healthcare authorities in this population.