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Published on: September 20, 2024
Presbyopia and Ocular Conditions Causing Near Vision Impairment in Older Adults From the Brazilian Amazon Region
Cristina Coimbra Cunha1, Adriana Berezovsky1, João Marcello Furtado1
1Universidade Federal de São Paulo (UNIFESP), Escola Paulista de Medicina, Departamento de Oftalmologia e Ciências Visuais, São Paulo, Brazil.
Purpose:
To investigate the prevalence and causes of near vision impairment (NVI) in a population of older adults from the Brazilian Amazon Region.
Design:
Population-based cross-sectional study.
Methods:
Cluster sampling was used in randomly selecting subjects 45 years of age and older from urban and rural areas of Parintins city, Brazil. Participants underwent ophthalmic examination, including uncorrected (UCNVA), presenting (PNVA), and best-corrected near visual acuity (BCNVA) from each eye; biomicroscopy; funduscopy; and subjective refraction, including testing with additional lenses for near vision optical correction. A principal cause for NVI was assigned by the ophthalmologist and presbyopia was defined as UCNVA ≤ 20/40 changing to > 20/40 with BCNVA. Free-of-charge glasses were provided for those in need.
Results:
A total of 2384 subjects were enumerated and 2025 had reliable NVA measurements from both eyes. The prevalence of NVI in the better-seeing eye was 96.5% with UCNVA, decreasing to 81.1% with PNVA and to 20.5% with BCNVA. Presbyopia was the principal cause of NVI in 71.8%, followed by cataract (16.5%) and pterygium (2.5%), and was associated with younger age and high schooling. Glasses for near vision were prescribed and provided to 1414 (69.8%) participants.
Conclusions:
A high prevalence of NVI was detected even in those wearing glasses for near. Prescription and provision of low-cost reading glasses should be considered by Brazilian health authorities to address this easily and promptly correctable form of vision impairment.
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