title: Poverty and Blindness in Nigeria: Results from the National Survey of Blindness and Visual Impairment.
abstract: OBJECTIVE
  Poverty can be a cause and consequence of blindness. Some causes only affect the poorest communities (e.g. trachoma), and poor individuals are less likely to access services. In low income countries, cataract blind adults have been shown to be less economically active, indicating that blindness can exacerbate poverty. This study aims to explore associations between poverty and blindness using national survey data from Nigeria.
  
  
  METHODS
  Participants ≥40 years were examined in 305 clusters (2005-2007). Sociodemographic information, including literacy and occupation, was obtained by interview. Presenting visual acuity (PVA) was assessed using a reduced tumbling E LogMAR chart. Full ocular examination was undertaken by experienced ophthalmologists on all with PVA <6/12 in either eye. Causes of vision loss were determined using World Health Organization guidelines. Households were categorized into three levels of poverty based on literacy and occupation at household level.
  
  
  RESULTS
  A total of 569/13,591 participants were blind (PVA <3/60, better eye; prevalence 4.2%, 95% confidence interval [CI] 3.8-4.6%). Prevalences of blindness were 8.5% (95% CI 7.7-9.5%), 2.5% (95% CI 2.0-3.1%), and 1.5% (95% CI 1.2-2.0%) in poorest, medium and affluent households, respectively (p = 0.001). Cause-specific prevalences of blindness from cataract, glaucoma, uncorrected aphakia and corneal opacities were significantly higher in poorer households. Cataract surgical coverage was low (37.2%), being lowest in females in poor households (25.3%). Spectacle coverage was 3 times lower in poor than affluent households (2.4% vs. 7.5%).
  
  
  CONCLUSIONS
  In Nigeria, blindness is associated with poverty, in part reflecting lower access to services. Reducing avoidable causes will not be achieved unless access to services improves, particularly for the poor and women.
authors.affiliation: a Department of Ophthalmology , Aminu Kano Teaching Hospital , Kano , Nigeria .
authors.forename: A
authors.initials: A
authors.lastname: Tafida
authors.affiliation: b College of Health Sciences, University of Abuja , Nigeria .
authors.forename: F
authors.initials: F
authors.lastname: Kyari
authors.affiliation: c Ophthalmology Department , Abubakar Tafawa Balewa University Teaching Hospital , Bauchi , Nigeria .
authors.forename: M M
authors.initials: MM
authors.lastname: Abdull
authors.affiliation: d International Centre for Eye Health, Department of Clinical Research, London School of Hygiene & Tropical Medicine , London , UK , and.
authors.forename: S
authors.initials: S
authors.lastname: Sivasubramaniam
authors.affiliation: d International Centre for Eye Health, Department of Clinical Research, London School of Hygiene & Tropical Medicine , London , UK , and.
authors.forename: G V S
authors.initials: GV
authors.lastname: Murthy
authors.affiliation: e Office of the Permanent Secretary, Federal Ministry of Health , Abuja , Nigeria.
authors.forename: I
authors.initials: I
authors.lastname: Kana
authors.affiliation: d International Centre for Eye Health, Department of Clinical Research, London School of Hygiene & Tropical Medicine , London , UK , and.
authors.forename: Clare E
authors.initials: CE
authors.lastname: Gilbert
mesh_terms: D000328:Adult; D017677:Age Distribution; D001766:Blindness / Q000453:epidemiology*; D003430:Cross-Sectional Studies; D005128:Eye Diseases / Q000453:epidemiology; D005260:Female; D006297:Health Services Accessibility; D006306:Health Surveys; D006801:Humans; D008297:Male; D008875:Middle Aged; D009549:Nigeria / Q000453:epidemiology; D009790:Occupations; D011203:Poverty / Q000706:statistics & numerical data*; D015995:Prevalence; D017678:Sex Distribution; D019987:Persons with Visual Disabilities / Q000706:statistics & numerical data*
keywords: Blindness; Nigeria; national survey; poverty