title: Functional presbyopia in a rural Kenyan population: the unmet presbyopic need.
abstract: BACKGROUND
  Presbyopia is the most common reason for requiring spectacles in low-income regions, although the unmet need for presbyopic spectacles in these regions is very high. The aim of this study was to estimate the prevalence of presbyopia, and the functional impairment and spectacle use among persons with presbyopia in a rural Kenyan population.
  
  
  METHODS
  A cross-sectional study was carried out in the Rift Valley, Kenya. Clusters were selected through probability-proportionate to size sampling, and people aged >/=50 years within the clusters were identified through compact segment sampling. Within the context of this survey, 130 eligible participants were selected for interview and underwent near-vision testing. Functional presbyopia was defined as requiring at least +1.00 dioptre in order to read the N8 optotype at a distance of 40 cm in the participant's usual visual state. Participants were corrected to the nearest 0.25 dioptre in order to see N8. Unmet and met presbyopic need, and presbyopic correction coverage were calculated.
  
  
  RESULTS
  Functional presbyopia was found in 111 participants (85.4%). Mean age was lower in those with presbyopia (64.1 years vs. 71.5 years, P = 0.004). Increasing degree of addition required to see N8 was significantly associated with increased difficulty with reading (P = 0.04), sewing (P = 0.03), recognizing small objects (P = 0.02) and harvesting grains (P = 0.05). Among participants with functional presbyopia, 5.4% wore reading glasses and 25.2% had prior contact with an eye care professional. The unmet presbyopic need was 80.0%, met presbyopic need was 5.4% and presbyopic correction coverage was 6.3%. Cost was cited as the main barrier to spectacle use in 62% of participants with presbyopia.
  
  
  CONCLUSIONS
  In low-income regions, there is a high prevalence of uncorrected presbyopia, which is associated with near-vision functional impairment. Provision of spectacles for near vision remains a priority in low-income regions.
authors.affiliation: Centre for Eye Research Australia, University of Melbourne, Melbourne, Australia.
authors.forename: Justin C
authors.initials: JC
authors.lastname: Sherwin
authors.forename: Jill E
authors.initials: JE
authors.lastname: Keeffe
authors.forename: Hannah
authors.initials: H
authors.lastname: Kuper
authors.forename: F M Amirul
authors.initials: FM
authors.lastname: Islam
authors.forename: Andreas
authors.initials: A
authors.lastname: Muller
authors.forename: Wanjiku
authors.initials: W
authors.lastname: Mathenge
mesh_terms: D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D003430:Cross-Sectional Studies; D005139:Eyeglasses / Q000191:economics / Q000706:statistics & numerical data; D005260:Female; D017048:Health Care Costs; D006301:Health Services Needs and Demand / Q000706:statistics & numerical data; D006801:Humans; D007630:Kenya / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D011305:Presbyopia / Q000453:epidemiology* / Q000503:physiopathology* / Q000534:rehabilitation; D015995:Prevalence; D012424:Rural Population / Q000706:statistics & numerical data*; D012720:Severity of Illness Index; D017678:Sex Distribution