title: Prevalence and associations of cataract in indigenous Australians within central Australia: the Central Australian Ocular Health Study.
abstract: OBJECTIVE
  To determine the prevalence and associations of cataract within the indigenous Australian population living in central Australia.
  
  
  METHODS
  1884 individuals aged > or =20 years, living in one of 30 remote communities within the statistical local area of 'central Australia' were recruited for this study. This equated to 36% of those aged > or =20 years and 67% of those aged > or =40 years within this district. Slit-lamp examination was performed. The degree and subtype of cataract was graded using the Lens Opacities Classification System III criteria. A cataract was defined as a nuclear opalescence > or =4.0, a cortical opacity > or =3.0, a posterior subcapsular opacity > or =2.0, a visual acuity worse than 6/12 or a visual acuity worse than 6/60 due to cataract. The prevalence of cataract in one or both eyes was presented for each of the definitions.
  
  
  RESULTS
  Nuclear opalescence cataract was present in 13.5% (18.5% of those > or =40 years); cortical opacity cataract was present in 13.1% (17.7% of those > or =40 years); and posterior subcapsular cataract was present in 15.8% (21.0% of those > or =40 years). 12.6% of patients (17.3% of those > or =40 years) and 4.4% of patients (5.9% of those > or =40 years) had a cataract that resulted in a visual acuity of worse than 6/12 and worse than 6/60, respectively. All cataracts were associated with advancing age. Posterior subcapsular cataract was associated with self-reported diabetes.
  
  
  CONCLUSIONS
  There is a higher prevalence of cataract among indigenous Australians living within remote central Australia compared with the non-indigenous population. Services for this population need to be designed with this in mind when planning resource allocation.
authors.affiliation: Department of Ophthalmology, Flinders Medical Centre, Flinders Drive, Bedford Park, SA 5042, Australia. john.landers@bigpond.com
authors.forename: John
authors.initials: J
authors.lastname: Landers
authors.forename: Tim
authors.initials: T
authors.lastname: Henderson
authors.forename: Jamie
authors.initials: J
authors.lastname: Craig
mesh_terms: D000328:Adult; D017677:Age Distribution; D001251:Astigmatism / Q000453:epidemiology; D001315:Australia / Q000453:epidemiology; D002386:Cataract / Q000150:complications / Q000453:epidemiology* / Q000209:etiology; D005139:Eyeglasses; D005260:Female; D006801:Humans; D006956:Hyperopia / Q000453:epidemiology; D016013:Likelihood Functions; D008297:Male; D008875:Middle Aged; D009216:Myopia / Q000453:epidemiology; D015995:Prevalence; D012030:Refractive Errors / Q000150:complications / Q000453:epidemiology* / Q000503:physiopathology; D012307:Risk Factors; D012424:Rural Population / Q000706:statistics & numerical data*; D014792:Visual Acuity