title: Keratoconus in the Medicare population.
abstract: OBJECTIVE
  To investigate the population-based prevalence of keratoconus in US individuals aged 65 years and older.
  
  
  METHODS
  Multiyear retrospective cross-sectional claims analysis.
  
  
  METHODS
  Fee-for-service claims from a 5% national sample of Medicare beneficiaries aged 65 years and older were reviewed. Claims records were queried on an annual basis for the years 1999 through 2003 for ICD-9 codes specific to keratoconus. The number of beneficiaries with keratoconus-related claims was counted for each calendar year.
  
  
  RESULTS
  The number of beneficiaries receiving care for keratoconus rose steadily from 15.7/100,000 beneficiaries in 1999 to 18.5/100,000 in 2003, averaging 17.5/100,000 across the 5 years of the study. Keratoconus rates declined with increasing age but did not differ by gender. Keratoconus care was more prevalent in whites than in other races.
  
  
  CONCLUSIONS
  Keratoconus is an uncommon disease in the Medicare population. Longitudinal analysis of Medicare claims data may provide a useful tool for monitoring uncommon diseases, such as keratoconus, in the elderly.
authors.affiliation: Minnesota Eye Consultants, Minneapolis, MN 55404, USA. swreeves@mneye.com
authors.forename: Sherman W
authors.initials: SW
authors.lastname: Reeves
authors.forename: Leon B
authors.initials: LB
authors.lastname: Ellwein
authors.forename: Terry
authors.initials: T
authors.lastname: Kim
authors.forename: Roberta
authors.initials: R
authors.lastname: Constantine
authors.forename: Paul P
authors.initials: PP
authors.lastname: Lee
mesh_terms: D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D044383:Black People / Q000706:statistics & numerical data; D003430:Cross-Sectional Studies; D006801:Humans; D007640:Keratoconus / Q000453:epidemiology* / Q000208:ethnology; D006278:Medicare / Q000706:statistics & numerical data*; D014481:United States / Q000453:epidemiology; D044465:White People / Q000706:statistics & numerical data; D001741:Black or African American