title: Age at onset curves of retinitis pigmentosa.
abstract: OBJECTIVE
  To calculate age at onset curves of retinitis pigmentosa (RP) to resolve the difficulty in calculating the recurrence risk in a family. Retinitis pigmentosa is a common hereditary retinal disease that leads to blindness. It is a slow-onset disease, and family members of patients sometimes develop RP later.
  
  
  METHODS
  We studied 370 patients with typical RP. The age at onset was defined as when the patient's RP was diagnosed by an ophthalmologist. After confirmation that the age at onset came from normal distribution, we drew the age at onset curves.
  
  
  RESULTS
  The average age when patients were diagnosed with RP was 35.1 years, and the median age was 36.5. The onset ratio straightly increased with age until 65 years, so the onset ratio was relatively low at young ages.
  
  
  CONCLUSIONS
  The age at onset curves are quite simple and useful tools that facilitate counseling at an RP clinic. Without them, the recurrence risk would be misleading.
authors.affiliation: Department of Ophthalmology, Osaka University Medical School, O 2-2 Yamadaoka, Japan. moto@ophthal.med.osaka-u.ac.jp
authors.forename: Motokazu
authors.initials: M
authors.lastname: Tsujikawa
authors.forename: Yuko
authors.initials: Y
authors.lastname: Wada
authors.forename: Marie
authors.initials: M
authors.lastname: Sukegawa
authors.forename: Miki
authors.initials: M
authors.lastname: Sawa
authors.forename: Fumi
authors.initials: F
authors.lastname: Gomi
authors.forename: Kohji
authors.initials: K
authors.lastname: Nishida
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Tano
mesh_terms: D000293:Adolescent; D000328:Adult; D017668:Age of Onset; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D007564:Japan / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D010375:Pedigree; D012008:Recurrence; D012174:Retinitis Pigmentosa / Q000453:epidemiology* / Q000235:genetics; D018570:Risk Assessment