title: Optic neuritis among National Health Insurance enrollees in Taiwan, 2000-2004.
abstract: BACKGROUND
  The objective was to examine the incidence of optic neuritis in Taiwan. A 5-year longitudinal, nationwide, population-based study was conducted. The participants were a random sample of 191,761 subjects, or about 1% of the enrollees in the National Health Insurance program of Taiwan.
  
  
  METHODS
  We identified subjects who had at least 1 service claim for ambulatory or inpatient care with a principal diagnosis of optic neuritis between 2000 and 2004. We calculated and statistically analyzed the rates of optic neuritis. The main outcome measures were the incidence rates of optic neuritis.
  
  
  RESULTS
  From 2000 to 2004, the total cumulative incidence was 1.33 per 1,000 (1.00 vs. 1.67 for male vs. female subjects; p < 0.001, chi(2) test). The cumulative incidence rates for the age groups of 0-19, 20-39, 40-59 and >or=60 years were 0.33, 1.05, 2.16 and 2.81 cases per 1,000, respectively. Among the subjects aged 40-59 years, the cumulative incidence was higher in women than in men (p < 0.001, chi(2) test). The incidence density of developing multiple sclerosis after optic neuritis was 0.41% per person-year, and the cumulative incidence of multiple sclerosis after a new diagnosis of optic neuritis was 0.78%.
  
  
  CONCLUSIONS
  We believe our study is the first nationwide investigation of the incidence rates of optic neuritis in Taiwan. In our investigation, the cumulative incidence peaked among the subjects aged 40-59 years, especially in women. In Taiwan, patients with optic neuritis have a notably low rate of conversion to multiple sclerosis.
authors.affiliation: Department of Ophthalmology, Taipei City Hospital, Taipei, Taiwan, ROC.
authors.forename: Lin-Chung
authors.initials: LC
authors.lastname: Woung
authors.forename: Ching-Heng
authors.initials: CH
authors.lastname: Lin
authors.forename: Ching-Yao
authors.initials: CY
authors.lastname: Tsai
authors.forename: Ming-Tsu
authors.initials: MT
authors.lastname: Tsai
authors.forename: Jieh-Ren
authors.initials: JR
authors.lastname: Jou
authors.forename: Pesus
authors.initials: P
authors.lastname: Chou
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D015994:Incidence; D007223:Infant; D008297:Male; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000175:diagnosis / Q000453:epidemiology; D009313:National Health Programs / Q000706:statistics & numerical data*; D009902:Optic Neuritis / Q000175:diagnosis / Q000453:epidemiology*; D011159:Population Surveillance; D012737:Sex Factors; D013624:Taiwan