title: Incidence and prevalence of episcleritis and scleritis in Northern California.
abstract: OBJECTIVE
  To evaluate the incidence and prevalence of episcleritis and scleritis in a large well-defined population in Northern California.
  
  
  METHODS
  Secondary analysis was performed on data from the Northern California Epidemiology of Uveitis Study. The patient database of a large regional health maintenance organization was searched for all patients who potentially experienced ocular inflammatory disease during the 12-month study period. Medical records were reviewed for all potential patients to confirm ocular inflammatory disease and specific diagnosis, establish the time of onset, and collect additional data. Age- and sex-stratified quarterly study population data were used to calculate incidence rates and prevalence ratios.
  
  
  RESULTS
  After reviewing 2011 possible cases, 297 new-onset cases of episcleritis, 39 prior-onset cases of episcleritis, 25 new-onset cases of scleritis, and 8 prior-onset cases of scleritis were confirmed. For episcleritis, the overall incidence was 41.0 per 100,000 person-years and an annual prevalence ratio of 52.6 per 100,000. The overall incidence of scleritis was 3.4 per 100,000 person-years and an annual prevalence ratio of 5.2 per 100,000 persons. For both episcleritis and scleritis, there was a statistically significant increase in eye disease in older patients (P = 0.05 and <0.001, respectively) and for women in comparison with men (P = 0.001 and <0.001, respectively). Patients with scleritis were older than those with episcleritis (P = 0.017).
  
  
  CONCLUSIONS
  This study found that patients with scleritis were older than those with episcleritis and that women had higher rates of both episcleritis and scleritis compared with what men had.
authors.affiliation: *Department of Ophthalmology and Visual Science, Montefiore Medical Center and Albert Einstein College of Medicine, Bronx, NY; †Francis I. Proctor Foundation for Research in Ophthalmology and the Department of Ophthalmology, University of California, San Francisco, CA; ‡Department of Ophthalmology, Stanford University, Stanford, CA; §Department of Epidemiology and Population Health, Montefiore Medical Center and Albert Einstein College of Medicine, Bronx, NY; and ¶The Permanente Medical Group, Kaiser Permanente Medical Center, Oakland and Richmond, CA.
authors.forename: Grace
authors.initials: G
authors.lastname: Honik
authors.forename: Ira G
authors.initials: IG
authors.lastname: Wong
authors.forename: David C
authors.initials: DC
authors.lastname: Gritz
mesh_terms: D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D002140:California / Q000453:epidemiology; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D015994:Incidence; D007223:Infant; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D012189:Retrospective Studies; D015423:Scleritis / Q000453:epidemiology*; D017678:Sex Distribution; D055815:Young Adult