title: Prevalence and incidence of systemic lupus erythematosus in a population-based registry of American Indian and Alaska Native people, 2007-2009.
abstract: OBJECTIVE
  Few studies have investigated the epidemiology of systemic lupus erythematosus (SLE) in American Indian and Alaska Native populations. The objective of this study was to determine the prevalence and incidence of SLE in the Indian Health Service (IHS) active clinical population in 3 regions of the US.
  
  
  METHODS
  For this population-based registry within the IHS, the denominator consisted of individuals in the IHS active clinical population in 2007, 2008, and/or 2009 and residing in a community in 1 of 3 specified regions. Potential SLE cases were identified based on the presence of a diagnostic code for SLE or related disorder in the IHS National Data Warehouse. Detailed medical record abstraction was performed for each potential case. The primary case definition was documentation in the medical record of ≥4 of the revised American College of Rheumatology criteria for the classification of SLE. Prevalence was calculated for 2007, and the mean annual incidence was calculated for the years 2007 through 2009.
  
  
  RESULTS
  The age-adjusted prevalence and incidence of SLE according to the primary definition were 178 per 100,000 person-years (95% confidence interval [95% CI] 157-200) and 7.4 per 100,000 person-years (95% CI 5.1-10.4). Among women, the age-adjusted prevalence was 271, and the age-adjusted incidence was 10.4. The prevalence was highest in women ages 50-59 years and in the Phoenix Area IHS.
  
  
  CONCLUSIONS
  The first population-based lupus registry in the US American Indian and Alaska Native population has demonstrated that the prevalence and incidence of SLE are high. Our estimates are as high as or higher than the rates reported in the US black population.
authors.affiliation: Alaska Native Tribal Health Consortium, Anchorage.
authors.forename: Elizabeth D
authors.initials: ED
authors.lastname: Ferucci
authors.forename: Janet M
authors.initials: JM
authors.lastname: Johnston
authors.forename: Jasmine R
authors.initials: JR
authors.lastname: Gaddy
authors.forename: Lisa
authors.initials: L
authors.lastname: Sumner
authors.forename: James O
authors.initials: JO
authors.lastname: Posever
authors.forename: Tammy L
authors.initials: TL
authors.lastname: Choromanski
authors.forename: Caroline
authors.initials: C
authors.lastname: Gordon
authors.forename: S Sam
authors.initials: SS
authors.lastname: Lim
authors.forename: Charles G
authors.initials: CG
authors.lastname: Helmick
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000413:Alaska / Q000453:epidemiology; D005260:Female; D006801:Humans; D015994:Incidence; D007198:Indians, North American / Q000706:statistics & numerical data*; D008180:Lupus Erythematosus, Systemic / Q000208:ethnology*; D008875:Middle Aged; D015995:Prevalence; D012042:Registries; D012737:Sex Factors; D014481:United States / Q000453:epidemiology