title: Hepatitis B and C virus infection among 1.2 million persons with access to care: factors associated with testing and infection prevalence.
abstract: BACKGROUND
  Little is known about viral hepatitis testing and infection prevalence among persons in private healthcare organizations (HCOs) in the United States.
  
  
  METHODS
  To determine the frequency of and characteristics associated with viral hepatitis testing and infection prevalence among adults with access to care, we conducted an observational cohort study among 1.25 million adults from 4 US HCOs and included persons with ≥1 clinical encounter during 2006-2008 and ≥12 months of continuous follow-up before 2009. We compared the number of infections identified with the number expected based on adjusted data from the National Health and Nutrition Examination Survey (NHANES).
  
  
  RESULTS
  Of 866,886 persons without a previous hepatitis B virus (HBV) diagnosis, 18.8% were tested for HBV infection, of whom 1.4% tested positive; among 865,659 without a previous hepatitis C virus (HCV) diagnosis, 12.7% were tested, of whom 5.5% tested positive. Less than half of those with ≥2 abnormal alanine aminotransferase (ALT) levels were subsequently tested for HBV or HCV. When tested, Asians (adjusted odds ratio [aOR] 6.33 relative to whites) were most likely HBV infected, whereas those aged 50-59 years were most likely HCV infected (aOR 6.04, relative to age <30 years). Based on estimates from NHANES, nearly one-half of HCV and one-fifth of HBV infections in this population were not identified.
  
  
  CONCLUSIONS
  Even in this population with access to care and lengthy follow-up, only a fraction of expected viral hepatitis infections were identified. Abnormal ALT levels often but not consistently triggered testing. These findings have implications for the identification and care of 4-5 million US residents with HBV and HCV infection.
authors.affiliation: Division of Viral Hepatitis, Centers for Disease Control and Prevention, Atlanta, Georgia 30333, USA. pspradling@cdc.gov
authors.forename: Philip R
authors.initials: PR
authors.lastname: Spradling
authors.forename: Loralee
authors.initials: L
authors.lastname: Rupp
authors.forename: Anne C
authors.initials: AC
authors.lastname: Moorman
authors.forename: Mei
authors.initials: M
authors.lastname: Lu
authors.forename: Eyasu H
authors.initials: EH
authors.lastname: Teshale
authors.forename: Stuart C
authors.initials: SC
authors.lastname: Gordon
authors.forename: Cynthia
authors.initials: C
authors.lastname: Nakasato
authors.forename: Joseph A
authors.initials: JA
authors.lastname: Boscarino
authors.forename: Emily M
authors.initials: EM
authors.lastname: Henkle
authors.forename: David R
authors.initials: DR
authors.lastname: Nerenz
authors.forename: Maxine M
authors.initials: MM
authors.lastname: Denniston
authors.forename: Scott D
authors.initials: SD
authors.lastname: Holmberg
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006509:Hepatitis B / Q000175:diagnosis* / Q000453:epidemiology*; D006526:Hepatitis C / Q000175:diagnosis* / Q000453:epidemiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D016017:Odds Ratio; D015995:Prevalence; D012189:Retrospective Studies; D014481:United States / Q000453:epidemiology