title: Changing aetiology of liver dysfunction in the new generation of a hepatitis B and C-endemic area: cross-sectional studies on adolescents born in the first 10 years after universal hepatitis B vaccination.
abstract: OBJECTIVE
  Geographical variation in viral hepatitis infection complicates various levels of liver diseases. This study elucidates the changing aetiology of alanine transaminase elevation (ALT levels >40 IU/L) in a previously hepatitis-endemic township.
  
  
  METHODS
  Five cross-sectional screenings were performed on teenagers born from 1984 to 1993. We examined hepatitis B surface antigen (HBsAg), anti-hepatitis C virus (anti-HCV), ALT and body mass index, and additionally checked hepatitis B envelope antigen (HBeAg) for positive HBsAg and HCV RNA for positive anti-HCV. Teenagers with ALT elevation underwent an ultrasonography examination.
  
  
  RESULTS
  This study enrolled 1788 (93.7%) of 1909 students, discovering individual prevalence of HBsAg (6.3%), anti-hepatitis B core (anti-HBc) (15.5%), anti-HCV (2.2%), overweight (22.4%), obesity (12.8%) and ALT >40 IU/L (3.7%). HBsAg and anti-HBc prevalence declined with trends, while obesity increased with trends (P<0.001). Among 66 ALT-elevated teenagers, prevalence percentages of risk factors were HBsAg (22.7%), anti-HCV (1.5%), obesity (45.5%), HBsAg with obesity (7.6%) and anti-HCV with obesity (3.0%). Additionally, obesity showed predominance (85.7%) among aetiologies of teenagers with fatty livers (60.9%). The independently associated factors of ALT elevation included being male (odds ratio, 2.18; 95% confidence interval, 1.21-3.93), HBsAg (4.25; 1.06-17.13), HBeAg (7.24; 1.64-31.9), HCV RNA (29.03; 5.8-145.29) and obesity (16.5; 8.79-30.98).
  
  
  CONCLUSIONS
  In place of viral hepatitis, obesity is becoming the major aetiology of abnormal liver function among the young generation in a previously hepatitis-endemic area.
authors.affiliation: Department of Internal Medicine, Chang Gung Memorial Hospital, Kaohsiung Medical Center, Chang Gung University College of Medicine, Kaohsiung, Taiwan.
authors.forename: Jung-Ta
authors.initials: JT
authors.lastname: Kao
authors.forename: Jing-Houng
authors.initials: JH
authors.lastname: Wang
authors.forename: Chao-Hung
authors.initials: CH
authors.lastname: Hung
authors.forename: Tsung-Hui
authors.initials: TH
authors.lastname: Hu
authors.forename: Chuan-Mo
authors.initials: CM
authors.lastname: Lee
authors.forename: Shu-Fen
authors.initials: SF
authors.lastname: Hung
authors.forename: Sheng-Nan
authors.initials: SN
authors.lastname: Lu
mesh_terms: D000293:Adolescent; D000410:Alanine Transaminase / Q000097:blood*; D015992:Body Mass Index; D002648:Child; D003430:Cross-Sectional Studies; D019353:Endemic Diseases / Q000517:prevention & control*; D005260:Female; D006509:Hepatitis B / Q000453:epidemiology; D017325:Hepatitis B Vaccines; D006526:Hepatitis C / Q000453:epidemiology; D006801:Humans; D008107:Liver Diseases / Q000097:blood / Q000209:etiology*; D008297:Male; D009765:Obesity / Q000097:blood / Q000150:complications*; D015995:Prevalence; D013624:Taiwan / Q000453:epidemiology
chemical_list: D017325:Hepatitis B Vaccines; D000410:Alanine Transaminase