title: Antioxidant supplements for liver diseases.
abstract: BACKGROUND
  Several liver diseases have been associated with oxidative stress. Accordingly, antioxidants have been suggested as potential therapeutics for various liver diseases. The evidence supporting these suggestions is equivocal.
  
  
  OBJECTIVE
  To assess the benefits and harms of antioxidant supplements for patients with liver diseases.
  
  
  METHODS
  We searched The Cochrane Library, MEDLINE, EMBASE, LILACS, the Science Citation Index Expanded, and Conference Proceedings Citation Index-Science to January 2011. We scanned bibliographies of relevant publications and asked experts and pharmaceutical companies for additional trials.
  
  
  METHODS
  We considered for inclusion randomised trials that compared antioxidant supplements (beta-carotene, vitamin A, C, E, and selenium) versus placebo or no intervention for autoimmune liver diseases, viral hepatitis, alcoholic liver disease, and cirrhosis (any aetiology).
  
  
  METHODS
  Four authors independently selected trials for inclusion and extracted data. Outcome measures were all-cause mortality, liver-related mortality, liver-related morbidity, biochemical indices at maximum follow-up in the individual trials as well as adverse events, quality-of-life measures, and cost-effectiveness. For patients with hepatitis B or C we also considered end of treatment and sustained virological response. We conducted random-effects and fixed-effect meta-analyses. Results were presented as relative risks (RR) or mean differences (MD), both with 95% confidence intervals (CI).
  
  
  RESULTS
  Twenty randomised trials with 1225 participants were included. The trials assessed beta-carotene (3 trials), vitamin A (2 trials), vitamin C (9 trials), vitamin E (15 trials), and selenium (8 trials). The majority of the trials had high risk of bias and showed heterogeneity. Overall, the assessed antioxidant supplements had no significant effect on all-cause mortality (relative risk [RR] 0.84, 95% confidence interval [CI] 0.60 to 1.19, I(2) = 0%), or liver-related mortality (RR 0.89, 95% CI 0.39 to 2.05, I(2) = 37%). Stratification according to the type of liver disease did not affect noticeably the results. Antioxidant supplements significantly increased activity of gamma glutamyl transpeptidase (MD 24.21 IU/l, 95% CI 6.67 to 41.75, I(2) = 0%).
  
  
  CONCLUSIONS
  We found no evidence to support or refute antioxidant supplements in patients with liver disease. Antioxidant supplements may increase liver enzyme activity.
authors.affiliation: Cochrane Hepato-Biliary Group, Copenhagen Trial Unit, Centre for Clinical Intervention Research, Department 3344, Rigshospitalet, Copenhagen University Hospital, and Department of Internal Medicine - Gastroenterology and Hepatology, Medical Faculty, University of Nis, Zorana Djindjica 81, Nis, Serbia, 18000.
authors.forename: Goran
authors.initials: G
authors.lastname: Bjelakovic
authors.forename: Lise Lotte
authors.initials: LL
authors.lastname: Gluud
authors.forename: Dimitrinka
authors.initials: D
authors.lastname: Nikolova
authors.forename: Marija
authors.initials: M
authors.lastname: Bjelakovic
authors.forename: Aleksandar
authors.initials: A
authors.lastname: Nagorni
authors.forename: Christian
authors.initials: C
authors.lastname: Gluud
mesh_terms: D000975:Antioxidants / Q000627:therapeutic use*; D001205:Ascorbic Acid / Q000627:therapeutic use; D002423:Cause of Death; D019587:Dietary Supplements; D006801:Humans; D008107:Liver Diseases / Q000188:drug therapy* / Q000401:mortality; D018384:Oxidative Stress; D016032:Randomized Controlled Trials as Topic; D012643:Selenium / Q000627:therapeutic use; D014801:Vitamin A / Q000627:therapeutic use; D014810:Vitamin E / Q000627:therapeutic use; D019207:beta Carotene / Q000627:therapeutic use
chemical_list: D000975:Antioxidants; D019207:beta Carotene; D014801:Vitamin A; D014810:Vitamin E; D012643:Selenium; D001205:Ascorbic Acid