title: Hepatic steatosis in hepatitis B virus infected patients: meta-analysis of risk factors and comparison with hepatitis C infected patients.
abstract: OBJECTIVE
  Although hepatic steatosis (HS) has an association with hepatitis C virus (HCV) infection, an association with hepatitis B virus (HBV) is controversial. We performed a meta-analysis to evaluate HS prevalence and risk factors, in HBV infection.
  
  
  METHODS
  Standard guidelines for performance of meta-analyses were followed. Studies with HS assessed by histology were included. Pooled odd ratios (OR) and standardized mean differences (SMD) were obtained with the random-effects model and DerSimonian-Laid method.
  
  
  RESULTS
  Seventeen out of 21 studies were included, comprising 4100 HBV infected patients. Overall HS prevalence was 29.6%. Eight studies also included 945 HCV infected patients, showing decreased risk of HS in HBV versus HCV patients (OR 0.55, 95%CI [0.45-0.67], P < 0.001). In HBV, HS positively associated with male gender (OR 1.74, 95%CI [1.28-2.38], P < 0.001), body mass index (SMD 2.17, 95%CI [1.23, 3.11], P < 0.001), obesity (OR 6.59, 95%CI [3.51-12.257], P = 0.003), diabetes (OR 2.62, 95%CI [1.37-4.00], P = 0.004), glycemia (SMD 0.84, 95%CI [0.00, 1.67], P = 0.049), triglycerides (SMD 1.18, 95%CI [0.48, 1.89], P = 0.001), cholesterol (SMD 0.88, 95%CI [0.31, 1.45], P = 0.003), moderate alcohol consumption (OR 1.54, 95%CI [1.10-2.15], P = 0.011) and negatively with HBV DNA (SMD -74.12, 95%CI [-82.93, -65.31], P < 0.001). HS had no association with aminotransferases, HBeAg, genotype or hepatic histology, necroinflammation or fibrosis.
  
  
  CONCLUSIONS
  HS in HBV seems to be as frequent as in the general population, and lower than in HCV infected patients, relating to metabolic factors but not with hepatic histology severity. A puzzling strong negative association between viral load and HS, may even suggest a protective effect of the virus on HS.
authors.affiliation: Department of Gastroenterology, Nutrition and Metabolism Unit, University Hospital of Santa Maria, Lisbon, Portugal.
authors.forename: Mariana V
authors.initials: MV
authors.lastname: Machado
authors.forename: António G
authors.initials: AG
authors.lastname: Oliveira
authors.forename: Helena
authors.initials: H
authors.lastname: Cortez-Pinto
mesh_terms: D000328:Adult; D005234:Fatty Liver / Q000453:epidemiology / Q000821:virology*; D005260:Female; D019694:Hepatitis B, Chronic / Q000150:complications* / Q000175:diagnosis / Q000453:epidemiology; D019698:Hepatitis C, Chronic / Q000150:complications* / Q000175:diagnosis / Q000453:epidemiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D015995:Prevalence; D018570:Risk Assessment; D012307:Risk Factors; D019562:Viral Load; D055815:Young Adult