A new model using routinely available clinical parameters to predict significant liver fibrosis in chronic hepatitis B

PLoS One. 2011;6(8):e23077. doi: 10.1371/journal.pone.0023077. Epub 2011 Aug 11.

Abstract

Objective: We developed a predictive model for significant fibrosis in chronic hepatitis B (CHB) based on routinely available clinical parameters.

Methods: 237 treatment-naïve CHB patients [58.4% hepatitis B e antigen (HBeAg)-positive] who had undergone liver biopsy were randomly divided into two cohorts: training group (n = 108) and validation group (n = 129). Liver histology was assessed for fibrosis. All common demographics, viral serology, viral load and liver biochemistry were analyzed.

Results: Based on 12 available clinical parameters (age, sex, HBeAg status, HBV DNA, platelet, albumin, bilirubin, ALT, AST, ALP, GGT and AFP), a model to predict significant liver fibrosis (Ishak fibrosis score ≥3) was derived using the five best parameters (age, ALP, AST, AFP and platelet). Using the formula log(index+1) = 0.025+0.0031(age)+0.1483 log(ALP)+0.004 log(AST)+0.0908 log(AFP+1)-0.028 log(platelet), the PAPAS (Platelet/Age/Phosphatase/AFP/AST) index predicts significant fibrosis with an area under the receiving operating characteristics (AUROC) curve of 0.776 [0.797 for patients with ALT <2×upper limit of normal (ULN)] The negative predictive value to exclude significant fibrosis was 88.4%. This predictive power is superior to other non-invasive models using common parameters, including the AST/platelet/GGT/AFP (APGA) index, AST/platelet ratio index (APRI), and the FIB-4 index (AUROC of 0.757, 0.708 and 0.723 respectively). Using the PAPAS index, 67.5% of liver biopsies for patients being considered for treatment with ALT <2×ULN could be avoided.

Conclusion: The PAPAS index can predict and exclude significant fibrosis, and may reduce the need for liver biopsy in CHB patients.

MeSH terms

  • Adolescent
  • Adult
  • Area Under Curve
  • Cohort Studies
  • Female
  • Hepatitis B, Chronic / complications*
  • Hepatitis B, Chronic / diagnosis*
  • Humans
  • Liver Cirrhosis / complications*
  • Liver Cirrhosis / diagnosis*
  • Male
  • Middle Aged
  • Models, Biological*
  • Predictive Value of Tests
  • ROC Curve
  • Reproducibility of Results
  • Young Adult