Application of the HALF index obviates the need for liver biopsy in half of all patients with chronic hepatitis B

Background and Aims: Transient elastography (TE) is useful for predicting the fibrosis stage, but it is unsatisfactory as a substitute for liver biopsy, especially in patients with chronic hepatitis B (CHB). This study was performed to establish a reliable model for predicting significant fibrosis (SF) in patients with CHB. Methods: All CHB patients who were admitted to undergo liver biopsy were enrolled. They were randomly classified into either a training set (n = 139) or a validation set (n = 69). A model for predicting SF was established in the training set and validated in the validation set. Low and high cutoff values (COVs) were chosen for sensitivity >= 99% and specificity >= 99%, respectively. Results: A total of 208 patients were enrolled. Age was 39 +/- 12 years and 149 (71.6%) were men. In the training set, liver stiffness values and serum haptoglobin, apolipoprotein A1, and alpha 2-macroglobulin levels were independent predictors of SF on multivariate analysis. These variables were used to construct a novel model, called the HALF index. The area under the receiver operating characteristics curve of the HALF index for predicting SF was significantly higher than that of TE alone (0.915 vs 0.877, P = 0.010). Using low and high COVs of the HALF index, it appears that approximately half (47.1%) of patients could avoid liver biopsy, with an associated accuracy of 99.0%. Conclusion: A combination of liver stiffness and serum markers identified SF with a high degree of accuracy. Approximately half of all patients with CHB could avoid liver biopsy through the utilization of the HALF index.