Large population study in liver stiffness measurement: prevalence of significant fibrosis and correlation with Liver Biochemistry in Chronic Hepatitis B

Abstract

Background and Aim: The prevalence of fibrosis in a large population of chronic hepatitis B (CHB) patients is not known. The aim ofthis study was to investigate the prevalence of significant fibrosis in a Chinese population with CHB by liver stifness measurement (LSM), and its correlation with liver biochemistry and demographic factors. Methods: All CHB patients seen at Hepatitis Clinic, Queen Mary Hospital, Hong Kong for CHB between January to July 2006 with LSM by transient elastography were included. Results: Of the 898 patients included with a median age of 44, 323 (36%) had significant fibrosis as defined by LSM of >8. 1 kPa. Males had a higher median liver stithess measurement (MLSM) than females (7.3 vs 5.9 kPa, p 0.001), and those positive for HBeAg had higher MLSM than HBeAgnegative patients (7.3 and 6.4kPa respectively, p = 0.017). In patients <25, 26-35, 36-45, 46-55, 56-65, and >65 years of age, the MLSM was 6.0, 6.0, 6.4, 7.6, 8.7and 11.6kPa respectively (p <0.001), with 56% of those aged over 55 years having significant fibrosis. LSM scores correlated well with serum bilirubin, ALT, AFP, and albumin levels (all p i 0.001). In patients with ALT i 0.5 upper limit of normal (ULN), 0.5-1 x ULN, I-~xULN, 2-5xULN and >5xULN, the MLSM was 5.7, 6.7, 8.4, 11.7 and 19.1 kPa respectively (p i 0.001). After multivariate analysis, age, bilirubin, ALT, albumin and gender remained significant factors associated with significant fibrosis. Using a combination of serum ALT, bilirubin and albumin levels to predict the presence of significant fibrosis, the sensitivity and specificity were 19% and 98% respectively, with positive predictive value of 84% and negative predictive value of 96%. Conclusion: The prevalence of significant fibrosis in Chinese CHB patients was high, affecting more than half of the patients over the age of 55 years. LSM correlated well with known factors associated with more severe disease, including older age, male sex, higher bilirubin and ALT, and lower albumin. The combination of serum bilirubin, ALT and albumin levels may be used to predict significant underlying fibrosis.