The informative value of noninvasive tools for assessment of liver fibrosis in chronic hepatitis B patients under antiviral treatment with nucleoside and nucleotide analogues

Background: Antiviral therapy (AVT) with nucleoside and nucleotide analogues (NAs) for chronic hepatitis B (CHB) is aimed at prevention of the development and progression of fibrosis, liver cirrhosis, and hepatocellular carcinoma. Therefore, monitoring of changes in liver fibrosis over time with noninvasive tests is a necessary prerequisite for the assessment of treatment efficacy. However, there are very few studies on changes of transient elastometry (TE) over time, the calculated indices APRI and FIB-4 under AVT in patients with CHB. Aim: To assess changes in noninvasive tests (TE, APRI, FIB-4) over time and to identify factors influencing the fibrosis severity in CHB patients treated with NAs. Materials and methods: This retrospective study was performed in 42 CHB patients, in whom noninvasive methods (TE, APRI and FIB-4) were used before and during NA-based AVT. The patients were divided into two groups: those with a significant reduction in liver density (SRLD, at least by 25% from their baseline TE) and those without a significant reduction ( 25%). Results: Virological response was achieved in 38/42 patients after NA-based AVT (mean duration, 21 months). TE values decreased significantly in the patients with severe fibrosis/cirrhosis (F3/F4) (from 14.2 to 8.3 kPa, p = 0.001), with minimal/moderate fibrosis (F1/F2) (from 5.9 to 5.1 kPa, p = 0.009), and in HBeAg-negative patients (from 6.9 to 5.2 kPa, p 0.001). The F3/F4, F1/F2, HBeAg-positive and HBeAg-negative patients demonstrated a significant reduction in APRI and FIB-4 indices (all p 0.05). Higher baseline TE values were independently associated with SRLD (odds ratio 1.324; 95% confidence interval (CI) 1.0291.702; p = 0.029). Baseline TE, APRI, and FIB-4 values positively correlated with their values on treatment (all p 0.05). The AUROC values of APRI and FIB-4 reduction as SRLD predictors were 0.632 (95% CI 0.4570.807; p = 0.160) and 0.578 (95% CI 0.3910.764; p = 0.408), respectively. Conclusion: NA-based AVT promoted the regression of fibrosis in CHB patients. A high baseline TE value was identified as an independent SRLD predictor. At the same time, despite moderate positive correlations between TE, APRI and FIB-4 parameters, the calculated indexes APRI and FIB-4 cannot be used to predict SRLD. The decrease in liver tissue density by at least 25% correlated only with TE parameters, which makes it possible to recommend TE for monitoring liver fibrosis in CHB patients treated with NA.