Rapid decline of noninvasive fibrosis index values in patients with hepatitis C receiving treatment with direct-acting antiviral agents

Background Studies on temporal changes in noninvasive fibrosis indices and liver stiffness measurement (LSM) in patients with chronic hepatitis C (CHC) treated with direct-acting antiviral agents (DAAs) are limited. Methods We retrospectively enrolled consecutive patients with CHC who had received DAAs. Results In total, we recruited 395 consecutive patients, of which 388 (98.2%) achieved a sustained virologic response (SVR) at 12 weeks after therapy. In patients who received DAA therapy and achieved SVR 12 weeks after therapy ( n = 388), the median aspartate aminotransferase/platelet ratio index (APRI) value decreased from 1.19 (0.62–2.44) at baseline to 0.50 (0.32–0.95), 0.51 (0.31–0.92), 0.48 (0.31–0.88), and 0.52 (0.33–0.92) at week 2, week 4, end of therapy, and PW12, respectively (all P < 0.001). The median FIB-4 value decreased from 2.88 (1.56–5.60) at baseline to 2.10 (1.30–3.65), 2.15 (1.30–3.65), 2.11 (1.37–3.76), and 2.22 (1.45–3.82) at week 2, week 4, end of therapy, and PW12, respectively (all P < 0.001). The median alanine aminotransferase level significantly decreased from week 2 until PW12 (all P < 0.001). The platelet count significantly increased from 2 weeks after DAA therapy initiation until PW12 (all P < 0.001); however, the magnitude of changes in the platelet count was low. In patients with paired LSMs obtained using acoustic radiation force impulse elastography at baseline and PW12 ( n = 199), the median LSM decreased from 1.78 (1.25–2.30) m/s at baseline to 1.38 (1.14–1.88) m/s at PW12 ( P < 0.001). Conclusions Noninvasive fibrosis indices, namely APRI and FIB-4, exhibited a rapid and sustained decline from week 2 until PW12 in patients with CHC who achieved SVR to DAA therapy. The rapid decline in APRI and FIB-4 values might mainly result from improvement in necroinflammation.