Role of Serum M2BPGi Levels in Predicting Persistence of Advanced Fibrosis in Chronic Hepatitis B Virus Infection

Background Serum mac-2-binding protein glycosylation isomer (M2BPGi) is a novel marker for liver fibrosis assessment in patients with different liver diseases. For chronic hepatitis B infection (CHB), advanced fibrosis or cirrhosis is a risk factor for liver cancer and hepatic decompensation. We aimed to assess the role of serum M2BPGi in prediction of persistence of advanced fibrosis in CHB patients despite potent antiviral therapy. Methods CHB patients with advanced fibrosis or cirrhosis who were put on nucleos(t)ide analogs for >= 3 years with normal alanine aminotransferase and undetectable serum HBV DNA were prospectively recruited. Assessment of liver fibrosis with transient elastography (TE) and M2BPGi measurements were performed at baseline and repeated at 3 years. Advanced fibrosis and cirrhosis were defined by liver stiffness (LS) >= 9.0 kPa and >= 12.0 kPa, respectively. Results A total of 143 patients (M:F = 101:42; median age 58.7 years; 53.8% cirrhotic) were recruited and completed paired assessment. The median value of baseline LS and M2BPGi were 12.0 (IQR: 10.5-18.2) kPa and 0.99 cut-off-index (IQR: 0.75-1.74) (COI), respectively, with 96% concordance for diagnosing F3/F4. Ninety-six (67.1%) patients had persistent advanced fibrosis or cirrhosis at 3 years despite continuation of long-term antiviral treatment. Upon multivariate analysis, baseline M2BPGi (OR 2.128, 95% CI 1.037-4.366) and presence of central obesity (OR 4.648, 95% CI 1.742-12.402) were significantly associated with persistent advanced fibrosis or cirrhosis at 3 years. Baseline M2BPGi >= 1.265 COI has 50.6% sensitivity and 79.4% specificity for predicting persistent advanced fibrosis or cirrhosis at 3 years (area under the receiver-operating characteristic curve: 0.695). The presence of central obesity in combination with baseline M2BPGi >= 1.265 COI was associated with 95.7% patients having persistent advanced fibrosis or cirrhosis at 3 years. HCC development was observed in five patients during follow-up and was associated with bigger median increase in the level of serum M2BPGi compared to patients without HCC (46% vs 6.2%, P = 0.038). Conclusion Persistent advanced fibrosis or cirrhosis was observed in two-thirds of CHB patients despite potent antiviral therapy. High serum M2BPGi and central obesity were associated with more than twofold and fourfold increase in risk of persistent advanced fibrosis or cirrhosis, respectively.