Enlargement of the spleen index is a predictor of the occurrence of esophageal varices and hepatocellular carcinoma after administering direct-acting antiviral agents.

Background Direct-acting antiviral agents (DAAs) can eliminate hepatitis C virus at a high rate, although the long-term incidence of portal hypertension and hepatocellular carcinoma (HCC) has not yet been elucidated. In this observational study, we clarified the predictors associated with the incidence of esophageal varices (EVs) and HCC after DAAs treatment based on ultrasound findings and blood examinations. Methods A total of 78 patients treated with DAAs were enrolled in this study. The primary endpoint was to identify the predictors associated with EVs and HCC occurrence using univariate and multivariate analyses. Secondary endpoints were to extract the cutoff values for EVs and HCC occurrence and clarify the changes in liver stiffness (LS), spleen stiffness (SS), spleen index (SI), portal vein flow volume (PVF), and blood examination at 12 weeks after the end of DAAs treatment. Results The mean observation period was 1,402±546 days. SI change (SI after DAAs - SI before DAAs) was a predictor of EVs occurrence in multivariate analysis (p = 0.045). The treatment history of HCC, albumin value before DAAs, and SI change were predictors of HCC occurrence in multivariate analysis (p = 0.002, p = 0.032, and p = 0.009, respectively). LS, SS, PVF, SI, and liver function significantly improved after DAAs treatment. Conclusion Portal hypertension seems to improve after DAAs treatment over a long period. Patients with splenomegaly deterioration after DAAs treatment need to be carefully monitored for the occurrence of EVs and HCC.