Impact of comorbidities on patient outcomes after interferon-free therapy-induced viral eradication in hepatitis C

Abstract

Background & aims: Patients with advanced liver fibrosis remain at risk of cirrhosis-related outcomes and those with severe comorbidities may not benefit from hepatitis C (HCV) eradication. We aimed to collect data on all-cause mortality and relevant clinical events within the first two years of direct-acting antiviral therapy, whilst determining the prognostic capability of a comorbidity-based model.

Methods: This was a prospective non-interventional study, from the beginning of direct-acting antiviral therapy to the event of interest (mortality) or up to two years of follow-up, including 14 Spanish University Hospitals. Patients with HCV infection, irrespective of liver fibrosis stage, who received direct-acting antiviral therapy were used to build an estimation and a validation cohort. Comorbidity was assessed according to Charlson comorbidity and CirCom indexes.

Results: A total of 3.4% (65/1,891) of individuals died within the first year, while 5.4% (102/1,891) died during the study. After adjusting for cirrhosis, platelet count, alanine aminotransferase and sex, the following factors were independently associated with one-year mortality: Charlson index (hazard ratio [HR] 1.55; 95% CI 1.29-1.86; p = 0.0001), bilirubin (HR 1.39; 95% CI 1.11-1.75; p = 0.004), age (HR 1.06 95% CI 1.02-1.11; p = 0.005), international normalized ratio (HR 3.49; 95% CI 1.36-8.97; p = 0.010), and albumin (HR 0.18; 95% CI 0.09-0.37; p = 0.0001). HepCom score showed a good calibration and discrimination (C-statistics 0.90), and was superior to the other prognostic scores (model for end-stage liver disease 0.81, Child-Pugh 0.72, CirCom 0.68) regarding one- and two-year mortality. HepCom score identified low- (≤5.7 points: 2%-3%) and high-risk (≥25 points: 56%-59%) mortality groups, both in the estimation and validation cohorts. The distribution of clinical events was similar between groups.

Conclusions: The HepCom score, a combination of Charlson comorbidity index, age, and liver function (international normalized ratio, albumin, and bilirubin) enables detection of a group at high risk of one- and two-year mortality, and relevant clinical events, after starting direct-acting antiviral therapy.

Lay summary: The prognosis of patients with severe comorbidities may not benefit from HCV viral clearance. An algorithm to decide who will benefit from the treatment is needed to manage the chronic HCV infection better.

Keywords: Charlson index; Comorbidity; Hepatitis C; Survival; Viral eradication.