Systemic inflammation increases across distinct stages of advanced chronic liver disease and correlates with decompensation and mortality

Abstract

Background & aims: Distinct prognostic stages of advanced chronic liver disease (ACLD) are defined by severity of portal hypertension (PH) and the presence/absence of clinical complications. We characterised the degree of liver dysfunction, PH, and systemic inflammation across the distinct prognostic stages and assessed their relative impact on decompensation and mortality.

Methods: A single-centre, prospective cohort of ACLD patients undergoing hepatic venous pressure gradient (HVPG) measurement between 01/2017 and 08/2019 were classified into 6 prognostic stages: mild PH (HVPG 6-9 mmHg, S0), clinically significant PH (HVPG ≥10 mmHg without varices, S1), presence of varices (S2), history of variceal bleeding (S3), first non-bleeding decompensation (S4), and further decompensation (S5). The model for end-stage liver disease (MELD), C-reactive protein (CRP), and IL-6 levels were assessed in relation to their predictive value for decompensation and death.

Results: Among 168 ACLD patients 78 had compensated (cACLD, S0 = 13; S1 = 21; S2 = 44) and 90 had decompensated (dACLD, S3 = 10; S4 = 58; S5 = 22) disease. MELD increased across all stages (p <0.001), whereas HVPG mostly increased within cACLD substages. Significant increases in CRP and IL-6 levels were only noted across dACLD substages. IL-6 was an independent predictor of decompensation at 1-year follow-up in cACLD (hazard ratio [HR] 1.06, 95% CI 1.01-1.10; p = 0.013). In dACLD patients, IL-6 levels predicted death/transplantation after 1-year of follow-up (HR 1.02, 95% CI 1.01-1.03; p = 0.004).

Conclusion: HVPG progression occurs mostly in cACLD patients, whereas systemic inflammation, as reflected by IL-6 levels, only increases substantially across dACLD stages. IL-6 levels correlate with the risk of first decompensation in cACLD and of death/transplantation in dACLD patients.

Lay summary: Patients with advanced chronic liver disease (ACLD; i.e. liver cirrhosis) have a certain risk of mortality according to their stage of disease. Progression of disease is greatly influenced by increased pressure in the portal venous system (i.e. portal hypertension) and occurrence of clinical complications (i.e. decompensation). Our study demonstrates that systemic inflammation markedly increases across highest disease stages, and the inflammation biomarker IL-6 in blood may specifically indicate risk of disease progression in patients with ACLD.

Clinical trials registration: The study is registered at ClinicalTrials.gov (NCT03267615).

Keywords: C-reactive protein; Cirrhosis; Interleukin-6; Portal hypertension; Systemic inflammation.