Citation: Drácz, B.; Müller, V.; Takács, I.; Hagymási, K.; Dinya, E.; Miheller, P.; Szijártó, A.; Werling, K. Effectiveness of COVID-19 Vaccination with mRNA Vaccines for Patients with Cirrhosis in Hungary: Multicentre Matched Cohort Study. Vaccines 2023, 11, 50. https://doi.org/10.3390/ vaccines11010050 Academic Editor: Francesco Paolo Bianchi Received: 26 November 2022 Revised: 22 December 2022 Accepted: 23 December 2022 Published: 26 December 2022 Copyright: © 2022 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/). Article Effectiveness of COVID-19 Vaccination with mRNA Vaccines for Patients with Cirrhosis in Hungary: Multicentre Matched Cohort Study Bálint Drácz 1, * , Veronika Müller 2 , István Takács 3 , Krisztina Hagymási 1 , Elek Dinya 4 ,Pál Miheller 1 , Attila Szijártó 1 and Klára Werling 1 1 Department of Surgery, Transplantation and Gastroenterology, Semmelweis University, 1083 Budapest, Hungary 2 Department of Pulmonology, Semmelweis University, 1083 Budapest, Hungary 3 Department of Internal Medicine and Oncology, Semmelweis University, 1083 Budapest, Hungary 4 Digital Health Department, Semmelweis University, 1083 Budapest, Hungary * Correspondence: balint.dracz@gmail.com Abstract: Patients with cirrhosis are vulnerable to hepatic decompensation events and death following COVID-19 infection. Therefore, primary vaccination with COVID-19 vaccines is fundamental to reducing the risk of COVID-19 related deaths in patients with cirrhosis. However, limited data are available about the effectiveness of mRNA vaccines compared to other vaccines. The aim of our study was to investigate the efficacy of mRNA vaccines versus other vaccines in cirrhosis. In this retrospective study, we compared clinical characteristics and vaccine effectiveness of 399 COVID-19 patients without cirrhosis (GROUP A) to 52 COVID-19 patients with cirrhosis (GROUP B). 54 hospitalised cirrhosis controls without COVID-19 (GROUP C) were randomly sampled 1:1 and matched by gender and age. Of the cirrhosis cases, we found no difference (p = 0.76) in mortality rates in controls without COVID-19 (11.8%) compared to those with COVID-19 (9.6%). However, COVID-19 patients with cirrhosis were associated with higher rates of worsening hepatic encephalopathy, ascites and esophageal varices. Patients with cirrhosis receiving mRNA vaccines had significantly better survival rates compared to viral vector or inactivated vaccines. Primary vaccination with the BNT162b2 vaccine was the most effective in preventing acute hepatic decompensating events, COVID-19 infection requiring hospital admission and in-hospital mortality. Keywords: liver cirrhosis; COVID-19 vaccination; mRNA vaccines; vaccine effectiveness 1. Introduction Severe acute respiratory syndrome (SARS-CoV-2) causing COVID-19 disease has emerged as a pandemic around the globe. Although comorbid conditions such as diabetes, hypertension, chronic lung diseases (particularly COPD), chronic kidney disease and car- diovascular disease have been reported as major risk factors for COVID-19 mortality, the prognostic value of chronic liver disease (in particular liver cirrhosis) is still undefined [1,2]. However, patients with cirrhosis following SARS-CoV-2 infection proved to be at a higher risk for poor outcomes. Registry data showed that overall mortality in patients with cirrho- sis following COVID-19 infection ranged from 16% to 42% and poor outcome increased stepwise with the severity of cirrhosis [2–5]. Furthermore, patients with decompensated cirrhosis following SARS-CoV-2 infection were more susceptible to Intensive Care Unit (ICU) admission, renal replacement therapy and invasive mechanical ventilation compared to those without chronic liver disease (CLD) [6]. Acute-on-chronic liver failure (ACLF), which is a life-threatening syndrome, occurred in 12-50% of decompensating patients in COVID-19 infection [2,4,7]. Despite respiratory failure being the leading cause (71%) in COVID-19, liver-related manifestations (19%) are also common [2]. Nevertheless lung Vaccines 2023, 11, 50. https://doi.org/10.3390/vaccines11010050 https://www.mdpi.com/journal/vaccines