Liver transplantation for non-alcoholic steatohepatitis in Europe: Where do we stand?

Epidemiology of liver transplantation and post-LT complications in Germany: nationwide study (2005-2018)

BACKGROUND

To date, liver transplantation (LT) is the only curative treatment for cirrhosis and early-diagnosed progressive acute liver failure (ALF). However, LT results in morbidities and mortality even post-LT. Different comorbidities may follow and further increase mortality and morbidity. In this study, we investigated the outcomes and their trends over a period of 14 years among hospitalized patients evaluated for LT, transplant and post-LT in Germany.

METHODS

This German nationwide study investigated the number of admissions of patients hospitalized for evaluation of LT and post-LT on related comorbidities and complications between 2005 and 2018 based on the DRG system with ICD-10/OPS codes. 14 745 patients were put on the LT waiting list and 12 836 underwent LT during the observational period.

RESULTS

The LT number decreased by 2.3% over time, while the waiting list mortality rate increased by 5%. By contrast, the in-hospital mortality rate decreased by 3%, especially in ALF patients (decrease of 16%). Interestingly, admissions of post-LT patients for complications almost doubled, driven mainly by complications of immunosuppression (tripled). Importantly, post-LT patients with acute kidney injury (20.2%) and biliodigestive anastomosis (18.4%) showed the highest in-hospital mortality rate of all complications.

CONCLUSION

In conclusion, the decrease in LT leads most probably to the increased in-hospital mortality of patients on the waiting list. Interestingly, in-hospital mortality decreased in LT patients. Post-LT comorbidities requiring hospitalization increased in the observational period and management of patients post-LT with AKI or biliodigestive anastomosis should be addressed.

Ultrasound-based hepatic fat quantification: current status and future directions

Non-alcoholic fatty liver disease (NAFLD) is a spectrum of disease from fatty accumulation (steatosis), necro-inflammation though to fibrosis. It is of increasing global prevalence as a hepatic manifestation of the metabolic syndrome. Although accurate histopathology and magnetic resonance imaging techniques for hepatic fat quantification exist, these are limited by invasiveness and availability, respectively. Ultrasonography is potentially ideal for assessing and monitoring hepatic steatosis given the examination is rapid and readily available. Traditional ultrasound methods include qualitative B-mode for imaging markers, such as increased hepatic parenchymal echogenicity compared to adjacent renal cortex are commonplace; however, there is acknowledged significant interobserver variability and they are suboptimal for detecting mild steatosis. Recently quantitative ultrasound metrics have been investigated as biomarkers for hepatic steatosis. These methods rely on changes in backscatter, attenuation, and speed of sound differences encountered in a steatotic liver. Prospective studies using quantitative ultrasound parameters show good diagnostic performance even at low steatosis grades and in NAFLD. This review aims to define the clinical need for ultrasound-based assessments of liver steatosis, to describe briefly the physics that underpins the various techniques available, and to assess the evidence base for the effectiveness of the techniques that are available commercially from various ultrasound vendors.

Extrahepatic morbidities and mortality of NAFLD: an umbrella review of meta-analyses

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) has reached pandemic proportions currently and may contribute to multiple extrahepatic outcomes.

AIM

To comprehensively summarise evidence of associations between NAFLD and risk of extrahepatic outcomes.

METHODS

We conducted an umbrella review. We searched PubMed, Web of Science and Cochrane database from inception to 27 November 2021.

RESULTS

We included 22 meta-analyses with 374 original studies in our analysis. Subjects with NAFLD had an increased risk of mortality, multiple cardiovascular complications, extrahepatic cancers, diabetes and chronic kidney disease (CKD) than those without NAFLD. Excess risks of several other extrahepatic outcomes including hypothyroidism, urolithiasis, gastro-oesophageal reflux disease, gallstones, depression and worse maternal and foetal outcomes were also observed in this population. However, associations were not significant for prostate cancer, female organ genital cancer, haematological cancer, diabetic retinopathy or osteoporotic fracture. The risks of CVD, diabetes and CKD were similar in obese and non-obese patients. Most associations were heterogeneous across regions; significantly, Europeans with NAFLD were more prone to all-cause mortality than North Americans. The certainty of evidence was graded from only very low to moderate as all included studies were observational.

CONCLUSIONS

Patients with NAFLD are at heightened risk of extrahepatic outcomes. However, the certainty of evidence is only from very low to moderate. Further studies at low risk of bias are required to support the evidence and elucidate any causal associations.

Breakthroughs in therapies for NASH and remaining challenges

Initially a condition that received limited recognition and whose clinical impact was controversial, non-alcoholic steatohepatitis (NASH) has become a leading cause of chronic liver disease. Although there are no approved therapies, major breakthroughs, which will be reviewed here, have paved the way for future therapeutic successes. The unmet medical need in NASH is no longer disputed, and progress in the understanding of its pathogenesis has resulted in the identification of many pharmacological targets. Key surrogate outcomes for therapeutic trials are now accepted by regulatory agencies, thus creating a path for drug registration. A set of non-invasive measurements enabled early-stage trials to be conducted expeditiously, thus providing early indications on the biological and possibly clinical actions of therapeutic candidates. This generated efficacy results for a number of highly promising compounds that are now in late-stage development. Intense research aimed at further improving the assessment of histological endpoints and in developing non-invasive predictive biomarkers is underway. This will help improve the design and feasibility of successful trials, ultimately providing patients with therapeutic options that can change the course of the disease.

Hospital Mortality and Current Trends in Liver Transplantation in Germany—a Systematic Analysis of Standardized Hospital Discharge Data, 2008–2017

BACKGROUND

Liver transplantation (LT) has undergone dynamic developments in recent decades. In Germany, the Federal Joint Committee (G-BA) recently tightened the guidelines regarding the minimum number of transplantations a center should perform annually. The aim of the study presented here, was to analyze recent trends in hospital mortality due to LT in Germany.

METHODS

Standardized hospital discharge data (2008-2017) from the Federal Statistical Office of Germany were used to establish hospital mortality after LT and case volume distribution among centers performing <20 LT annually (low volume centers, LVC), 20-49 LT (medium volume centers, MVC), and ≥ 50 LT (high volume centers, HVC).

RESULTS

Data from 9254 LT procedures were evaluated. The annual frequency of LT fell from n = 984 (2008) to n = 747 (2017), and over the same period the hospital mortality for all LT procedures went down from 15.8% to 11.0%. Hospital mortality was associated with age (<16 years: 5.3% to 60-69 years: 17.4%); however, there was no further increase in patients ≥ 70 years (16.5%). Univariate analysis revealed association of increased hospital mortality with liver disease etiology, the necessity for relaparotomy, and prolonged mechanical ventilation. The proportion of LT procedures performed in LVC and MVC increased and that in HVC decreased. LVC had higher hospital mortality than MVC/HVC, but this effect was dependent on patient age and disease etiology.

CONCLUSION

Our study showed that differences in mortality rate after LT among centers (LVC vs. MVC/HVC) were dependent on patient age and disease etiology. This should be taken into account when discussing the overall organization of LT in Germany.

What did the European Liver Transplant Registry bring to liver transplantation?

Since its foundation in 1985, the European Liver Transplant Registry has evolved to become an important tool to monitor the liver transplantation activity in Europe. The vast amount of data collected on 169 473 liver transplantations performed in 153 238 recipients has also resulted in scientific publications. Without doubt, several of these have influenced the daily practice of liver transplantation. This paper gives an overview of the development, the functioning, and the scientific activity of the European Liver Transplant Registry during more than three decades. Indeed, it can be said that the registry helped to advance the practice of liver transplantation not only in Europe but also worldwide.