Liver Transplantation: the Role of Metabolic Syndrome

Vibration-Controlled Transient Elastography-Based Parameters Predict Clinical Outcomes in Liver Transplant Recipients

BACKGROUND AND AIMS

Vibration-controlled transient elastography (VCTE) is used in clinical practice to risk-stratify liver transplant (LT) recipients; however, there are currently little data demonstrating the relationship between VCTE and clinical outcomes.

METHODS

A total of 362 adult LT recipients with successful VCTE examination between 2015 and 2022 were included. Presence of advanced fibrosis was defined as liver stiffness measurement (LSM) ≥10.5 kPa and hepatic steatosis as controlled attenuation parameter (CAP) ≥270 dB/m. The outcomes of interest included all-cause mortality, myocardial infarction (MI), and graft cirrhosis using cumulative incidence analysis that accounted for the competing risks of these outcomes.

RESULTS

The LSM was elevated in 64 (18%) and CAP in 163 (45%) LT recipients. The baseline LSM values were similar in patients with elevated vs normal CAP values. After a median follow-up of 65 (interquartile range, 20-140) months from LT to baseline VCTE, 66 (18%) patients died, 12 (3%) developed graft cirrhosis, and 18 (5%) experienced an MI. Baseline high LSM was independently associated with all-cause mortality (hazard ratio [HR], 1.97; 95% confidence interval [CI], 1.11-3.50; P = .02) and new onset cirrhosis (HR, 6.74; 95% CI, 2.08-21.79; P < .01). A higher CAP value was significantly and independently associated with increased risk of experiencing a MI over study follow-up (HR, 4.14; 95% CI, 1.29-13.27; P = .017).

CONCLUSIONS

The VCTE-based parameters are associated with clinical outcomes and offer the potential to be incorporated into clinical risk-stratification strategies to improve outcomes among LT recipients.

Evaluation of liver stiffness measurement-based scores in liver transplantation recipients

Combining bioclinical parameters with liver stiffness measurement (LSM) has improved the diagnostic performance of vibration-controlled transient elastography (VCTE) for detection of advanced fibrosis in patients with chronic liver disease. However, this approach has not yet been tested in liver transplantation (LT) recipients. Thus, the aim of this study was to evaluate the diagnostic performance of combining LSM-based scores with LSM alone for the detection of advanced fibrosis in LT recipients. Adult LT recipients with a liver biopsy, VCTE, and clinical data necessary to construct LSM-based fibrosis models (FibroScan-AST [FAST], AGILE-3+, and AGILE-4) were included ( n = 132). The diagnostic statistics for advanced fibrosis (fibrosis stage 0-2 vs. 3-4) were determined by optimal cut-off using the Youden index. The area under the receiver operating characteristic curve (AUROC) for LSM was 0.94 (95% confidence interval [95% CI], 0.89-0.99), FAST was 0.65 (95% CI, 0.50-0.79), AGILE-3+ was 0.90 (95% CI, 0.83-0.97), and AGILE-4 was 0.90 (95% CI, 0.83-0.97). No statistically significant differences were noted between the AUROC of LSM versus LSM-based scores. The false-positive rates for AGILE-3+ and AGILE-4 were 14.5% and 11.8% compared with 8.3% for LSM alone. The false-positive rates in LSM-based scores were higher among patients with diabetes mellitus, higher AST levels, and lower platelet counts. The LSM-based scores did not improve the diagnostic performance of LSM alone in LT recipients for the detection of advanced fibrosis. This lack of improvement in diagnostic performance results from the impact of immunosuppression on bioclinical profile and underscores the importance of developing LSM-based scores that are specific to LT patients.

Clinical evidence of outcomes following liver transplantation in patients with nonalcoholic steatohepatitis: An updated meta-analysis and systematic review

OBJECTIVE

Nonalcoholic steatohepatitis (NASH) is a dramatically growing indication for liver transplantation (LT) worldwide and the posttransplant outcomes of NASH patients are currently under intensive investigation. This quantitative meta-analysis aimed to update the clinical evidence on outcomes of transplanted patients with NASH.

METHODS

We performed a systematic review and meta-analysis of studies (published up to September 15, 2021) that focused on LT outcomes for NASH versus non-NASH patients. Random-effect meta-analysis was conducted to calculate pooled odds ratios (ORs) and 95% confidence intervals (CIs). Subgroup analyses based on crucial baseline clinical characteristics and leave-one-out sensitivity analyses were conducted to assess the robustness of the pooled results. Meta-regression was used to evaluate study-level demographic, clinical, and biochemical characteristics to identify potential confounders affecting patient survival.

RESULTS

Twenty-two non-randomized comparative studies with 1,538 NASH and 6,014 non-NASH patients were included. 1- (OR, 0.94; 95% CI, 0.77-1.14), 3- (OR, 0.82; 95% CI, 1.00-1.22), and 5- (OR, 1.05; 95% CI, 0.84-1.31) year patient survival was equivalent between NASH and non-NASH recipients. NASH patients were associated with similar cardiovascular mortality (OR, 1.36; 95% CI, 0.89-2.09) and retransplantation rates (OR, 0.69; 95% CI, 1.03-1.53), lower graft failure-related mortality (OR, 0.11; 95% CI, 0.29-0.74), but higher sepsis-related mortality (OR, 1.53; 95% CI, 1.13-2.06). Meta-regression revealed that a higher proportion of patients with hepatocellular carcinoma (HCC) were associated with significantly superior overall patient survival at 1 (P = 0.044), 3 (P = 0.035) and 5 (P = 0.049) years after LT in NASH compared with non-NASH.

CONCLUSIONS

This study shows no difference in posttransplant survival between NASH and non-NASH patients. Carefully selected patients with NASH-related HCC may benefit from LT. NASH recipients should be managed with caution posttransplant, especially regarding the potentially high risk of sepsis-related death.

Metabolic syndrome before liver transplantation: does it have an impact on post liver transplantation outcomes?

INTRODUCTION

Metabolic syndrome (MS) and cardiovascular risk factors are commonin liver transplant (LT) candidates and recipients. Cardiovascular events and de novo tumours are increasingly common causes of mortality in liver transplant recipients. The aim of this study is (i) to assess the prevalence of MS in LT recipients and its growth over the years and (ii) if the presence of MS pre-LT is associated with a higher risk of post-LT cardiovascular events (CVE), de novo tumours or early and late survival.

PATIENTS AND METHODS

Retrospective study that included LT recipients from January 2012 to December 2017. Baseline features (MS before LT and at 1year post-LT) and outcomes (CVE, de novo tumours and survival) were recorded.

RESULTS

483 recipients were included, MS was present pre-LT in 20% with an increasing prevalence over time, from16% in 2012 to 34% in 2017 (p=0.025). One-year post-LT, an additional 12% had developed de novo MS .At a median of 56-months follow-up, 13% developed a CVE and 9% a de novo tumour. One and 5-yr survival rates were91% and 83 % in those with pre-LT MS and 93% and 85 % in those without (p=0.94).The presence of MS before LT was independently associated with a higher risk of post-LT CVE (HR: 2.66 IC (95%): 1.6-4.4 p< 0.001), but not with de novo tumors (p=0.94) nor early and late survival (p=0.58 and p=0.87).

CONCLUSION

Pre-LT MS is increasing among LT candidates and is associated with a higher risk of post-LT morbidity CVE yet without affecting mortality.

Metabolic syndrome and liver disease in the era of bariatric surgery: What you need to know!

Metabolic syndrome (MS) is defined as the constellation of obesity, insulin resistance, high serum triglycerides, low high-density lipoprotein cholesterol, and high blood pressure. It increasingly affects more and more people and progressively evolves into a serious issue with widespread healthcare, cost, and quality of life associated consequences. MS is associated with increased morbidity and mortality due to cardiovascular or chronic liver disease. Conservative treatment, which includes diet, exercise, and antidiabetic agents, is the mainstay of treatment, but depends on patient compliance to medical treatment and adherence to lifestyle modification recommendations. Bariatric surgery has recently emerged as an appropriate alternative treatment with promising long-term results. Sleeve gastrectomy and Roux-en-Y gastric bypass constitute the most commonly performed procedures and have been proven both cost-effective and safe with low complication rates. Liver transplantation is the only definitive treatment for end-stage liver disease and its utilization in patients with non-alcoholic steatohepatitis has increased more than fivefold over the past 15 years. In this review, we summarize current state of evidence on the surgical treatment of MS.

Expert consensus on management of metabolic disease in Chinese liver transplant recipients

Metabolic disease, including diabetes mellitus, hypertension, dyslipidemia, obesity, and hyperuricemia, is a common complication after liver transplantation and a risk factor for cardiovascular disease and death. The development of metabolic disease is closely related to the side effects of immunosuppressants. Therefore, optimization of the immunosuppressive regimen is very important for the prevention and treatment of metabolic disease. The Chinese Society of Organ Transplantation has developed an expert consensus on the management of metabolic diseases in Chinese liver transplant recipients based on recent studies. Emphasis is placed on the risk factors of metabolic diseases, the effect of immunosuppressants on metabolic disease, and the prevention and treatment of metabolic diseases.

Managing diabetes and liver disease association

There is strong association between liver diseases and diabetes (DM) which is higher than expected by a chance association of two very common disorders. It can be classified into three categories: Liver disease related to diabetes, hepatogenous diabetes (HD), and liver disease occurring coincidentally with DM. The criteria for the diagnosis of diabetes associating liver disease are the same for primary diabetes. Two hours post glucose load is a better screening test for HD. HbA1c may not be suitable for diagnosis or monitoring of diabetes associating advanced liver disease. Apart from the increased cardiovascular risk in patients with type 2 DM (T2 DM) and NAFLD, the cardiovascular and retinopathy risk is low in HD. Patients with metabolic derangement should be screened for NAFLD which in turn may predict T2 DM development. Similarly, patients with established T2 DM should also be screened for NAFLD which further contributes to diabetes worsening. Diabetes is a significant risk factor for progression of the chronic liver disease. It is associated with poor patient survival. Treatment of diabetes associating liver disease appears beneficial. Metformin, if tolerated and not contraindicated, is recommended as a first-line therapy for patients with diabetes and chronic liver disease (CLD). If the hepatic disease is severe, insulin secretagogues should be avoided because of the increased risk of hypoglycaemia. Pioglitazone may be useful in patients with fatty liver disease. DPP-4 inhibitors showed effectiveness and safety for the treatment of T2 DM in CLD patients up to those with child B stage. GLP-1 receptor agonists and SGLT-2 inhibitors exhibit positive effects on weight and are associated with minimal risk of hypoglycaemia. Insulin must be used with caution, as hypoglycaemia may be a problem. Insulin analogues are preferred in the context of hypoglycaemia Statins can be used to treat dyslipidaemia in NAFLD, also the use of angiotensin II receptor antagonist for hypertension is safe and beneficial Given the clear association between diabetes mellitus and hepatocellular carcinoma, the strict control of glycaemia with insulin sensitizers can be essential in its prevention. The addition of DM to the currently used scores (Child-Pugh and MELD scores) may enhance the sensitivity and the specificity for prediction of morbidity and mortality rates in cirrhotic patients. In the new era of directly acting antiviral agents (DAAs) for HCV treatment, it is recommended to follow up lipid profile and blood sugar levels following SVR in order to adjust doses of medications used in diabetic (SVR is associated with reduction in insulin requirements) and dyslipidaemic patients (rebound increase in the lipid profile after clearing the virus may increase risk of cardiovascular disease (CVD)). The issues of post liver transplant diabetes and relation between DM and chronic HBV are highlighted. This narrative review and Consensus-based practice guidance (under revision and criticism) are based on a formal review and analysis of the recently published world literature on the topic (Medline search up to September 2017); and the experience of the authors and independent reviewers.

Specific issues concerning the management of patients on the waiting list and after liver transplantation

The present document is a second contribution collecting the recommendations of an expert panel of transplant hepatologists appointed by the Italian Association for the Study of the Liver (AISF) concerning the management of certain aspects of liver transplantation, including: the issue of prompt referral; the management of difficult candidates; malnutrition; living related liver transplants; hepatocellular carcinoma; and the role of direct acting antiviral agents before and after transplantation. The statements on each topic were approved by participants at the AISF Transplant Hepatology Expert Meeting organized by the Permanent Liver Transplant Commission in Mondello on 12-13 May 2017. They are graded according to the GRADE grading system.