Central role of the β-cell in driving regression of diabetes after liver transplantation in cirrhotic patients

Assessment of hepatic fibrosis with non-invasive indices in subjects with diabetes before and after liver transplantation

Introduction

One of the most common complications of cirrhosis is diabetes, which prevalence is strictly related to severity of hepatopathy. Actually, there are no data on the persistence of post-transplant glucose abnormalities and on a potential impact of diabetes on development of fibrosis in the transplanted liver. To this aim, we evaluated liver fibrosis in cirrhotic subjects before and after being transplanted.

Methods

The study included 111 individuals who had liver transplantation. The assessment was performed before and two years after surgery to investigate a potential impact of the persistence of diabetes on developing de novo fibrosis in the transplanted liver. The degree of fibrosis was assessed using the Fibrosis Index Based on 4 Factors (FIB-4) and the Aspartate to Platelet Ratio Index (APRI).

Results

At pre-transplant evaluation, 63 out of 111 (56.8%) subjects were diabetic. Diabetic subjects had higher FIB-4 (Geometric mean, 95% confidence interval: 9.74, 8.32-11.41 vs 5.93, 4.71-7.46, P<0.001) and APRI (2.04, 1.69-2.47 vs 1.18, 0.90-1.55, P<0.001) compared to non-diabetic subjects. Two years after transplantation, 39 out of 111 (35.1%) subjects remained with diabetes and continued to show significantly higher FIB-4 (3.14, 2.57-3.82 vs 1.87, 1.55-2.27, P<0.001) and APRI (0.52, 0.39-0.69 vs 0.26, 0.21-0.32, P<0.001) compared to subjects without diabetes.

Discussion

Thus, persistence of diabetes after surgery is a possible risk factor for an evolution to fibrosis in the transplanted liver, potentially leading to worsened long-term outcomes in this population.

Effects of Liver Fibrosis on Islet Function in Patients with Chronic Hepatitis B Complicated with Impaired Fasting Glucose

Background

Patients with chronic hepatitis B (CHB) and cirrhosis often have impaired fasting glucose (IFG). This study sought to investigate the impact of liver fibrosis on islet function in individuals diagnosed with CHB and IFG.

Material and Methods

Patients with chronic hepatitis B (CHB) and impaired fasting glucose (IFG) were selected for this study. They were divided into low-risk (L-R), intermediate-risk (M-R), and high-risk (H-R) liver fibrosis groups based on the FIB-4 score. The study compared islet function among different risk groups of liver fibrosis and analyze the correlation between liver fibrosis and islet function. Additionally, the patients were divided into a diabetes mellitus (DM) group and a non-DM (NDM) group based on the development of DM. The cumulative risk of progression to DM in patients with L-R, M-R, and H-R liver fibrosis was analyzed using the Kaplan-Meier method. Hazard ratios (HRs) and confidence intervals (CIs) were calculated for DM development through Cox regression analysis.

Results

In this study of 228 individuals, higher FIB-4 scores were observed in the DM group compared to the NDM group. Patients with H-R liver fibrosis displayed lower islet function and had a significantly higher risk of developing DM. The FIB-4 score and fasting plasma glucose (FPG) were identified as independent risk factors for DM progression in CHB patients with IFG.

Conclusion

Among patients with CHB and IFG, the severity of liver fibrosis is associated with islet function, and the FIB-4 score is a significant risk factor for DM development.

Hepatogenous diabetes: Knowledge, evidence, and skepticism

The diabetogenic potential of liver cirrhosis (LC) has been known for a long time, and the name "hepatogenous diabetes" (HD) was coined in 1906 to define the condition. Diabetes mellitus (DM) that develops as a consequence of LC is referred to as HD. In patients with LC, the prevalence rates of HD have been reported to vary from 21% to 57%. The pathophysiological basis of HD seems to involve insulin resistance (IR) and pancreatic β-cell dysfunction. The neurohormonal changes, endotoxemia, and chronic inflammation of LC initially create IR; however, the toxic effects eventually lead to β-cell dysfunction, which marks the transition from impaired glucose tolerance to HD. In addition, a number of factors, including sarcopenia, sarcopenic obesity, gut dysbiosis, and hyperammonemia, have recently been linked to impaired glucose metabolism in LC. DM is associated with complications and poor outcomes in patients with LC, although the individual impact of each type 2 DM and HD is unknown due to a lack of categorization of diabetes in most published research. In fact, there is much skepticism within scientific organizations over the recognition of HD as a separate disease and a consequence of LC. Currently, T2DM and HD are being treated in a similar manner although no standardized guidelines are available. The different pathophysiological basis of HD may have an impact on treatment options. This review article discusses the existence of HD as a distinct entity with high prevalence rates, a strong pathophysiological basis, clinical and therapeutic implications, as well as widespread skepticism and knowledge gaps.

Impact of CFTR Modulators on Beta-Cell Function in Children and Young Adults with Cystic Fibrosis

Background: To date, no consistent data are available on the possible impact of CFTR modulators on glucose metabolism. The aim of this study was to test the hypothesis that treatment with CFTR modulators is associated with an improvement in the key direct determinants of glucose regulation in children and young adults affected by Cystic Fibrosis (CF). Methods: In this study, 21 CF patients aged 10–25 underwent oral glucose tolerance test (OGTT) before and after 12–18 months of treatment with Lumacaftor/Ivacaftor or Elexacaftor-Ivacaftor-Tezacaftor. β-cell function (i.e., first and second phase of insulin secretion measured as derivative and proportional control, respectively) and insulin clearance were estimated by OGTT mathematical modelling. Insulin sensitivity was estimated by the Oral Glucose Sensitivity Index (OGIS). The dynamic interplay between β-cell function, insulin clearance and insulin sensitivity was analysed by vector plots of glucose-stimulated insulin bioavailability vs. insulin sensitivity. Results: No changes in glucose tolerance occurred after either treatment, whereas a significant improvement in pulmonary function and chronic bacterial infection was observed. Beta cell function and insulin clearance did not change in both treatment groups. Insulin sensitivity worsened in the Lumacaftor/Ivacaftor group. The analysis of vector plots confirmed that glucose regulation was stable in both groups. Conclusions: Treatment of CF patients with CFTR modulators does not significantly ameliorate glucose homeostasis and/or any of its direct determinants.

Safety and Effectiveness Using 8 Weeks of Glecaprevir/Pibrentasvir in HCV-Infected Treatment-Naïve Patients with Compensated Cirrhosis: The CREST Study

Introduction

In clinical trials with hepatitis C virus-infected treatment-naïve (TN) patients with compensated cirrhosis (CC), glecaprevir/pibrentasvir (G/P), a fixed-dose, once-daily, pangenotypic regimen, has demonstrated sustained virologic response at posttreatment Week 12 (SVR12) > 95%. We evaluated the real-world safety and effectiveness of 8-week G/P therapy in TN patients with CC, including certain subgroups of interest.

Methods

The CREST study is a real-world, noninterventional, multicenter study retrospectively assessing data from Canada, Germany, Israel, Italy, and Spain. The full analysis set (FAS) designated all patients in the study; the modified analysis set (MAS) excluded patients who discontinued G/P for nonvirologic failure or who had missing SVR12 data. The primary endpoint was SVR12; safety endpoints were also assessed.

Results

A total of 386 patients were included in the FAS, 375 patients completed the study, and 325 patients were included in the MAS; 51 patients had missing SVR12 data. Overall, in the MAS and FAS, SVR12 was achieved in 99.1% and 84.2% of patients, respectively. In subgroups of interest, the percentage of patients achieving SVR12 in the MAS (and FAS) was: genotype (GT)3: 97.5% (80.6%); FibroScan^® ≥ 12.5 kPa: 98.9% (89.3%); platelet count < 100 × 10⁹/l: 100% (88.2%); both platelets < 150 × 10⁹/l and FibroScan^® > 20 kPa: 100% (88.9%); aspartate aminotransferase-to-platelet ratio index > 1.09: 98.7% (83.1%); fibrosis-4 index > 3.25: 98.6% (84.0%); albumin < 3 g/dl: 100% (91.7%); people who use drugs: 97.7% (84.3%); psychiatric disorders: 96.6% (84.8%); and human immunodeficiency virus coinfection: 100% (95.0%). Overall, 26.9% (104/386) of patients experienced an adverse event, none of which were classed as serious.

Conclusion

In this real-world cohort, 8 weeks of G/P therapy was well tolerated in TN patients with CC. SVR12 rates were similar to clinical trials, supporting 8-week treatment in TN patients with CC, including those with signs of advanced liver disease and GT3 infection.

Management of Diabetes in Candidates for Liver Transplantation and in Transplant Recipients

Diabetes is common in patients waitlisted for liver transplantation because of end-stage liver disease or hepatocellular cancer as well as in posttransplant phase (posttransplantation diabetes mellitus). In both conditions, the presence of diabetes severely affects disease burden and long-term clinical outcomes; careful monitoring and appropriate treatment are pivotal to reduce cardiovascular events and graft and recipients' death. We thoroughly reviewed the epidemiology of diabetes in the transplant setting and the different therapeutic options, from lifestyle intervention to antidiabetic drug use-including the most recent drug classes available-and to the inclusion of bariatric surgery in the treatment cascade. In waitlisted patients, the old paradigm that insulin should be the treatment of choice in the presence of severe liver dysfunction is no longer valid; novel antidiabetic agents may provide adequate glucose control without the risk of hypoglycemia, also offering cardiovascular protection. The same evidence applies to the posttransplant phase, where oral or injectable noninsulin agents should be considered to treat patients to target, limiting the impact of disease on daily living, without interaction with immunosuppressive regimens. The increasing prevalence of liver disease of metabolic origin (nonalcoholic fatty liver) among liver transplant candidates, also having a higher risk of noncirrhotic hepatocellular cancer, is likely to accelerate the acceptance of new drugs and invasive procedures, as suggested by international guidelines. Intensive lifestyle intervention programs remain however mandatory, both before and after transplantation. Achievement of adequate control is mandatory to increase candidacy, to prevent delisting, and to improve long-term outcomes.

High Albumin Level Is Associated With Regression of Glucose Metabolism Disorders Upon Resolution of Acute Liver Inflammation in Hepatitis B-Related Cirrhosis

Background and Aim

To investigate the short-term dynamic changes and the factors associated with regression of glucose metabolism disorders in patients with hepatitis flare of chronic hepatitis B virus (HBV) infection.

Methods

In this study, 118 patients with severe hepatitis flare of chronic HBV infection were prospectively studied. Oral glucose tolerance test was performed on admission and during follow-up to evaluate dynamic changes in glucose metabolism disorders. The factors associated with regression of glucose metabolism disorders were identified using univariate and multivariate logistic regression analyses.

Results

The prevalence of diabetes was significantly higher in 70 (47.1%) patients with liver cirrhosis than that in 48 (16.8%) patients without liver cirrhosis. The prevalence of impaired glucose tolerance in patients with liver cirrhosis (35.7%) was significantly lower than that in patients without liver cirrhosis (47.8%). After a follow-up of 20.0 ± 18.7 days, 28 of 31 (90.3%) patients without liver cirrhosis experienced regression of glucose metabolism disorders. Additionally, 30 (54.5%) patients with liver cirrhosis experienced regression of glucose metabolism disorders after 42.0 ± 36.2 days. In patients with liver cirrhosis, those with regression of glucose metabolism disorders had significantly higher levels of homeostasis model assessment-β-cell function, albumin (ALB), and a significantly lower level of fibrosis-4 score. ALB was identified as an independent factor associated with the regression of glucose metabolism disorders in patients with liver cirrhosis.

Conclusion

Severe acute liver inflammation aggravates glucose metabolism disorders in patients with hepatitis B-related liver cirrhosis and high ALB level is associated with regression of glucose metabolism disorders upon resolution of acute liver inflammation.

The IGFBP3/TMEM219 pathway regulates beta cell homeostasis

Loss of pancreatic beta cells is a central feature of type 1 (T1D) and type 2 (T2D) diabetes, but a therapeutic strategy to preserve beta cell mass remains to be established. Here we show that the death receptor TMEM219 is expressed on pancreatic beta cells and that signaling through its ligand insulin-like growth factor binding protein 3 (IGFBP3) leads to beta cell loss and dysfunction. Increased peripheral IGFBP3 was observed in established and at-risk T1D/T2D patients and was confirmed in T1D/T2D preclinical models, suggesting that dysfunctional IGFBP3/TMEM219 signaling is associated with abnormalities in beta cells homeostasis. In vitro and in vivo short-term IGFBP3/TMEM219 inhibition and TMEM219 genetic ablation preserved beta cells and prevented/delayed diabetes onset, while long-term IGFBP3/TMEM219 blockade allowed for beta cell expansion. Interestingly, in several patients' cohorts restoration of appropriate IGFBP3 levels was associated with improved beta cell function. The IGFBP3/TMEM219 pathway is thus shown to be a physiological regulator of beta cell homeostasis and is also demonstrated to be disrupted in T1D/T2D. IGFBP3/TMEM219 targeting may therefore serve as a therapeutic option in diabetes.

An Analysis of the Risk Factors for New-Onset Diabetes Mellitus After Liver Transplantation

Objective

To investigate the risk factors related to new-onset diabetes mellitus (NODM) and the significance of IL-6.

Methods

A retrospective analysis was conducted on clinical data from 64 patients who received either a living donor liver transplantation or a donation after circulatory death from September 2013 to October 2020 and attended regular follow-up visits for six or more months. During follow-up, patients were randomized into groups and followed up until the completion of the study or the death of the patient.

Results

The incidence of NODM was 31.25% (n = 20). The median age in the NODM group was 52.15 years (p < 0.01). Age (OR = 1.089; 95% CI: 0.0211-0.1495, p = 0.003) and elevated preoperative IL-6 (OR = 1.122; 95% CI: 0.0619-0.1677, p = 0.029) were found to be independent risk factors for NODM. HBV-induced liver cirrhosis, warm ischemia time (WIT), body mass index (BMI), and high preoperative fasting blood glucose (FBG) were also found to be risk factors for NODM. The recipient had a higher risk of NODM if the donor had a high BMI and poor hepatic function. The concentrations of IL-6, procalcitonin (PCT), FBG, and tacrolimus (TAC) in the first month postoperatively were significantly higher in the NODM group than in the NO-NODM group. The survival rate of the patients was not affected by NODM.

Conclusion

HBV-induced liver cirrhosis, WIT, BMI, and high preoperative FBG levels are risk factors for NODM, and age and preoperative IL-6 levels are independent risk factors. To a certain extent, higher BMI and poor hepatic function had reference significance for the incidence of NODM. Patients with a high concentration of FBG, IL-6, and TAC in the first month postoperatively had an increased risk of suffering from NODM.

Blood pressure, glycemic status and advanced liver fibrosis assessed by transient elastography in the general United States population

OBJECTIVE

Few studies investigated the role of different predictors of advanced liver fibrosis in unselected populations. Here, we estimate the prevalence of steatosis and fibrosis in the general United States population by means of transient elastography and evaluate the impact of blood pressure (BP) and diabetes on disease severity.

METHODS

This is a cross-sectional study of United States adults participating in the 2017-2018 cycle of the National Health and Nutrition Examination Survey. Participants underwent a transient elastography examination, and liver steatosis and fibrosis were estimated through the controlled attenuation parameter (CAP) score and liver stiffness measurement (LSM), respectively.

RESULTS

Four thousand, three hundred and seventy-one participants had reliable transient elastography and BP readings. Steatosis (CAP ≥ 248 dB/m), advanced fibrosis (LSM ≥ 9.6 kPa) and cirrhosis (LSM ≥ 13 kPa) were present in 56.9, 5.5 and 2.9% of participants, respectively. After controlling for potential confounders, risk of steatosis increased proportionally going from participants with optimal (reference) to those with normal [odds ratio (OR) 1.24, 95% confidence interval (CI) 0.83-1.86], high normal (OR 1.41, 95% CI 1.01-1.97) and elevated BP (OR 1.64, 95% CI 1.21-2.21), whereas no significant association was found between BP status and liver fibrosis. Conversely, presence of diabetes increased the risk of both steatosis (OR 2.15, 95% CI 1.49-3.11) and advanced fibrosis (OR 2.25, 95% CI 1.36-3.72).

CONCLUSION

Liver steatosis and fibrosis are highly prevalent in the multiethnic United States adult population, raising concerns for future incidence of cirrhosis and its complications. BP status was associated with a progressively higher risk of steatosis, whereas obesity and diabetes were consistently associated with both steatosis and fibrosis.

Glucose Tolerance Stages in Cystic Fibrosis Are Identified by a Unique Pattern of Defects of Beta-Cell Function

OBJECTIVE

We aimed to assess the order of severity of the defects of 3 direct determinants of glucose regulation-beta-cell function, insulin clearance, and insulin sensitivity-in patients with cystic fibrosis (CF), categorized according their glucose tolerance status, including early elevation of mid-level oral glucose tolerance test (OGTT) glucose values (>140 and <200 mg/dL), referred to as AGT140.

METHODS

A total of 232 CF patients aged 10 to 25 years underwent OGTT. Beta-cell function and insulin clearance were estimated by OGTT mathematical modeling and OGTT-derived biomarkers of insulin secretion and sensitivity were calculated. The association between glucometabolic variables and 5 glucose tolerance stages (normal glucose tolerance [NGT], AGT140, indeterminate glucose tolerance [INDET], impaired glucose tolerance [IGT], cystic fibrosis-related diabetes CFRD]) was assessed with a general linear model.

RESULTS

Beta-cell function and insulin sensitivity progressively worsened across glucose tolerance stages (P < 0.001), with AGT140 patients significantly differing from NGT (all P < 0.01). AGT140 and INDET showed a degree of beta-cell dysfunction similar to IGT and CFRD, respectively (all P < 0.01). Insulin clearance was not significantly associated with glucose tolerance stages (P = 0.162). Each stage of glucose tolerance was uniquely identified by a specific combination of defects of the direct determinants of glucose regulation.

CONCLUSIONS

In CF patients, each of the 5 glucose tolerance stages shows a unique pattern of defects of the direct determinants of glucose regulation, with AGT140 patients significantly differing from NGT and being similar to IGT. These findings suggest that AGT140 should be recognized as a distinct glucose tolerance stage and that reconsideration of the grade of glucometabolic deterioration across glucose tolerance stages in CF is warranted.

Insulin Resistance across the Spectrum of Nonalcoholic Fatty Liver Disease

Insulin resistance (IR) is defined as a lower-than-expected response to insulin action from target tissues, leading to the development of type 2 diabetes through the impairment of both glucose and lipid metabolism. IR is a common condition in subjects with nonalcoholic fatty liver disease (NAFLD) and is considered one of the main factors involved in the pathogenesis of nonalcoholic steatohepatitis (NASH) and in the progression of liver disease. The liver, the adipose tissue and the skeletal muscle are major contributors for the development and worsening of IR. In this review, we discuss the sites and mechanisms of insulin action and the IR-related impairment along the spectrum of NAFLD, from simple steatosis to progressive NASH and cirrhosis.

NAFLD and liver transplantation: Disease burden, current management and future challenges

Non-alcoholic fatty liver disease (NAFLD), specifically its progressive form non-alcoholic steatohepatitis (NASH), represents the fastest growing indication for liver transplantation in Western countries. Diabetes mellitus, morbid obesity and cardiovascular disease are frequently present in patients with NAFLD who are candidates for liver transplantation. These factors require specific evaluation, including a detailed pre-surgical risk stratification, in order to improve outcomes after liver transplantation. Moreover, in the post-transplantation setting, the incidence of cardiovascular events and metabolic complications can be amplified by immunosuppressive therapy, which is a well-known driver of metabolic alterations. Indeed, patients with NASH are more prone to developing early post-transplant complications and, in the long-term, de novo malignancy and cardiovascular events, corresponding to higher mortality rates. Therefore, a tailored multidisciplinary approach is required for these patients, both before and after liver transplantation. Appropriate candidate selection, lifestyle modifications and specific assessment in the pre-transplant setting, as well as pharmacological strategies, adjustment of immunosuppression and a healthy lifestyle in the post-transplant setting, play a key role in correct management.

Post-transplant diabetes mellitus and preexisting liver disease - a bidirectional relationship affecting treatment and management

Liver cirrhosis and diabetes mellitus (DM) are both common conditions with significant socioeconomic burden and impact on morbidity and mortality. A bidirectional relationship exists between DM and liver cirrhosis regarding both etiology and disease-related complications. Type 2 DM (T2DM) is a well-recognized risk factor for chronic liver disease and vice-versa, DM may develop as a complication of cirrhosis, irrespective of its etiology. Liver transplantation (LT) represents an important treatment option for patients with end-stage liver disease due to non-alcoholic fatty liver disease (NAFLD), which represents a hepatic manifestation of metabolic syndrome and a common complication of T2DM. The metabolic risk factors including immunosuppressive drugs, can contribute to persistent or de novo development of DM and NAFLD after LT. T2DM, obesity, cardiovascular morbidities and renal impairment, frequently associated with metabolic syndrome and NAFLD, may have negative impact on short and long-term outcomes following LT. The treatment of DM in the context of chronic liver disease and post-transplant is challenging, but new emerging therapies such as glucagon-like peptide-1 receptor agonists (GLP-1RAs) and sodium–glucose cotransporter 2 inhibitors (SGLT2i) targeting multiple mechanisms in the shared pathophysiology of disorders such as oxidative stress and chronic inflammation are a promising tool in future patient management.

Medical management of metabolic and cardiovascular complications after liver transplantation

Liver transplantation represents the only curative option for patients with end-stage liver disease, fulminant hepatitis and advanced hepatocellular carcinoma. Even though major advances in transplantation in the last decades have achieved excellent survival rates in the early post-transplantation period, long-term survival is hampered by the lack of improvement in survival in the late post transplantation period (over 5 years after transplantation). The main etiologies for late mortality are malignancies and cardiovascular complications. The latter are increasingly prevalent in liver transplant recipients due to the development or worsening of metabolic syndrome and all its components (arterial hypertension, dyslipidemia, obesity, renal injury, etc.). These comorbidities result from a combination of pre-liver transplant features, immunosuppressive agent side-effects, changes in metabolism and hemodynamics after liver transplantation and the adoption of a sedentary lifestyle. In this review we describe the most prevalent metabolic and cardiovascular complications present after liver transplantation, as well as proposing management strategies.