Assessment of renal function in cirrhosis: Sarcopenia, gender and ethnicity matter

Measured glomerular filtration rate predicts liver related deaths better than estimated glomerular filtration rate in advanced chronic liver disease

BACKGROUND & AIMS

Renal dysfunction is prevalent in advanced chronic liver disease (aCLD) and is associated to liver-related death (LRD). This makes a reliable evaluation of renal function (RF) a crucial aspect. RF can be estimated by formulas or measured by gold standard method. Estimated RF is not reliable in aCLD. However, there is a lack of information on the reliability of formulas in the prediction of LRD.

METHODS

We analysed a cohort of patients with aCLD in whom RF was measured by the plasma clearance of iohexol (mGFR) and estimated (eGFR) by formulas: MDRD, CKD-EPI, Royal Free Hospital (RFHC), GRAIL and Mindikoglu-eGFR. LRD was defined as death from hepatic causes. Multivariable analysis was used to evaluate association of mGFR or eGFR with LRD.

RESULTS

161 patients were evaluated, with median follow-up of 28 months, 58 died from LRD. In overall group mGFR (OR 0.99; p = 0.022) and formulas: CKD-EPI (OR 0.98; p = 0.044), GRAIL (OR 0.98; p = 0.038) was associated with LRD. In patients with normal creatinine levels (≤ 1.1 mg/dL), mGFR (OR 0.99; p = 0.031) was whereas any formula was not associated with LRD.

CONCLUSIONS

eGFR appears as an unreliable method for predicting LRDs in aCLD, especially in those with lower creatinine levels. By contrast, mGFR seems to be a superior predictor.

Advancements in MELD Score and Its Impact on Hepatology

There continues to be an ongoing need for fair and equitable organ allocation. The Model for End-Stage Liver Disease (MELD) score has evolved as a calculated framework to evaluate and allocate patients for liver transplantation objectively. The original MELD score has undergone multiple modifications as it is continuously scrutinized for its accuracy in objectively representing the clinical context of patients with liver disease. Several refinements and iterations of the score have been developed, including the widely accepted MELD-Na score. In addition, the most recent updated iteration, MELD 3.0, has been created. The MELD 3.0 calculator incorporates new variables such as patient sex and serum albumin levels and assigns new weights for serum sodium, bilirubin, international normalized ratio, and creatinine levels. It is anticipated that the use of MELD 3.0 scores will reduce overall waitlist mortality and enhance access for female liver transplant candidates. However, despite the emergence of the MELD score as one of the most objective measures for fair organ allocation, various countries and healthcare systems employ alternative methods for stratification and organ allocation. This review article will highlight the origins of the MELD score, its iterations, the current MELD 3.0, and future directions for managing liver transplantation organ allocation. LAY SUMMARY: Organ donation is crucial for the management of patients unwell with liver disease, but organs must be allocated fairly and equitably. One method used for this is the Model for End-Stage Liver Disease (MELD) score, which helps objectively decide which patient is a candidate for liver transplant. Over time, the MELD score has been refined to better reflect patients' needs. For example, the latest version, MELD 3.0, now considers factors like nutrition and gender. This should ensure that more patients, especially females, are candidates and receive appropriate access to liver transplantation. However, not every country uses the MELD score. Some countries have created their own scoring systems based on local research. This review will explain where the MELD score came from, how it has changed, the current characteristics of the MELD 3.0 score, and what the future might hold for organ allocation in liver transplants.

Association of Cystatin C Level with All-cause Mortality in Patients with Liver Cirrhosis: A Meta-analysis

BACKGROUND AND OBJECTIVE

Blood cystatin C level has been introduced as a promising biomarker to detect early kidney injury in cirrhotic patients. The purpose of this meta-analysis was to investigate the association of blood cystatin C level with allcause mortality in patients with liver cirrhosis.

METHODS

PubMed, ScienceDirect, and Embase databases were searched from the inception to November 15, 2022. Observational studies evaluating the value of blood cystatin C level in predicting all-cause mortality in patients with ACS were selected. The pooled hazard risk (HR) with 95% confidence intervals (CI) was calculated using a random effect model meta-analysis.

RESULTS

Twelve studies with 1983 cirrhotic patients were identified. The pooled adjusted HR of all-cause mortality was 3.59 (95% CI 2.39-5.39) for the high versus low group of cystatin C level. Stratified analysis by study design, characteristics of patients, geographical region, sample size, and length of follow-up further supported the predictive value elevated cystatin C level.

CONCLUSION

Elevated cystatin C level was an independent predictor of poor survival in patients with liver cirrhosis. Detection of blood cystatin C level may provide important prognostic information in cirrhotic patients.

Novel Biomarkers of AKI in Cirrhosis

Acute kidney injury (AKI) is a frequent complication in patients with cirrhosis that is associated with poor outcomes and decreased survival. The definition of AKI in cirrhosis is currently based on changes of serum creatinine levels with respect to baseline values. Differential diagnosis of the causes of AKI is of major relevance, considering that some causes of AKI, such as hepatorenal syndrome, have specific treatment options and different prognosis. Prediction of kidney function recovery and patients' survival is also crucial in this patient population to guide clinical decisions. AKI biomarkers in cirrhosis have emerged as a promising tool for differential diagnosis and prognosis in this situation. There are consistent data showing that some urine biomarkers, particularly neutrophil gelatinase-associated lipocalin, may be useful in daily clinical practice for the differential diagnosis of the cause of AKI in cirrhosis. AKI biomarkers may constitute a useful tool for use in differential diagnosis, prognosis of renal function, and survival in patients with cirrhosis. This review focuses on the current state of knowledge and future perspective of novel biomarkers of AKI in cirrhosis.

A novel score predicts mortality after transjugular intrahepatic portosystemic shunt: MOTS - Modified TIPS Score

BACKGROUND AND AIMS

The high risk for severe shunting-related post-interventional complications demands a stringent selection of candidates for transjugular intrahepatic portosystemic shunt (TIPS). We aimed to develop a simple and reliable tool to accurately predict early post-TIPS mortality.

METHODS

144 cases of TIPS implantation were retrospectively analysed. Using univariate and multivariate Cox regression analysis of factors predicting mortality within 90 days after TIPS, a score integrating urea, international normalized ratio (INR) and bilirubin was developed. The Modified TIPS-Score (MOTS) ranges from 0 to 3 points: INR >1.6, urea >71 mg/dl and bilirubin >2.2 mg/dl account for one point each. Additionally, MOTS was tested in an external validation cohort (n = 187) and its performance was compared to existing models.

RESULTS

Modified TIPS-Score achieved a significant prognostic discrimination reflected by 90-day mortality of 8% in patients with MOTS 0-1 and 60% in patients with MOTS 2-3 (p < .001). Predictive performance (area under the curve) of MOTS was accurate (c = 0.845 [0.73-0.96], p < .001), also in patients with renal insufficiency (c = 0.830 [0.64-1.00], p = .02) and in patients with refractory ascites (c = 0.949 [0.88-1.00], p < .001), which are subgroups with particular room for improvement of post-TIPS mortality prediction. The results were reproducible in the validation cohort.

CONCLUSIONS

Modified TIPS-Score is a novel, practicable tool to predict post-TIPS mortality, that can significantly simplify clinical decision making. Its practical applicability should be further investigated.

Sarcopenia HIBA score predicts sarcopenia and mortality in patients on the liver transplant waiting list

Sarcopenia is a prevalent condition that predicts prognosis in patients awaiting liver transplantation (LT). The gold standard for the diagnosis of sarcopenia is the assessment of the muscular area at L3 with computed tomography (CT) scan (skeletal muscle index [SMI]), but the routine use of CT scan is limited in clinical practice. Thus, we designed a single-center observational study aimed to evaluate the clinical factors associated with the presence of sarcopenia by SMI, and to build a score capable of predicting or excluding the presence of sarcopenia in patients on the LT waiting list (WL). Binary logistic regression analysis was performed to establish the factors independently associated with sarcopenia, and the Sarcopenia Hospital Italiano de Buenos Aires (HIBA) score was built from the resulting model after internal validation analysis by bootstrapping and correction for optimism. The predictive capability of mortality on the WL was evaluated with competing risk regression analysis. A total of 215 patients with cirrhosis on the LT WL were included. The independent factors associated with the presence of sarcopenia were male sex (odds ratio [OR]: 6.09, p < 0.001), body mass index (OR: 0.74, p < 0.001), Child Pugh (OR: 1.44, p < 0.001), and the ratio creatinine/Cystatin C (OR: 0.03, p = 0.007). The Sarcopenia HIBA score constructed with these variables showed an area under the curve of 0.862. During follow-up, 77 (36%) patients underwent LT, 46 (21%) died, and 92 (43%) remained alive. After adjusting for Model for End-Stage Liver Disease-Sodium, Sarcopenia HIBA score was an independent predictor of WL mortality (subhazard ratio: 1.19; 95% confidence interval 1.01-1.40; p = 0.042). Sarcopenia HIBA score is an easy-to-use, objective, and reliable diagnostic and predictive tool that can be useful to improve the prognostic evaluation and allow identifying a group of patients with a higher risk of death while awaiting LT.

Overestimated renal function in patients with liver cirrhosis predicts poor prognosis

AIM

A high prevalence of overestimated renal function in patients with liver cirrhosis (LC) has been reported; nonetheless, its impact on prognosis remains unclear. We aimed to evaluate the impact of overestimated renal function on prognosis in patients with LC.

METHODS

An overestimated renal function was defined as a >20% increase in the creatinine-based estimated glomerular filtration rate (eGFR), compared with cystatin C-based eGFR. LC patients with conserved serum, who were evaluated for muscle atrophy and had proper clinical information were included, and their prognostic factors were analyzed.

RESULTS

A total of 215 consecutive patients with LC were included. The prevalence of overestimated renal function was 29.8% (64/215). Kaplan-Meier survival analysis revealed that patients with overestimated renal function had a poorer prognosis than those without overestimated renal function (hazard ratio [HR]: 2.217 95% confidence interval [CI]: 1.290-3.810; p = 0.001). Subgroup analysis showed that overestimated renal function was a significant prognostic factor, irrespective of sex and the presence of hepatocellular carcinoma (HCC). Multivariate Cox regression analyses revealed that overestimated renal function was a significant and independent factor predictive of poor prognosis in the entire cohort (HR: 2.050; 95% CI: 1.041-4.037; p = 0.038) and in subgroups classified by Child-Pugh class A (HR: 2.131; 95% CI: 1.019-4.458; p = 0.044), Model for End-Stage Liver Disease score ≤9 (HR: 2.303; 95% CI: 1.038-5.109; p = 0.04), and presence of HCC (HR: 2.290; 95% CI: 1.128-4.651; p = 0.022).

CONCLUSION

Overestimated renal function is a significant and independent prognostic factor in patients with LC.

The Mortality Index for Alcohol-Associated Hepatitis: A Novel Prognostic Score

OBJECTIVE

To develop a new scoring system that more accurately predicts 30-day mortality in patients with alcohol-associated hepatitis (AH).

METHODS

A cohort of consecutive adults diagnosed with AH at a single academic center from January 1, 1998, to December 31, 2018, was identified for model derivation. Multivariate logistic regression was used to create a new scoring system to predict 30-day mortality. External validation of this score was performed on a multicenter retrospective cohort.

RESULTS

In the derivation cohort of 266 patients, the 30-day mortality rate was 19.2%. The following variables were found to be significantly associated with mortality on multivariate analysis: age (P=.002), blood urea nitrogen (P=.003), albumin (P=.01), bilirubin (P=.02), and international normalized ratio (P=.001). A model incorporating these variables, entitled the Mortality Index for Alcohol-Associated Hepatitis (MIAAH), achieved a C statistic of 0.86. Comparison of the accuracy of the MIAAH to existing prognostic models, including the Model for End-Stage Liver Disease and Maddrey Discriminant Function, showed that the highest concordance was achieved by the MIAAH and that this difference was significant. In the validation cohort of 249 patients, the MIAAH C statistic decreased to 0.73 and was found to be significantly superior to the Maddrey Discriminant Function but not to the Model for End-Stage Liver Disease.

CONCLUSION

The MIAAH competes with the current prognostication models and is at a minimum as accurate as these existing scores in identifying patients with AH at high risk of short-term mortality. Furthermore, the MIAAH demonstrates advantageous performance characteristics in its ability to increasingly accurately dichotomize patients into those at highest risk of death and those likely to survive.

Plasma Cystatin C Level is a Prognostic Marker of Morbidity and Mortality in Hospitalized Decompensated Cirrhotic Patients

Introduction : Cystatin C (CysC) is biomarker for early detection of acute kidney injury (AKI). However, there is limited evidence in decompensated cirrhotic patients without AKI at admission. This study aimed to assess CysC as a predictor of 90-day mortality. Methods : Decompensated cirrhotic patients without AKI were prospectively enrolled. CysC and creatinine were measured within 24 hours of admission and compared between patients with in-hospital complications (AKI, hepatorenal syndrome (HRS), acute-on-chronic liver failure (ACLF)) vs. those without, and survivors vs. non-survivors. The AUROC and cut-off point of CysC in predicting 90-day mortality were determined. Results : Of 137 decompensated cirrhotic patients, 46 without AKI at admission were included (58.7% male, age 60.8 ± 11.2years, MELD 13.1 ± 5.1, ChildA / B / C 43.5% / 39.1% / 17.4%). The mean CysC level tended to be higher in patients with ACLF (1.52 ± 0.60 vs. 1.11 ± 0.28, p = 0.05), and significantly higher in non-survivors than survivors (1.61 ± 0.53 vs. 1.08 ± 0.28, p = 0.013). The 90-day mortality rate was 21.7%. After adjusting with age and bacterial infection on admission, CysC level  ≥ 1.25 mg / L was significantly associated with 90-day mortality. The CysC cut-off level  ≥ 1.25 mg / L provided 80% sensitivity and 75% specificity for predicting 90-day mortality. Conclusion : Plasma CysC within 24 hours could be used as a predictor for 90-day mortality and development of ACLF in decompensated cirrhotic patients. J. Med. Invest. 68 : 302-308, August, 2021.

Post-Liver Transplant Acute Kidney Injury

Acute kidney injury (AKI) is a common condition following liver transplantation (LT). It negatively impacts patient outcomes by increasing the chances of developing chronic kidney disease and reducing graft and patient survival rates. Multiple definitions of AKI have been proposed and used throughout the years, with the International Club of Ascites definition being the most widely now used for patients with cirrhosis. Multiple factors are associated with the development of post-LT AKI and can be categorized into pre-LT comorbidities, donor and recipient characteristics, operative factors, and post-LT factors. Many of these factors can be optimized in an attempt to minimize the risk of AKI occurring and to improve renal function if AKI is already present. A special consideration during the post-LT phase is needed for immunosuppression as certain immunosuppressive medications can be nephrotoxic. The calcineurin inhibitor tacrolimus (TAC) is the mainstay of immunosuppression but can result in AKI. Several strategies including use of the monoclonoal antibody basilixamab to allow for delayed initiation of tacrolimus therapy and minimization through combination and minimization or elimination of TAC through combination with mycophenolate mofetil or mammalian target of rapamycin inhibitors have been implemented to reverse and avoid AKI in the post-LT setting. Renal replacement therapy may ultimately be required to support patients until recovery of AKI after LT. Overall, by improving renal function in post-LT patients with AKI, outcomes can be improved.

Frequency and Characteristics of Overestimated Renal Function in Japanese Patients with Chronic Liver Disease and Its Relation to Sarcopenia

Renal dysfunction and sarcopenia are important prognostic factors in patients with chronic liver disease (CLD). Muscle atrophy can cause the overestimation of renal function based on serum creatinine. However, the frequency of overestimated renal function in Japanese patients with CLD and its relationship with sarcopenia are unclear. In present study, we evaluated the frequency of overestimated renal function, defined as a >20% higher eGFR using creatinine than using cystatin C, in 307 patients with CLD as well as its relationship with indicators of sarcopenia. In total, 24.8% of patients had overestimated renal function. In a multivariate regression analysis, liver cirrhosis (p = 0.004) and psoas muscle mass index (p = 0.049) were significantly associated with overestimated renal function. Loss of skeletal muscle mass was significantly more frequent in both male and female patients with overestimated renal function than without. In males, the loss of muscle strength and rate of sarcopenia, defined as loss of muscle mass and strength, were significantly higher in patients with than without overestimated renal function. The high frequency of overestimated renal function in Japanese patients suggests that indicators of renal function should be carefully considered; furthermore, monitoring and interventions for both renal function and sarcopenia are needed in patients with CLD.

Changes in the estimated renal function after hepatitis C virus eradication with direct-acting antiviral agents: Impact of changes in skeletal muscle mass

Hepatitis C virus (HCV) infection can cause renal dysfunction, expected to improve upon HCV eradication. However, adverse effects of HCV eradication using direct-acting antiviral agents (DAAs) on renal function have been recently reported. This retrospective study aimed to evaluate renal function with glomerular filtration rate (eGFR) estimated using creatinine (eGFRcre) and cystatin C (eGFRcys). Complete clinical information and preserved serum samples were collected from 207 patients with HCV infection treated with interferon-free DAA at baseline and SVR48 (SVR48). Patients who underwent paired computed tomography (CT) at baseline and ≥12 months after DAA were evaluated for changes in skeletal muscle mass using the psoas muscle mass index (PMI). eGFRcre significantly worsened at SVR48, while eGFRcys was similar at baseline and SVR48. At baseline, eGFRcre was significantly higher than eGFRcys; eGFRcre and eGFRcys were similar at SVR48. Multivariate analysis revealed that the presence of liver cirrhosis and low-albumin level, as well as cirrhosis and age, was significantly associated with the overestimation of renal function by eGFRcre at baseline and SVR48, respectively. In the 57 patients who underwent paired CT at baseline and ≥12 months after DAA, relative values of PMI significantly increased after DAA. After DAA, in patients with increased PMI (65% 37/57), eGFRcre significantly worsened but did not change in patients without increased PMI. eGFRcre significantly worsened after DAAs; however, this might not reflect accurate changes in renal function, partially because of changes in skeletal muscle mass. eGFRcys did not change after DAAs, and it is a potential alternative to eGFRcre.

Monitoring Renal Function and Therapy of Hepatorenal Syndrome Patients with Cirrhosis

Acute kidney injury (AKI) is a frequent complication in patients with cirrhosis. Patients with cirrhosis can develop AKI due to different causes. Hepatorenal syndrome (HRS) is a unique cause of AKI occurring in patients with advanced cirrhosis and is associated with high short-term mortality. The differential diagnosis between different causes of AKI may be challenging. In this regard, new urine biomarkers may be helpful. Liver transplantation is the definitive treatment of patients with HRS-AKI. Vasoconstrictors and albumin represent the first-line pharmacologic treatment of HRS-AKI. This review summarizes current knowledge for the diagnosis and management of HRS in cirrhosis.

Cystatin C and Sarcopenia Predict Acute on Chronic Liver Failure Development and Mortality in Patients on the Liver Transplant Waiting List

BACKGROUND

Cystatin C (CysC) is an early biomarker of renal dysfunction scarcely studied in patients awaiting liver transplantation (LT). Sarcopenia is frequent in cirrhosis and impacts prognosis. We aimed to assess the capability of these factors to predict survival and acute-on-chronic liver failure (ACLF) in patients awaiting LT, as well as early post-LT outcomes.

METHODS

Single-center study that included all cirrhotic patients listed for LT between 2014 and 2017. Competing risk regression analysis was used to evaluate the capability of liver-, kidney-, and global status-related variables at waitlist (WL) inclusion to predict WL mortality and ACLF. Variables associated with post-LT outcomes were evaluated with logistic regression analysis.

RESULTS

One-hundred-and-eighty patients were included. Fifty-six (31%) patients developed ACLF, 54 (30%) underwent LT and 35 (19%) died. In the adjusted competing risk regression analysis, CysC ≥ 1.5 mg/L, sarcopenia and MELD-Na were independent predictors of ACLF in the WL, while CysC ≥ 1.5 mg/L, sarcopenia and albumin were independent predictors of mortality. The cumulative incidence of ACLF and mortality at 12 months were 50% and 34% in patients with sarcopenia and CysC ≥1.5 mg/L. An estimated glomerular filtration rate by chronic kidney disease (CKD)-EPI-CysC-creatinine <60 mL/min/1.73 m at WL inclusion was an independent predictor of the need for renal replacement therapy (RRT) in the first month post-LT.

CONCLUSIONS

Higher levels of CysC and sarcopenia are strongly associated with the ACLF and mortality in WL. The assessment of both risk factors may improve the prognostic evaluation and allow identifying a group of patients with a very high risk of poor outcomes while awaiting LT.

Sex specificity of kidney markers to assess prognosis in cirrhotic patients with TIPS

BACKGROUND & AIMS

Renal function assessed by creatinine is a key prognostic factor in cirrhotic patients. However, creatinine is influenced by several factors, rendering interpretation difficult in some situations. This is especially important in early stages of renal dysfunction where renal impairment might not be accompanied by an increase in creatinine. Other parameters, such as cystatin C (CysC) and beta-trace protein (BTP), have been evaluated to fill this gap. However, none of these studies have considered the role of the patient's sex. The present study analysed CysC and BTP to evaluate their prognostic value and differentiate them according to sex.

PATIENTS AND METHODS

CysC and BTP were measured in 173 transjugular intrahepatic portosystemic shunt (TIPS)-patients from the NEPTUN-STUDY(NCT03628807) and analysed their relationship with mortality and sex. Propensity score for age, MELD, etiology and TIPS indication was used.

RESULTS

Cystatin C and BTP showed excellent correlations with creatinine values at baseline and follow-up. CysC was an independent predictor of overall mortality (HR = 1.66(1.33-2.06)) with an AUC of 0.75 and identified a cut-off of 1.55 mg/L in the whole cohort. Interestingly, CysC was significantly lower in females, also after propensity score matching. In males, the only independent predictor was the creatinine level (HR = 1.54(1.25-1.58)), while in females CysC levels independently predicted mortality (HR = 3.17(1.34-7.52)).

CONCLUSION

This study demonstrates for the first time that in TIPS-patients creatinine predicts mortality in males better than in females, whereas CysC is a better predictor of mortality in females. These results may influence future clinical decisions on therapeutic options for example, allocation for liver transplantation in TIPS-patients.