Association Between Kidney Dysfunction Types and Mortality Among Hospitalized Patients with Cirrhosis

Incidence and risk factors of acute kidney injury in cirrhosis: a systematic review and meta-analysis of 5,202,232 outpatients, inpatients, and ICU-admitted patients

INTRODUCTION

Acute kidney injury (AKI) is a commonly seen condition in the natural course of cirrhosis. The aim of this study was to evaluate the pooled incidence and risk factors of AKI in different clinical stages and situations in patients with cirrhosis.

METHODS

Search was conducted on 13 December 2023 across MEDLINE (PubMed), Embase, and Cochrane databases. Meta-analysis was performed using a generalized linear mixed model.

RESULTS

In total, 73 studies with 5,202,232 patients were finally enrolled in the meta-analysis. AKI commonly occurs among hospitalized cirrhotics experiencing any decompensation event (29%) as well as among stable outpatients (28%) throughout a 1-year follow-up period. On admission, patients with infection or sepsis/septic shock had the highest AKI rate (47%), followed by those with hepatic encephalopathy (41%). Furthermore, the severity of liver disease proved to be a substantial driver for AKI development, while patients at intensive care unit had the greatest AKI incidence (61%).

CONCLUSIONS

Both hospitalized patients and stable outpatients with cirrhosis exhibited an elevated susceptibility to AKI. Patients at intensive care unit and those with severe liver disease, infection, sepsis/septic shock, hepatic encephalopathy, or acute on chronic liver failure upon admission are at higher risk for AKI.

TRIAL REGISTRATION

PROSPERO, registered 09/12/23, CRD42023487736.

Acute kidney injury in patients with cirrhosis: Acute Disease Quality Initiative (ADQI) and International Club of Ascites (ICA) joint multidisciplinary consensus meeting

Patients with cirrhosis are prone to developing acute kidney injury (AKI), a complication associated with a markedly increased in-hospital morbidity and mortality, along with a risk of progression to chronic kidney disease. Whereas patients with cirrhosis are at increased risk of developing any phenotype of AKI, hepatorenal syndrome (HRS), a specific form of AKI (HRS-AKI) in patients with advanced cirrhosis and ascites, carries an especially high mortality risk. Early recognition of HRS-AKI is crucial since administration of splanchnic vasoconstrictors may reverse the AKI and serve as a bridge to liver transplantation, the only curative option. In 2023, a joint meeting of the International Club of Ascites (ICA) and the Acute Disease Quality Initiative (ADQI) was convened to develop new diagnostic criteria for HRS-AKI, to provide graded recommendations for the work-up, management and post-discharge follow-up of patients with cirrhosis and AKI, and to highlight priorities for further research.

Development and validation of prognostic nomogram for cirrhotic patients with acute kidney injury upon ICU admission

This study aims to develop and validate a prognostic nomogram that accurately predicts the short-term survival rate of cirrhotic patients with acute kidney damage (AKI) upon ICU admission. For this purpose, we examined the admission data of 3060 cirrhosis patients with AKI from 2008 to 2019 in the MIMIC-IV database. All included patients were randomly assigned to derivation and validation cohorts in a 7:3 ratio. The derivation cohort used the least absolute shrinkage and selection operator (LASSO) regression model to identify independent predictors of AKI. A prognostic nomogram was constructed via multivariate logistic regression analysis in the derivation cohort and subsequently verified in the validation cohort. Nomogram's discrimination, calibration, and clinical utility were evaluated using the C-index, calibration plot, and decision curve analysis (DCA). A total of 2138 patients were enrolled in the derivation cohort, with a median follow-up period of 15 days, a median survival time of 41 days, and a death rate of 568 patients (26.6%). The cumulative survival rates at 15 and 30 days were 75.8% and 57.5%, respectively. The results of the multivariate analysis indicated that advanced AKI stage, use of vasoactive drugs, advanced age, lower levels of ALB, lower mean sBp, longer INR, and longer PT were all independent risk factors that significantly influenced the all-cause mortality of cirrhosis patients with AKI (all p < 0.01). The C-indices for the derivation and the validation cohorts were 0.821 (95% CI 0.800-0.842) and 0.831 (95% CI 0.810-0.852), respectively. The model's calibration plot demonstrated high consistency between predicted and actual probabilities. Furthermore, the DCA showed that the nomogram was clinically valuable. Therefore, the developed and internally validated prognostic nomogram exhibited favorable discrimination, calibration, and clinical utility in forecasting the 15-day and 30-day survival rates of cirrhosis patients with AKI upon admission to the ICU.

Addition of Kidney Dysfunction Type to MELD-Na for the Prediction of Survival in Cirrhotic Patients Awaiting Liver Transplantation in Comparison with MELD 3.0 with Albumin

It is well known that renal dysfunction has a devastating effect on the prognosis of liver cirrhosis. In this study, the aim was to assess whether the incorporation of the kidney dysfunction type into the MELD-Na score enhances its predictive capacity for outcomes in patients awaiting liver transplantation (LT), compared to utilizing the MELD 3.0 score with albumin. In total, 2080 patients awaiting the LT were enrolled at two tertiary care institutions in Korea. Discrimination abilities were analyzed by using Harrell's c-index and iAUC values between MELD-Na-kidney dysfunction type (MELD-Na-KT) and MELD 3.0 with albumin. Clinical endpoints encompassed 3-month survival, 3-month transplant-free survival (TFS), overall survival (OS), and total TFS. Out of the total of 2080 individuals, 669 (32.16%) were male. Regarding the types of renal function impairment, 1614 (77.6%) were in the normal group, 112 (5.38%) in the AKD group, 320 (15.35%) in the CKD group, and 34 (1.63%) were in the AKD on CKD group. MELD 3.0 with albumin showed better discrimination (c-index = 0.714) compared to MELD-Na-KT (c-index = 0.708) in predicting 3-month survival. Similar results were observed for OS, 3-month TFS, and total TFS as well. When divided by sex, MELD 3.0 with albumin showed the comparable prediction of 3-month survival to MELD-Na-KT (c-index 0.675 vs. 0.671, p-value 0.221) in males. However, in the female group, MELD 3.0 with albumin demonstrated better results compared to MELD-Na-KT (c-index 0.733 vs. 0.723, p-value 0.001). The integration of kidney dysfunction types into the MELD-Na did not yield superior prognostic results compared to the MELD 3.0 score with albumin. Rather, in the female group, the MELD 3.0 score with albumin was better able to predict survival. These findings suggest that laboratory values pertaining to liver dysfunction or creatinine levels may be more significant than the type of kidney dysfunction when predicting the short-term prognosis of LT candidates.

Incidence and outcomes of acute kidney injury including hepatorenal syndrome in hospitalized patients with cirrhosis in the US

BACKGROUND & AIMS

Acute kidney injury (AKI) in cirrhosis is common and associated with high morbidity, but the incidence rates of different etiologies of AKI are not well described in the US. We compared incidence rates, practice patterns, and outcomes across etiologies of AKI in cirrhosis.

METHODS

We performed a retrospective cohort study of 11 hospital networks, including consecutive adult patients admitted with AKI and cirrhosis in 2019. The etiology of AKI was adjudicated based on pre-specified clinical definitions (prerenal/hypovolemic AKI, hepatorenal syndrome [HRS-AKI], acute tubular necrosis [ATN], other).

RESULTS

A total of 2,063 patients were included (median age 62 [IQR 54-69] years, 38.3% female, median MELD-Na score 26 [19-31]). The most common etiology was prerenal AKI (44.3%), followed by ATN (30.4%) and HRS-AKI (12.1%); 6.0% had other AKI, and 7.2% could not be classified. In our cohort, 8.1% of patients received a liver transplant and 36.5% died by 90 days. The lowest rate of death was observed in patients with prerenal AKI (22.2%; p <0.001), while death rates were higher but not significantly different from each other in those with HRS-AKI and ATN (49.0% vs. 52.7%; p = 0.42). Using prerenal AKI as a reference, the adjusted subdistribution hazard ratio (sHR) for 90-day mortality was higher for HRS-AKI (sHR 2.78; 95% CI 2.18-3.54; p <0.001) and ATN (sHR 2.83; 95% CI 2.36-3.41; p <0.001). In adjusted analysis, higher AKI stage and lack of complete response to treatment were associated with an increased risk of 90-day mortality (p <0.001 for all).

CONCLUSION

AKI is a severe complication of cirrhosis. HRS-AKI is uncommon and is associated with similar outcomes to ATN. The etiology of AKI, AKI stage/severity, and non-response to treatment were associated with mortality. Further optimization of vasoconstrictors for HRS-AKI and supportive therapies for ATN are needed.

IMPACT AND IMPLICATIONS

Acute kidney injury (AKI) in cirrhosis carries high morbidity, and management is determined by the etiology of injury. However, a large and well-adjudicated multicenter database from US centers that uses updated AKI definitions is lacking. Our findings demonstrate that acute tubular necrosis and hepatorenal syndrome have similar outcomes (∼50% mortality at 90 days), though hepatorenal syndrome is uncommon (12% of all AKI cases). These findings represent practice patterns at US transplant/tertiary centers and can be used as a baseline, presenting the situation prior to the adoption of terlipressin in the US.

Healthcare burden and outcomes of hepatorenal syndrome among cirrhosis-related hospitalisations in the US

BACKGROUND

Hepatorenal syndrome (HRS) contributes to significant morbidity and mortality in hospitalised patients with cirrhosis.

AIMS

To examine recent trends, magnitude and outcomes of HRS in the National Inpatient Sample (NIS) database METHODS: Among the NIS database on cirrhosis hospitalisations (2016-2019) due to alcohol (ALD), chronic viral hepatitis (CVH), or NASH and complicated by acute kidney injury (AKI) were analyzed.

RESULTS

Of 113,454 hospitalisations, 18,735 (16.5%) had HRS (mean age 56 years, 36% females, 68% whites, 80% ALD, 7% NASH) with a stable trend over time. Among 1:1 propensity-matched 36,090 hospitalisations, the odds of HRS were 12% higher in NASH versus CVH. Based on weighted national estimates, there were 27,180 (8.3 per 100,000 US population) HRS hospitalisations in 2019, with economic burden of $4.2 billion USD. Mean hospitalisation and total charges (ALD vs. CVH vs. NASH) were 11 versus 10.8 versus 9.2 days and 151,000 versus 157,000 versus 120,000 USD, respectively; p < 0.001. In-hospital mortality was 18.9%, higher in HRS (25.8 vs. 12%, p < 0.001), and decreased by 15% annually. Survivors were more likely to be discharged to short- or long-term care facilities (HRS vs. non-HRS [42 vs. 27%, p < 0.001]); only 28.7% received palliative care.

CONCLUSION

HRS was the cause of AKI in 16.5% of patients hospitalised with cirrhosis and conferred significant healthcare burden with 27,180 HRS hospitalisations in 2019 and requiring an estimated 4.2 billion USD for hospital care. While there has been a decrease in in-hospital mortality over time, it remained high at 23.7% in 2019 in those with HRS.

Acute Kidney Injury in Patients with Liver Disease

AKI is commonly encountered in patients with decompensated cirrhosis, and it is associated with unfavorable outcomes. Among factors specific to cirrhosis, hepatorenal syndrome type 1, also referred to as hepatorenal syndrome-AKI, is the most salient and unique etiology. Patients with cirrhosis are vulnerable to traditional causes of AKI, such as prerenal azotemia, acute tubular injury, and acute interstitial nephritis. In addition, other less common etiologies of AKI specifically related to chronic liver disease should be considered, including abdominal compartment syndrome, cardiorenal processes linked to cirrhotic cardiomyopathy and portopulmonary hypertension, and cholemic nephropathy. Furthermore, certain types of GN can cause AKI in cirrhosis, such as IgA nephropathy or viral hepatitis related. Therefore, a comprehensive diagnostic approach is needed to evaluate patients with cirrhosis presenting with AKI. Management should be tailored to the specific underlying etiology. Albumin-based volume resuscitation is recommended in prerenal AKI. Acute tubular injury and acute interstitial nephritis are managed with supportive care, withdrawal of the offending agent, and, potentially, corticosteroids in acute interstitial nephritis. Short of liver transplantation, vasoconstrictor therapy is the primary treatment for hepatorenal syndrome type 1. Timing of initiation of vasoconstrictors, the rise in mean arterial pressure, and the degree of cholestasis are among the factors that determine vasoconstrictor responsiveness. Large-volume paracentesis and diuretics are indicated to relieve intra-abdominal hypertension and renal vein congestion. Direct-acting antivirals with or without immunosuppression are used to treat hepatitis B/C-associated GN. In summary, AKI in cirrhosis requires careful consideration of multiple potentially pathogenic factors and the implementation of targeted therapeutic interventions.

Improving the Model for End-Stage Liver Disease with sodium by incorporating kidney dysfunction types

BACKGROUND AND AIMS

We investigated the impact of the inclusion of kidney dysfunction type on the discrimination and calibration of the Model for End-Stage Liver Disease with sodium (MELD-Na-KT) score.

APPROACH AND RESULTS

We included all adults listed for ≥90 days without exception points from January 1, 2008, through December 31, 2018. We defined kidney dysfunction types as follows: acute kidney disease (AKD; an increase of ≥0.3 mg/dL or ≥50% in serum creatinine in the last 7 days or fewer than 72 days of hemodialysis), chronic kidney disease (CKD; an estimated glomerular filtration rate <60 ml/min/1.73 m2  for 90 days or ≥72 days of hemodialysis), AKD on CKD (met both definitions), or none (met neither definition). We then developed and validated a multivariable survival model with follow-up beginning at the first assessment after 90 days from waitlist registration and ending at the time of death, waitlist removal, or 90 days from enrollment in this study. The predictor variables were MELD-Na and the derived MELD-Na-KT model. In the derivation cohort, kidney dysfunction type was significantly associated with waitlist mortality after controlling for MELD-Na. There was a significant linear interaction between kidney dysfunction type and MELD-Na score. In the validation cohort, we saw an improvement in the discrimination of the model with an increase in the c-index from 0.76 with MELD-Na to 0.78 with MELD-Na-KT (p = 0.002) and a net reclassification index of 10.8% (95% CI, 1.9%-11.4%). The newly derived MELD-Na-KT model had lower Brier scores (MELD-Na-KT 0.042 vs. MELD-Na 0.053).

CONCLUSIONS

This study demonstrates the feasibility and the potential for objectively defined kidney dysfunction types to enhance the prognostication of waitlist mortality provided by the MELD-Na score.