A risk score to predict the development of hepatic encephalopathy in a population-based cohort of patients with cirrhosis

The Use of Administrative Data to Investigate the Population Burden of Hepatic Encephalopathy

Hepatic encephalopathy (HE) is a devastating complication of cirrhosis with an increasing footprint in global public health. Although the condition is defined using a careful history and examination, we cannot accurately measure the true impact of HE relying on data collected exclusively from clinical studies. For this reason, administrative data sources are necessary to study the population burden of HE. Administrative data is generated with each health care encounter to account for health care resource utilization and is extracted into a dataset for the secondary purpose of research. In order to utilize such data for valid analysis, several pitfalls must be avoided—specifically, selecting the particular database capable of meeting the needs of the study’s aims, paying careful attention to the limits of each given database, and ensuring validity of case definition for HE specific to the dataset. In this review, we summarize the types of data available for and the results of administrative data studies of HE.

Contemporary Epidemiology of Chronic Liver Disease and Cirrhosis

BACKGROUND & AIMS

Accurate estimates for the contemporary burden of chronic liver disease (CLD) are vital for setting clinical, research, and policy priorities. We aimed to review the incidence, prevalence, and mortality of CLD and its resulting complications, including cirrhosis and hepatocellular carcinoma (HCC).

METHODS

We reviewed the published literature on the incidence, prevalence, trends of various etiologies of CLD and its resulting complications. In addition, we provided updated data from the Centers for Disease Control and Global Burden of Disease Study on the morbidity and mortality of CLD, cirrhosis, and hepatocellular carcinoma (HCC). Lastly, we assessed the strengths and weaknesses of available sources of data in hopes of providing important context to these national estimates of cirrhosis burden.

RESULTS

An estimated 1.5 billion persons have CLD worldwide and the age-standardized incidence of CLD and cirrhosis is 20.7/100,000, a 13% increase since 2000. Similarly, cirrhosis prevalence and mortality has increased in recent years in the United States. The epidemiology of CLD is shifting, reflecting implementation of large-scale hepatitis B vaccination and hepatitis C treatment programs, the increasing prevalence of the metabolic syndrome, and increasing alcohol misuse.

CONCLUSIONS

The global burden of CLD and cirrhosis is substantial. Although vaccination, screening, and antiviral treatment campaigns for hepatitis B and C have reduced the CLD burden in some parts of the world, concomitant increases in injection drug use, alcohol misuse, and metabolic syndrome threaten these trends. Ongoing efforts to address CLD-related morbidity and mortality require accurate contemporary estimates of epidemiology and outcomes.

Fibrosis index predicts variceal bleeding and reduces need for nonselective beta-blocker in compensated cirrhosis with initial small esophageal varices without red-color sign

BACKGROUND

Various non-invasive markers predicting hepatic fibrosis are poor predictors of esophageal variceal bleeding (EVB). Elastography performs well but resource-limited. Controversy for small EV prevention also exists. We aim to investigate if a non-invasive marker could predict subsequent EVB within 1 and 2 years in patients with compensated liver cirrhosis (CLC), initial small EV without red-color sign (RCS), without use of non-selective beta-blockers (NSBB) and endoscopic variceal ligation (EVL). This marker would also be tested if it could help reduce use of NSBB, thereby avoiding potential side effects and saving medical costs.

METHODS

In this retrospective cohort study, 6,803 CLC patients fulfilling the inclusion-exclusion criteria were enrolled between 2001 and 2018, and were followed-up for 1 year, 2 years. The primary outcomes were subsequent EVB within 1 and 2 years of enrollment. Another 281 CLC patients with NSBB use were compared for additional outcome analysis.

RESULTS

In total, 539 patients and 710 patients experienced EVB within 1 year and 2 years, respectively. The fibrosis index (FI) with cut-off value of 3.95 showed a negative predictive value (NPV) of 94.3% and an area under receiver operating characteristic (AUROC) of 62.95% for predicting subsequent EVB within 1 year. The EVB and mortality of patients with FI <3.95 and not taking NSBB were significantly lower than those of the other 3 groups. Similar results were demonstrated within 2 years.

CONCLUSIONS

In CLC patients with initial small EV and no RCS, low FI scores showed a high NPV and moderate AUROC in predicting subsequent EVB and mortalities, signifying clinically non-significant portal hypertension. Patients with low FI scores and not taking NSBB had significantly lowest EVB and mortality. The medical cost savings for cutting NSBB in these patients would be estimated at least $3 million per year in the U.S. Further randomized control trial study needed to validate this screening tool.

Important Unresolved Questions in the Management of Hepatic Encephalopathy: An ISHEN Consensus

Management of hepatic encephalopathy (HE) remains challenging from a medical and psychosocial perspective. Members of the International Society for Hepatic Encephalopathy and Nitrogen Metabolism recognized 5 key unresolved questions in HE management focused on (i) driving, (ii) ammonia levels in clinical practice, (iii) testing strategies for covert or minimal HE, (iv) therapeutic options, and (v) nutrition and patient-reported outcomes. The consensus document addresses these topical issues with a succinct review of the literature and statements that critically evaluate the current science and practice, laying the groundwork for future investigations.

Outcomes after hepatic encephalopathy in population-based cohorts of patients with cirrhosis

BACKGROUND

Hepatic encephalopathy is a devastating complication of cirrhosis.

AIM

To describe the outcomes after developing hepatic encephalopathy among contemporary, aging patients.

METHODS

We examined data for a 20% random sample of United States Medicare enrolees with cirrhosis and Part D prescription coverage from 2008 to 2014. Among 49 164 persons with hepatic encephalopathy, we evaluated the associations with transplant-free survival using Cox proportional hazard models with time-varying covariates (hazard ratios, HR) and incidence rate ratios (IRR) for healthcare utilisation measured in hospital-days and 30-day readmissions per person-year. We validated our findings in an external cohort of 2184 privately insured patients with complete laboratory values.

RESULTS

Hepatic encephalopathy was associated with median survivals of 0.95 and 2.5 years for those ≥65 or <65 years old and 1.1 versus 3.9 years for those with and without ascites. Non-alcoholic fatty-liver disease posed the highest adjusted risk of death among aetiologies, HR 1.07 95% CI (1.02, 1.12). Both gastroenterology consultation and rifaximin utilisation were associated with lower mortality, respective adjusted-HR 0.73 95% CI (0.67, 0.80) and 0.40 95% CI (0.39, 0.42). Thirty-day readmissions were fewer for patients seen by gastroenterologists (0.71 95% CI [0.57-0.88]) and taking rifaximin (0.18 95% CI [0.08-0.40]). Lactulose alone was associated with fewer hospital-days, IRR 0.31 95% CI (0.30-0.32), than rifaximin alone, 0.49 95% CI (0.45-0.53), but the optimal therapy combination was lactulose/rifaximin, IRR 0.28 95% CI (0.27-0.30). These findings were validated in the privately insured cohort adjusting for model for endstage liver disease-sodium score and serum albumin.

CONCLUSIONS

Hepatic encephalopathy remains morbid and associated with poor outcomes among contemporary patients. Gastroenterology consultation and combination lactulose-rifaximin are both associated with improved outcomes. These data inform the development of care coordination efforts for subjects with cirrhosis.

Reduced Incidence of Hepatic Encephalopathy and Higher Odds of Resolution Associated With Eradication of HCV Infection

BACKGROUND & AIMS

It is unclear whether a sustained virologic response (SVR) to direct-acting antiviral (DAA) therapy reduces the risk of incident hepatic encephalopathy (HE) in patients with hepatitis C virus (HCV) infection or whether it leads to resolution of pre-existent HE.

METHODS

We identified 71,457 patients who initiated antiviral treatments in the Veterans Affairs Healthcare System from January 1, 1999 through December 31, 2015; 35,871 patients (58%) received only interferon, 4535 patients (7.2%) received DAAs plus interferon, and 21,948 patients (35%) received DAA-only regimens. We collected data from patients through October 31, 2018, for an average of 6.6 years. We evaluated the association between SVR and the development of incident HE or the resolution of pre-existent HE (defined by cessation of pharmacotherapy) as well as the risk of hospitalization with HE after adjusting for potential confounders.

RESULTS

Compared to no SVR, SVR after DAA therapy was associated with a significantly lower risk of developing HE (0.28 vs 1.39 per 100 person-years; adjusted hazard ratio [AHR] 0.41; 95% CI, 0.32-0.51). This association persisted among patients with co-morbid alcohol use disorder and diabetes as well as patients with cirrhosis (AHR, 0.36; 95% CI, 0.31-0.43) and model for end-stage liver disease (MELD) scores of 9 or more (AHR, 0.36; 95% CI, 0.30-0.44). SVR was also associated with reduced risk of hospitalization with HE (AHR, 0.59; 95% CI, 0.43-0.81). Among 2396 patients who were receiving pharmacotherapy for HE at the time of antiviral treatment, SVR was associated with a significantly increased likelihood of HE resolution for those with MELD scores below 9 (AHR, 2.26; 95% CI, 1.74-2.93) but not those with MELD scores of 9 or more.

CONCLUSIONS

In a retrospective study of veterans, we found DAA eradication of HCV infection to be associated with a 59% reduction in risk of development of HE and a > 2-fold increased likelihood of resolution of pre-existing HE in all subgroups except patients with MELD scores of 9 or more.

Epidemiology of Hepatic Encephalopathy

Hepatic encephalopathy (HE) is a complex condition with multiple causes each with varying degrees of severity. HE negatively impacts patients' quality of life, and it is associated with significant burdens to patients and their caregivers. The prevalence of cirrhosis, the most common risk factor for HE, has steadily increased during recent years. In turn, an upsurge in the clinical and health care burdens related to HE is expected in the upcoming years. This article provides a comprehensive review of the epidemiology of HE.

Oral glutamine challenge is a marker of altered ammonia metabolism and predicts the risk of hepatic encephalopathy

BACKGROUND

The current therapies for hepatic encephalopathy (HE) are not completely effective in all patients, probably due to the physiopathological heterogeneity and the different conditions underlying the bout of HE. We hypothesized that oral glutamine challenge (OGC) is able to predict the risk of HE through the identification of various features and types of HE.

METHODS

We included 238 cirrhotic patients (198 without and 40 with a previous HE episode) that underwent OGC, obtaining baseline and 60 minutes post-load ammonia levels. Combined evaluation of baseline hyperammonemia (>78 mcg/dL) and impaired OGC (Δ >32 mcg/dL) defined low-, intermediate- and high-risk groups. Patients were censored at HE, liver transplantation and death or 6 years of follow-up.

RESULTS

The 28.3% (56/198) of the main cohort suffered from HE during the follow-up. In the competing risk analysis, both intermediate- (subhazard ratio (sHR) 2.01 (95% CI 1.00-4.14); P = .048) and high-risk groups (sHR 4.67 (95% CI 2.19-9.98); P = .0001) were associated with the first HE episode, together with age and albumin. Similar results were found for repeated HE events. The cumulative incidence for HE of the high-risk group was two and four times greater than the intermediate- and low-risk groups, respectively. The HE grade was also higher in individuals with the greatest risk (P = .035). The most common precipitant factor was diuretics in the high-risk group, while infections and electrolyte imbalance predominated in the rest of patients.

CONCLUSION

Oral glutamine challenge identified patients at risk of HE and defined specific features of the episodes. This tool could be useful in the decision-making process for the adequate management of HE.

Opioid prescriptions are associated with hepatic encephalopathy in a national cohort of patients with compensated cirrhosis

BACKGROUND

Opioids are often prescribed for pain in cirrhosis and may increase the risk of hepatic encephalopathy (HE).

AIM

To assess the association between opioids and HE in patients with well-compensated cirrhosis.

METHODS

We used the IQVIA PharMetrics (Durham, NC) database to identify patients aged 18-64 years with cirrhosis. We excluded patients with any decompensation event from 1 year before cirrhosis diagnosis to 6 months after cirrhosis diagnosis. Over the 6 months after cirrhosis diagnosis, we determined the duration of continuous opioid use and classified use into short term (1-89 days) and chronic (90-180 days). We assessed whether patients developed HE over the subsequent year (ie 6-18 months after cirrhosis diagnosis). We used a landmark analysis and performed multivariable Cox proportional hazards regression to assess associations between opioid use and HE, adjusting for relevant confounders.

RESULTS

The cohort included 6451 patients with compensated cirrhosis, of whom 23.3% and 4.7% had short-term and chronic opioid prescriptions respectively. Over the subsequent year, HE occurred in 6.3% patients with chronic opioid prescriptions, 5.0% with short-term opioid prescriptions and 3.3% with no opioid prescriptions. In the multivariable model, an increased risk of HE was observed with short-term (adjusted hazard ratio, HR 1.44, 95% CI 1.07-1.94) and chronic opioid prescriptions (adjusted HR 1.83, 95% CI 1.07-3.12) compared to no opioid prescriptions.

CONCLUSION

In this national cohort of privately insured patients with cirrhosis, opioid prescriptions were associated with the risk of incident HE. Opioid use should be minimised in those with cirrhosis and, when required, limited to short duration.

Incidence of and Risk Factors for Hepatic Encephalopathy in a Population-Based Cohort of Americans With Cirrhosis

Hepatic encephalopathy (HE) is a devastating complication of cirrhosis. Data are limited regarding the incidence of and risk factors for HE among contemporary patients in the context of the shifting epidemiology of cirrhosis. We examined a 20% random sample of U.S. Medicare enrollees with cirrhosis and Part D prescription coverage from 2008 to 2014. We modelled incident HE using demographic, clinical, and pharmacologic data. Risk factors for HE were evaluated, including demographics/socioeconomics, cirrhosis etiology, severity of liver disease, and pharmacotherapy, along with gastroenterology consultation, as time-varying covariates. Among 166,192 Medicare enrollees with cirrhosis followed for 5.25 (interquartile range [IQR], 2.00-7.00) years, the overall incidence of HE was 11.6 per 100 patient-years. The cohort's median age was 65 years (IQR, 57-72), 31% had alcohol-related cirrhosis, and 49% had likely nonalcoholic fatty liver disease cirrhosis. The two strongest associations with HE were alcohol-related cirrhosis (adjusted hazard ratio [AHR], 1.44; 95% confidence interval [CI], 1.40, 1.47, relative to nonalcoholic nonviral cirrhosis) and the presence of portal hypertension (AHR, 3.42; 95% CI, 3.34, 3.50). Adjusting for confounders, benzodiazepines (AHR, 1.24; 95% CI, 1.21, 1.27), gamma aminobutyric acid (GABA)ergics (AHR, 1.17; 95% CI, 1.14, 1.21), opioids (AHR, 1.24; 95% CI, 1.21, 1.27), and proton pump inhibitors (PPIs) (AHR, 1.41; 95% CI, 1.38, 1.45) were all associated with incident HE. Only benzodiazepines, however, were associated with the risk of hospitalization with HE (incidence-rate ratio, 1.23; 95% CI, 1.20, 1.26). Conclusion: Novel data regarding the risk of HE for contemporary patients with cirrhosis are provided. The incidence of HE in an older population of Americans with cirrhosis is high, particularly among those with alcohol-related cirrhosis and portal hypertension. Several medication classes, namely PPIs, opiates, GABAergics, and benzodiazepines, represent potentially modifiable risk factors for HE.

Raised serum Interleukin-6 identifies patients with liver cirrhosis at high risk for overt hepatic encephalopathy

BACKGROUND

Systemic inflammation is a driving force for the development of hepatic encephalopathy and recent studies demonstrated that elevated Interleukin-6 (IL-6) serum levels are associated with the presence of minimal hepatic encephalopathy in patients with liver cirrhosis.

AIM

To test the hypothesis that IL-6 is a suitable marker to identify patients with liver cirrhosis at high risk for the development of overt hepatic encephalopathy.

METHODS

201 patients were included into this prospective cohort study and were followed for a mean time of 322 days. Covert hepatic encephalopathy was diagnosed according to the West-Haven criteria (hepatic encephalopathy grade 1) and with the portosystemic encephalopathy (PSE) test.

RESULTS

The cumulative incidence of overt hepatic encephalopathy was higher in patients with IL-6 levels above the median of 9 pg/mL than in patients with IL-6 levels at or below the median (35.6% vs 1.9%, P < .001). After adjustment for covert hepatic encephalopathy, history of overt hepatic encephalopathy, C-reactive protein (CRP) and model for end-stage liver disease (MELD), IL-6 levels above the median remained independently associated with the development of overt hepatic encephalopathy. The predictive performance of IL-6 regarding the development of overt hepatic encephalopathy during the next 180 days (AUROC, 0.931) was numerically higher than that of MELD (AUROC, 0.841) or CRP (AUROC, 0.835). In patients without prior overt hepatic encephalopathy, the predictive performance of IL-6 (AUROC, 0.966) was even significantly higher than that of MELD (AUROC 0.843) or CRP (AUROC 0.850). The ideal cut-off for IL-6 in this setting was 23.5 pg/mL with a sensitivity and specificity of 89.3% and 89.5% respectively.

CONCLUSION

IL-6 serum levels are closely linked to the development of overt hepatic encephalopathy in patients with liver cirrhosis.

Association of serum albumin level with incidence and mortality of overt hepatic encephalopathy in cirrhosis during hospitalization

BACKGROUND

Hepatic encephalopathy (HE) is a serious complication of cirrhosis. Decreased serum albumin (ALB) level may facilitate the development of HE and accelerate the death of cirrhotic patients with HE. Recent evidence also suggests that human albumin infusion may reduce the incidence of HE and improve the outcomes of cirrhotic patients. This study aimed to explore the association of serum ALB level with the development of overt HE and HE-associated mortality during hospitalization.

METHODS

Cirrhotic patients admitted to our hospital between January 2010 and February 2019 were screened. Independent predictors for HE were identified by logistic regression analyses. Odds ratio (OR) with 95% confidence interval (95% CI) was calculated. Area under curve (AUC) was calculated by receiver operator characteristic curve analyses.

RESULTS

Of the 2376 included patients with cirrhosis but without HE at admission, 113 (4.8%) developed overt HE during hospitalizations. ALB level (OR = 0.878, 95% CI = 0.834-0.924) was an independent risk factor for development of overt HE. AUC of ALB level for predicting the development of overt HE was 0.770 (95% CI = 0.752-0.787, p < 0.0001), and the best cut-off value was ⩽31.6 g/l. Of the 183 included patients with cirrhosis and overt HE at admission, 20 (10.9%) died during hospitalizations. ALB level (OR = 0.864, 95% CI = 0.771-0.967) was an independent risk factor for death from overt HE. The AUC of ALB level for predicting death from overt HE was 0.737 (95% CI = 0.667-0.799, p = 0.0001), and the best cut-off value was ⩽22.8 g/l.

CONCLUSIONS

Decreased serum ALB level may be associated with higher risk of overt HE and HE-associated mortality during hospitalizations in cirrhosis.

Predicting Overt Hepatic Encephalopathy for the Population With Cirrhosis

Hepatic encephalopathy (HE) is associated with poor quality of life, sharply increased mortality, repeated hospitalizations, falls, and motor vehicle accidents. HE manifests with a dynamic spectrum of severity. Overt HE is clinically obvious disorientation, even coma. Although multiple strategies are available to characterize early-stage HE, data are limited that validate these methods in predicting overt HE, many are impractical in clinical practice, and test cutoffs relevant to the average patient clinicians manage are lacking. To accurately and efficiently classify the risk of overt HE in the population with cirrhosis, novel strategies may be needed. Herein, we review the potential competing strategies for the prediction of overt HE. Conclusion: We propose refining diagnostic cutoffs for tests that are designed to define early HE, using overt HE as a gold standard and expanding prediction tools by using measures of components from the risk pathway for HE.

Contemporary Epidemiology of Cirrhosis

PURPOSE OF REVIEW

We sought to review the contemporary epidemiology of cirrhosis, focusing on the relative burden of the most common chronic liver diseases.

RECENT FINDINGS

The key findings in the review highlight the increasing prevalence and impact of alcohol-related liver disease, particularly among young people, and the epidemic of nonalcoholic fatty liver commensurate with rising rates of obesity. We also contrast recent advances in the care of persons with hepatitis C with the lamentable rise in new infections associated with intravenous drug use. Finally, we highlight the impact of both conventional complications of cirrhosis (namely hepatic encephalopathy) but also the host of patient-reported outcomes adversely impacted by the symptoms of cirrhosis. Cirrhosis is associated with an expanding footprint in contemporary public health. In order to improve global outcomes, we must not only focus on the identifying and treating persons with viral hepatitis but also preventing the rise of alcohol-related liver disease and nonalcoholic fatty liver disease while attending to the urgent patient-centered needs posed by the symptoms of cirrhosis.