Proton Pump Inhibitors and the Possible Development of Hepatic Encephalopathy in Cirrhotic Patients: True Association or Residual Confounding?

Letter: Risks of proton pump inhibitor treatment in cirrhotic patients

This article is linked to Yoon et al paper. To view this article, visit https://doi.org/10.1111/apt.17909

Investigating potential confounding by indication when considering the association between proton pump inhibitor use, infection, hepatic encephalopathy and mortality in hospitalised decompensated cirrhosis: a post-hoc analysis of the ATTIRE trial

Background

Proton pump inhibitors (PPIs) are commonly prescribed to prevent and treat upper gastrointestinal ulceration and bleeding. Studies have identified increased incidence of spontaneous bacterial peritonitis and hepatic encephalopathy (HE) in cirrhosis patients taking PPIs. However, results are conflicting, and as PPIs are prescribed for variceal bleeding, a major risk factor for infection and HE, it is challenging to discern whether these associations are causal.

Methods

In this post-hoc analysis of the ATTIRE trial, we pooled all patient data to investigate the effects of PPI use on clinical outcomes. ATTIRE was a multicentre, open-label, randomised trial of targeted 20% human albumin solution (HAS) daily infusions versus standard care involving 777 adults with decompensated cirrhosis hospitalised with acute complications and albumin <30 g/L. Study recruitment was between Jan 25, 2016, and June 28, 2019, at 35 hospitals across England, Scotland, and Wales. Key exclusion criteria were advanced hepatocellular carcinoma with life expectancy <8 weeks and patients receiving palliative care. In ATTIRE, patients were grouped by PPI use at trial entry. We studied infection and HE at baseline and incidence of hospital acquired infection, new onset HE, renal dysfunction and mortality. We attempted with propensity score matching to account for differences in disease severity.

Findings

Overall PPI use at baseline was not associated with increased incidence of infection, renal dysfunction or mortality, but was associated with significantly increased incidence of grade III/IV HE during hospital stay (P = 0.011). This was only significant for those taking intravenous PPIs and these patients had >10 times the incidence of variceal bleeding and near double the 28-day mortality compared to non-PPI patients. However, propensity score matching was not possible as there was such a strong selection of patients for PPI use, that we could not find sufficient non-PPI patients to match to. We found no impact of PPI use on plasma markers of bacterial translocation, infection or systemic inflammation.

Interpretations

Our real-world data from a completed randomised trial show that PPIs are widely prescribed in the UK and judicious use appears safe in patients hospitalised with decompensated cirrhosis. However, patients prescribed PPIs had fundamentally different phenotypes to those not prescribed PPIs, a form of confounding by indication, which should be strongly considered when interpreting studies and making recommendations about their use.

Funding

Wellcome Trust and Department of Health and Social Care.

The impact of proton pump inhibitors in liver diseases and the effects on the liver

In this systematic and comprehensive overview, we aimed to evaluate the impact of proton pump inhibitors (PPIs) on chronic liver diseases, especially on cirrhosis. A manual and comprehensive search of the PubMed database was conducted to obtain relevant literatures. PPIs altered the composition and function of the intestinal microflora and might lead to small intestinal bacterial overgrowth and bacterial translocation, which were associated with adverse effects in liver diseases. They might increase the risk of hepatic encephalopathy, spontaneous bacterial peritonitis, infections, and are related to an increased mortality in cirrhosis. PPIs might lead to an increased risk of hepatocellular carcinoma, although the mechanism is unknown, and the results are controversial. PPIs also had an impact on the direct-acting antiviral regimen in patients with chronic hepatitis C. They were associated with an increased risk of liver abscess and increased mortality. Additionally, PPIs might lead to metabolic risk events, such as liver steatosis and weight gain. PPIs are associated with several adverse outcomes in liver diseases. Cautious use of PPIs is recommended and clinicians should be aware of the indications for their use in patients with liver diseases.

The prognosis and incidence of hepatic encephalopathy of patients with liver cirrhosis treated with proton pump inhibitors: A multicenter retrospective study in Japan

Gastrointestinal bleeding, hepatic encephalopathy (HE), and hepatocarcinogenesis are associated with the prognosis of patients with liver cirrhosis (LC). Proton pump inhibitors (PPIs) have been used to prevent bleeding, however the effects of PPIs on overall survival have not yet been elucidated. Therefore, this multicenter retrospective study aimed to assess the effect of PPI on the prognosis and HE occurrence of the patients with liver cirrhosis in Japan.A total of 456 patients diagnosed with LC at the 4 institutes during the study period (2010-2014) were assessed. PPI-treated and non-treated patients were compared using propensity score matching analysis. Primary and secondary endpoints of the study were set as the occurrence of HE and overall survival, respectively.A comparison of all cases showed a significantly poorer hepatic reserve function in the PPI-treated patients. The propensity-score matching analysis was performed and 120 PPI-treated patients were 1:1 matched with non-treated patients. The analysis revealed a higher incidence of HE in the PPI-treated than in the non-treated patients (P = .032; hazard ratio [HR], 2.162; 95% confidence interval [CI], 1.066-4.176), but the prognosis of PPI-treated patients was no worse than that of non-treated patients (P = .676; HR, 1.101; 95% CI, 0.702-1.726).This retrospective study showed that PPI administration for the patients with liver cirrhosis may partly be related to the increased incidence of HE but not worsen the patient prognosis.

Short-Term Proton Pump Inhibitor Use and Hepatic Encephalopathy Risk in Patients with Decompensated Cirrhosis

Objective: A window period of approximately 3–6 months is usually adopted in studies that evaluate hepatic encephalopathy (HE) risk in proton pump inhibitor (PPI) users. However, HE risk after short-term PPI exposure remains unclear. We explored the effect of short-term PPI exposure using a case-crossover study design. Design: Records of patients with decompensated cirrhosis who had received an HE diagnosis were retrieved from the National Health Insurance Research Database. PPI use rates were compared for case and control with window periods of 7, 14, and 28 days. The adjusted self-matched odds ratio (OR) and 95% confidence interval (CI) from a conditional logistic regression model were used to determine the association between PPI use and HE risk. Results: Overall, 13 195 patients were analyzed. The adjusted OR for HE risk after PPI exposure was 3.13 (95% CI = 2.33–4.20) for the 7-day window, 4.77 (95% CI = 3.81–5.98) for the 14-day window, and 5.60 (95% CI = 4.63–6.78) for the 28-day window. All PPI categories, except omeprazole and pantoprazole, were associated with an increased HE risk. Irrespective of other precipitating factors, such as recent gastrointestinal bleeding or infection, PPI significantly increased HE risk. Conclusion: Short-term PPI use is significantly associated with HE in patients with decompensated cirrhosis. Physicians should use PPI in these patients for appropriate indications, and carefully monitor signs of HE even after short-term exposure. Owing to the limitations of retrospective design in the current study, further study is warranted to confirm our findings.

Current and future pharmacological therapies for managing cirrhosis and its complications

Due to the restrictions of liver transplantation, complication-guided pharmacological therapy has become the mainstay of long-term management of cirrhosis. This article aims to provide a complete overview of pharmacotherapy options that may be commenced in the outpatient setting which are available for managing cirrhosis and its complications, together with discussion of current controversies and potential future directions. PubMed/Medline/Cochrane Library were electronically searched up to December 2018 to identify studies evaluating safety, efficacy and therapeutic mechanisms of pharmacological agents in cirrhotic adults and animal models of cirrhosis. Non-selective beta-blockers effectively reduce variceal re-bleeding risk in cirrhotic patients with moderate/large varices, but appear ineffective for primary prevention of variceal development and may compromise renal function and haemodynamic stability in advanced decompensation. Recent observational studies suggest protective, haemodynamically-independent effects of beta-blockers relating to reduced bacterial translocation. The gut-selective antibiotic rifaximin is effective for secondary prophylaxis of hepatic encephalopathy; recent small trials also indicate its potential superiority to norfloxacin for secondary prevention of spontaneous bacterial peritonitis. Diuretics remain the mainstay of uncomplicated ascites treatment, and early trials suggest alpha-adrenergic receptor agonists may improve diuretic response in refractory ascites. Vaptans have not demonstrated clinical effectiveness in treating refractory ascites and may cause detrimental complications. Despite initial hepatotoxicity concerns, safety of statin administration has been demonstrated in compensated cirrhosis. Furthermore, statins are suggested to have protective effects upon fibrosis progression, decompensation and mortality. Evidence as to whether proton pump inhibitors cause gut-liver-brain axis dysfunction is conflicting. Emerging evidence indicates that anticoagulation therapy reduces incidence and increases recanalisation rates of non-malignant portal vein thrombosis, and may impede hepatic fibrogenesis and decompensation. Pharmacotherapy for cirrhosis should be implemented in accordance with up-to-date guidelines and in conjunction with aetiology management, nutritional optimisation and patient education.

Association of proton pump inhibitors with the risk of hepatic encephalopathy during hospitalization for liver cirrhosis

BACKGROUND

Hepatic encephalopathy is associated with altered gut microbiota. Proton pump inhibitors increase the risk of small bowel bacterial overgrowth.

OBJECTIVES

This was a case-control study aimed at exploring the relationship of proton pump inhibitor use with the risk of hepatic encephalopathy during hospitalization in liver cirrhosis.

METHODS

Case and control groups were defined as cirrhotic patients who developed hepatic encephalopathy during hospitalization and those without hepatic encephalopathy at admission or during hospitalization, respectively. Age, gender, and Child-Pugh score were matched between the groups. Odds ratios with 95% confidence intervals were calculated to express the association of proton pump inhibitors with the risk of hepatic encephalopathy. Four subgroup analyses were performed after excluding patients with acute upper gastrointestinal bleeding, infections, and in-hospital death, and after matching model for end-stage liver disease score.

RESULTS

In the overall analysis, 128 patients were included in each group of cases and controls. The proportion of proton pump inhibitor use was significantly higher in the case group than the control group (79.7% vs 43%, p < 0.001). Proton pump inhibitor use (odds ratio = 3.481, 95% confidence interval: 1.651-7.340, p = 0.001) was independently associated with the development of hepatic encephalopathy in the multivariate analysis. In the four subgroup analyses, proton pump inhibitor use remained independently associated with the risk of hepatic encephalopathy.

CONCLUSION

Proton pump inhibitor use might increase the risk of hepatic encephalopathy during hospitalization.

The Association Between Proton Pump Inhibitor Use With Acute Kidney Injury and Chronic Kidney Disease

Proton pump inhibitors (PPIs) are among the most commonly prescribed medicines and are the mainstay of treatment for gastroesophageal reflux disease. Recently, there has been an increase in the use of these medicines for unclear and inappropriate indications. Although generally well tolerated and considered to be safe, several observational studies have linked PPI use with a variety of conditions such as pneumonia, Clostridium difficile infection, fractures, hypomagnesemia, and dementia. The well-established association between PPIs and acute interstitial nephritis has raised questions about whether they may also cause acute kidney injury and chronic kidney disease. Observational studies have evaluated these possible associations. This paper reviews the currently available literature about these associations and considers their possible underlying pathophysiological mechanisms. The level of evidence-linking PPI use with acute kidney injury and chronic kidney disease is weak and does not establish causality. More research is required to explore these possible associations further. The PPIs should be used in the lowest effective dose and inappropriate use should be avoided.

Recent advances in hepatic encephalopathy

Hepatic encephalopathy describes the array of neurological alterations that occur during acute liver failure or chronic liver injury. While key players in the pathogenesis of hepatic encephalopathy, such as increases in brain ammonia, alterations in neurosteroid levels, and neuroinflammation, have been identified, there is still a paucity in our knowledge of the precise pathogenic mechanism. This review gives a brief overview of our understanding of the pathogenesis of hepatic encephalopathy and then summarizes the significant recent advances made in clinical and basic research contributing to our understanding, diagnosis, and possible treatment of hepatic encephalopathy. A literature search using the PubMed database was conducted in May 2017 using "hepatic encephalopathy" as a keyword, and selected manuscripts were limited to those research articles published since May 2014. While the authors acknowledge that many significant advances have been made in the understanding of hepatic encephalopathy prior to May 2014, we have limited the scope of this review to the previous three years only.