Use of histamine H2 receptor antagonists and outcomes in patients with heart failure: a nationwide population-based cohort study

A Real-World Disproportionality Analysis of Histamine H2-Receptors Antagonists (Famotidine): A Pharmacovigilance Study Based on Spontaneous Reports in the FDA Adverse Event Reporting System

Famotidine is an H2 receptor antagonist and is currently used on a large scale in gastroenterology. However, Famotidine may also cause severe toxicity to organ systems, including the blood system, digestive system, and urinary system. The objective of this study was to scientifically and systematically investigate the adverse events (AEs) of Famotidine in the real world through the FDA Adverse Event Reporting System (FAERS) database. A disproportionality analysis was used to quantify the signals of AEs associated with Famotidine in FAERS data from the first quarter of 2004 to the first quarter of 2023. The clinical features, onset time, oral and intravenous administration and severe consequences of Famotidine induced AEs were further analyzed. Among the four tests, we found several AEs that were not mentioned in the drug label. For example, abdominal pain upper, abdominal discomfort, dyspepsia, liver disorder, gastrooesophageal reflux disease, and rhabdomyolysis. These AEs are consistent with the drug instructions. Interestingly, we found several unreported AEs, such as: cerebral infarction, hypocalcaemia, hallucination, visual, hypomagnesaemia, hypoparathyroidism, diabetes insipidus, vulvovaginal candidiasis, retro-orbital neoplasm, neuroblastoma recurrent, and malignant cranial nerve neoplasm. Most of our findings are consistent with clinical observations and drug labels, and we also found possible new and unexpected AEs signals, which suggest the need for prospective clinical studies to confirm these results and explain their relationships. Our findings provide valuable evidence for further safety studies.

Gastroprotection in Heart Failure and Outcomes: A Systematic Review of Proton Pump Inhibitors and Histamine-2 Receptor Antagonists

PURPOSE

The management of heart failure (HF) frequently includes gastroprotection via proton pump inhibitors (PPIs) or histamine-2 receptor antagonists (H2RAs). This systematic review evaluates their impact on HF outcomes, including exacerbation, hospitalization, mortality, and major adverse cardiac events (MACE).

METHODS

In accordance with PRISMA guidelines, a complete search across databases such as PubMed/Medline, Scopus, and Web of Science was conducted until December 10, 2023. The inclusion criteria covered research on adult patients with HF that focused on the effects of PPI and H2RA usage. The risk of bias was determined via the Newcastle-Ottawa Scale (NOS), and data were synthesized quantitatively.

RESULTS

Eleven studies encompassing 996,498 participants were analyzed. The data is not consistent across all research; however, some have suggested that PPI use may be linked to an increased risk of cardiovascular illnesses and heart failure aggravation. Conversely, H2RAs appeared to offer potential benefits in certain high-risk groups, potentially reducing all-cause and cardiovascular mortality. However, the limitations of the available studies should be taken into consideration when interpreting these findings.

CONCLUSION

The review suggests that there may be differences in the impact of PPIs and H2RAs on HF outcomes. While some evidence indicates that PPIs may be linked to increased risks in HF patients, and H2RAs may offer potential benefits, these findings are not definitive and should be interpreted with caution. Further research is necessary to clarify these associations and guide clinical practice.

REGISTRATION

PROSPERO CRD42023491752.

H2 antihistamines: May be useful for combination therapies in cancer?

Cancer morbimortality is still a great concern despite advances in research and therapies. Histamine and its receptors' ligands can modulate different biological responses according to the cell type and the receptor subtype involved. Besides the wide variety of histamine functions in normal tissues, diverse roles in the acquisition of hallmarks of cancer such as sustained proliferative signaling, resistance to cell death, angiogenesis, metastasis, altered immunity and modified microenvironment have been described. This review summarizes the present knowledge of the various roles of histamine H2 receptor (H2R) ligands in neoplasias. A bioinformatic analysis of human tumors showed dissimilar results in the expression of the H2R gene according to tumor type when comparing malignant versus normal tissues. As well, the relationship between patients' survival parameters and H2R gene expression levels also varied, signaling important divergences in the role of H2R in neoplastic progression in different cancer types. Revised experimental evidence showed multiple effects of H2R antihistamines on several of the cited hallmarks of cancer. Interventional and retrospective clinical studies evaluated different H2R antihistamines in cancer patients with two main adjuvant uses: improving antitumor efficacy (which includes regulation of immune response) and preventing toxic adverse effects produced by chemo or radiotherapy. While there is a long path to go, research on H2R antihistamines may provide new opportunities for developing more refined combination therapeutic strategies for certain cancer types to improve patients' survival and health-related quality of life.

Proton pump inhibitors associated with an increased risk of mortality in elderly: a systematic review and meta-analysis

PURPOSE

The increased use of proton pump inhibitors (PPIs) in the elderly has raised concerns about potential severe adverse effects. Our systematic review investigated the mortality associated with PPI use in elderly populations.

METHODS

We searched MEDLINE, EMBASE, and the Cochrane Library for relevant publications until August 2022. We included randomized controlled trials (RCTs), quasi-RCTs, and observational studies on the association between proton pump inhibitors and mortality in the elderly. To estimate the pooled relative risk (RR) and 95% confidence interval (CI), the inverse-variance random effect model was used. Heterogeneity was assessed using the I2 test. Subgroup analyses were performed by follow-up period, population, and study design.

RESULTS

A total of 4 RCTs and 36 cohort studies were included in the meta-analysis. Four RCTs showed that there was no significant association between PPIs and the risk of death. From 23 observational studies (26 cohorts), the use of proton pump inhibitors was not significantly associated with increased mortality in the elderly (RR 1.14; 95% CI, 0.90-1.45). However, when controlling for covariates from 33 observational studies (41 cohorts), proton pump inhibitors in older adults aged 50 years or more were significantly associated with a 15% higher risk of mortality compared to nonusers (RR 1.15; 95% CI, 1.10-1.20).

CONCLUSIONS

Our meta-analysis of RCTs found that PPIs did not show a significant association with increased mortality risk in older adults. However, the meta-analysis of cohort studies and long-term follow-up studies showed a higher increased risk of death with PPI use in older adults. The prescription of PPIs in patients aged 50 years or older should be carefully considered.

The benefit of omeprazole exposure on all-cause mortality and length of ICU/hospital stay might vary with age in critically ill pediatric patients: A cohort study

PURPOSE

To investigate the association between proton pump inhibitors (PPIs) administration during hospitalization and mortality and length of stay in critically ill pediatric patients.

MATERIALS AND METHODS

This is a retrospective observational cohort study on pediatric ICU patients (0 to 18 years). Propensity score matching (PSM), Kaplan-Meier curves, Cox proportional hazards model and Linear regression model was applied for assessing the effects of PPIs on mortality and other outcomes during hospitalization.

RESULTS

A total of 2269 pediatric ICU patients were included, involving 1378 omeprazole (OME) users and 891 non-OME users. The results showed significant association between OME exposure and decreased ICU stay (β -0.042; 95% CI -0.073--0.011; P = 0.008) but prolonged non-ICU hospital stay (β 0.121; 95% CI 0.097-0.155; P = 0.040). No statistical significance was observed between OME exposure and reduced mortality, but the OME group had a slightly decreased tendency in 28-day mortality (HR 0.701; 95% CI 0.418-1.176) and in-hospital mortality (HR 0.726; 95% CI 0.419-1.257). Furthermore, subgroup analyses revealed that the decreased tendency of mortality were more obvious in patients less than 1 year old compared with older pediatric patients, although not statistically significant. In addition, we also observed that OME exposure was significantly associated with reduced mortality of general ICU subgroup.

CONCLUSIONS

This study provided a sign that PPIs used only in the ICU, rather than throughout hospital stay, might provide more benefit for critically ill pediatric patients. Additionally, younger pediatric patients might gain relatively more benefit than older children when receiving PPIs.

Histamine H2 receptor antagonist exhibited comparable all-cause mortality-decreasing effect as β-blockers in critically ill patients with heart failure: a cohort study

Background: Our previous study reported that histamine H2 receptor antagonists (H2RAs) exposure was associated with decreased mortality in critically ill patients with heart failure (HF) through the same pharmacological mechanism as β-blockers. However, population-based clinical study directly comparing the efficacy of H2RAs and β-blockers on mortality of HF patients are still lacking. This study aims to compare the association difference of H2RAs and β-blockers on mortality in critically ill patients with HF using the Medical Information Mart for Intensive Care III database (MIMIC-III). Methods: Study population was divided into 4 groups: β-blockers + H2RAs group, β-blockers group, H2RAs group, and Non-β-blockers + Non-H2RAs group. Kaplan-Meier curves and multivariable Cox regression models were employed to evaluate the differences of all-cause mortalities among the 4 groups. Propensity score matching (PSM) was used to increase comparability of four groups. Results: A total of 5593 patients were included. After PSM, multivariate analyses showed that patients in H2RAs group had close all-cause mortality with patients in β-blockers group. Furthermore, 30-day, 1-year, 5-year and 10-year all-mortality of patients in β-blockers + H2RAs group were significantly lower than those of patients in β-blockers group, respectively (HR: 0.64, 95%CI: 0.50-0.82 for 30-day; HR: 0.80, 95%CI: 0.69-0.93 for 1-year mortality; HR: 0.83, 95%CI: 0.74-0.93 for 5-year mortality; and HR: 0.85, 95%CI: 0.76-0.94 for 10-year mortality, respectively). Conclusion: H2RAs exposure exhibited comparable all-cause mortality-decreasing effect as β-blockers; and, furthermore, H2RAs and β-blockers had additive or synergistic interactions to improve survival in critically ill patients with HF.

Proton pump inhibitors and the risk of cardiovascular events and cardiovascular mortality: A systematic review and meta-analysis of observational studies

BACKGROUND AND AIMS

Observational research has indicated that proton pump inhibitors (PPIs) might increase the long-term risk of cardiovascular events. This study evaluated the evidence from observational studies for an effect of PPI monotherapy on the risk of incident cardiovascular events and cardiovascular mortality.

METHODS

The databases MEDLINE, EMBASE, and Scopus were systematically searched up to September 2021. The primary outcome was first cardiovascular event, i.e. first myocardial infarction or first ischaemic stroke. The secondary outcome was cardiovascular mortality. Studies were included following a detailed risk of bias assessment with the ROBINS-I tool. Sensitivity and bias analyses adjusted for potential publication bias, immortal time bias, and unmeasured confounding.

RESULTS

We included ten studies with 75,371 first cardiovascular events, as well as seven studies on cardiovascular mortality with 50,329 cardiovascular deaths in total. The pooled hazard ratios (HRs) for PPI use and cardiovascular events were 1.05 with a 95% confidence interval of (0.96; 1.15) before and 0.99 (0.93; 1.04) after adjusting for observational study design bias. The pooled HRs for PPI use and cardiovascular mortality were 1.27 (1.11; 1.44) before and 1.06 (0.96; 1.16) after adjusting for publication bias and observational study design bias.

CONCLUSION

It is questionable, whether PPI monotherapy constitutes a cardiovascular risk factor.

Impact of Acid Suppression Therapy on Renal and Survival Outcomes in Patients with Chronic Kidney Disease: A Taiwanese Nationwide Cohort Study

Histamine-2-receptor antagonist (H2RA) has shown beneficial effects on the kidney, heart, and sepsis in animal models and on the heart and COVID-19 infection in clinical studies. However, H2RAshave been used as a reference in most epidemiological studies examining the association of proton pump inhibitors (PPI) with outcomes. Therefore, we aimed to evaluate the effect of H2RA on renal and survival outcomes in chronic kidney disease (CKD) patients. We used a Taiwanese nationalhealth insurance database from 2001 to 2016 to screen 45,767 CKD patients for eligibility. We identified new users of PPI (n = 7121), H2RA (n = 48,609), and users of neither PPI nor H2RA (as controls) (n = 47,072) during follow-up, and finally created 1:1:1 propensityscore-matchedcohorts; each cohort contained 4361 patients. Participants were followed up after receivingacid-suppression agents or on the corresponding date until the occurrence of end-stage renal disease (ESRD) in the presence of competing mortality, death, or through the end of 2016. Compared toneither users, H2RAand PPI users demonstrated adjusted hazard ratios of 0.40 (95% confidence interval, 0.30–0.53) for ESRDand 0.64 (0.57–0.72) for death and 1.15 (0.91–1.45) for ESRD and 1.83 (1.65–2.03) for death, respectively. A dose-response relationship betweenH2RA use with ESRD and overall, cardiovascular, and non-cardiovascular mortality was detected. H2RA consistently provided renal and survival benefits on multivariable stratified analyses and multiple sensitivity analyses. In conclusion, dose-dependent H2RA use was associated with a reduced risk of ESRD and overall mortality in CKD patients, whereas PPI use was associated with an increased risk of overall mortality, not in a dose-dependent manner.

Effects and Safety of Oral Iron for Heart Failure with Iron Deficiency: A Systematic Review and Meta-Analysis with Trial Sequential Analysis

Background

Oral iron supplement is commonly prescribed to heart failure patients with iron deficiency. However, the effects of oral iron for heart failure remain controversial. This study included randomized controlled trials (RCTs) for meta-analysis to evaluate the effects of oral iron for heart failure patients.

Methods

Nine databases (The Cochrane Library, Embase, PubMed, CINAHL, Web of science, CNKI, SinoMed, VIP, and Wanfang) were searched for RCTs of oral iron for heart failure from inception to October 2021. The effects were assessed with a meta-analysis using Revman 5.3 software. The trial sequential analysis was performed by TSA 0.9.5.10 beta software. The risk of bias of trials was evaluated via Risk of Bias tool. The evidence quality was assessed through GRADE tool.

Results

Four studies including 582 patients with heart failure and iron deficiency were enrolled. The results indicated that oral iron treatment could improve left ventricular ejection fraction (LVEF, MD = 1.52%, 95% CI: 0.69 to 2.36, P = 0.0003) and serum ferritin (MD = 1.64, 95% CI: 0.26 to 3.02, P = 0.02). However, there was no between-group difference in the 6-minute walk distances (6MWT), N terminal pro B type natriuretic peptide (NT-proBNP) or hemoglobin level when compared with control group. Subgroup analyses revealed that the effects of oral iron on 6 MWT and serum ferritin could not be affected by duration and frequency of oral iron uptakes. In trial sequential analysis of LVEF and serum ferritin, the Z-curves crossed the traditional boundary and trail sequential monitoring boundary but did not reach the required information size.

Conclusion

This analysis showed that oral iron could improve cardiac function measured by LVEF, and iron stores measured serum ferritin, but lack of effect on exercise capacity measured by 6 MWT, and iron stores measured by hemoglobin. Given the overall poor methodological quality and evidence quality, these findings should be treated cautiously.

Histamine H2 receptor antagonist exposure was related to decreased all-cause mortality in critical ill patients with heart failure: a cohort study

BACKGROUND

Previous studies reported that histamine H2 receptor antagonists (H2RAs) had cardioprotective effects. However, the effect of H2RAs on mortality of critical ill patients with heart failure (HF) remains unclear. The aim of this study was to clarify the association between H2RAs and all-cause mortality of critical ill patients with HF based on Medical Information Mart for Intensive Care III database (MIMIC-III).

METHODS

Propensity score matching (PSM) was applied to account for the baseline differences between two groups that exposed to H2RAs or not. The study primary outcome was all-cause mortality. Kaplan-Meier curves and multivariable Cox regression models were employed to estimate the effects of H2RAs on mortality of critical ill patients with HF.

RESULTS

A total of 10 387 patients were included, involving 4440 H2RAs users and 5947 non-H2RAs users. After matching, 3130 pairs of patients were matched between H2RAs users and non-H2RAs users. The results showed significant association between H2RAs exposure and decreased 30-day, 90-day and 1-year mortality in both univariate analyses and multivariate analyses (HR = 0.73, 95%CI: 0.65-0.83 for 30-day; HR = 0.80, 95%CI: 0.72-0.89 for 90-day; and HR = 0.83, 95%CI: 0.76-0.90 for 1-year mortality, respectively) by Cox regression after PSM. Furthermore, stratified analyses revealed that the 30-day, 90-day and 1-year mortality of ranitidine users were significantly lower than those of famotidine users, respectively.

CONCLUSIONS

H2RAs exposure was associated with lower mortality in critical ill patients with HF. Furthermore, ranitidine might be superior to famotidine in reducing mortality of critical ill patients with HF.

Histamine H2 Receptor Antagonists and Heart Failure Risk in Postmenopausal Women: The Women's Health Initiative

Background Prior studies suggested lower risk of heart failure (HF) in individuals taking H2 receptor antagonists (H2RA) compared with H2RA nonusers in relatively small studies. We evaluated the association of H2RA use and incident HF in postmenopausal women in the large-scale WHI (Women's Health Initiative) study. Methods and Results This study included postmenopausal women from the WHI without a history of HF at baseline. HF was defined as first incident hospitalization for HF and physician adjudicated. Multivariable Cox proportional hazards regression models evaluated the association of H2RA use as a time-varying exposure with HF risk, after adjustment for demographic, lifestyle, and medical history variables. Sensitivity analyses examined (1) risk of HF stratified by the ARIC (Atherosclerosis Risk in Communities) score, (2) propensity score matching on H2RA use, (3) use of proton pump inhibitors rather than H2RA nonuse as the referent, and (4) exclusion of those taking diuretics at baseline. The primary analysis included 158 854 women after exclusion criteria, of whom 9757 (6.1%) were H2RA users. During median 8.2 years of follow-up, 376 H2RA users (4.9 events/1000 person-years) and 3206 nonusers (2.7 events/1000 person-years) developed incident HF. After multivariable adjustment, there was no association between H2RA use and HF in the primary analysis (hazard ratio, 1.07; 95% CI, 0.94-1.22; P=0.31) or in any of the sensitivity analyses. Conclusions Clinical H2RA use was not associated with incident HF among postmenopausal women. Future studies are needed to evaluate potential effect modification by sex, HF severity, or patterns of use on H2RA exposure and HF risk. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT00000611.

The Roles of Cardiovascular H2-Histamine Receptors Under Normal and Pathophysiological Conditions

This review addresses pharmacological, structural and functional relationships among H₂-histamine receptors and H₁-histamine receptors in the mammalian heart. The role of both receptors in the regulation of force and rhythm, including their electrophysiological effects on the mammalian heart, will then be discussed in context. The potential clinical role of cardiac H₂-histamine-receptors in cardiac diseases will be examined. The use of H₂-histamine receptor agonists to acutely increase the force of contraction will be discussed. Special attention will be paid to the potential role of cardiac H₂-histamine receptors in the genesis of cardiac arrhythmias. Moreover, novel findings on the putative role of H₂-histamine receptor antagonists in treating chronic heart failure in animal models and patients will be reviewed. Some limitations in our biochemical understanding of the cardiac role of H₂-histamine receptors will be discussed. Recommendations for further basic and translational research on cardiac H₂-histamine receptors will be offered. We will speculate whether new knowledge might lead to novel roles of H₂-histamine receptors in cardiac disease and whether cardiomyocyte specific H₂-histamine receptor agonists and antagonists should be developed.

Histamine receptors in heart failure

The biogenic amine, histamine, is found predominantly in mast cells, as well as specific histaminergic neurons. Histamine exerts its many and varied actions via four G-protein-coupled receptors numbered one through four. Histamine has multiple effects on cardiac physiology, mainly via the histamine 1 and 2 receptors, which on a simplified level have opposing effects on heart rate, force of contraction, and coronary vasculature function. In heart failure, the actions of the histamine receptors are complex, the histamine 1 receptor appears to have detrimental actions predominantly in the coronary vasculature, while the histamine 2 receptor mediates adverse effects on cardiac remodeling via actions on cardiomyocytes, fibroblasts, and even endothelial cells. Conversely, there is growing evidence that the histamine 3 receptor exerts protective actions when activated. Little is known about the histamine 4 receptor in heart failure. Targeting histamine receptors as a therapeutic approach for heart failure is an important area of investigation given the over-the-counter access to many compounds targeting these receptors, and thus the relatively straight forward possibility of drug repurposing. In this review, we briefly describe histamine receptor signaling and the actions of each histamine receptor in normal cardiac physiology, before describing in more detail the known role of each histamine receptor in adverse cardiac remodeling and heart failure. This includes information from both clinical studies and experimental animal models. It is the goal of this review article to bring more focus to the possibility of targeting histamine receptors as therapy for heart failure.

Histamine 2 receptors in cardiovascular biology: A friend for the heart

Undermining new mediators involved in the development and progression of cardiovascular diseases (CVDs) is vital for better disease management. Existing studies implicate a crucial role for inflammation and inflammatory cells, particularly mast cells, in cardiac diseases. Interestingly, the mast cell mediator, histamine, and its receptors profoundly impact the pathophysiology of the heart, resulting in hypertension-induced cardiac hypertrophy and other cardiac anomalies. In this review, we provide a detailed description of mast cell activation, mediators, and histamine receptors, with a particular focus on histamine 2 receptors (H2Rs). Preclinical and clinical studies using histamine receptor antagonists report improvement in cardiac function. Insights into the precise function of histamine receptors will aid in developing novel therapies and pave the way for repurposing antihistamines for cardiovascular diseases.

Histamine

Histamine has at least twenty-three known physiological functions, including playing a prominent role in immunologically mediated inflammation. The structure and metabolism of histamine is discussed, together with the various types of histamine receptors. Histamine plays a role in anaphylaxis, mast cell activation syndromes and mastocytosis and these conditions are relevant to anaesthetic practice. The antihistamine drugs and the H2 receptors agonists are discussed with regard to their role in anaesthesia.

Hypochlorhydria reduces mortality in heart failure caused by Kcne2 gene deletion

Heart failure (HF) is an increasing global health crisis, affecting 40 million people and causing 50% mortality within 5 years of diagnosis. A fuller understanding of the genetic and environmental factors underlying HF, and novel therapeutic approaches to address it, are urgently warranted. Here, we discovered that cardiac-specific germline deletion in mice of potassium channel β subunit-encoding Kcne2 (Kcne2^CS-/- ) causes dilated cardiomyopathy and terminal HF (median longevity, 28 weeks). Mice with global Kcne2 deletion (Kcne2^Glo-/- ) exhibit multiple HF risk factors, yet, paradoxically survived over twice as long as Kcne2^CS-/- mice. Global Kcne2 deletion, which inhibits gastric acid secretion, reduced the relative abundance of species within Bacteroidales, a bacterial order that positively correlates with increased lifetime risk of human cardiovascular disease. Strikingly, the proton-pump inhibitor omeprazole similarly altered the microbiome and delayed terminal HF in Kcne2^CS-/- mice, increasing survival 10-fold at 44 weeks. Thus, genetic or pharmacologic induction of hypochlorhydria and decreased gut Bacteroidales species are associated with lifespan extension in a novel HF model.