A Randomized, Controlled Trial of the Effect of Allopurinol on Left Ventricular Mass Index in Hemodialysis Patients

Dosing practices, pharmacokinetics, and effectiveness of allopurinol in gout patients receiving dialysis: a scoping review

Urate and oxypurinol, allopurinol's active metabolite, are predominantly eliminated by the kidneys. Therefore, optimising allopurinol dosing in patients on dialysis is challenging. This review explores allopurinol dosing practices, oxypurinol pharmacokinetics, and effectiveness in gout patients receiving haemodialysis or peritoneal dialysis (PD). Five databases and grey literature were searched. Studies on gout patients on allopurinol, receiving dialysis, and reporting dosing, pharmacokinetics, or effectiveness (reduction in urate and/or gout flares) were included. Abstract, full text screening and data extraction were done by two authors. Studies were grouped by dialysis modality. Eighteen studies were identified including 390 patients, most (n = 274, 70%) on haemodialysis with allopurinol administered after dialysis. The peritoneal dialytic clearance of oxypurinol (3.14 mL/min, n = 5) and urate (2.7-4 mL/min, n = 25) was similar. The haemodialytic clearance was 78-137 mL/min for oxypurinol (n = 21) and 80-165 mL/min for urate (n = 19). Allopurinol doses were higher in haemodialysis (100-600 mg/day) than PD (110-125 mg/day). Haemodialysis sessions decreased oxypurinol and urate concentrations by 39-57% (n = 30) and 56-71% (n = 6), respectively. Over time (1-230 days), urate concentrations in haemodialysis (n = 85) reduced by 14-41%. Target serum urate (< 0.36 mmol/L) was achieved in 61% (20/33) and 47% (13/28) of haemodialysis and PD patients, respectively. Gout flares decreased from 2 to 0.1 attacks/year in patients receiving dialysis (n = 79). Oxypurinol and urate clearance by haemodialysis was higher than PD, necessitating higher doses of allopurinol. POST dialysis allopurinol doses titrated to target urate are suggested. Future studies considering the impact of dialysis modality on allopurinol dose requirements are needed.

Allopurinol use and risk of acute coronary syndrome in gout patients: a population-based cohort study in Sweden

OBJECTIVES

To investigate the impact of allopurinol use on the risk of first-ever acute coronary syndrome (ACS) event in patients with gout.

METHODS

Using national and regional register data, we included all patients with a gout diagnosis at primary or specialised care in Western Sweden in the period 2007-2017 (n=18 862; 67% male patients). Patients with a prior history of coronary heart disease (CHD) were excluded. Follow-up started at the first gout diagnosis and ended at the first-ever ACS event, death or study end. The main outcome was the risk of first-ever ACS in: (1) allopurinol users versus non-users, by defining three categories of allopurinol exposure: exposed to 100 mg, >100 mg and no exposure (reference) and (2) allopurinol initiators (within 125 days) versus long-term users (reference). Multivariable logistic regression analysis was used to calculate ORs and 95% CIs.

RESULTS

In analysis 1 (n=18 862), 15.3% (n=2892) were exposed to 100 mg, 9.1% (n=1717) to >100 mg and 75.6% (n=14 253) were not exposed. Allopurinol users were older and had more comorbidities compared with non-users. Allopurinol exposure (100 mg and >100 mg) was associated with significantly lower odds of first-ever ACS (OR 0.77; 95% CI 0.63 to 0.94, and OR 0.61; 95% CI 0.47 to 0.81, respectively). In Analysis 2, allopurinol initiators (n=489) had significantly higher odds of first-ever ACS compared with long-term users (n=2916) (OR 1.68; 95% CI 1.03 to 2.75).

CONCLUSIONS

In patients with gout and without CHD, long-term allopurinol use protects against first-ever ACS compared with non-users. In contrast, allopurinol initiators, possibly having more systemic inflammation, had a higher risk of first-ever ACS compared with long-term users.

Allopurinol and cardiovascular outcomes in patients with ischaemic heart disease: the ALL-HEART RCT and economic evaluation

Background

Allopurinol is a xanthine oxidase inhibitor that lowers serum uric acid and is used to prevent acute gout flares in patients with gout. Observational and small interventional studies have suggested beneficial cardiovascular effects of allopurinol.

Objective

To determine whether allopurinol improves major cardiovascular outcomes in patients with ischaemic heart disease.

Design

Prospective, randomised, open-label, blinded endpoint multicentre clinical trial.

Setting

Four hundred and twenty-four UK primary care practices.

Participants

Aged 60 years and over with ischaemic heart disease but no gout.

Interventions

Participants were randomised (1 : 1) using a central web-based randomisation system to receive allopurinol up to 600 mg daily that was added to usual care or to continue usual care.

Main outcome measures

The primary outcome was the composite of non-fatal myocardial infarction, non-fatal stroke or cardiovascular death. Secondary outcomes were non-fatal myocardial infarction, non-fatal stroke, cardiovascular death, all-cause mortality, hospitalisation for heart failure, hospitalisation for acute coronary syndrome, coronary revascularisation, hospitalisation for acute coronary syndrome or coronary revascularisation, all cardiovascular hospitalisations, quality of life and cost-effectiveness. The hazard ratio (allopurinol vs. usual care) in a Cox proportional hazards model was assessed for superiority in a modified intention-to-treat analysis.

Results

From 7 February 2014 to 2 October 2017, 5937 participants were enrolled and randomised to the allopurinol arm (n = 2979) or the usual care arm (n = 2958). A total of 5721 randomised participants (2853 allopurinol; 2868 usual care) were included in the modified intention-to-treat analysis population (mean age 72.0 years; 75.5% male). There was no difference between the allopurinol and usual care arms in the primary endpoint, 314 (11.0%) participants in the allopurinol arm (2.47 events per 100 patient-years) and 325 (11.3%) in the usual care arm (2.37 events per 100 patient-years), hazard ratio 1.04 (95% confidence interval 0.89 to 1.21); p = 0.65. Two hundred and eighty-eight (10.1%) participants in the allopurinol arm and 303 (10.6%) participants in the usual care arm died, hazard ratio 1.02 (95% confidence interval 0.87 to 1.20); p = 0.77. The pre-specified health economic analysis plan was to perform a 'within trial' cost-utility analysis if there was no statistically significant difference in the primary endpoint, so NHS costs and quality-adjusted life-years were estimated over a 5-year period. The difference in costs between treatment arms was +£115 higher for allopurinol (95% confidence interval £17 to £210) with no difference in quality-adjusted life-years (95% confidence interval -0.061 to +0.060). We conclude that there is no evidence that allopurinol used in line with the study protocol is cost-effective.

Limitations

The results may not be generalisable to younger populations, other ethnic groups or patients with more acute ischaemic heart disease. One thousand six hundred and thirty-seven participants (57.4%) in the allopurinol arm withdrew from randomised treatment, but an on-treatment analysis gave similar results to the main analysis.

Conclusions

The ALL-HEART study showed that treatment with allopurinol 600 mg daily did not improve cardiovascular outcomes compared to usual care in patients with ischaemic heart disease. We conclude that allopurinol should not be recommended for the secondary prevention of cardiovascular events in patients with ischaemic heart disease but no gout.

Future work

The effects of allopurinol on cardiovascular outcomes in patients with ischaemic heart disease and co-existing hyperuricaemia or clinical gout could be explored in future studies.

Trial registration

This trial is registered as EU Clinical Trials Register (EudraCT 2013-003559-39) and ISRCTN (ISRCTN 32017426).

Funding

This award was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme (NIHR award ref: 11/36/41) and is published in full in Health Technology Assessment; Vol. 28, No. 18. See the NIHR Funding and Awards website for further award information.

Efficacy of Allopurinol in Improving Endothelial Dysfunction: A Systematic Review and Meta-Analysis

INTRODUCTION

Endothelial dysfunction has been implicated in various cardiovascular disorders as the initial pathology. Allopurinol has been shown to improve endothelial dysfunction in patients with gout, but its effect on cardiovascular patients is unclear.

AIMS

We aim to assess allopurinol efficacy in improving endothelial dysfunction overall and in different disease states including but not limited to heart failure, chronic kidney disease, ischemic heart disease METHODS: We conducted a literature search of PubMed, Cochrane's Central Library, and Scopus until December 2022, including randomized controlled trials and double-arm observational studies. The primary outcome measure was endothelial function assessed by change in flow mediated dilation (FMD) RESULTS: Our meta-analysis included 22 studies with a total of 1472 patients. Our pooled analysis shows that allopurinol significantly improved FMD (WMD = 1.46%, 95% CI [0.70, 2.22], p < 0.01) compared to control. However, there was no significant difference between allopurinol and control for endothelial-independent vasodilation measured by forearm blood flow (WMD = 0.10%, 95% CI [- 0.89, 0.69], p = 0.80). Subgroup analysis indicated that the effect of allopurinol on FMD was more significant in diabetic and congestive heart failure patients.

CONCLUSION

While allopurinol may improve endothelial function in various patient populations, further high-quality randomized controlled trials are needed to determine its efficacy in preventing cardiovascular disease exacerbation.

Major cardiovascular events and associated factors among routine hemodialysis patients with end-stage renal disease at tertiary care hospital in Somalia

Introduction

Cardiovascular complications are the most significant cause of death in patients undergoing routine hemodialysi (HD) with end-stage renal disease (ESRD). The main objective of this study is to determine the significant cardiac events and risk factors in patients undergoing routine hemodialysis in Somalia.

Methods

We carried out a cross-sectional retrospective study in a single dialysis center in Somalia. Two hundred out of 224 were included. All of them had ESRD and were on hemodialysis during the study period between May and October 2021. The records of all patients were reviewed, and the following parameters were analyzed socio-demographic factors, risk factors for cardiovascular disease, and the presence of cardiovascular diseases.

Results

The mean age was 54 ± 17.5 years (range 18-88 years), and 106 (53%) patients were males. The prevalence of a cardiovascular disease among hemodialysis patients was 29.5%. Moreover, the distribution of cardiovascular diseases was different; heart failure was the most common, about 27.1%, followed by coronary artery disease (17%), pericarditis and pericardial-effusion (13.6%), dysrhythmia (10.2%), cerebrovascular-accident (8.5%), and peripheral vascular disease (3.4%). About 176 (88%) participants had at least one modifiable cardiovascular risk factor. The most common modifiable cardiovascular risk factor was hypertension (n = 45, 25.1%), followed by anemia (n = 28, 15.6%) and diabetes (n = 26, 14.5%). Younger (18-30) participants were six times less likely to have cardiovascular events among hemodialysis than older age 0.4 (0.11-1.12).

Conclusion

Low prevalence rate of cardiovascular complications was confirmed in ESRD patients receiving hemodialysis in the main HD center in Somalia. Diabetes, anemia, and hypertension were the highest significant risk factors for CVD in HD patients with ESRD in Somalia.

Endothelial Cell Dysfunction and Increased Cardiovascular Risk in Patients With Chronic Kidney Disease

The endothelium is considered to be the gatekeeper of the vessel wall, maintaining and regulating vascular integrity. In patients with chronic kidney disease, protective endothelial cell functions are impaired due to the proinflammatory, prothrombotic and uremic environment caused by the decline in kidney function, adding to the increase in cardiovascular complications in this vulnerable patient population. In this review, we discuss endothelial cell functioning in healthy conditions and the contribution of endothelial cell dysfunction to cardiovascular disease. Further, we summarize the phenotypic changes of the endothelium in chronic kidney disease patients and the relation of endothelial cell dysfunction to cardiovascular risk in chronic kidney disease. We also review the mechanisms that underlie endothelial changes in chronic kidney disease and consider potential pharmacological interventions that can ameliorate endothelial health.

Uric Acid, Ferritin, Albumin, Parathyroid Hormone and Gamma-Glutamyl Transferase Concentrations are Associated with Uremic Cardiomyopathy Characteristics in Non-Dialysis and Dialysis Chronic Kidney Disease Patients

Introduction

Circulating uric acid, ferritin, albumin, intact parathyroid hormone and gamma-glutamyl transferase each participate in biochemical reactions that reduce or/and enhance oxidative stress, which is considered the final common pathway through which pathophysiological mechanisms cause uremic cardiomyopathy. We hypothesized that the respective biomarkers may be involved in the development of uremic cardiomyopathy characteristics and can be useful in their identification among chronic kidney disease patients.

Methods

We assessed traditional and non-traditional cardiovascular risk factors including biomarker concentrations and determined central systolic blood pressure using SphygmoCor software and cardiac structure and function by echocardiography in 109 (64 non-dialysis and 45 dialysis) patients. Associations were evaluated in multivariate regression models and receiver operator characteristic (ROC) curve analysis.

Results

Each biomarker concentration was associated with left ventricular mass beyond stroke work and/or inappropriate left ventricular mass in all, non-dialysis and/or dialysis patients. Ferritin, albumin and gamma-glutamyl transferase levels were additionally associated with E/e' in all, non-dialysis and/or dialysis patients. Dialysis status influenced the relationship of uric acid concentrations with inappropriate left ventricular mass and those of gamma-glutamyl transferase levels with left ventricular mass and inappropriate left ventricular mass. In stratified analysis, low uric acid levels were related to inappropriate left ventricular mass in dialysis but not non-dialysis patients (interaction p=0.001) whereas gamma-glutamyl transferase concentrations were associated with left ventricular mass and inappropriate left ventricular mass in non-dialysis but not dialysis patients (interaction p=0.020 to 0.036). In ROC curve analysis, uric acid (area under the curve (AUC)=0.877), ferritin (AUC=0.703) and albumin (AUC=0.728) concentrations effectively discriminated between dialysis patients with and without inappropriate left ventricular hypertrophy, left ventricular hypertrophy, and increased E/e,' respectively.

Conclusion

Uric acid, ferritin, albumin, parathyroid hormone and gamma-glutamyl transferase were associated with uremic cardiomyopathy characteristics and could be useful in their identification. Our findings merit validation in future longitudinal studies.

Left ventricular dysfunction with preserved ejection fraction: the most common left ventricular disorder in chronic kidney disease patients

Chronic kidney disease (CKD) is a risk factor for premature cardiovascular disease. As kidney function declines, the presence of left ventricular abnormalities increases such that by the time kidney replacement therapy is required with dialysis or kidney transplantation, more than two-thirds of patients have left ventricular hypertrophy. Historically, much research in nephrology has focussed on the structural and functional aspects of cardiac disease in CKD, particularly using echocardiography to describe these abnormalities. There is a need to translate knowledge around these imaging findings to clinical outcomes such as unplanned hospital admission with heart failure and premature cardiovascular death. Left ventricular hypertrophy and cardiac fibrosis, which are common in CKD, predispose to the clinical syndrome of heart failure with preserved left ventricular ejection fraction (HFpEF). There is a bidirectional relationship between CKD and HFpEF, whereby CKD is a risk factor for HFpEF and CKD impacts outcomes for patients with HFpEF. There have been major improvements in outcomes for patients with heart failure and reduced left ventricular ejection fraction as a result of several large randomized controlled trials. Finding therapy for HFpEF has been more elusive, although recent data suggest that sodium-glucose cotransporter 2 inhibition offers a novel evidence-based class of therapy that improves outcomes in HFpEF. These observations have emerged as this class of drugs has also become the standard of care for many patients with proteinuric CKD, suggesting that there is now hope for addressing the combination of HFpEF and CKD in parallel. In this review we summarize the epidemiology, pathophysiology, diagnostic strategies and treatment of HFpEF with a focus on patients with CKD.

Allopurinol versus usual care in UK patients with ischaemic heart disease (ALL-HEART): a multicentre, prospective, randomised, open-label, blinded-endpoint trial

BACKGROUND

Allopurinol is a urate-lowering therapy used to treat patients with gout. Previous studies have shown that allopurinol has positive effects on several cardiovascular parameters. The ALL-HEART study aimed to determine whether allopurinol therapy improves major cardiovascular outcomes in patients with ischaemic heart disease.

METHODS

ALL-HEART was a multicentre, prospective, randomised, open-label, blinded-endpoint trial done in 18 regional centres in England and Scotland, with patients recruited from 424 primary care practices. Eligible patients were aged 60 years or older, with ischaemic heart disease but no history of gout. Participants were randomly assigned (1:1), using a central web-based randomisation system accessed via a web-based application or an interactive voice response system, to receive oral allopurinol up-titrated to a dose of 600 mg daily (300 mg daily in participants with moderate renal impairment at baseline) or to continue usual care. The primary outcome was the composite cardiovascular endpoint of non-fatal myocardial infarction, non-fatal stroke, or cardiovascular death. The hazard ratio (allopurinol vs usual care) in a Cox proportional hazards model was assessed for superiority in a modified intention-to-treat analysis (excluding randomly assigned patients later found to have met one of the exclusion criteria). The safety analysis population included all patients in the modified intention-to-treat usual care group and those who took at least one dose of randomised medication in the allopurinol group. This study is registered with the EU Clinical Trials Register, EudraCT 2013-003559-39, and ISRCTN, ISRCTN32017426.

FINDINGS

Between Feb 7, 2014, and Oct 2, 2017, 5937 participants were enrolled and then randomly assigned to receive allopurinol or usual care. After exclusion of 216 patients after randomisation, 5721 participants (mean age 72·0 years [SD 6·8], 4321 [75·5%] males, and 5676 [99·2%] white) were included in the modified intention-to-treat population, with 2853 in the allopurinol group and 2868 in the usual care group. Mean follow-up time in the study was 4·8 years (1·5). There was no evidence of a difference between the randomised treatment groups in the rates of the primary endpoint. 314 (11·0%) participants in the allopurinol group (2·47 events per 100 patient-years) and 325 (11·3%) in the usual care group (2·37 events per 100 patient-years) had a primary endpoint (hazard ratio [HR] 1·04 [95% CI 0·89-1·21], p=0·65). 288 (10·1%) participants in the allopurinol group and 303 (10·6%) participants in the usual care group died from any cause (HR 1·02 [95% CI 0·87-1·20], p=0·77).

INTERPRETATION

In this large, randomised clinical trial in patients aged 60 years or older with ischaemic heart disease but no history of gout, there was no difference in the primary outcome of non-fatal myocardial infarction, non-fatal stroke, or cardiovascular death between participants randomised to allopurinol therapy and those randomised to usual care.

FUNDING

UK National Institute for Health and Care Research.

Association between Anti-Erythropoietin Receptor Antibodies and Cardiac Function in Patients on Hemodialysis: A Multicenter Cross-Sectional Study

Cardiac dysfunction is an important prognostic predictor of cardiovascular mortality in patients on hemodialysis (HD). Erythropoietin (EPO) has been reported to improve cardiac function by binding to the EPO receptor (EPOR) on cardiomyocytes. This study investigated whether anti-EPOR antibodies were associated with left ventricular cardiac function in patients undergoing HD. This multicenter, cross-sectional observational study included 377 patients (median age, 70 years; 267 (70.8%) males) with chronic kidney disease (CKD) undergoing stable maintenance HD. Serum levels of anti-EPOR antibodies were measured, and echocardiography was used to assess the left ventricular mass index (LVMI) and left ventricular ejection fraction (LVEF). Anti-EPOR antibodies were found in 17 patients (4.5%). LVMI was greater (median of 135 g/m2 vs. 115 g/m2, p = 0.042), and the prevalence of LVEF < 50% was higher (35.3% vs. 15.6%, p = 0.032) in patients with anti-EPOR antibodies than in those without. Multivariable linear regression and logistic regression analysis (after adjusting for known risk factors of heart failure) revealed that anti-EPOR antibodies were independently associated with LVMI (coefficient 16.2%; 95% confidence interval (CI) 1.0−35.0%, p = 0.043) and LVEF <50% (odds ratio 3.20; 95% CI 1.05−9.73, p = 0.041). Thus, anti-EPOR antibody positivity was associated with left ventricular dysfunction in patients undergoing HD.

Left ventricular mass regression, all-cause and cardiovascular mortality in chronic kidney disease: a meta-analysis

Background

Cardiovascular disease is an important driver of the increased mortality associated with chronic kidney disease (CKD). Higher left ventricular mass (LVM) predicts increased risk of adverse cardiovascular outcomes and total mortality, but previous reviews have shown no clear association between intervention-induced LVM change and all-cause or cardiovascular mortality in CKD.

Methods

The primary objective of this meta-analysis was to investigate whether treatment-induced reductions in LVM over periods ≥12 months were associated with all-cause mortality in patients with CKD. Cardiovascular mortality was investigated as a secondary outcome. Measures of association in the form of relative risks (RRs) with associated variability and precision (95% confidence intervals [CIs]) were extracted directly from each study, when reported, or were calculated based on the published data, if possible, and pooled RR estimates were determined.

Results

The meta-analysis included 42 trials with duration ≥12 months: 6 of erythropoietin stimulating agents treating to higher vs. lower hemoglobin targets, 10 of renin-angiotensin-aldosterone system inhibitors vs. placebo or another blood pressure lowering agent, 14 of modified hemodialysis regimens, and 12 of other types of interventions. All-cause mortality was reported in 121/2584 (4.86%) subjects in intervention groups and 168/2606 (6.45%) subjects in control groups. The pooled RR estimate of the 27 trials ≥12 months with ≥1 event in ≥1 group was 0.72 (95% CI 0.57 to 0.90, p = 0.005), with little heterogeneity across studies. Directionalities of the associations in intervention subgroups were the same. Sensitivity analyses of ≥6 months (34 trials), ≥9 months (29 trials), and >12 months (10 trials), and including studies with no events in either group, demonstrated similar risk reductions to the primary analysis. The point estimate for cardiovascular mortality was similar to all-cause mortality, but not statistically significant: RR 0.67, 95% CI 0.39 to 1.16.

Conclusions

These results suggest that LVM regression may be a useful surrogate marker for benefits of interventions intended to reduce mortality risk in patients with CKD.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12882-022-02666-1.