Non-valvular atrial fibrillation in patients on peritoneal dialysis, prevalence, treatment and professionals involved

Atrial fibrillation is the most frequent chronic arrhythmia in patients with chronic kidney disease. Oral anticoagulation with vitamin K antagonists and now direct oral anticoagulants have been and are the fundamental pillars for the prevention of thromboembolic events. However, there are no randomized clinical trials on the risk-benefit profile of oral anticoagulation in patients with chronic kidney disease stage 5 on peritoneal dialysis and there is little evidence in the literature in this population. The objective of our study was to know the prevalence, treatment and professionals involved in the management of atrial fibrillation in peritoneal dialysis patients. For this purpose, we performed a descriptive analysis through a survey sent to different peritoneal dialysis units in Spain. A total of 1,403 patients on peritoneal dialysis were included in the study, of whom 186 (13.2%) had non-valvular atrial fibrillation. In addition, the assessment of the scores of thromboembolic and bleeding risks for the indication of oral anticoagulation was mainly carried out by the cardiologist (60% of the units), as well as its prescription (cardiologist 47% or in consensus with the nephrologist 43%). In summary, patients on peritoneal dialysis have a remarkable prevalence of non-valvular atrial fibrillation. Patients frequently receive oral anticoagulation with vitamin K antagonists, as well as direct oral anticoagulants. The data obtained regarding the scores used for the assessment of thromboembolic and bleeding risk, treatment and involvement by Nephrology indicates that there is a need for training and involvement of the nephrologist in this pathology.

The Association of Atrial Fibrillation and Ischemic Stroke in Patients on Hemodialysis: A Competing Risk Analysis

Background

Stroke is common in patients with end-stage renal disease (ESRD) treated with hemodialysis (HD) and associated with high mortality rate. In the general population, atrial fibrillation (AF) is a major risk factor for stroke and therapeutic anticoagulation is associated with risk reduction, whereas in ESRD the relationship is less clear.

Objective

The purpose of this study is to demonstrate the influence of AF on stroke rates and probability in those on HD following competing risk analyses.

Design

A national record linkage cohort study.

Setting

All renal and stroke units in Scotland, UK.

Patients

All patients with ESRD receiving HD within Scotland from 2005 to 2013 (follow-up to 2015).

Measurements

Demographic, clinical, and laboratory data were linked between the Scottish Renal Registry, Scottish Stroke Care Audit, and hospital discharge data. Stroke was defined as a fatal or nonfatal event and mortality derived from national records.

Methods

Associations for stroke were determined using competing risk models: the cause-specific hazards model and the Fine and Gray subdistribution hazards model accounting for the competing risk of death in models of all stroke, ischemic stroke, and first-ever stroke.

Results

Of 5502 patients treated with HD with 12 348.6-year follow-up, 363 (6.6%) experienced stroke. The stroke incidence rate was 26.7 per 1000 patient-years. Multivariable regression on the cause-specific hazard for stroke demonstrated age, hazard ratio (HR) (95% confidence interval [CI]) = 1.04 (1.03-1.05); AF, HR (95% CI) = 1.88 (1.25-2.83); prior stroke, HR (95% CI) = 2.29 (1.48-3.54), and diabetes, HR (95% CI) = 1.92 (1.45-2.53); serum phosphate, HR (95% CI) = 2.15 (1.56-2.99); lower body weight, HR (95% CI) = 0.99 (0.98-1.00); lower hemoglobin, HR (95% CI) = 0.88 (0.77-0.99); and systolic blood pressure (BP), HR (95% CI) = 1.01 (1.00-1.02), to be associated with an increased stroke rate. In contrast, the subdistribution HRs obtained following Fine and Gray regression demonstrated that AF, weight, and hemoglobin were not associated with stroke risk. In both models, AF was significantly associated with nonstroke death.

Limitations

Our analyses derive from retrospective data sets and thus can only describe association not causation. Data on anticoagulant use are not available.

Conclusions

The incidence of stroke in HD patients is high. The competing risk of "prestroke" mortality affects the relationship between AF and risk of future stroke. Trial designs for interventions to reduce stroke risk in HD patients, such as anticoagulation for AF, should take account of competing risks affecting associations between risk factors and outcomes.

Atrial fibrillation in dialysis patients: is there a place for non-vitamin K antagonist oral anticoagulants?

Atrial fibrillation (AF) occurs approximately in 3% of general population, with greater prevalence in elderly. Non-vitamin K-dependent oral anticoagulant agents (NOACs) according to the current European guidelines are recommended for patients with AF at high risk for stroke as a first-choice treatment. NOACs are not inferior to warfarin or some of them are better than warfarin in reducing the rate of ischemic stroke. Moreover, they significantly reduce the rate of intracranial hemorrhages, major bleedings, and mortality compared with warfarin. Nevertheless according to ESC guidelines, NOACs are not recommended in patients with creatinine clearance < 30 mL/min. Observational studies provide contradictive data. Only few new trials are ongoing. Therefore, it is not clear if NOACs should be in the future prescribed to patients with advanced CKD and those on dialysis. Moreover, the risk of stroke and bleeding is much higher in such population than in patients without end-stage renal disease (ESRD). The authors provide data on pros and cons of use of NOACs in ESRD patients with AF.

Impact of Chronic Kidney Disease on the Presentation and Outcome of Patients Hospitalized With Atrial Fibrillation: Insights From Qatar

Atrial fibrillation (AF) with coexistent chronic kidney disease (CKD) is poorly described in the literature. We compared the presenting symptoms, clinical characteristics, treatment, and outcome of patients hospitalized with AF with and without CKD in a large clinical registry. Data of patients hospitalized with AF between 1991 and 2012 in Qatar were analyzed. Of 5201 patients hospitalized for AF, 264 (5.1%) had CKD. Patients with AF and CKD were older with higher prevalence of other comorbidities and left ventricular dysfunction and were more likely to present with shortness of breath and chest pain compared with patients with AF alone who were more likely to present with palpitation. The crude in-hospital mortality was 3 times higher in patients with dual disease. On multivariable adjustments, CKD was an independent predictor of mortality (odds ratio: 2.84; 95% confidence interval: 1.33-6.08, P = .001). Further studies are warranted to try to reduce the increased mortality observed in this high-risk population.

Atrial fibrillation in dialysis patients: time to abandon warfarin?

Atrial fibrillation (AF) is a frequent clinical complication in dialysis patients, and warfarin therapy represents the most common approach for reducing the risk of stroke in this population. However, current evidence based on observational studies, offer conflicting results, whereas no randomized controlled trials have been carried out so far. Additionally, many clinicians are wary of the possible role of warfarin as vascular calcification inducer and its potential to increase the high risk of bleeding among patients on dialysis. Ideally the most promising therapy would be based on direct inhibitors of factor IIa or Xa; however, at the moment, none of these drugs can be safely prescribed in dialysis patients, because of their potentially dangerous accumulation, and the lack of sufficient experience with apixaban or rivaroxaban, two drugs showing a favorable pharmacokinetic profile in end-stage renal disease. Hence, the use of vitamin K inhibitors is currently the only pharmacological option for stroke prevention in dialysis patients with atrial fibrillation, leaving the clinicians in a management conundrum.This review discusses the trade-offs implicated in warfarin use for this population, the promises of newly developed drugs, the role of dialysis as atrial fibrillation trigger, as well as potential non-pharmacological management options suitable in selected clinical situations.

Anti-coagulation, anti-platelets or no therapy in haemodialysis patients with atrial fibrillation: A decision analysis

BACKGROUND

Optimal treatment of atrial fibrillation (AF) in the haemodialysis population is uncertain due to the exclusion of this group from randomized trials. The risk-benefit profile for anticoagulation and anti-platelet therapy in haemodialysis differs from the general population due to platelet dysfunction from uraemia, altered pharmacokinetics and increased falls risk.

METHODS

This decision analysis used a Markov-state transition model that took a patient perspective over a 5 year timeframe. The Markov model compared life-years gained and quality-adjusted life-years gained (QALY) for three AF treatment strategies: warfarin, aspirin and no treatment. The base case was a 70-year-old man on haemodialysis with non-valvular AF.

RESULTS

In the base case, the total health outcomes in life-years and QALY were 2.37 and 1.47 respectively for warfarin, 2.38 and 1.61 respectively for aspirin, and 2.39 and 1.61 respectively for no treatment. Thus, warfarin led to 0.14 fewer QALY or 1.7 fewer months of life lived in full health, compared with either aspirin or no therapy. The finding that warfarin generated the lowest expected QALY was robust to one-way, two-way and probabilistic sensitivity analyses.

CONCLUSIONS

Our results suggest that warfarin should not be the default choice for older haemodialysis patients with non-valvular AF as it provides the fewest QALY compared with aspirin or no therapy.

Ischaemic stroke in incident dialysis patients

BACKGROUND

Despite the high frequency of cardiovascular disease among the population on dialysis, there are few studies on ischaemic stroke and associated factors. The objective of the present study is to assess the prevalence of ischaemic stroke at the start of dialysis, its incidence in the course of follow-up and possible factors associated in its presentation.

METHODS

All patients in our dialysis programme between 1 January 1999 and 31 December 2005 were included in the study and followed up until death, transplant, transfer out of our catchment area, or conclusion of the study on 31 December 2008. Factors analysed were age, gender, smoking habit, diabetes, hypertension, previous ischaemic stroke, ischaemic coronary disease, peripheral vascular disease and atrial fibrillation. Other factors measured in the first month of dialysis were haematocrit, urea, creatinine, lipids, calcium, phosphorus, parathyroid hormone and albumin.

RESULTS

Of 449 patients included in the study (age 64.4 ± 16 years), 30 commenced dialysis having had previous stroke (prevalence 6.7%). In a follow-up of 38.77 ± 29 months, 34 patients presented with one or more strokes; an incidence of 2.41/100 patient-years. Greater age [odds ratio (OR): 1.05; 95% confidence interval (CI): 1.01-1.09; P = 0.007], diabetes (OR: 2.29; 95% CI: 1.15-4.55; P = 0.018) and presence of atrial fibrillation (OR: 3.11; 95% CI: 1.53-6.32; P = 0.002) were independent predictors of stroke occurrence. Conclusions. The prevalence of ischaemic stroke is high at the commencement of dialysis, and its incidence is elevated in the course of follow-up. As with the general population, atrial fibrillation is an important factor predictive of ischaemic stroke, and as such, the clinical implication is that prophylactic anti-coagulation therapy needs to be considered for these individuals.

Atrial fibrillation in end-stage renal disease

End-stage renal disease (ESRD) is associated with increased cardiovascular morbidity and mortality. Recent studies indicate that atrial fibrillation (AF) is prevalent among ESRD patients while it adversely affects the clinical outcome. Despite these considerations, AF management in this population is problematic. Notably, most ESRD patients with AF are deprived of the benefits of anticoagulation therapy because of the fear of hemorrhagic complications. This article provides a concise and critical overview of the complex pathophysiology, epidemiology, and discusses the clinical issues regarding the emerging association between ESRD and AF.