Incident atrial fibrillation and risk of death in adults with chronic kidney disease

Comorbidity and Medication Trends in Chronic Kidney Disease and Incident Atrial Fibrillation: A Nationwide Cohort Study

INTRODUCTION

Chronic kidney disease (CKD) is associated with an increased incidence of atrial fibrillation (AF). Also, patients with AF are prone to adverse kidney outcomes. We examined comorbidities and medication use in patients with CKD and incident AF.

METHODS

The Finnish AntiCoagulation in Atrial Fibrillation (FinACAF) is a nationwide retrospective register-linkage study including data from 168,233 patients with incident AF from 2007 to 2018, with laboratory data from 2010 onwards. Estimated glomerular filtration rate (eGFR) was available for 124,936 patients. The cohort was divided into 5 CKD stages with separate groups for dialysis and kidney transplantation.

RESULTS

At AF diagnosis eGFR <60 mL/min/1.73 m2 was found in 27%, while 318 (0.3%) patients were on dialysis, and 188 (0.2%) had a functioning kidney transplant. Lowering eGFR yielded more comorbidities and medications. During 2010-2018 in patients with eGFR <60 mL/min/1.73 m2 prevalence of hypertension, dyslipidaemia, and diabetes increased from 82 to 88%, from 50 to 66% and from 25 to 33%, respectively (<0.001). Throughout the observation period, lipid-lowering medication was underused.

CONCLUSION

More than one-fourth of patients with incident AF also had CKD stage 3-5 (eGFR <60 mL/min/1.73 m2). Both comorbidities and medication use increased with worsening kidney function. Prevalence of major cardiovascular (CV) risk factors increased during 2010-2018, but the use of survival-affecting medications, such as lipid-lowering medication, was suboptimal at all stages of CKD. More attention should be given to the optimal treatment of risk factors in this high CV risk population.

Estimated glomerular filtration rate and the risk of stroke in individuals with diabetes mellitus and atrial fibrillation insight from a large contemporary population study

BACKGROUND

Diabetes mellitus (DM) is associated with increased risk of embolic complications in non-valvular atrial fibrillation (NVAF). Impaired renal function (IRF) increases the risk of stroke as well, but this finding is not consistent among all studies. Our aim was to assess the incidence rates and risk of ischemic stroke and mortality by baseline Estimated Glomerular Filtration Rate (eGFR) levels Among individuals with AF and DM.

METHODS

A prospective, historical cohort study using the Clalit Health Services electronic medical records database. Among patients with AF and DM, we compared three groups according to eGFR levels: eGFR ≥ 60, between 30 and 60, and ≤ 30 (mL/min/1.73m2).

RESULTS

A total of 17,567 cases were included in the final analysis; of them, 11,013 (62.7%) had eGFR ≥ 60, 4930 (28%) had eGFR between 30 and 60, and 1624 (9.24%) with eGFR ≤ 30. The incidence of stroke per 100 person-years in the three study groups was: 1.88, 2.69, and 3.34, respectively (p < 0.001). IRF was associated with increased risk of stroke in univariate analysis, but not after multivariate adjustment (Adjusted Hazard Ratio (AHR) 0.96 {95%CI; 0.74-1.25} for eGFR 30-60 and 0.96 {95%CI; 0.60-1.55} for eGFR ≤ 30). Mortality per 100 person-years was 10.78, 21.49, and 41.55, respectively (p < 0.001). IRF was associated with increased mortality risk in univariate analysis, as well as in multivariate analysis (AHR 1.08 {95%CI; 0.98-1.18} for eGFR 30-60, and 1.59 {95%CI; 1.37-1.85} for eGFR ≤ 30.

CONCLUSION

In patients with NVAF and DM, IRF was not associated with an increased risk of stroke, but severe IRF (eGFR ≤ 30) was associated with increased mortality risk.

Safety and Effectiveness of Rivaroxaban Versus Warfarin Across GFR Levels in Atrial Fibrillation: A Population-Based Study in Australia and Canada

Rationale & Objective

The benefit-risk profile of rivaroxaban versus warfarin for atrial fibrillation (AF) in patients with chronic kidney disease is uncertain. We compared rivaroxaban with warfarin across the range of kidney function in adults with AF.

Study Design

Multicenter retrospective cohort.

Setting & Participants

Adults with AF and a measure of estimated glomerular filtration rate (eGFR); using administrative data from 5 jurisdictions across Australia and Canada (2011-2018). Kidney function was categorized as eGFR ≥60, 45-59, 30-44, and <30 mL/min/1.73 m². Patients receiving dialysis and kidney transplant recipients were excluded.

Exposures

New dispensation of either rivaroxaban or warfarin.

Outcomes

Composite (1) effectiveness outcome (all-cause death, ischemic stroke, or transient ischemic attack) and (2) major bleeding events (intracranial, gastrointestinal, or other) at 1 year.

Analytical Approach

Cox proportional hazards models accounting for propensity score matching were performed independently in each jurisdiction and then pooled using random-effects meta-analysis.

Results

55,568 patients (27,784 rivaroxaban-warfarin user matched pairs; mean age 74 years, 46% female, 33.5% with eGFR <60 mL/min/1.73 m²) experienced a total of 4,733 (8.5%) effectiveness and 1,144 (2.0%) bleeding events. Compared to warfarin, rivaroxaban was associated with greater or similar effectiveness across a broad range of kidney function (pooled HRs of 0.72 [95% CI, 0.66-0.78], 0.78 [95% CI, 0.58-1.06], 0.70 [95% CI, 0.57-0.87], and 0.78 [95% CI, 0.62-0.99]) for eGFR ≥60, 45-59, 30-44, and <30 mL/min/1.73 m², respectively). Rivaroxaban was also associated with similar risk of major bleeding across all eGFR categories (pooled HRs of 0.75 [95% CI, 0.56-1.00], 1.01 [95% CI, 0.79-1.30], 0.87 [95% CI, 0.66-1.15], and 0.63 [95% CI, 0.37-1.09], respectively).

Limitations

Unmeasured treatment selection bias and residual confounding.

Conclusions

In adults with AF, rivaroxaban compared with warfarin was associated with lower or similar risk of all-cause death, ischemic stroke and transient ischemic attack and similar risk of bleeding across a broad range of kidney function.

Plain-Language Summary

This real-world study involved a large cohort of 55,568 adults with atrial fibrillation from 5 jurisdictions across Australia and Canada. It showed that the favorable safety (bleeding) and effectiveness (stroke or death) profile of rivaroxaban compared with warfarin was consistent across different levels of kidney function. This study adds important safety data on the use of rivaroxaban in patients with reduced kidney function, including those with estimated glomerular filtration rate <30 mL/min/1.73 m² in whom the risks and benefits of rivaroxaban use is most uncertain. Overall, the study supports the use of rivaroxaban as a safe and effective alternative to warfarin for atrial fibrillation across differing levels of kidney function.

Association of Kidney Function With Risk of Adverse Effects of Therapies for Atrial Fibrillation

Introduction

Atrial fibrillation (AF) is common in chronic kidney disease (CKD) and is treated with rate control medications, antiarrhythmic medications, as well as anticoagulation and procedures, each of which have associated risks. We aimed to evaluate the association of CKD status with the risks of adverse effects after initiation of AF therapies.

Methods

This was a cohort study of community-based adults who newly initiated rate control medications, antiarrhythmic medications, warfarin, direct oral anticoagulants (DOACs) or received AF procedures in the 1 year after diagnosis of AF. Baseline estimated glomerular filtration rate (eGFR) was calculated using outpatient serum creatinine measures. Adverse effects within 1 year related to each AF therapy or within 1 month of an AF procedure were ascertained from vital sign databases, electrocardiograms (ECGs), and administrative codes. Fine-Gray hazard models were used to study the association of eGFR categories with risk of adverse effects for each AF therapy.

Results

Among 115,564 patients with incident AF, lower eGFR (vs. eGFR ≥60 ml/min per 1.73 m²) was significantly associated with higher adjusted risk of adverse effects after initiation of rate control therapies (most commonly hypotension and bradycardia) as follows: eGFR 45-59 (hazard ratio [HR] 1.14, 95% confidence interval [CI] 1.07-1.22), 30-44 (HR 1.15, 95% CI 1.06-1.25), and 15-29 (HR 1.29, 95% CI: 1.12-1.47) ml/min per 1.73 m². Lower eGFR was associated with higher adjusted risk of adverse effects (most commonly prolonged QRS and QTc intervals) after initiation of an antiarrhythmic medication (vs. eGFR >60 ml/min per 1.73 m²) as follows: eGFR 45-59 (HR 1.12, 95% CI 1.01-1.23) and eGFR<15 (HR 1.43, 95% CI 1.01-2.01) ml/min per 1.73 m².

Conclusion

There was a graded association between lower eGFR and risk of major bleeding with warfarin use, with the greatest risk among those with eGFR <15 ml/min per 1.73 m² (HR of 2.93, 95% CI 1.99-4.30). There was no association of eGFR with major bleeding in patients receiving DOACs. Rates of adverse effects within 1 month of an AF procedure were low among patients with (n = 18) and without (n = 41) CKD and was underpowered for further analyses. In conclusion, lower eGFR was associated with significantly higher risks of adverse effects after initiation of commonly used therapies to treat AF. These data may help inform the complex therapeutic decisions in patients with CKD and AF.

Management of Adults with Newly Diagnosed Atrial Fibrillation with and without CKD

BACKGROUND

Atrial fibrillation (AF) is highly prevalent in CKD and is associated with worse cardiovascular and kidney outcomes. Limited data exist on use of AF pharmacotherapies and AF-related procedures by CKD status. We examined a large "real-world" contemporary population with incident AF to study the association of CKD with management of AF.

METHODS

We identified patients with newly diagnosed AF between 2010 and 2017 from two large, integrated health care delivery systems. eGFR (≥60, 45-59, 30-44, 15-29, <15 ml/min per 1.73 m²) was calculated from a minimum of two ambulatory serum creatinine measures separated by ≥90 days. AF medications and procedures were identified from electronic health records. We performed multivariable Fine-Gray subdistribution hazards regression to test the association of CKD severity with receipt of targeted AF therapies.

RESULTS

Among 115,564 patients with incident AF, 34% had baseline CKD. In multivariable models, compared with those with eGFR >60 ml/min per 1.73 m², patients with eGFR 30-44 (adjusted hazard ratio [aHR] 0.91; 95% CI, 0.99 to 0.93), 15-29 (aHR, 0.78; 95% CI, 0.75 to 0.82), and <15 ml/min per 1.73 m² (aHR, 0.64; 95% CI, 0.58-0.70) had lower use of any AF therapy. Patients with eGFR 15-29 ml/min per 1.73 m² had lower adjusted use of rate control agents (aHR, 0.61; 95% CI, 0.56 to 0.67), warfarin (aHR, 0.89; 95% CI, 0.84 to 0.94), and DOACs (aHR, 0.23; 95% CI, 0.19 to 0.27) compared with patients with eGFR >60 ml/min per 1.73 m². These associations were even stronger for eGFR <15 ml/min per 1.73 m². There was also a graded association between CKD severity and receipt of AF-related procedures (vs eGFR >60 ml/min per 1.73 m²): eGFR 30-44 ml/min per 1.73 (aHR, 0.78; 95% CI, 0.70 to 0.87), eGFR 15-29 ml/min per 1.73 m² (aHR, 0.73; 95% CI, 0.61 to 0.88), and eGFR <15 ml/min per 1.73 m² (aHR, 0.48; 95% CI, 0.31 to 0.74).

CONCLUSIONS

In adults with newly diagnosed AF, CKD severity was associated with lower receipt of rate control agents, anticoagulation, and AF procedures. Additional data on efficacy and safety of AF therapies in CKD populations are needed to inform management strategies.

Renal Function Protection as an Important Component of a Comprehensive Approach to the Management of Patients with Atrial Fibrillation

The increase in the life expectancy of the population  is accompanied by an increase in the prevalence of diseases for which old and senile age are risk factors. Atrial fibrillation (AF) and chronic kidney disease (CKD) are two diseases that can coexist in a patient. The risk of ac thromboembolic and hemorrhagic events in this case increases due to the mutual aggravating influence of these diseases. In addition,  these patients have a high incidence of coronary  events, and cardiovascular complications are the main cause of death in patients with AF and CKD. Consequently, such patients require an integrated  approach  to treatment,  and their management is a complex  clinical task. The direct oral anticoagulant rivaroxaban has been most studied in a population  of comorbid  AF and CKD  patients and has proven a high efficacy and safety profile in these patients in randomized controlled trials. In addition,  rivaroxaban has shown  a significant  reduction in the risk of myocardial  infarction  in various patients,  as well as the possibility of preserving renal function to a greater extent compared  with warfarin therapy, and a possible positive effect on reducing  the risk of cognitive impairment.  A single dosing  regimen  can improve adherence  to treatment,  which is one of the key conditions  for achieving  the above effects. Thus, these factors make it possible to achieve comprehensive protection of comorbid  patients with AF and CKD.

Revisiting risk prediction tools for death and end-stage renal disease in older patients with advanced chronic kidney disease: a prospective study

BACKGROUND

Risk assessment tools for predicting mortality and end-stage renal disease (ESRD) in the elderly with CKD have received growing attention. However, integrating risk equations into a multidimensional approach of elderly with CKD stage 3b-4 is lacking.

METHODS

In this prospective observational study, we enrolled CKD stage 3b-4 patients aged ≥ 65 years. Bansal score for predicting mortality risk and Kidney Failure Risk Equation (KFRE) for estimating progression to ESRD were applied. Predicted outcome was compared with actual clinical end-points. All patients underwent comprehensive geriatric assessment (CGA), which is an interdisciplinary multidimensional process for geriatric evaluation and management.

RESULTS

Participants (N = 184) were divided into two groups, according to Bansal score: Group 1 (low-risk of death, Bansal score < 7, N = 69) and Group 2 (high-risk of death, Bansal score ≥ 7, N = 115). Group 2 displayed a substantially higher cardiovascular disease burden than Group 1 and was significantly more likely to be depressed and at risk of malnutrition, according to CGA. Thirty-seven patients died, and 16 started dialysis. Group 2 displayed significantly higher all-cause mortality. In the univariable Cox regression, Group 2 had a fourfold increase in the risk of all-cause mortality, as compared with Group 1 (HR = 4.29, 95% CI 1.88-10.26, P < 0.001). Multivariable stepwise Cox analysis showed that Bansal score above 7 remained significantly associated with all-cause mortality (HR = 3.96, 95% CI 1.68-9.29, P < 0.001). Group 2 also displayed higher event rates for dialysis initiation. In Group 1, only four patients started dialysis, and three out of them had a high-risk of progression at baseline, according to KFRE.

CONCLUSIONS

Using risk stratification tools and CGA in a population of elderly with advanced CKD, we found that two-thirds of the patients were at high risk of death, malnutrition and depression, with multimorbidity and four times worse probability of survival than those at lower risk of death.

Prediction of Recurrent Atrial Tachyarrhythmia After Receiving Atrial Flutter Ablation in Patients With Prior Cardiac Surgery for Valvular Heart Disease

Background: Surgical scars cause an intra-atrial conduction delay and anatomical obstacles that facilitate the perpetuation of atrial flutter (AFL). This study aimed to investigate the outcome and predictor of recurrent atrial tachyarrhythmia after catheter ablation in patients with prior cardiac surgery for valvular heart disease (VHD) who presented with AFL.

Methods: Seventy-two patients with prior cardiac surgery for VHD who underwent AFL ablation were included. The patients were categorized into a typical AFL group (n = 45) and an atypical AFL group (n = 27). The endpoint was the recurrence of atrial tachyarrhythmia during follow-up. A multivariate analysis was performed to determine the predictor of recurrence.

Results: No significant difference was found in the recurrence rate of atrial tachyarrhythmia between the two groups. Patients with concomitant atrial fibrillation (AF) had a higher recurrence of typical AFL compared with those without AF (13 vs. 0%, P = 0.012). In subgroup analysis, typical AFL patients with concomitant AF had a higher incidence of recurrent atrial tachyarrhythmia than those without it (53 vs. 14%, P = 0.006). Regarding patients without AF, the typical AFL group had a lower recurrence rate of atrial tachyarrhythmia than the atypical AFL group (14 vs. 40%, P = 0.043). Multivariate analysis showed that chronic kidney disease (CKD) and left atrial diameter (LAD) were independent predictors of recurrence.

Conclusions: In our study cohort, concomitant AF was associated with recurrence of atrial tachyarrhythmia. CKD and LAD independently predicted recurrence after AFL ablation in patients who have undergone cardiac surgery for VHD.

Prediction of Incident Atrial Fibrillation in Chronic Kidney Disease: The Chronic Renal Insufficiency Cohort Study

BACKGROUND AND OBJECTIVES

Atrial fibrillation (AF) is common in CKD and associated with poor kidney and cardiovascular outcomes. Prediction models developed using novel methods may be useful to identify patients with CKD at highest risk of incident AF. We compared a previously published prediction model with models developed using machine learning methods in a CKD population.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We studied 2766 participants in the Chronic Renal Insufficiency Cohort study without prior AF with complete cardiac biomarker (N-terminal pro-B-type natriuretic peptide and high-sensitivity troponin T) and clinical data. We evaluated the utility of machine learning methods as well as a previously validated clinical prediction model (Cohorts for Heart and Aging Research in Genomic Epidemiology [CHARGE]-AF, which included 11 predictors, using original and re-estimated coefficients) to predict incident AF. Discriminatory ability of each model was assessed using the ten-fold cross-validated C-index; calibration was evaluated graphically and with the Grønnesby and Borgan test.

RESULTS

Mean (SD) age of participants was 57 (11) years, 55% were men, 38% were Black, and mean (SD) eGFR was 45 (15) ml/min per 1.73 m2; 259 incident AF events occurred during a median of 8 years of follow-up. The CHARGE-AF prediction equation using original and re-estimated coefficients had C-indices of 0.67 (95% confidence interval, 0.64 to 0.71) and 0.67 (95% confidence interval, 0.64 to 0.70), respectively. A likelihood-based boosting model using clinical variables only had a C-index of 0.67 (95% confidence interval, 0.64 to 0.70); adding N-terminal pro-B-type natriuretic peptide, high-sensitivity troponin T, or both biomarkers improved the C-index by 0.04, 0.01, and 0.04, respectively. In addition to N-terminal pro-B-type natriuretic peptide and high-sensitivity troponin T, the final model included age, non-Hispanic Black race/ethnicity, Hispanic race/ethnicity, cardiovascular disease, chronic obstructive pulmonary disease, myocardial infarction, peripheral vascular disease, use of angiotensin-converting enzyme inhibitor/angiotensin receptor blockers, calcium channel blockers, diuretics, height, and weight.

CONCLUSIONS

Using machine learning algorithms, a model that included 12 standard clinical variables and cardiac-specific biomarkers N-terminal pro-B-type natriuretic peptide and high-sensitivity troponin T had moderate discrimination for incident AF in a CKD population.

Fibroblast growth factor 23 (FGF23) induces ventricular arrhythmias and prolongs QTc interval in mice in an FGF receptor 4-dependent manner

Fibroblast growth factor 23 (FGF23) is a phosphate regulating protein hormone released by osteocytes. FGF23 becomes markedly elevated in chronic kidney disease (CKD), for which the leading cause of death is cardiovascular disease, particularly sudden cardiac death. Previously, we found that FGF23 increases intracellular Ca²⁺ in cardiomyocytes and alters contractility in mouse ventricles ex vivo via FGF receptor 4 (FGFR4). In the present study, we demonstrate that FGF23 induces cardiac arrhythmias and prolongs QTc interval in mice, and we tested whether these effects are mediated through FGFR4. In isolated Langendorff perfused hearts, FGF23 perfusion increased mechanical arrhythmias in the form of premature ventricular beats (PVBs), and induced runs of ventricular tachycardia in 6 of 11 animals, which were attenuated with pretreatment of an anti-FGFR4 blocking antibody. Ex vivo ECG analysis of isolated intact hearts showed increased ventricular arrhythmias and QTc prolongation after FGF23 infusion compared with vehicle. In vivo, injection of FGF23 into the jugular vein led to the emergence of premature ventricular contractions (PVCs) in 5 out of 11 experiments. FGF23 also produced a significant lengthening effect upon QTc interval in vivo. In vivo FGFR4 blockade ameliorated the arrhythmogenic and QTc prolonging effects of FGF23. Finally, FGF23 increased cardiomyocyte Ca²⁺ levels in intact left ventricular muscle which was inhibited by FGR4 blockade. We conclude that FGF23/FGFR4 signaling in the heart may contribute to ventricular arrhythmogenesis and repolarization disturbances commonly observed in patients with CKD via Ca²⁺ overload and may be an important therapeutic target to reduce cardiac mortality in CKD.NEW & NOTEWORTHY Here we provide direct evidence that fibroblast growth factor 23 (FGF23), a phosphaturic hormone elevated in chronic kidney disease, is proarrhythmic. FGF23 acutely triggered ventricular arrhythmias and prolonged corrected QT interval (QTc) in isolated mouse hearts and in vivo. FGF23 also increased Ca²⁺ levels in ventricular muscle tissue. Blockade of the FGF receptor 4 signaling pathway using a monoclonal antibody ameliorated ventricular arrhythmias, QTc prolongation, and elevated ventricular Ca²⁺ induced by FGF23, and may represent a potential therapeutic target in chronic kidney disease.

Risk Factors for CKD Progression: Overview of Findings from the CRIC Study

The Chronic Renal Insufficiency Cohort (CRIC) Study is an ongoing, multicenter, longitudinal study of nearly 5500 adults with CKD in the United States. Over the past 10 years, the CRIC Study has made significant contributions to the understanding of factors associated with CKD progression. This review summarizes findings from longitudinal studies evaluating risk factors associated with CKD progression in the CRIC Study, grouped into the following six thematic categories: (1) sociodemographic and economic (sex, race/ethnicity, and nephrology care); (2) behavioral (healthy lifestyle, diet, and sleep); (3) genetic (apoL1, genome-wide association study, and renin-angiotensin-aldosterone system pathway genes); (4) cardiovascular (atrial fibrillation, hypertension, and vascular stiffness); (5) metabolic (fibroblast growth factor 23 and urinary oxalate); and (6) novel factors (AKI and biomarkers of kidney injury). Additionally, we highlight areas where future research is needed, and opportunities for interdisciplinary collaboration.

Chronic Kidney Disease Progression and Transition Probabilities in a Large Preventive Cohort in Colombia

BACKGROUND

Variability in chronic kidney disease (CKD) progression is a well-known phenomenon that underlines the importance of characterizing the said outcome in specific populations. Our objectives were to evaluate changes in the estimated glomerular filtration rate (eGFR) over time and determine the frequency of dialysis admission and factors associated with this outcome, to estimate the rate of program's loss-to-follow-up and the probability of transition between CKD stages over time.

METHODS

The study type was an observational analytic retrospective cohort in patients treated in a CKD prevention program in Bogota, Colombia, between January 1, 2009, and December 31, 2013, with follow-up until December 31, 2018. Adult participants of 18 years of age or older with diagnosed CKD stages G3 or G4 were enrolled into a prevention program. For each patient, the rate of progression of CKD in ml/min/1.73 m2/year was estimated using the ordinary least-squares method. Dialysis initiation and program's loss-to-follow-up rates were calculated. Heat maps were used to present probabilities of transitioning between various CKD stages over time. Survival model with competing risks was used to evaluate factors associated with dialysis initiation.

RESULTS

A total of 2752 patients met inclusion criteria and contributed with 14133 patient-years of follow-up and 200 dialysis initiation events, which represents a rate of 1.4 events per 100 patient-years (95% CI 1.2 to 1.6). The median change of the eGFR for the entire cohort was -0.47 ml/min/1.73 m2 per year, and in the diabetic population, it was -1.55 ml/min/1.73 m2 per year. The program's loss-to-follow-up rate was 2.6 events per 100 patient-years (95% CI 2.3 to 2.9). Probabilities of CKD stage transitions are presented in heat maps. Female sex, older age, baseline eGFR, and serum albumin were associated with lower risk of dialysis initiation while CKD etiology diabetes, cardiovascular disease history, systolic blood pressure, blood urea nitrogen, and LDL cholesterol were associated with a higher likelihood of dialysis initiation.

CONCLUSIONS

A CKD secondary prevention program's key indicator is reported here, such as dialysis initiation, progression rate, and program drop-out; CKD progression appears to be correlated with diabetic status and timing of referral into the preventive program.

Direct Oral Anticoagulants in Patients with Atrial Fibrillation and Renal Dysfunction

Atrial fibrillation and renal dysfunction often coexist, each disorder may predispose to the other and contribute to worsening prognosis. Both atrial fibrillation and chronic kidney disease are associated with increased risk of stroke and thromboembolic complications. Oral anticoagulation for stroke prevention is therefore recommended in patients with atrial fibrillation and decreased renal function. Each direct oral anticoagulant has unique pharmacologic properties of which clinician should be aware to optimally manage patients. The doses of direct oral anticoagulants require adjustment for renal function. There is debate regarding which equation, the Chronic Kidney Disease Epidemiology (CKD-EPI) equation vs. the Cockcroft-Gault equation, should be used to estimate glomerular filtration rate in patients with atrial fibrillation treated with direct oral anticoagulants. Our review tries to find arguments for benefit of direct oral anticoagulants in patients with renal dysfunction.

Asymptomatic Supraventricular Arrhythmias in Patients Undergoing Dialysis

Aim. Supraventricular arrhythmias (SVA) are associated with high morbidity and mortality. However, little attention is paid to this condition in patients undergoing hemodialysis. The aim of this study was to analyze the long-term relationship of intradialytic SVA, including asymptomatic arrhythmias, with adverse events in a cohort of patients undergoing hemodialysis.

Material and methods. An observational prospective study was conducted in a group of patients on hemodialysis with a 10-year follow-up. The study involved 77 patients (42 men and 35 women; mean age 58±15 years) with sinus rhythm, then they were monitored for ECG for six consecutive hemodialysis sessions during recruitment.

Results. Arterial hypertension was present in 68.8% of patients, diabetes mellitus in 29.9% of patients. SVA were reported in 38 patients (49.3%); they all had a short-term, asymptomatic character and were terminated independently. Age (hazard ratio [HR] 1.04 per year; 95% confidence interval [CI] 1.00-1.08) and an increase of the atrium (HR 4.29; 95%CI 1.30-14.09) were associated with supraventricular arrhythmia in multidimensional analysis. During an average follow-up of 40 months, 57 patients died, and cardiovascular diseases were the main cause of death (52.6%). Variables associated with all-cause mortality in the Cox model were age (HR 1.04 per year; 95%CI 1.00-1.08), C-reactive protein (HR 1.04 per 1 mg/l; 95%CI 1.00-1.08) and supraventricular arrhythmias (HR 3.21; 95%CI 1.29-7.96). Patients with supraventricular arrhythmias also had a higher risk of nonfatal cardiovascular events (HR 4.32; 95%CI 2.11-8.83) and symptomatic atrial fibrillation during observation (HR 17.19; 95%CI 2.03-145.15).

Conclusions. Strong relationships have been established between the presence of supraventricular arrhythmias recorded during ECG during dialysis and symptomatic AF developing in the future. Patients with supraventricular arrhythmias had a larger right atrium. Age and supraventricular arrhythmias are the main variables associated with mortality in dialysis patients.

Oral anticoagulation in chronic kidney disease with atrial fibrillation

Chronic kidney disease (CKD) and atrial fibrillation (AF) frequently coexist, amplifying the risk of cardiovascular events and mortality. In patients with CKD stage 3 and non-valvular AF, direct oral anticoagulants (DOACs) have shown, compared to vitamin K antagonists (VKA), equal or greater efficacy in the prevention of stroke and systemic embolism, and greater safety. There are no randomizedtrials of the efficacy and safety of DOACs and VKA in advanced CKD. On the other hand, observational studies suggest that DOACs, compared to warfarin, are associated with a lower risk of acute kidney damage and generation/progression of CKD. This paper reviews the epidemiological and pathophysiological aspects of the CKD and AF association, the evidence of the efficacy and safety of warfarin and ACODs in various stages of CKD with AF as well as the comparison between warfarin and ACODs in efficacy and anticoagulant safety, and in its renal effects.

The Impact of Body Weight and Renal Function on the Risk of Bleeding With Direct Oral Anticoagulants in Atrial Fibrillation

BACKGROUND

Atrial fibrillation (AF) increases the risk of stroke and direct oral anticoagulants (DOACs) are first-line agents for prevention. Gaps in the literature cause reluctance in prescribing DOACs for patients with renal dysfunction and/or extremes in body weight.

OBJECTIVE

To evaluate the impact body weight and renal function have on major and clinically relevant nonmajor (CRNM) bleeding events and ischemic strokes in AF patients receiving a DOAC.

METHODS

This retrospective cohort study included adults with nonvalvular atrial fibrillation (NVAF) or atrial flutter (AFL) receiving a DOAC ≥12 months. The primary outcome was a composite of major and CRNM bleeding events. Secondary outcomes included ischemic stroke and risk factors for bleeding events.

RESULTS

Of the 233 patients analyzed, 25 patients experienced a bleeding event. Patients who bled weighed 10 kg less (P = 0.043) than those who did not and had a higher HASBLED score (P = 0.003). Multivariate logistic regression identified weight (P = 0.048), serum creatinine (SCr; P = 0.027), and HASBLED score (P = 0.024) as the significant predictors for experiencing a bleed. Three patients experienced a stroke.

CONCLUSION AND RELEVANCE

This study demonstrates an association between higher baseline SCr, elevated HASBLED score, and lower weight, with an increased risk of bleeding in patients with NVAF or AFL receiving a DOAC. These findings add to prescribing considerations when initiating DOACs. Closer monitoring is advised for patients with significant renal dysfunction and/or low body weight, even with renal dose adjustments.

Chronic kidney disease and cardiovascular mortality in patients with atrial fibrillation: European Society of Hypertension project - ESH A Fib

Our aim was to analyze characteristics of atrial fibrillation (AF) patients with chronic kidney disease (CKD) from the Croatian cohort of the ESH A Fib survey and to determine the association of estimated glomerular filtration rate (eGFR) with cardiovascular (CV) mortality after 24 months of follow-up.Consecutive sample of 301 patients with AF were enrolled in the period 2014 to 2018. Hypertension was defined as BP > 140/90 mm Hg and/or antihypertensive drugs treatment, CKD was defined as eGFR (CKD Epi) < 60 ml/min/1.73 m2 which was confirmed after 3 months.CKD was diagnosed in 45.2% of patients (13.3% in CKD stage > 3b). CKD patients were older than non-CKD and had significantly more frequent coronary heart disease, heart failure and valvular disease. CKD patients had significantly higher CHA2DS2-VASc score and more CKD than non-CKD patients had CHA2DS2-VASc > 2. Crude CV mortality rate per 1000 population at the end of the first year of the follow-up was significantly higher in CKD vs non-CKD group who had shorter mean survival time. CV mortality was independently associated with eGFR, male gender, CHA2DS2VASc and R2CHA2DS2VASc scores.Prevalence of CKD, particularly more advanced stages of CKD, is very high in patients with AF. Observed higher CV mortality and shorter mean survival time in CKD patients could be explained with higher CHA2DS2VASc score which is a consequence of clustering of all score components in CKD patients. However, eGFR was independently associated with CV mortality. In our cohort, R2CHA2DS2VASc score was not associated significantly more with CV mortality than CHA2DS2VASc score.

An Elderly Comorbid Patient with Atrial Fibrillation: What is Important to Know and What Should be Considered When Prescribing Anticoagulants?

Anticoagulant therapy in elderly patients with atrial fibrillation and concomitant diseases is often the challenge for clinicians. The high risk of stroke is inherent in atrial fibrillation, and it increases when combined with coronary heart disease and chronic kidney disease. On the other hand, the comorbidity increases the risk of bleeding. Older age is also the risk factor of thrombotic and hemorrhagic complications. As a consequence, the choice of specific anticoagulant should be based on a solid evidences, obtained both from randomized clinical trials and from daily clinical practice. In the ROCKET AF trail the direct oral anticoagulant rivaroxaban showed a tendency to reduce the risk of thromboembolism by 20% compared with warfarin in the patients aged 75 years and older. The safety of rivaroxaban has been evaluated in the XANTUS POOLED program. According to the follow-up results for 12 months, more than 96% of patients didn't have any adverse event, and the number of patients with major bleeding was 1.5%. Several meta-analyzes reported a reduction of cardiovascular complications in patients treated by rivaroxaban. In the ROCKET AF trail, a “renal” dose of rivaroxaban (15 mg OD) was studied in patients with chronic kidney disease. The efficacy and safety of rivaroxaban were validated in this patients, and a simple algorithm for selecting the dose of this drug in patients with chronic kidney disease was provided.

 

Incidence and Implications of Atrial Fibrillation/Flutter in Hypertension: Insights From the SPRINT Trial

We evaluated the impact of intensive blood pressure control on the incidence of new-onset atrial fibrillation/flutter (AF) and the prognostic implications of preexisting and new-onset AF in SPRINT (Systolic Blood Pressure Intervention Trial) participants. New-onset AF was defined as occurrence of AF in 12-lead electrocardiograms after randomization in participants free of AF at baseline. Poisson regression modeling was used to calculate incident rates of new-onset AF. Multivariable-adjusted Cox proportional hazard models were used to evaluate the risk of adverse cardiovascular events (composite of myocardial infarction, non-myocardial infarction acute coronary syndrome, stroke, heart failure, or cardiovascular death). In 9327 participants, 8.45% had preexisting AF, and 1.65% had new-onset AF. The incidence of new-onset AF was 4.53 per 1000-person years, with similar rates in the standard and intensive treatment arms (4.95 versus 4.11 per 1000-person years; adjusted P=0.14). Participants with preexisting AF (adjusted hazard ratio, 1.83 [95% CI, 1.46-2.31]; P<0.001) and new-onset AF (adjusted hazard ratio, 2.45 [95% CI, 1.58-3.80]; P<0.001) had a greater risk for development of adverse cardiovascular events compared with those with no AF. Participants with preexisting AF who achieved blood pressure <120/80 mm Hg at 3 months continued have a poor prognosis (adjusted hazard ratio, 1.88 [95% CI, 1.32-2.70]; P=0.001) compared with those with no AF. Intensive blood pressure control does not diminish the incidence of new-onset AF in an older, high-risk, nondiabetic population. Both preexisting and new-onset AF have adverse prognostic implications. In participants with preexisting AF, residual cardiovascular risk is evident even with on-treatment blood pressure <120/80 mm Hg. Registration- URL: https://www.clinicaltrials.gov; Unique identifier: NCT01206062.

Systematic DOACs oral anticoagulation in patients with atrial fibrillation and chronic kidney disease: the nephrologist's perspective

Atrial fibrillation (AF) is highly prevalent among patients with chronic kidney disease (CKD), and also associated with unfavorable outcome. Anticoagulant therapy is the mainstep of management in such patients, aimed at reducing the high risk of systemic thromboembolism and especially of ischemic stroke, which is reportedly associated with increased mortality in CKD patients. Even though new direct oral anticoagulant agents (DOACs) proved to be effective in patients with non valvular chronic AF, and are therefore recommended by recent guidelines for their treatment, warfarin is currently used in more than one-half of subjects needing oral anticoagulation, and only 30% of them are converted from a vitamin K antagonist- to a DOAC-based regimen. The main reason for not prescribing DOACs is often a reduction in renal function, even if mild. Aim of this review was therefore to evaluate the impact of DOAC therapy in the setting of CKD, from a nephrological perspective, by comparing available evidence on the role of DOACs in patients with CKD and AF with that emerging from traditional warfarin-based therapy. Both the pathogenesis of AF in CKD, and available findings of renal, cardiovascular and bone effects of DOACs in CKD are discussed, leading to the conclusion that DOAC therapy should be considered as the first line therapy for non valvular AF in patients with mild and moderate reduction of renal function, and could also be adopted for patients with severe CKD not on hemodialysis treatment, whereas there is insufficient evidence for ESRD patients on dialysis.

Factors Associated with a Large Decline in Renal Function or Progression to Renal Insufficiency in Hospitalized Atrial Fibrillation Patients with Early-Stage CKD

Clinicians must consider renal function when administering anticoagulants for atrial fibrillation (AF). Determination of risk factors for renal function decline may enable identification of patients who require closer monitoring. We investigated the characteristics associated with renal function decline in patients with AF. The study cohort consisted of 631 AF patients who had at least one readmission during the follow-up period and stages 1-3 chronic kidney disease (CKD). The primary outcome measure was large renal function decline (≥30% decrease from baseline estimated glomerular filtration rate [eGFR]). The secondary outcome measure was a final eGFR < 60 mL/minute/1.73 m² for those with a baseline eGFR above this level. The mean eGFR was 74.4 ± 18.5 mL/minute/1.73 m², and the mean follow-up time was 30.2 ± 13.2 months. The primary outcome occurred in 155 patients (24.6%) and was associated with congestive heart failure (CHF), proteinuria, type of AF, and left atrial diameter (LAD) ≥ 45 mm. Among 478 patients with a baseline eGFR ≥ 60 mL/minute/1.73 m², 137 (28.7%) progressed to renal failure (eGFR < 60 mL/minute/1.73 m²). A decreasing eGFR was associated with age ≥ 75 years, CHF, lower baseline eGFR, and LAD ≥ 45 mm. CHF, proteinuria, type of AF, and LAD ≥ 45 mm were associated with eGFR decline ≥ 30% in AF patients with CKD stages 1-3. Advanced age, CHF, lower baseline eGFR, and LAD ≥ 45 mm were associated with progression to renal insufficiency. These results should be considered when identifying patients who require more frequent monitoring of eGFR.

Clinical outcomes and treatment patterns among Medicare patients with nonvalvular atrial fibrillation (NVAF) and chronic kidney disease

Background

Patients with nonvalvular atrial fibrillation (NVAF) and chronic kidney disease (CKD) have increased risk of adverse outcomes. This study evaluated treatment with oral anticoagulants and outcomes in elderly NVAF patients with CKD.

Methods

Retrospective observational cohort study of US Medicare fee-for-service patients aged ≥66 years with comorbid CKD (advanced: Stage 4 and higher; less advanced: Stages 1–3) and a new NVAF diagnoses from 2011–2013. All-cause mortality, stroke, major bleeding, and myocardial infarction rates were estimated for 1 year post-NVAF diagnosis. Associations between CKD stage and outcomes were evaluated with multivariate-adjusted Cox regression. We assessed oral anticoagulant (OAC) receipt within 90 days post-NVAF diagnosis and associations between OAC receipt and outcomes.

Results

There were 198,380 eligible patients (79,681 with advanced CKD). After adjustment for age, gender, and comorbidities, advanced CKD was associated with increased mortality (Stage 5 HR 1.47; 95% CI 1.42–1.52), MI (HR 1.48; 95% CI 1.33–1.64), stroke (HR 1.23; 95% CI 1.11–1.37) and major bleed (HR 1.44; 95% CI 1.36–1.53) risks. Among Medicare Part D enrollees who survived ≥90 days post-NVAF diagnosis, 65–71% received no OACs in the first 90 days. Those receiving warfarin (HR 0.73; 95% CI 0.71–0.75) or DOACs (HR 0.52; 95% CI 0.49–0.56) within the first 90 days had reduced mortality in the period 90 days to 1 year following NVAF diagnosis compared to those without.

Conclusion

Elderly NVAF patients with advanced CKD (Stage 4 or higher) had higher mortality risks and serious clinical outcomes than those with less advanced CKD (Stage 1–3). OAC use was low across all CKD stages, but was associated with a lower mortality risk than no OAC use in the first year post-NVAF diagnosis.

Effect of anticoagulation therapy in older patients with chronic kidney disease and atrial fibrillation: A meta-analysis

BACKGROUND

The role of anticoagulation therapy for stroke prevention in older atrial fibrillation (AF) patients with chronic kidney disease (CKD) remains unclear. Therefore, we conducted a meta-analysis to explore the efficacy and safety of anticoagulation therapy in this population.

METHODS

The Cochrane Library, PubMed, and Embase databases were systematically searched for studies reporting the effect of anticoagulation therapy in older patients with AF and CKD. The risk ratios (RRs) and 95% confidence intervals (CIs) were regarded as the risk estimates. A random-effects model selected was to evaluate the treatment outcomes. The presentations were based on the Preferred Reporting Items for reporting systematic reviews and meta-analyses statement.

RESULTS

A total of 7 studies with 24,794 older patients with AF and CKD were included. The follow-up of the included studies ranged from 0.9 to 9.0 years. In older patients with no dialysis, compared with nonanticoagulants, anticoagulants reduced the risk of all-cause death (RR 0.66, 95% CI 0.54-0.79), but had comparable risks of ischemic stroke/transient ischemic attack (TIA, RR 0.91, 95% CI 0.46-1.79) and bleeding (RR 1.17, 95% CI 0.86-1.60). In older patients with dialysis, compared with nonanticoagulants, anticoagulants increased the risk of bleeding (RR 1.37, 95% CI 1.09-1.74), but had similar risks of ischemic stroke/TIA (RR 1.18, 95% CI 0.88-1.58) and death (RR 0.87, 95% CI 0.60-1.27).

CONCLUSION

Compared with nonanticoagulation, anticoagulation therapy is associated with a reduced risk of death in older AF patients with nondialysis, but an increased risk of bleeding in older patients with dialysis.

Cognitive Function and Atrial Fibrillation: From the Strength of Relationship to the Dark Side of Prevention. Is There a Contribution from Sinus Rhythm Restoration and Maintenance?

Atrial fibrillation (AF) is the most common chronic cardiac arrhythmia with an increasing prevalence over time mainly because of population aging. It is well established that the presence of AF increases the risk of stroke, heart failure, sudden death, and cardiovascular morbidity. In the last two decades several reports have shown an association between AF and cognitive function, ranging from impairment to dementia. Ischemic stroke linked to AF is a well-known risk factor and predictor of cognitive decline. In this clinical scenario, the risk of stroke might be reduced by oral anticoagulation. However, recent data suggest that AF may be a predictor of cognitive impairment and dementia also in the absence of stroke. Cerebral hypoperfusion, reduced brain volume, microbleeds, white matter hyperintensity, neuroinflammation, and genetic factors have been considered as potential mechanisms involved in the pathogenesis of AF-related cognitive dysfunction. However, a cause-effect relationship remains still controversial. Consequently, no therapeutic strategies are available to prevent AF-related cognitive decline in stroke-free patients. This review will analyze the potential mechanisms leading to cognitive dysfunction in AF patients and examine the available data on the impact of a sinus rhythm restoration and maintenance strategy in reducing the risk of cognitive decline.

Effects of Prevalent and Incident Atrial Fibrillation on Renal Outcome, Cardiovascular Events, and Mortality in Patients with Chronic Kidney Disease

BACKGROUND

Little is known about how incident atrial fibrillation (AF) affects the clinical outcomes in chronic kidney disease (CKD) patients and whether there is a different influence between pre-existing and incident AF.

METHODS

Incident CKD patients from 2000 to 2013 were retrieved from the National Health Insurance Research Database (NHIRD) of Taiwan and they were classified as non-AF (n = 15,251), prevalent AF (n = 612), and incident AF (n = 588). The outcomes of interest were end-stage renal disease (ESRD) requiring dialysis, all-cause mortality, cardiovascular (CV) mortality, acute myocardial infarction (AMI), stroke or systemic thromboembolism.

RESULTS

Compared with CKD patients without AF, those with prevalent or incident AF were associated with higher adjusted rates of ESRD (hazard ratio (HR), 1.40; 95% confidence interval (CI), 1.32-1.48; HR, 2.91; 95% CI, 2.74-3.09, respectively), stroke or systemic thromboembolism (HR, 1.89; 95% CI, 1.77-2.03; HR, 1.67; 95% CI, 1.54-1.81, respectively), AMI (HR, 1.24; 95% CI, 1.09-1.41; HR, 1.99; 95% CI, 1.75-2.27, respectively), all-cause mortality (HR, 1.64; 95% CI, 1.56-1.72; HR, 2.17; 95% CI, 2.06-2.29, respectively), and CV mortality (HR, 2.95; 95% CI, 2.62-3.32; HR, 4.61; 95% CI, 4.09-5.20, respectively). Intriguingly, CKD patients with prevalent AF were associated with lower adjusted rates of ESRD, AMI, all-cause mortality, and CV mortality compared with those with incident AF.

CONCLUSION

Both incident and prevalent AF were independently associated with greater risks of AMI, all-cause mortality, CV mortality, ESRD, and stroke or systemic thromboembolism. Our findings are novel in that, compared with prevalent AF, incident AF possessed an even higher risk of some clinical consequences, including ESRD, all-cause mortality, CV mortality, and AMI.

High-sensitivity troponin and the risk of atrial fibrillation in chronic kidney disease: Results from the Chronic Renal Insufficiency Cohort Study

BACKGROUND

Patients with chronic kidney disease (CKD) are at an increased risk of atrial fibrillation (AF). There is a need for novel biomarkers to reliably and accurately predict AF in this population. High-sensitivity troponin (HsTP) allows the detection of low troponin concentrations. The utility of HsTP for evaluating the risk of AF in CKD has not been established.

OBJECTIVE

We sought to explore the association between HsTP and the risk of incident AF in CKD.

METHODS

The Chronic Renal Insufficiency Cohort is a prospective cohort of 3939 individuals with mild to moderate CKD. HsTP was measured at study enrollment. Patients with a history of AF were excluded. Patients were followed for new-onset AF, and the association between HsTP and incident AF was examined using the Cox regression model.

RESULTS

A total of 3217 participants were included. Over a median follow-up period of 7.1 years (interquartile range 5.0-8.4 years), 252 patients developed new-onset AF (12 events per 1000 person-years of follow-up). The incidence of new-onset AF was 2.46%, 7.06%, and 11.5% at 3, 6, and 9 years, respectively. Compared with the lowest quartile of HsTP, patients in the third quartile of HsTP (hazard ratio 2.40; 95% confidence interval 1.58-3.65; P < .001) and the fourth quartile of HsTP (hazard ratio 4.43; 95% confidence interval 2.98-6.59; P < .001) had a higher incidence of AF.

CONCLUSION

HsTP levels are associated with an increased risk of AF in patients with mild to moderate CKD. This association remains significant despite adjustment for traditional AF risk factors and chronic renal disease.

Cardiac Biomarkers and Risk of Atrial Fibrillation in Chronic Kidney Disease: The CRIC Study

Background

We tested associations of cardiac biomarkers of myocardial stretch, injury, inflammation, and fibrosis with the risk of incident atrial fibrillation (AF) in a prospective study of chronic kidney disease patients.

Methods and Results

The study sample was 3053 participants with chronic kidney disease in the multicenter CRIC (Chronic Renal Insufficiency Cohort) study who were not identified as having AF at baseline. Cardiac biomarkers, measured at baseline, were NT‐proBNP (N‐terminal pro‐B‐type natriuretic peptide), high‐sensitivity troponin T, galectin‐3, growth differentiation factor‐15, and soluble ST‐2. Incident AF (“AF event”) was defined as a hospitalization for AF. During a median follow‐up of 8 years, 279 (9%) participants developed a new AF event. In adjusted models, higher baseline log‐transformed NT‐proBNP (N‐terminal pro‐B‐type natriuretic peptide) was associated with incident AF (adjusted hazard ratio [HR] per SD higher concentration: 2.11; 95% CI, 1.75, 2.55), as was log‐high‐sensitivity troponin T (HR 1.42; 95% CI, 1.20, 1.68). These associations showed a dose–response relationship in categorical analyses. Although log‐soluble ST‐2 was associated with AF risk in continuous models (HR per SD higher concentration 1.35; 95% CI, 1.16, 1.58), this association was not consistent in categorical analyses. Log‐galectin‐3 (HR 1.05; 95% CI, 0.91, 1.22) and log‐growth differentiation factor‐15 (HR 1.16; 95% CI, 0.96, 1.40) were not significantly associated with incident AF.

Conclusions

We found strong associations between higher NT‐proBNP (N‐terminal pro‐B‐type natriuretic peptide) and high‐sensitivity troponin T concentrations, and the risk of incident AF in a large cohort of participants with chronic kidney disease. Increased atrial myocardial stretch and myocardial cell injury may be implicated in the high burden of AF in patients with chronic kidney disease.

[The Nephrological Aspects of the Use of Rivaroxaban and Other Direct Peroral Anticoagulants in Non-Valvular Atrial Fibrillation]

Chronic kidney disease (CKD) is a powerful cardiovascular risk factor, its presence is accompanied by an increased risk of hospitalization for exacerbation of chronic heart failure (CHF), adverse outcomes in myocardial infarction, and cardiovascular mortality. Among the adverse events, an increased risk of atrial fibrillation (AF) should be noted. This article contains discussion of current approaches to the treatment of AF in patients with different stages of CKD, data on benefits of certain direct oral anticoagulants, as well as comparative characteristics of therapy with direct oral anticoagulants and warfarin. Pharmacokinetics and pharmacodynamics of direct oral anticoagulants, which determine the features of therapy in CKD, are also considered.

Rates of Cardiac Rhythm Abnormalities in Patients with CKD and Diabetes

BACKGROUND AND OBJECTIVES

Cardiac arrhythmias increase mortality and morbidity in CKD. We evaluated the rates of subclinical arrhythmias in a population with type 2 diabetes and patients with moderate to severe CKD who were not on dialysis.

DESIGN, SETTING, PARTICIPANTS & MEASUREMENTS

This is a prospective observational study, using continuous ambulatory cardiac monitors to determine the rate of atrial and ventricular arrhythmias, as well as conduction abnormalities in this group.

RESULTS

A total of 38 patients (34% women), with mean eGFR of 38±13 ml/min per 1.73 m², underwent ambulatory cardiac monitoring for 11.2±3.9 days. The overall mean rate of any cardiac arrhythmia was 88.8 (95% confidence interval [95% CI], 27.1 to 184.6) episodes per person-year (PY). A history of cardiovascular disease was associated with a higher rate of detected arrhythmia (rate ratio, 5.87; 95% CI, 1.37 to 25.21; P<0.001). The most common arrhythmia was atrial fibrillation, which was observed in two participants with known atrial fibrillation and was a new diagnosis in four patients (11%), none of whom experienced symptoms. Overall, atrial fibrillation episodes occurred at a rate of 37.6 (95% CI, 2.4 to 112.3) per PY. Conduction abnormalities were found in eight patients (21%), a rate of 26.5 (95% CI, 4.2 to 65.5) per PY. Rates of ventricular arrhythmias were low (14.5 per PY; 95% CI, 4.3 to 32.0) and driven by premature ventricular contractions.

CONCLUSIONS

Cardiac rhythm abnormalities are common in patients with diabetes with moderate to severe CKD not requiring dialysis. Rates of atrial fibrillation are high and episodes are asymptomatic. Future studies are needed to determine the role of screening and upstream therapy of cardiac arrhythmias in this group.

Patients with Atrial Fibrillation and Chronic Kidney Disease More Often Undergo Angioplasty of Left Main Coronary Artery - a 867 Patient Study

BACKGROUND/AIMS

Several studies have implicated atrial fibrillation (AF) as a contributing factor in chronic kidney disease (CKD) and cardiovascular events. The prevalence of coronary artery disease (CAD) in patients with AF varies substantially from 17% to 46.5%. There are only few studies concerning renal function in population with AF undergoing coronary angiography. The aim of the present study was to assess which type of AF is dominant in CKD population scheduled for coronary angiography and if it can influence patients' outcome, the association between renal impairment and the type of coronary procedures in AF patients and the influence of renal function on in-hospital mortality.

METHODS

We retrospectively studied 867 patients with AF hospitalized due to coronary angiography in two year time. The cut off value of CKD was eGFR ≤ 60 ml/min./1.73m2 evaluated by CKD-EPI formula.

RESULTS

A total of 867 patients with AF (44% women; mean age 72±10 years) were included in the analysis. The mean eGFR was 44±11ml/min./1.73m2 in patients with CKD and 89±18 ml/min./1.73m2 in patients with preserved renal function. Patients with CKD and AF were older (p< 0.001), had more often diabetes (p=0.009), heart failure (p< 0.001) and anaemia (p< 0.001). Patients with CKD and AF had more often permanent type of AF (p< 0.001). In CKD patients CHA2DS2VASc score was 4.3±1.5 and HAS-BLED score was 2.0±1.2 and it was significantly higher as compared to population with preserved renal function (p< 0.001, p=0.02, respectively). The use of oral anticoagulation was less frequent in CKD group (p< 0.001) although these patients had higher CHA2DS2VASc score. Patients with AF and CKD were more often admitted due to myocardial infarction (STEMI or NSTEMI) (p=0.02, p< 0.001, respectively) and more often underwent percutaneous coronary intervention (PCI) (p=0.01). Among coronary arteries the percutaneous coronary intervention (PCI) of left main artery was done more frequently in CKD patients (p=0.01). Among CKD population in-hospital mortality was significantly higher in patients with eGFR < 30 ml/min (p< 0.001).

CONCLUSION

Patients with CKD had more often permanent type of AF. Percutaneous interventions of the left main coronary artery, the only elective procedures influencing patients' prognosis, were done more frequently in CKD patients with AF. In-hospital mortality was significantly higher in patients with severe renal impairment. Despite the higher risk of ischaemic stroke in CKD group the use of oral anticoagulation therapy was significantly less frequent and the patients were deprived of the confirmed benefits of such treatment.

Cardiovascular Events after New-Onset Atrial Fibrillation in Adults with CKD: Results from the Chronic Renal Insufficiency Cohort (CRIC) Study

BACKGROUND

Atrial fibrillation (AF), the most common sustained arrhythmia in CKD, is associated with poor clinical outcomes in both patients without CKD and patients with dialysis-treated ESRD. However, less is known about AF-associated outcomes in patients with CKD who do not require dialysis.

METHODS

To prospectively examine the association of new-onset AF with subsequent risks of cardiovascular disease events and death among adults with CKD, we studied participants enrolled in the Chronic Renal Insufficiency Cohort Study who did not have AF at baseline. Outcomes included heart failure, myocardial infarction, stroke, and death occurring after diagnosis of AF. We used Cox regression models and marginal structural models to examine the association of incident AF with subsequent risk of cardiovascular disease events and death, adjusting for patient characteristics, laboratory values, and medication use.

RESULTS

Among 3080 participants, 323 (10.5%) developed incident AF during a mean 6.1 years of follow-up. Compared with participants who did not develop AF, those who did had higher adjusted rates of heart failure (hazard ratio [HR], 5.17; 95% confidence interval [95% CI], 3.89 to 6.87), myocardial infarction (HR, 3.64; 95% CI, 2.50 to 5.31), stroke (HR, 2.66; 95% CI, 1.50 to 4.74), and death (HR, 3.30; 95% CI, 2.65 to 4.12). These associations remained robust with additional adjustment for biomarkers of inflammation, cardiac stress, and mineral metabolism; left ventricular mass; ejection fraction; and left atrial diameter.

CONCLUSIONS

Incident AF is independently associated with two- to five-fold increased rates of developing subsequent heart failure, myocardial infarction, stroke, or death in adults with CKD. These findings have important implications for cardiovascular risk reduction.

Association of Fibroblast Growth Factor 23 With Atrial Fibrillation in Chronic Kidney Disease, From the Chronic Renal Insufficiency Cohort Study

IMPORTANCE

Levels of fibroblast growth factor 23 (FGF23) are elevated in chronic kidney disease (CKD) and strongly associated with left ventricular hypertrophy, heart failure, and death. Whether FGF23 is an independent risk factor for atrial fibrillation in CKD is unknown.

OBJECTIVE

To investigate the association of FGF23 with atrial fibrillation in CKD.

DESIGN, SETTING, AND PARTICIPANTS

Prospective cohort study of 3876 individuals with mild to severe CKD who enrolled in the Chronic Renal Insufficiency Cohort Study between June 19, 2003, and September 3, 2008, and were followed up through March 31, 2013.

EXPOSURES

Baseline plasma FGF23 levels.

MAIN OUTCOMES AND MEASURES

Prevalent and incident atrial fibrillation.

RESULTS

The study cohort comprised 3876 participants. Their mean (SD) age was 57.7 (11.0) years, and 44.8% (1736 of 3876) were female. Elevated FGF23 levels were independently associated with increased odds of prevalent atrial fibrillation (n = 660) after adjustment for cardiovascular and CKD-specific factors (odds ratio of highest vs lowest FGF23 quartile, 2.30; 95% CI, 1.69-3.13; P < .001 for linear trend across quartiles). During a median follow-up of 7.6 years (interquartile range, 6.3-8.6 years), 247 of the 3216 participants who were at risk developed incident atrial fibrillation (11.9 events per 1000 person-years). In fully adjusted models, elevated FGF23 was independently associated with increased risk of incident atrial fibrillation after adjustment for demographic, cardiovascular, and CKD-specific factors, and other markers of mineral metabolism (hazard ratio of highest vs lowest FGF23 quartile, 1.59; 95% CI, 1.00-2.53; P = .02 for linear trend across quartiles). The results were unchanged when further adjusted for ejection fraction, but individual adjustments for left ventricular mass index, left atrial area, and interim heart failure events partially attenuated the association of elevated FGF23 with incident atrial fibrillation.

CONCLUSIONS AND RELEVANCE

Elevated FGF23 is independently associated with prevalent and incident atrial fibrillation in patients with mild to severe CKD. The effect may be partially mediated through a diastolic dysfunction pathway that includes left ventricular hypertrophy, atrial enlargement, and heart failure events.

Risk profiles for acute health events after incident atrial fibrillation in patients with end-stage renal disease on hemodialysis

Background

Little is known about the cardiovascular risks of incident atrial fibrillation/flutter (AF) in patients with end-stage renal disease (ESRD) undergoing hemodialysis (HD).

Methods

We studied older US patients who newly initiated HD for ESRD (2006-11) and who had not previously been diagnosed with AF, stroke, myocardial infarction (MI) or hip fracture. We used Cox regression with AF as a time-varying covariate, adjusted for socio-demographic characteristics and comorbidities to estimate hazard ratios [HRs (95% confidence intervals)] for the events of ischemic stroke, MI and death. Hip fracture served as a negative control outcome.

Results

We identified 85 377 older patients (mean age: 76.5 years) who initiated HD; of these, 14.3% were subsequently diagnosed with AF (14.9% thereof as primary diagnosis) and 49.8% died during follow-up. Incident AF was associated with nine times higher adjusted mortality during the first 30 days [9.2 (8.8-9.6)], 5-fold higher mortality between 31 and 90 days [4.6 (4.3-4.8)] and double the mortality beyond 90 days from first AF diagnosis [2.2 (2.1-2.3)]. Incident AF was similarly associated with higher adjusted risk of ischemic stroke: 2.1 (1.6-2.7) during the first 30 days, 2.5 (2.0-3.0) between 31 and 90 days and 1.5 (1.3-1.7) beyond 90 days. Similar findings were obtained for MI. However, the risk of hip fracture was only marginally increased following AF diagnosis [≤30 days: 1.1 (0.7-1.6); 31-90 days: 1.4 (1.0-1.8); >90 days: 1.2 (1.1-1.4)]. All associations were attenuated and the association with hip fracture was null when incident AF was defined by a primary diagnosis code.

Conclusions

AF was strongly associated with increased risks of ischemic stroke, MI and death, with risks highest soon after AF diagnosis but extending beyond 90 days.

Cause-Specific Mortality in Patients with Chronic Kidney Disease and Atrial Fibrillation

BACKGROUND

Atrial fibrillation (AF) is associated with death in patients with chronic kidney disease (CKD). We examined the associations between AF and cause-specific mortality in a large CKD population.

METHODS

We included 62,459 patients with estimated glomerular filtration rate 15-59 mL/min/1.73 m2 (6,639 patients with AF and 55,820 without AF) followed in a large health care system. Outcomes included overall and cause-specific deaths (a) cardiovascular; (b) malignancy; and (c) non-cardiovascular/non-malignancy causes. Cox regression models for overall mortality and separate competing risk models for each major cause of death category were used to evaluate their respective associations with AF.

RESULTS

During a median follow-up of 4.1 years, 19,094 patients died; cause of death was known for 18,854 patients. After multivariable adjustment (demographics, comorbidities, relevant laboratory data, medication use, and kidney function), AF was associated with 23% (95% CI 18-29%) higher risk of all-cause mortality, 45% (95% CI 31-61%) higher risk of cardiovascular mortality and 13% (95% CI 3-22%) lower risk of malignancy-related mortality. Exclusion of patients with malignancy yielded similar results except for a lack of association between AF and malignancy-related deaths. Results were consistent across various stages of CKD.

CONCLUSIONS

In a non-dialysis-dependent CKD population, the presence of AF was associated with higher all-cause and cardiovascular mortality. These data suggest that patients with both CKD and AF are at high cardiovascular risk, and thus clinical practice (or trials) should aim at reducing the overall excess cardiovascular mortality (not stroke alone) in patients with AF and CKD.

Non-Vitamin K-Dependent Oral Anticoagulants for Nonvalvular Atrial Fibrillation in Patients With CKD: Pragmatic Considerations for the Clinician

Management of atrial fibrillation (AF) in patients with advanced chronic kidney disease (CKD) poses a complex conundrum because of higher risks for both thromboembolic and bleeding complications compared to the general population. This makes it particularly important for clinicians to carefully weigh the risks versus benefits of anticoagulation therapy to determine the individualized net clinical benefit for every patient. During the past few years, 4 non-vitamin K-dependent oral anticoagulant (NOAC) agents have supplemented warfarin in the therapeutic armamentarium for the prevention of systemic thromboembolism in nonvalvular AF. However, the use of NOACs in CKD specifically mandates a nuanced understanding due to their varying dependence on renal clearance, with resultant safety implications related to either underdosing (thromboembolism) or excessive drug exposure (bleeding). This pragmatic review highlights unique considerations pertaining to accurate estimation and temporal monitoring of kidney function in the context of NOAC use with specific clinical deliberations and variables when determining whether an NOAC is appropriate for a patient with CKD. The dependence of NOACs on renal clearance and several troubling safety signals in the published literature suggest that it is vital for nephrologists to be active members of a multidisciplinary team caring for these high-risk patients with CKD and AF.

eGFR and Albuminuria in Relation to Risk of Incident Atrial Fibrillation: A Meta-Analysis of the Jackson Heart Study, the Multi-Ethnic Study of Atherosclerosis, and the Cardiovascular Health Study

BACKGROUND AND OBJECTIVES

The incidence of atrial fibrillation is high in ESRD, but limited data are available on the incidence of atrial fibrillation across a broad range of kidney function. Thus, we examined the association of eGFR and urine albumin-to-creatinine ratio with risk of incident atrial fibrillation.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We meta-analyzed three prospective cohorts: the Jackson Heart Study, the Multi-Ethnic Study of Atherosclerosis, and the Cardiovascular Health Study. Cox regression models were performed examining the association of eGFR and urine albumin-to-creatinine ratio with incident atrial fibrillation adjusting for demographics and comorbidity. In additional analyses, we adjusted for measures of subclinical cardiovascular disease (by electrocardiogram and cardiac imaging) and interim heart failure and myocardial infarction events.

RESULTS

In the meta-analyzed study population of 16,769 participants without prevalent atrial fibrillation, across categories of decreasing eGFR (eGFR>90 [reference], 60-89, 45-59, 30-44, and <30 ml/min per 1.73 m2), there was a stepwise increase in the adjusted risk of incident atrial fibrillation: hazard ratios (95% confidence intervals) were 1.00, 1.09 (0.97 to 1.24), 1.17 (1.00 to 1.38), 1.59 (1.28 to 1.98), and 2.03 (1.40 to 2.96), respectively. There was a stepwise increase in the adjusted risk of incident atrial fibrillation across categories of increasing urine albumin-to-creatinine ratio (urine albumin-to-creatinine ratio <15 [reference], 15-29, 30-299, and ≥300 mg/g): hazard ratios (95% confidence intervals) were 1.00, 1.04 (0.83 to 1.30), 1.47 (1.20 to 1.79), and 1.76 (1.18 to 2.62), respectively. The associations were consistent after adjustment for subclinical cardiovascular disease measures and interim heart failure and myocardial infarction events.

CONCLUSIONS

In this meta-analysis of three cohorts, reduced eGFR and elevated urine albumin-to-creatinine ratio were significantly associated with greater risk of incident atrial fibrillation, highlighting the need for further studies to understand mechanisms linking kidney disease with atrial fibrillation.

The association between insulin resistance and atrial fibrillation: A cross-sectional analysis from SPRINT (Systolic Blood Pressure Intervention Trial)

It is unclear whether metabolic syndrome (MetS) is associated with atrial fibrillation (AF) in an older population with greater cardiovascular risk, including those with chronic kidney disease. The authors investigated the association between MetS and AF in participants in SPRINT (Systolic Blood Pressure Intervention Trial). MetS was defined based on the Modified Third National Cholesterol Education Program. The baseline prevalence rate for MetS was 55%, while 8.2% of the participants had AF. In multivariate regression analyses, AF was not associated with presence of MetS in either chronic kidney disease or non-chronic kidney disease subgroups. Age, race, history of cardiovascular diseases, decreased triglycerides, decreased pulse pressure, and albuminuria remained significantly associated with AF risk. In contrast to the general population, MetS was not associated with AF in the older population with increased cardiovascular risk studied in SPRINT.

How Dangerous Is Hyperkalemia?

Hyperkalemia is a potentially life-threatening electrolyte disorder appreciated with greater frequency in patients with renal disease, heart failure, and with use of certain medications such as renin angiotensin aldosterone inhibitors. The traditional views that hyperkalemia can be reliably diagnosed by electrocardiogram and that particular levels of hyperkalemia confer cardiotoxic risk have been challenged by several reports of patients with atypic presentations. Epidemiologic data demonstrate strong associations of morbidity and mortality in patients with hyperkalemia but these associations appear disconnected in certain patient populations and in differing clinical presentations. Physiologic adaptation, structural cardiac disease, medication use, and degree of concurrent illness might predispose certain patients presenting with hyperkalemia to a lower or higher threshold for toxicity. These factors are often overlooked; yet data suggest that the clinical context in which hyperkalemia develops is at least as important as the degree of hyperkalemia is in determining patient outcome. This review summarizes the clinical data linking hyperkalemia with poor outcomes and discusses how the efficacy of certain treatments might depend on the clinical presentation.

Determinants of Left Atrial Volume in Patients with Atrial Fibrillation

Introduction

Left atrial (LA) enlargement is an important risk factor for incident stroke and a key determinant for the success of rhythm control strategies in patients with atrial fibrillation (AF). However, factors associated with LA volume in AF patients remain poorly understood.

Methods

Patients with paroxysmal or persistent AF were enrolled in this study. Real time 3-D echocardiography was performed in all participants and analyzed offline in a standardized manner. We performed stepwise backward linear regression analyses using a broad set of clinical parameters to determine independent correlates for 3-D LA volume.

Results

We included 210 patients (70.9% male, mean age 61±11years). Paroxysmal and persistent AF were present in 95 (45%) and 115 (55%) patients, respectively. Overall, 115 (55%) had hypertension, 11 (5%) had diabetes, and 18 (9%) had ischemic heart disease. Mean indexed LA volume was 36±12ml/m². In multivariable models, significant associations were found for female sex (β coefficient -10.51 (95% confidence interval (CI) -17.85;-3.16), p = 0.0053), undergoing cardioversion (β 11.95 (CI 5.15; 18.74), p = 0.0006), diabetes (β 14.23 (CI 2.36; 26.10), p = 0.019), body surface area (BSA) (β 34.21 (CI 19.30; 49.12), p<0.0001), glomerular filtration rate (β -0.21 (CI -0.36; -0.06), p = 0.0064) and plasma levels of NT-pro brain natriuretic peptide (NT-proBNP) (β 6.79 (CI 4.05; 9.52), p<0.0001), but not age (p = 0.59) or hypertension (p = 0.42). Our final model explained 52% of the LA volume variability.

Conclusions

In patients with AF, the most important correlates with LA volume are sex, BSA, diabetes, renal function and NT-proBNP, but not age or hypertension. These results may help to refine rhythm control strategies in AF patients.

Atrial Fibrillation and Risk of ESRD in Adults with CKD

BACKGROUND AND OBJECTIVES

Atrial fibrillation frequently complicates CKD and is associated with adverse outcomes. Progression to ESRD is a major complication of CKD, but the link with atrial fibrillation has not been fully delineated. In this study, we examined the association of incident atrial fibrillation with the risk of ESRD in patients with CKD.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We studied participants in the prospective Chronic Renal Insufficiency Cohort Study without atrial fibrillation at entry. Incident atrial fibrillation was identified by study visit ECGs, self-report, and hospital discharge diagnostic codes, with confirmation by physician adjudication. ESRD through 2012 was ascertained by participant self-report, medical records, and linkage to the US Renal Data System. Data on potential confounders were obtained from self-report, study visits, and laboratory tests. Marginal structural models were used to study the potential association of incident atrial fibrillation with risk of ESRD after adjustment for time-dependent confounding.

RESULTS

Among 3091 participants, 172 (5.6%) developed incident atrial fibrillation during follow-up. During mean follow-up of 5.9 years, 43 patients had ESRD that occurred after development of incident atrial fibrillation (11.8/100 person-years) compared with 581 patients without incident atrial fibrillation (3.4/100 person-years). In marginal structural models with inverse probability weighting, incident atrial fibrillation was associated with a substantially higher rate of ESRD (hazard ratio, 3.2; 95% confidence interval, 1.9 to 5.2). This association was consistent across important subgroups by age, sex, race, diabetes status, and baseline eGFR.

CONCLUSIONS

Incident atrial fibrillation was associated with higher risk of developing ESRD in CKD. Additional study is needed to identify potentially modifiable pathways through which atrial fibrillation was associated with a higher risk of progression to ESRD. More aggressive monitoring and treatment of patients with CKD and atrial fibrillation may improve outcomes in this high-risk population.

Stroke and Chronic Kidney Disease: Epidemiology, Pathogenesis, and Management Across Kidney Disease Stages

Cerebrovascular disease and stroke are very common at all stages of chronic kidney disease (CKD), likely representing both shared risk factors as well as synergy among risk factors. More subtle ischemic brain lesions may be particularly common in the CKD population, with subtle manifestations including cognitive impairment. For individuals with nondialysis CKD, the prevention, approach to, diagnosis, and management of stroke is similar to the general, non-CKD population. For individuals with end-stage renal disease, far less is known regarding strategies to prevent stroke. Stroke prophylaxis using warfarin in dialysis patients with atrial fibrillation in particular remains of uncertain benefit. End-stage renal disease patients can be managed aggressively in the setting of acute stroke. Outcomes after stroke at all stages of CKD are poor, and improving these outcomes should be the subject of future clinical trials.

Epidemiologic insights on the role of fibroblast growth factor 23 in cardiovascular disease

PURPOSE OF REVIEW

Fibroblast growth factor 23 (FGF23) regulates phosphate and vitamin D homeostasis and rises as kidney function declines. Animal studies have demonstrated direct and indirect effects of FGF23 that may promote heart disease. Herein, we review the recent epidemiologic literature evaluating the relationship between FGF23 and cardiovascular disease.

RECENT FINDINGS

In observational prospective studies, higher FGF23 associates with a greater risk of incident cardiovascular disease including ischemic heart disease, stroke, heart failure, and atrial fibrillation. These studies establish a temporal sequence of events over long-term follow-up that suggest a possible role of FGF23 in cardiovascular disease pathogenesis. In most studies, risk is generally graded; however, in the largest study to date, higher FGF23 within the low-normal range was not associated with higher risk. In several recent studies higher FGF23 associated more strongly with the risk of congestive heart failure compared with atherosclerotic events, a finding consistent with surrogate endpoints and animal experiments. Currently, the utility of FGF23 as a predictive biomarker of cardiovascular risk is not established, and interventions to reduce FGF23 need to be studied to confirm its possible pathophysiologic role.

SUMMARY

Higher FGF23 is associated with the subsequent development of cardiovascular disease, and perhaps most notably heart failure, in a growing number of studies. These findings bolster ongoing efforts to lower FGF23 using strategies to reduce phosphate intake and absorption.