Sudden Cardiac Death in End-Stage Renal Disease

Cardiac arrhythmia and hypoglycaemia among individuals with and without diabetes receiving haemodialysis (the CADDY study): a Danish multicentre cohort study

AIMS/HYPOTHESIS

We aimed to examine arrhythmias and hypoglycaemia among individuals with and without diabetes who are receiving haemodialysis and to investigate the association between arrhythmias and hypoglycaemia, hyperglycaemia and glycaemic variability.

METHODS

This prospective multicentre cohort study included 70 participants on maintenance haemodialysis (35 with diabetes and 35 without diabetes). We employed implantable cardiac monitors for continuous heart rhythm monitoring in combination with periodic use of continuous glucose monitoring. Logistic-regression-type linear mixed models were used to examine associations between arrhythmias and glycaemic measures.

RESULTS

During 18 months of follow-up, clinically significant arrhythmias (bradyarrhythmia and ventricular tachycardia) were identified in 12 (34%) participants with diabetes and 11 (31%) without diabetes. Atrial fibrillation was detected in 13 (37%) participants with diabetes and 14 (40%) without, while other supraventricular tachycardia was detected in seven (20%) and 11 (31%) participants with and without diabetes, respectively. Hypoglycaemia (sensor glucose <3.9 mmol/l) was observed in 27 (77%) participants with diabetes and 32 (91%) without diabetes. Compared with euglycaemia, hypoglycaemia was associated with an increased rate of arrhythmias among participants without diabetes (incidence rate ratio [IRR] 3.13 [95% CI 1.49, 6.55]), while hyperglycaemia (sensor glucose >10.0 mmol/l) was associated with a decreased rate of arrhythmias among participants with diabetes (IRR 0.58 [95% CI 0.37, 0.92]). Glycaemic variability showed no association with arrhythmias regardless of the presence of diabetes.

CONCLUSIONS/INTERPRETATION

Arrhythmias and hypoglycaemia were common in those undergoing haemodialysis regardless of diabetes status. Our data suggest a temporal relationship between arrhythmias and glucose level in both individuals with and without diabetes.

TRIAL REGISTRATION

Clinicaltrials.gov: NCT04841304.

Association between elevated serum parathyroid hormone and QTc interval prolongation in chronic kidney disease patients

PURPOSE

Heart rate-corrected (QTc) interval prolongation is frequently linked to fatal arrhythmias and sudden cardiac death in chronic kidney disease (CKD) patients. In this cross-sectional study, we assessed the prevalence of prolonged QTc intervals and identified clinical factors associated with them across different stages of kidney failure.

METHODS

723 patients with CKD stages 2-5 who had electrocardiogram records available were analyzed retrospectively. QTc intervals were calculated by correcting the QT intervals for all patients included in the study. QTc interval prolongation defined as a QTc interval ˃ 440 ms was assessed for its prevalence and its association with various clinical factors.

RESULTS

A total of 723 patients with CKD stages 2-5 were finally included in this study, among which 420 (58.1%) were male. The average age of the participants was 48.2 ± 14.6 years old. In patients with CKD stages 2-4, the prevalence of QTc interval prolongation was 26%, 24.1%, and 37.8%, respectively. Among patients with CKD stage 5, those not on dialysis had a prevalence of 63%, while those undergoing dialysis had a prevalence of 74.3%. Multivariate logistic regression analysis revealed that elevated levels of parathyroid hormone (PTH) were significantly associated with an increased risk of QTc intervals prolongation in CKD patients (aOR = 1.384, 95% CI 1.173-1.632; P < 0.001). This suggests that higher PTH levels may contribute to QTc interval prolongation in this population. The patients were then grouped by CKD stages. Elevated PTH levels were independently associated with an increased risk of QTc interval prolongation specifically in CKD stages 4 and 5 patients who were not on dialysis. After adjusting for potential confounders, this association remained significant (CKD stage 4: aOR = 2.571, 95% CI 1.030-6.416; P < 0.001; CKD stage 5, non-dialysis: aOR = 1.333, 95% CI 1.063-1.671; P < 0.001).

CONCLUSION

In patients with CKD, the prevalence of QTc prolongation increases with advancing CKD stages. Specially, among patients with CKD stage 4 and stage 5 who were not on dialysis, elevated PTH levels were independently associated with an increased risk of QTc interval prolongation.

Adequacy of Dialysis and Incidence of Atrial Fibrillation in Patients Undergoing Hemodialysis

BACKGROUND

Atrial fibrillation (AF) can lead to stroke, heart failure, and mortality and has a greater prevalence in dialysis patients than in the general population. Several studies have suggested that uremic toxins may contribute to the development of AF. However, the association between dialysis adequacy and incident AF has not been well established.

METHODS

In this retrospective nationwide cohort study, we analyzed data from the Korean National Periodic Hemodialysis Quality Assessment from 2013 to 2015 of patients who received outpatient maintenance hemodialysis 3× a week. The main exposure was single pooled Kt/V (spKt/V), which is the dialysis adequacy index, and the primary outcome was the development of AF. For the primary analysis, patients were categorized into quartiles according to baseline spKt/V. The lowest quartile, representing the lowest adequacy, was used as the reference group. Fine-Gray subdistribution hazard models were used, treating all-cause mortality as a competing risk.

RESULTS

Of 25 173 patients, the mean age was 60 (51-69) years, and 14 772 (58.7%) were men. During a median follow-up of 5.7 years, incident AF occurred in a total of 3883 (15.4%) patients. Participants with a higher spKt/V tended to have lower AF incidence. In survival analysis, a graded association was observed between the risk of incident AF and spKt/V quartiles: subdistribution hazard ratios and 95% CIs for the second, third, and the highest quartile compared with the lowest quartile were 0.90 (95% CI, 0.82-0.98), 0.84 (95% CI, 0.77-0.93), and 0.79 (95% CI, 0.72-0.88), respectively.

CONCLUSIONS

This nationwide cohort study showed that a higher spKt/V is associated with a reduced risk of incident AF. These findings suggests that reducing uremic toxin burden through enhanced dialysis clearance may be associated with a lower risk of AF development in patients undergoing maintenance hemodialysis.

Cardiac arrhythmia and hypoglycaemia in patients receiving haemodialysis with and without diabetes (the CADDY study): protocol for a Danish multicentre cohort study

INTRODUCTION

Patients receiving haemodialysis are at increased risk of arrhythmias and sudden cardiac death, but data on arrhythmia burden and the pathophysiology remain limited. Among potential risk factors, hypoglycaemia is proposed as a possible trigger of lethal arrhythmias. The development of implantable loop recorders (ILR) and continuous glucose monitoring (CGM) enables long-term continuous ECG and glycaemic monitoring. The current article presents the protocol of a study aiming to increase the understanding of arrhythmias and risk factors in patients receiving haemodialysis. The findings will provide a detailed exploration of the burden and nature of arrhythmias in these patients including the potential association between hypoglycaemia and arrhythmias.

METHODS AND ANALYSIS

The study is an investigator-initiated, prospective, multicentre cohort study recruiting 70 patients receiving haemodialysis: 35 with diabetes and 35 without diabetes. Participants are monitored with ILRs and CGM for 18 months follow-up. Data collection further includes a monthly collection of predialysis blood samples and dialysis parameters. The primary outcome is the presence of clinically significant arrhythmias defined as a composite of bradycardia, ventricular tachycardia, or ventricular fibrillation. Secondary outcomes include the characterisation of clinically significant arrhythmias and other arrhythmias, glycaemic characteristics, and mortality. The data analyses include an assessment of the association between arrhythmias and hypoglycaemia and hyperglycaemia, baseline clinical variables, and parameters related to kidney failure and the haemodialysis procedure.

ETHICS AND DISSEMINATION

The study has been approved by the Ethics Committee of the Capital Region of Denmark (H-20069767). The findings will be presented at national and international congresses as well as in international peer-reviewed scientific journals.

TRIAL REGISTRATION NUMBER

NCT04841304.

Non-linear relationship between basal serum albumin concentration and cardiac arrest in critically ill patients with end-stage renal disease: a cross-sectional study

OBJECTIVES

The aim of our study was to investigate the association between serum albumin concentration and the risk of cardiac arrest in critically ill patients with end-stage renal disease in the intensive care unit (ICU).

DESIGN

This was a secondary analysis.

SETTING

The Phillip electronic-ICU collaborative database from 2014 to 2015.

PARTICIPANTS

This study included 4990 critically ill patients diagnosed with end-stage renal disease.

PRIMARY AND SECONDARY OUTCOME MEASURES

The exposure of interest was serum albumin concentration. The outcome variable was cardiac arrest.

RESULTS

A non-linear relationship was observed between serum albumin concentration and risk of cardiac arrest, with an inflection point of 3.26 g/dL after adjusting for potential confounders. The effect sizes and the CIs on the left and right sides of the inflection point were 0.88 (0.65 to 1.19) and 0.32 (0.16 to 0.64), respectively.

CONCLUSIONS

Within an albumin range of 3.26-5.6 g/dL, each 1 g/dL increase in serum levels is associated with a 68% decrease of the risk of cardiac arrest in critically ill patients with end-stage renal disease.