Nocturnal Home Hemodialysis Associates with Improvement of Electrocardiographic Features Linked to Sudden Cardiac Death

Long-Term In-Center Nocturnal Hemodialysis Improves Renal Anemia and Malnutrition and Life Quality of Older Patients with Chronic Renal Failure

Background

Older patients with chronic renal failure (CRF) which currently is referred to as end-stage renal disease (ESRD) are associated with higher mortality. In-center nocturnal dialysis (INHD) is a new blood purification model, which is characterized by longer sessions and nighttime administration. However, no data for the efficacy of INHD in older patients with ESRD are available. This study is to analyze the effect of INHD in the treatment of older patients with ESRD.

Methods

A retrospective, observational study was conducted in a university teaching hospital. Seventy-two patients with ESRD receiving INHD were enrolled. They were divided into the older ESRD patients (age ≥60) group (n = 22) and the non-older ESRD patients (age <60) group (n = 50). The causes of older ESRD patients and non-older ESRD patients receiving INHD were analyzed. Differences of laboratory test indicators of older patients with ESRD before INHD and after INHD were compared. Quality of life for older ESRD patients receiving INHD was assessed by using the Kidney Disease Quality of Life-36 Instrument (KDQOL-36).

Results

Serum concentration of hemoglobin and serum concentration of albumin of older patients with ESRD increased significantly after INHD (p < 0.05). There were similar results in the non-older cohort (p ≤ 0.05). Scores of five KDQOL-36 subscales increased significantly after INHD (p ≤ 0.001) indicated that the quality of life for old patients with ESRD was significantly improved after INHD.

Conclusion

INHD is an effective blood purification therapy that can improve the condition of renal anemia, and it may provide a potential positive impact in the malnutrition of older and non-older patients with ESRD. INHD can improve the quality of life of older patients with ESRD. The results will provide a basis for formulating new policies of blood purification therapy for older patients.

Cardiovascular Benefits of Extended-Time Nocturnal Hemodialysis

Hemodialysis (HD) remains the most utilized treatment for End-Stage Kidney Disease (ESKD) globally, mainly as conventional HD administered in 4 h sessions thrice weekly. Despite advances in HD delivery, patients with ESKD carry a heavy cardiovascular morbidity and mortality burden. This is associated with cardiac remodeling, left ventricular hypertrophy (LVH), myocardial stunning, hypertension, decreased heart rate variability, sleep apnea, coronary calcification and endothelial dysfunction. Therefore, intensive HD regimens closer to renal physiology were developed. They include longer, more frequent dialysis or both. Among them, Nocturnal Hemodialysis (NHD), carried out at night while asleep, provides efficient dialysis without excessive interference with daily activities. This regimen is closer to the physiology of the native kidneys. By providing increased clearance of small and middle molecular weight molecules, NHD can ameliorate uremic symptoms, control hyperphosphatemia and improve quality of life by allowing a liberal diet and free time during the day. Lastly, it improves reproductive biology leading to successful pregnancies. Conversion from conventional to NHD is followed by improved blood pressure control with fewer medications, regression of LVH, improved LV function, improved sleep apnea, and stabilization of coronary calcifications. These beneficial effects have been associated, among others, with better extracellular fluid volume control, improved endothelial- dependent vasodilation, decreased total peripheral resistance, decreased plasma norepinephrine levels and restoration of heart rate variability. Some of these effects represent improvements in outcomes used as surrogates of hard outcomes related to cardiovascular morbidity and mortality. In this review, we consider the cardiovascular effects of NHD.

Asystole episodes and bradycardia in patients with end-stage renal disease

BACKGROUND

Knowledge of arrhythmias in patients with end-stage renal disease (ESRD) is mainly based on ambulatory electrocardiography (ECG) studies and observations during haemodialysis. We used insertable cardiac monitors to define the prevalence of arrhythmias, focusing on bradyarrhythmias, in ESRD patients treated with several dialysis modes including home therapies. Moreover, we assessed whether these arrhythmias were detected in baseline or ambulatory ECG recordings.

METHODS

Seventy-one patients with a subcutaneously insertable cardiac monitor were followed for up to three years. Asystole (≥4.0 secs) and bradycardia (heart rate <30 bpm for ≥4 beats) episodes, ventricular tachyarrhythmias and atrial fibrillation were collected and verified visually. A baseline ECG and a 24-48-hour ambulatory ECG were recorded at recruitment and once a year thereafter.

RESULTS

At recruitment, forty-four patients were treated in in-center haemodialysis, 12 in home haemodialysis and 15 in peritoneal dialysis. During a median follow-up of 34.4 months, 18 (25.4%) patients had either an asystolic or a bradycardic episode. The median length of each patient's longest asystole was 6.6 seconds and that of a bradycardia 13.5 seconds. Ventricular tachyarrhythmias were detected in 16 (23%) patients, and atrial fibrillation in 34 (51%) patients. In-center haemodialysis and type II diabetes were significantly more frequent among those with bradyarrhythmias whereas no bradyarrhythmias were found in home haemodialysis. No bradyarrhythmias were evident in baseline or ambulatory ECG recordings.

CONCLUSIONS

Remarkably many patients with ESRD had bradycardia or asystolic episodes, but these arrhythmias were not detected by baseline or ambulatory ECG.

Protein carbamylation is associated with heart failure and mortality in diabetic patients with end-stage renal disease

Serum carbamylated albumin (C-Alb) levels are associated with excess mortality in patients with diabetic end stage renal disease. To gain insight into the pathophysiology of carbamylation, we determined associations between C-Alb and causes of death in patients on chronic hemodialysis. The Die Deutsche Diabetes Dialyse Studie (4D study) was a randomized controlled trial testing the effects of atorvastatin on survival in diabetic patients on dialysis during a median follow-up of 4 years. We stratified 1,161 patients by C-Alb to see if differences in carbamylation altered the effects of atorvastatin on survival. Baseline C-Alb significantly correlated with serum cardiac stress markers troponin T and N-terminal pro-B-type-natriuretic peptide, and was associated with history of heart failure and arrhythmia. C-Alb was strongly associated with 1-year adjusted risk of CV mortality, sudden cardiac death and the 4-year risk of death from congestive heart failure (Hazard Ratios of 3.06, 3.78 and 4.64, respectively), but not with myocardial infarction or stroke. Patients with low C-Alb, treated with atorvastatin, experienced a significant improvement in their 4-year survival (Hazard Ratio 0.692). High C-Alb levels are associated with ongoing cardiac damage, risk of congestive heart failure and sudden cardiac death. Thus, carbamylation and uremic cardiomyopathy are associated in patients with diabetes mellitus and kidney disease. Additionally, statins were specifically beneficial to hemodialysis patients with low C-Alb.

Sudden cardiac death in end stage renal disease: unlocking the mystery

Sudden cardiac death (SCD) is a major cause of concern in end stage renal disease (ESRD), contributing to 70% of cardiovascular mortality and 27% of all-cause mortality in dialysis patients. Yet its mechanisms and pathogenesis remain largely obscure. This review discusses the potential reasons for an exaggerated risk of SCD in ESRD populations taking into account recent studies and registry data and additionally explores the reasons for the reported recent decline in SCD. The types of arrhythmias typical of the hemodialysis population are yet to be fully characterised and in this paper, we introduce an ongoing implantable loop recorder (ILR) based study in hemodialysis patients--CRASH ILR (Cardio Renal Arrhythmia Study in Haemodialysis patients using Implantable Loop Recorders). The findings of this study will hopefully guide the design and implementation of larger ILR based studies before undertaking larger scale interventional therapeutic trials in this high risk population.