Treating Home Versus Predialysis Blood Pressure Among In-Center Hemodialysis Patients: A Pilot Randomized Trial

RATIONALE & OBJECTIVE

Observational studies have reported a U-shaped association between blood pressure (BP) before a hemodialysis session and death. In contrast, because a linear association between out-of-dialysis-unit BP and death has been reported, home BP may be a better target for treatment. To test the feasibility of this approach, we conducted a pilot trial of treating home versus predialysis BP in hemodialysis patients.

STUDY DESIGN

A 4-month, parallel, randomized, controlled trial.

SETTINGS & PARTICIPANTS

50 prevalent hemodialysis patients in San Francisco and Seattle. Participants were randomly assigned using 1:1 block randomization, stratified by site.

INTERVENTIONS

To target home systolic BP (SBP) of 100-<140 mm Hg versus predialysis SBP of 100-<140mm Hg. Home and predialysis SBPs were ascertained every 2 weeks. Dry weight and BP medications were adjusted to reach the target SBP.

OUTCOMES

Primary outcomes were feasibility, adherence, safety. and tolerability.

RESULTS

50 of 70 (71%) patients who were approached agreed to participate. All enrollees completed the study except for 1 who received a kidney transplant. In the home BP treatment group, adherence to obtaining/reporting home BP was 97.4% (and consistent over the 4 months). There was no increased frequency of high (defined as SBP>200mm Hg; 0.2% vs 0%) or low (defined as<90mm Hg; 1.8% vs 1.2%) predialysis BP readings in the home versus predialysis treatment arms, respectively. However, participants in the home BP arm had higher frequency of fatigue (32% vs 16%).

LIMITATIONS

Small sample size.

CONCLUSIONS

This pilot trial demonstrates feasibility and high adherence to home BP measurement and treatment in hemodialysis patients. Larger trials to test the long-term feasibility, efficacy, and safety of home BP treatment in hemodialysis patients should be conducted.

FUNDERS

National Institutes of Health, Satellite Healthcare, and Northwest Kidney Centers.

TRIAL REGISTRATION

Registered at ClinicalTrials.gov with study number NCT03459807.

Modern peptide biomarkers and echocardiography in cardiac healthy haemodialysis patients

BACKGROUND

In this prospective study, we aimed to assess the haemodynamic changes before and after haemodialysis (HD) in cardiac healthy subjects on chronic HD by imaging methods and endocrine markers of fluid balance.

METHODS

Mid-regional pro-atrial natriuretic peptide (MR-proANP), N-terminal prohormone of brain natriuretic peptide (NT-proBNP), vasopressin (AVP) and copeptin (CT-proAVP), metanephrines and normetanephrines, renin and aldosterone, standard transthoracic echocardiography and diameter of vena cava inferior (VCID) were performed in 20 patients with end stage renal disease (CKD5D) before and after HD and were stratified in residual excretion (RE, less or more 0.5 l) and ultrafiltration rate (UF, less or more 2 l).

RESULTS

Copeptin was significantly higher in patients before HD. Copeptin was inversely correlated with haemodialysis treatment adequacy (KT/v), RE and UF, but was not significantly influenced by age, gender and body mass index (BMI). MR-proANP was significantly reduced by haemodialysis by 27% and was inversely correlated with KT/v, but there was a significant influence by UF, RE, age, gender and BMI. NT-proBNP was significantly higher in patients before HD and was not influenced by RE and UF. Renin, aldosterone, metanephrines and normetanephrines did not demonstrate significant differences. Echocardiographic parameters and VCID were significantly correlated with RE, UF and copeptin.

CONCLUSION

Modern biomarkers will provide cardiovascular risk assessment, but elimination (UF), RE and other factors may influence the serum concentrations, e.g. in patients with renal impairment. The interpretation will be limited by altered reference ranges, and will be restricted to individual courses combined with clinical and echocardiographic data.

Association of NTproBNP and cTnI with outpatient sudden cardiac death in hemodialysis patients: the Choices for Healthy Outcomes in Caring for ESRD (CHOICE) study

BACKGROUND

Sudden cardiac death (SCD) is the most common etiology of death in hemodialysis patients but not much is known about its risk factors. The goal of our study was to determine the association and risk prediction of SCD by serum N-terminal prohormone of brain natriuretic peptide (NTproBNP) troponin I (cTnI) in hemodialysis patients.

METHODS

We measured NTproBNP and cTnI in 503 hemodialysis patients of a national prospective cohort study. We determined their association with SCD using Cox regression, adjusting for demographics, co-morbidities, and clinical factors and risk prediction using C-statistic and Net Reclassification Improvement (NRI).

RESULTS

Patients' mean age was 58 years and 54 % were male. During follow-up (median 3.5 years), there were 75 outpatient SCD events. In unadjusted and fully-adjusted models, NTproBNP had a significant association with the risk of SCD. Analyzed as a continuous variable, the risk of SCD increased 27 % with each 2-fold increase in NTproBNP (HR, 1.27 per doubling; 95 % CI, 1.13-1.43; p < 0.001). In categorical models, the risk of SCD was 3-fold higher in the highest tertile of NTproBNP (>7,350 pg/mL) compared with the lowest tertile (<1,710 pg/mL; HR for the highest tertile, 3.03; 95 % CI, 1.56-5.89; p = 0.001). Higher cTnI showed a trend towards increased risk of SCD in fully adjusted models, but was not statistically significant (HR, 1.17 per doubling; 95 % CI, 0.98-1.40; p = 0.08). Sensitivity analyses using competing risk models showed similar results. Improvement in risk prediction by adding cardiac biomarkers to conventional risk factors was greater with NTproBNP (C-statistic for 3-year risk: 0.810; 95 % CI, 0.757 to 0.864; and continuous NRI: 0.270; 95 % CI, 0.046 to 0.495) than with cTnI.

CONCLUSIONS

NTproBNP is associated with the risk of SCD in hemodialysis patients. Further research is needed to determine if biomarkers measurement can guide SCD risk prevention strategies in dialysis patients.

Hemodialysis-associated cardiomyopathy: a newly defined disease entity

Cardiovascular disease is the most common cause of the greatly elevated rates of mortality characteristic of patients undergoing maintenance hemodialysis. This article is an attempt to describe the complex and evolving features of cardiac disease routinely encountered in HD patients. Furthermore, by trying to appreciate the pathophysiological drivers, and the crucial interaction with the HD treatment itself, this article seeks to define cardiac disease in this setting (HD-associated cardiomyopathy) as a unique and complex entity. By understanding the phenotype and basis of HD-associated cardiomyopathy, we can develop an evolved understanding of the dominant processes involved in its development and offer up dialysis-based interventions specifically designed to mitigate the cumulative ischemic insults consequent to conventional HD treatment. This article explores the justification of this approach and recent evidence of its efficacy.

Determinants of hemodialysis-induced segmental wall motion abnormalities

Patients who demonstrate worsening of cardiac wall motion (WM) during hemodialysis have higher 1-year mortality. We sought to identify risk factors for dialysis-induced WM abnormalities. Additionally, we examined the effects of hemodialysis on other parameters of cardiac function. Forty patients underwent echocardiography directly before dialysis and during the last hour of dialysis (79 dialysis sessions). Candidate predictors for intradialytic worsening of WM included age, a history of heart failure (HF) or coronary artery disease, changes in blood pressure or heart rate, high sensitivity cardiac troponin T and N-terminal brain natriuretic peptide. Among 40 patients, WM worsened segmentally in eight patients (20%), worsened globally in one patient (3%), and improved segmentally in four patients (10%). Diastolic function worsened in 44% of patients, and left ventricular ejection fraction was largely unchanged during dialysis. The case of globally worsened WM occurred in the setting of intradialytic hypertension in a patient without HF. Surprisingly, history of coronary artery disease, hemodynamics, and serologic factors were not associated with worsened segmental WM during dialysis. After adjustment for history of coronary artery disease and other cardiac risk factors, patients with a history of HF had a threefold higher risk of worsening segmental WM during dialysis (RR 3.1, 95% CI [1.1, 9], p = 0.04). In conclusion, patients with a history of clinical HF were at higher risk of intradialytic worsening of segmental WM. Further studies are needed to determine the mechanism of this association and whether cardioprotective medications could ameliorate this adverse cardiac effect of hemodialysis.