Hemodynamic and pathophysiological characteristics of intradialytic blood pressure elevation in patients with end-stage renal disease

The prevalence and risk of mortality associated with intradialytic hypertension among patients with end-stage kidney disease on haemodialysis: A systematic review and meta-analysis

INTRODUCTION

Intradialytic hypertension (IDHTN) is a common but less frequently recognised complication of haemodialysis. However, it is associated with increased overall mortality in patients on haemodialysis. This systematic review and meta-analysis aimed to determine the prevalence of IDHTN and associated mortality risk in the global haemodialysis population.

METHOD

A systematic search of PubMed and EMBASE was undertaken to identify articles with relevant data published between 1990 and 2023. The pooled prevalence of IDHTN in the global haemodialysis population was determined using the DerSimonian-Laird random-effects meta-analysis. The pooled hazards ratio for mortality in patients with IDHTN was also computed from the studies that reported mortality among haemodialysis patients with IDHTN. The study protocol was registered with PROSPERO (CRD42023388278).

RESULTS

Thirty-two articles from 17 countries were included, with a pooled population of 127,080 hemodialysis patients (median age 55.1 years, 38.2% females). Most studies had medium methodological quality (53.1%, n = 17). The overall pooled prevalence of IDHTN was 26.6% [(95% CI 20.2-33.4%), n = 27 studies, I2 = 99.3%, p<0.001 for heterogeneity], with significant differences depending on the definition used. The pooled proportion of haemodialysis sessions with IDHTN was 19.9% [(95% 12.5-28.6%, n = 8 studies, I2 = 99.3%, p<0.001 for heterogeneity)] with significant differences across the different definition criteria. The p-value for the Begg test was 0.85. The median pre-dialysis blood pressure was not significantly associated with IDHTN. The pooled hazard ratio for mortality was 1.37 (95% CI 1.09-1.65), n = 5 studies, I2 = 13.7%, and p-value for heterogeneity = 0.33.

CONCLUSION

The prevalence of IDHTN is high and varies widely according to the definition used. A consensus definition of IDHTN is needed to promote uniformity in research and management. The increased mortality risk forecasted by IDHTN highlights the need for optimal blood pressure control in patients on hemodialysis.

Added value of clinical prediction rules for bacteremia in hemodialysis patients: An external validation study

Introduction

Having developed a clinical prediction rule (CPR) for bacteremia among hemodialysis (HD) outpatients (BAC-HD score), we performed external validation.

Materials & methods

Data were collected on maintenance HD patients at two Japanese tertiary-care hospitals from January 2013 to December 2015. We enrolled 429 consecutive patients (aged ≥ 18 y) on maintenance HD who had had two sets of blood cultures drawn on admission to assess for bacteremia. We validated the predictive ability of the CPR using two validation cohorts. Index tests were the BAC-HD score and a CPR developed by Shapiro et al. The outcome was bacteremia, based on the results of the admission blood cultures. For added value, we also measured changes in the area under the receiver operating characteristic curve (AUC) using logistic regression and Net Reclassification Improvement (NRI), in which each CPR was added to the basic model.

Results

In Validation cohort 1 (360 subjects), compared to a Model 1 (Basic Model) AUC of 0.69 (95% confidence interval [95% CI]: 0.59–0.80), the AUC of Model 2 (Basic model + BAC-HD score) and Model 3 (Basic model + Shapiro’s score) increased to 0.8 (95% CI: 0.71–0.88) and 0.73 (95% CI: 0.63–0.83), respectively. In validation cohort 2 (96 subjects), compared to a Model 1 AUC of 0.81 (95% CI: 0.68–0.94), the AUCs of Model 2 and Model 3 increased to 0.83 (95% CI: 0.72–0.95) and 0.85 (95% CI: 0.76–0.94), respectively. NRIs on addition of the BAC-HD score and Shapiro’s score were 0.3 and 0.06 in Validation cohort 1, and 0.27 and 0.13, respectively, in Validation cohort 2.

Conclusion

Either the BAC-HD score or Shapiro’s score may improve the ability to diagnose bacteremia in HD patients. Reclassification was better with the BAC-HD score.

The effect of an L/N-type calcium channel blocker on intradialytic blood pressure in intradialytic hypertensive patients

BACKGROUND

Intradialytic hypertension (HTN), which is one of the poor prognostic markers in patients undergoing hemodialysis, may be associated with sympathetic overactivity. The L/N-type calcium channel blocker, cilnidipine, has been reported to suppress sympathetic nerves activity in vivo. Therefore, we hypothesized that cilnidipine could attenuate intradialytic systolic blood pressure (SBP) elevation.

METHODS

Fifty-one patients on chronic hemodialysis who had intradialytic-HTN (SBP elevation ≥10 mmHg during hemodialysis) and no fluid overload were prospectively randomized into two groups: control and cilnidipine groups. Cilnidipine group patients took cilnidipine (10 mg/day) for 12 weeks. The primary endpoint was the change in the intradialytic SBP elevation before and after the 12-week intervention.

RESULTS

Before the intervention, no differences were observed in age, sex or pre-dialytic SBP (148.5 ± 12.9 vs. 148.3 ± 19.3 mmHg) between the two groups. Intradialytic SBP elevation was unchanged in the control group. Cilnidipine significantly lowered the post-dialytic SBP with an attenuation of the intradialytic SBP elevation from 12.0 ± 15.4 mmHg to 4.8 ± 10.1 mmHg. However, the observed difference in the intradialytic SBP elevation by cilnidipine did not reach statistical significance (group×time interaction effect p = 0.25). Cathecolamine levels were unaffected by the intervention in both groups.

CONCLUSION

Cilnidipine lowers both the pre- and post-dialytic SBP and might attenuate intradialytic SBP elevation. Therefore, cilnidipine may be effective in lowering SBP during HD in patients with intradialytic-HTN.

Blood Pressure of Maintenance Hemodialysis Patients in the Dalmatian Region of Croatia: Differences between Hospital and Out-of-Hospital Dialysis Centers

AIMS

This study was aimed at comparing the incidence of arterial hypertension and blood pressure (BP) variance in hospital and out-of-hospital hemodialysis (HD) patients during HD sessions.

METHODS

A cross-sectional study was conducted for 1 week at all the HD centers in Dalmatia, Croatia. The pre-, intra-, and post-dialysis BP values were collected for 3 consecutive HD sessions per patient.

RESULTS

Of the 399 subjects, 73.9% were hypertensives, who showed higher interdialytic weight gain compared to the normotensives (2.58 vs. 2.40). Hospital and out-of-hospital HD patients received identical antihypertensive therapies, except that beta blockers were more frequently administered to out-of-hospital HD patients. Higher pre-, intra-, and post-dialysis BP values were recorded in patients at out-of-hospital HD centers.

CONCLUSION

The differences in BP variability and antihypertensive therapies administered to hospital HD patients as compared to out-of-hospital HD patients may reflect differing approaches by the nephrologists at these centers.

The cardiothoracic ratio and all-cause and cardiovascular disease mortality in patients undergoing maintenance hemodialysis: results of the MBD-5D study

BACKGROUND

The cardiothoracic ratio (CTR) is a non-invasive left ventricular hypertrophy index. However, whether CTR associates with cardiovascular disease (CVD) and mortality in hemodialysis (HD) populations is unclear.

METHODS

Using a Mineral and Bone disorder Outcomes Study for Japanese CKD Stage 5D Patients (MBD-5D Study) subcohort, 2266 prevalent HD patients (age 62.8 years, female 38.0%, HD duration 9.4 years) with secondary hyperparathyroidism (SHPT) whose baseline CTR had been recorded were selected. We evaluated associations between CTR and all-cause death, CVD death, or composite events in HD patients.

RESULTS

CTR was associated significantly with various background and laboratory characteristics. All-cause death, CVD-related death, and composite events increased across the CTR quartiles (Q). Adjusted hazard risk (HR) for all-cause death was 1.4 (95% confidential interval, 0.9-2.1) in Q2, 1.9 (1.3-2.9) in Q3, and 2.6 (1.7-4.0) in Q4, respectively (Q1 as a reference). The corresponding adjusted HR for CVD-related death was 1.8 (0.8-4.2), 3.1 (1.4-6.8), and 3.5 (1.6-7.9), and that for composite outcome was 1.2 (1.0-1.6), 1.7 (1.3-2.2), and 1.8 (1.5-2.3), respectively. Exploratory analysis revealed that there were relationships between CTR and age, sex, body mass index, comorbidity of CVD, dialysis duration and intact parathyroid hormone, phosphorus, hemoglobin, and usage of phosphate binder [corrected].

CONCLUSION

CTR correlated with all-cause death, CVD death, and composite events in HD patients with SHPT.