Measures of wave intensity as a non-invasive surrogate for cardiac function predicts mortality in haemodialysis patients

Background

Risk prediction in haemodialysis (HD) patients is challenging due to the impact of the dialysis regime on the patient's volume status and the complex interplay with cardiac function, comorbidities and hypertension. Cardiac function as a key predictor of cardiovascular (CV) mortality in HD patients is challenging to assess in daily routine. Thus the aim of this study was to investigate the association of a novel, non-invasive relative index of systolic function with mortality and to assess its interplay with volume removal.

Methods

A total of 558 (373 male/185 female) HD patients with a median age of 66 years were included in this analysis. They underwent 24-hour ambulatory blood pressure monitoring, including wave intensity analysis [i.e. S:D ratio (SDR)]. All-cause and CV mortality served as endpoints and multivariate proportional hazards models were used for risk prediction. Intradialytic changes were analysed in tertiles according to ultrafiltration volume. During a follow-up of 37.8 months, 193 patients died (92 due to CV reasons).

Results

The SDR was significantly associated with all-cause {univariate hazard ratio [HR] 1.36 [95% confidence interval (CI) 1.20-1.54], P < .001} and CV [univariate HR 1.41 (95% CI 1.20-1.67), P < .001] mortality. The associations remained significant in multivariate analysis accounting for possible confounders. Changes in the SDR from pre-/early- to post-dialytic averages were significantly different for the three ultrafiltration volume groups.

Conclusion

This study provides well-powered evidence for the independent association of a novel index of systolic function with mortality. Furthermore, it revealed a significant association between intradialytic changes of the measure and intradialytic volume removal.

Accuracy of 24 h ambulatory blood pressure recordings for diagnosing high 44 h blood pressure in hemodialysis: a diagnostic test study

Hypertension is highly prevalent in hemodialysis patients. Ambulatory-BP-monitoring(ABPM) during the 44 h interdialytic interval is recommended for hypertension diagnosis and management in these subjects. This study assessed the diagnostic accuracy of fixed 24 h ABPM recordings with 44 h BP in hemodialysis patients. 242 Greek hemodialysis patients that underwent valid 48 h ABPM(Mobil-O-Graph NG device) were included in the analysis. We used 44 h BP as reference method and tested the accuracy of the following BP metrics: 1st 24 h without HD period (20 h-1st), 1st 24 h including HD period (24 h-1st) and 2nd 24 h(24 h-2nd). All studied metrics showed strong correlations with 44 h SBP/DBP (20 h-1st: r = 0.973/0.978, 24 h-1st: r = 0.964/0.972 and 24 h-2nd: r = 0.978/0.977, respectively). In Bland-Altman analysis, small between-method differences (-1.70, -1.19 and +1.45 mmHg) with good 95% limits-of agreement([-10.83 to 7.43], [-11.12 to 8.74] and [-6.33 to 9.23] mmHg, respectively) for 20 h-1st, 24 h-1st and 24 h-2nd SBP were observed. The sensitivity/specificity and κ-statistic for diagnosing 44 h SBP ≥ 130 mmHg were high for 20 h-1st SBP(87.2%/96.0%, κ-statistic = 0.817), 24 h-1st SBP(88.7%/96.0%, κ-statistic = 0.833) and 24 h-2nd SBP (95.0%/88.1%, κ-statistic = 0.837). Similar observations were made for DBP. In ROC-analyses, all studied BP metrics showed excellent performance with high Area-Under-the- Curve values (20 h-1st: 0.983/0.992; 24 h-1st: 0.984/0.987 and 24 h-2nd: 0.982/0.989 for SBP/DBP respectively). Fixed 24 h ABPM recordings during either the first or the second day of interdialytic interval have high accuracy and strong agreement with 44 h BP in hemodialysis patients. Thus, ABPM recordings of either the first or the second interdialytic day could be used for hypertension diagnosis and management in these subjects.

Kidney transplantation and kidney donation do not affect short-term blood pressure variability

PURPOSE

Blood pressure variability (BPV) is an independent cardiovascular risk factor in CKD. Kidney transplantation (KTx) is associated with improved BP levels for kidney transplant recipient (KTRs), without evoking significant changes in donors. The aim of this study was to assess the short- and mid-time effects of KTx and donation on short-term BPV in KTRs and their respective living kidney donors.

MATERIALS AND METHODS

Forty KTRs and their respective donors were evaluated with 24-h ABPM (Mobil-O-Graph-NG) at baseline (1 month before), 3-months and 12-months after KTx. Standard-deviation (SD), weighted-SD (wSD), coefficient-of-variation (CV), average-real-variability (ARV) and variability independent of mean (VIM) for SBP/DBP were calculated with validated formulas.

RESULTS

All 24-h systolic and diastolic BPV indexes studied did not change significantly from baseline to 3-month (SBP-wSD: 12.8 ± 3.0 vs 13.2 ± 3.4 mmHg, p = 0.608; SBP-ARV: 10.3 ± 2.4 vs 10.8 ± 2.6 mmHg, p = 0.463) and 12-month evaluation (SBP-wSD 12.8 ± 3.0 vs 12.1 ± 2.8; p = 0.424 and SBP-ARV: 10.3 ± 2.4 vs 10.2 ± 2.5; p = 0.615) after kidney transplantation in the KTRs.In kidney donors, all 24-h systolic BPV indices displayed a trend towards higher values at 3 months compared to baseline, but without reaching statistical significance (SBP-wSD: 12.2 ± 2.8 vs 13.6 ± 4.2 mmHg, p = 0.107 and SBP-ARV: 10.1 ± 2.1 vs 11.2 ± 3.1 mmHg, p = 0.099), the levels of 24-h systolic SBP indices at 12-months were almost identical to baseline values. 24-h diastolic BPV indices at 3-month and 12-month evaluation were similar to baseline.

CONCLUSION

Short-term BPV did not change significantly 3 and 12 months after kidney transplantation/donation neither in KTRs nor in living kidney donors. Longitudinal studies examining associations of BPV with adverse outcomes in these individuals are needed.

Association of Intradialytic Hypertension with Future Cardiovascular Events and Mortality in Hemodialysis Patients: Effects of Ambulatory Blood Pressure

INTRODUCTION

Intradialytic hypertension (IDHTN) is associated with increased risk of adverse outcomes. Patients with IDHTN have higher 44-h blood pressure (BP) than patients without this condition. Whether the excess risk in these patients is due to the BP rise during dialysis per se or on elevated 44-h BP or other comorbid conditions is uncertain. This study evaluated the association of IDHTN with cardiovascular events and mortality and the influence of ambulatory BP and other cardiovascular risk factors on these associations.

METHODS

242 hemodialysis patients with valid 48-h ABPM (Mobil-O-Graph-NG) were followed for a median of 45.7 months. IDHTN was defined as: systolic BP (SBP) rise ≥10 mm Hg from pre- to post-dialysis and post-dialysis SBP ≥150 mm Hg. The primary endpoint was all-cause mortality; the secondary endpoint was a composite of cardiovascular death, nonfatal myocardial infarction, nonfatal stroke, resuscitation after cardiac arrest, heart failure hospitalization, coronary or peripheral revascularization.

RESULTS

Cumulative freedom from both the primary and secondary endpoint was significantly lower for IDHTN patients (logrank-p = 0.048 and 0.022, respectively), corresponding to higher risks for all-cause mortality (hazard ratio (HR) = 1.566; 95% confidence interval (CI) [1.001, 2.450]) and the composite cardiovascular outcome (HR = 1.675; 95% CI [1.071, 2.620]) in these individuals. However, the observed associations lost statistical significance after adjustment for 44-h SBP (HR = 1.529; 95% CI [0.952, 2.457] and HR = 1.388; 95% CI [0.866, 2.225], respectively). In the final model after additional adjustment for 44-h SBP, interdialytic weight gain, age, history of coronary artery disease, heart failure, diabetes, and 44-h pulse wave velocity, the association of IDHTN with the outcomes was also not significant and the respective HRs were 1.377 (95% CI [0.836, 2.268]) and 1.451 (95% CI [0.891, 2.364]).

CONCLUSIONS

IDHTN patients had higher risk for mortality and cardiovascular outcomes but this risk is at least partly confounded by the elevated BP levels during the interdialytic period.

Intra-dialytic blood pressure variability is a greater predictor of cardiovascular events in hemodialysis patients

BACKGROUND

Short-term and long-term blood pressure variability (BPV) in hemodialysis (HD) population are risk factors of cardiovascular diseases (CVD) and all-cause mortality. There is no full consensus on the best BPV metric. We compared the prognostic role of intra-dialytic and visit-to-visit BPV metrics for CVD morbidity and all-cause mortality in HD patients.

METHODS

A retrospective cohort of 120 patients on HD was followed up for 44 months. Systolic blood pressure (SBP) and baseline characteristics were collected for 3 months. We calculated intra-dialytic and visit-to-visit BPV metrics, including standard deviation (SD), coefficient of variation (CV), variability independent of the mean (VIM), average real variability (ARV) and residual. The primary outcomes were CVD events and all-cause mortality.

RESULTS

In Cox regression analysis, both intra-dialytic and visit-to-visit BPV metrics were associated with increased CVD events (intra-dialytic CV: HR 1.70, 95% CI 1.28-2.27, p < 0.01; visit-to-visit CV: HR 1.55, 95% CI 1.12-2.16, p < 0.01), but not associated with increased all-cause mortality (intra-dialytic CV: HR 1.32, 95% CI 0.99-1.76, p = 0.06; visit-to-visit CV: HR 1.22, 95% CI 0.91-1.63, p = 0.18). Overall, intra-dialytic BPV showed greater prognostic ability than visit-to-visit BPV for both CVD event (AUC of intra-dialytic BPV and visit-to-visit BPV metrics respectively: SD 0.686, 0.606; CV 0.672, 0.425; VIM 0.677, 0.581; ARV 0.684, 0.618; residual 0.652, 0.586) and all-cause mortality (SD 0.671, 0.608; CV 0.662, 0.575; VIM 0.669, 0.581; ARV 0.529, 0.588; residual 0.651, 0.602).

CONCLUSION

Compared to visit-to-visit BPV, intra-dialytic BPV is a greater predictor of CVD event in HD patients. No obvious priority was found among various BPV metrics.

Association between Intra- and Extra-Cellular Water Ratio Imbalance and Natriuretic Peptides in Patients Undergoing Hemodialysis

Natriuretic peptides are associated with malnutrition and volume overload. Over-hydration cannot simply be explained by excess extracellular water in patients undergoing hemodialysis. We assessed the relationship between the extracellular and intracellular water (ECW/ICW) ratio, N-terminal pro-B-type natriuretic peptide (NT-proBNP), human atrial natriuretic peptide (hANP), and echocardiographic findings. Body composition was examined by segmental multi-frequency bioelectrical impedance analysis in 368 patients undergoing maintenance dialysis (261 men and 107 women; mean age, 65 ± 12 years). Patients with higher ECW/ICW ratio quartiles tended to be older, were on dialysis longer, and had higher post-dialysis blood pressure and lower body mass index, ultrafiltration volume, serum albumin, blood urea nitrogen, and creatinine levels (p < 0.05). The ECW/ICW ratio significantly increased with decreasing ICW, but not with ECW. Patients with a higher ECW/ICW ratio and lower percent fat had significantly higher natriuretic peptide levels. After adjusting for covariates, the ECW/ICW ratio remained an independent associated factor for natriuretic peptides (β = 0.34, p < 0.001 for NT-proBNP and β = 0.40, p < 0.001 for hANP) and the left ventricular mass index (β = 0.20, p = 0.002). The ICW-ECW volume imbalance regulated by decreased cell mass may explain the reserve capacity for fluid accumulation in patients undergoing hemodialysis.

Peridialytic and intradialytic blood pressure metrics are not valid estimates of 44-h ambulatory blood pressure in patients with intradialytic hypertension

PURPOSE

In contrast to peridialytic blood pressure (BP), intradialytic and home BP measurements are accurate metrics of ambulatory BP load in hemodialysis patients. This study assessed the agreement of peridialytic, intradialytic, and scheduled interdialytic recordings with 44-h BP in a distinct hemodialysis population, patients with intradialytic hypertension (IDH).

METHODS

This study included 45 IDH patients with valid 48-h ABPM and 197 without IDH. With 44-h BP used as reference method, we tested the accuracy of the following BP metrics: Pre- and post-dialysis, mean and median intradialytic, mean intradialytic plus pre/post-dialysis, and scheduled interdialytic BP (out-of-dialysis day: mean of 8:00am/8:00 pm readings).

RESULTS

In IDH patients, peridialytic and intradialytic BP metrics showed at best moderate correlations, while averaged interdialytic SBP/DBP exhibited strong correlation (r = 0.882/r = 0.855) with 44-h SBP/DBP. Bland-Altman plots showed large between-method-difference for peri- and intradialytic-BP, but only + 0.7 mmHg between-method difference and good 95% limits of agreement for averaged interdialytic SBP. The sensitivity/specificity and κ-statistic for diagnosing 44-h SBP ≥ 130 mmHg were low for pre-dialysis (72.5/40.0%, κ-statistic = 0.074) and post-dialysis (90.0/0.0%, κ-statistic = - 0.110), mean intradialytic (85.0/40.0%, κ-statistic = 0.198), median intradialytic (85.0/60.0%, κ-statistic = 0.333), and intradialytic plus pre/post-dialysis SBP (85.0/20.0%, κ-statistic = 0.043). Averaged interdialytic SBP showed high sensitivity/specificity (97.5/80.0%) and strong agreement (κ-statistic = 0.775). In ROC analyses, scheduled interdialytic SBP/DBP had the highest AUC (0.967/0.951), sensitivity (90.0/88.0%), and specificity (100.0/90.0%).

CONCLUSION

In IDH patients, only averaged scheduled interdialytic but not pre- and post-dialysis, nor intradialytic BP recordings show reasonable agreement with ABPM. Interdialytic BP recordings only could be used for hypertension diagnosis and management in these subjects.

Sex-related short-term blood pressure variability differences in kidney transplant recipients

OBJECTIVE

Kidney transplant recipients (KTRs) display higher cardiovascular morbidity and mortality than the general population. Increased short-term blood pressure variability (BPV) is associated with a higher risk of adverse cardiovascular outcomes in chronic kidney disease (CKD). The aim of this study is to investigate sex differences in short-term BPV in KTRs.

METHODS

In total, 136 male and 69 female KTRs with valid 24 h ambulatory blood pressure monitoring were included in this analysis. Systolic and diastolic BPV indices [SD, weighted SD (wSD), coefficient of variation (CV), average real variability (ARV) and variability independent of the mean (VIM)] were calculated with validated formulas for the 24 h, daytime and nighttime periods.

RESULTS

Age, time from transplantation surgery and history of major comorbidities did not differ between men and women. During the 24-h period, systolic BPV indices did not differ between men and women (SBP-ARV: 9.4 ± 2.2 vs. 9.9 ± 2.5; P = 0.212). During the daytime period, SBP-CV and SBP-VIM were significantly higher in females compared with male participants (SBP-CV: 9.9 ± 2.4 vs. 11 ± 3.1%; P = 0.022 and SBP-VIM: 12.6 ± 3.0 vs 14.2 ± 3.9; P = 0.008); daytime SBP-SD and SBP-ARV, and all studied indexes during nighttime did not differ between groups. No significant between-group differences in 24 h and daytime diastolic BPV indices were detected. Nighttime DBP-CV was marginally higher in men (12.0 ± 3.6 vs. 11.4 ± 4.0; P = 0.053); the rest nighttime diastolic BPV indices measured were also nonsignificantly higher in men.

CONCLUSION

In conclusion, 24-h systolic and diastolic BPV parameters did not differ between male and female KTRs, but short-term BPV over the respective day- and nighttime periods showed different trends in men and women. Further studies are needed to examine possible differences in long-term BPV in KTRs.

Ambulatory central BP and arterial stiffness in patients with and without intradialytic hypertension

BACKGROUND

Increased arterial stiffness is suggested to be involved in the pathogenesis of intradialytic-hypertension (IDH). Ambulatory pulse-wave-velocity (PWV) is an independent predictor for all-cause-mortality in haemodialysis and its prognostic power is better than office PWV. This is the first study examining ambulatory central blood pressure (BP) and arterial stiffness parameters in patients with and without IDH.

METHODS

This study examined 45 patients with IDH (SBP rise ≥10 mmHg from pre- to post-dialysis and post-dialysis SBP ≥150 mmHg) in comparison with 197 patients without IDH. All participants underwent 48-h ABPM with Mobil-O-Graph-NG; parameters of central haemodynamics, wave reflection and PWV were estimated.

RESULTS

Age, dialysis vintage and interdialytic weight gain did not differ between-groups. IDH patients had higher 48-h cSBP (131.7 ± 16.2 vs. 119.2 ± 15.2 mmHg, p < 0.001), 48-h cDBP (86.7 ± 12.7 vs. 79.6 ± 11.5 mmHg, p < 0.001) and 48-h cPP (45.5 ± 10.4 vs. 39.8 ± 10.0 mmHg, p = 0.001) compared to patients without IDH. Similarly, during day- and nighttime periods, cSBP/cDBP and cPP levels were higher in IDH-patients compared to non-IDH. Forty-eight-hour augmentation pressure and index, but not AIx(75) were higher in IDH patients; 48-h PWV (10.0 ± 2.0 vs. 9.2 ± 2.1 m/s, p = 0.017) was significantly higher in patients with IDH. The two study groups displayed different trajectories in central BP and PWV over the course of the recording; IDH patients had steadily high values of the above variables during the 2 days of the interdialytic-interval, whereas non-IDH patients showed a gradual elevation, with significant increases from the 1st to 2nd 24 h.

CONCLUSIONS

IDH patients have significantly higher levels of ambulatory central BP and arterial stiffness parameters and a different course over the 48-h period compared with non-IDH patients. Increased arterial stiffness could be a prominent factor associated with the high burden of cardiovascular disease in this population.

Short-term blood pressure variability and outcomes in non-dialysis chronic kidney disease

Background

Blood pressure variability (BPV) is associated with cardiovascular and all-cause mortality, and has been demonstrated in dialysis patients, but has been poorly studied and remains controversial in non-dialysis chronic kidney disease (CKD) patients. We investigated the effect of short-term BPV on prognosis in this population.

Methods

A total of 245 stage 1–4 CKD patients with 24-h ambulatory blood pressure recordings were recruited. BPV was evaluated by standard deviation, coefficient of variation, and variation independent of the mean, respectively. All subjects were followed up to the composite end-point event or until January 15, 2020. Patients were divided into two groups based on 24-h median variation independent of the mean, and demographics, laboratory indicators and echocardiogram results were compared. Logistic regression was used to analyze the risk factors for increased BPV. Multivariate Cox regression and Kaplan-Meier survival analysis were used to explore the relationship between BPV and renal prognosis and major cardiovascular events.

Results

The mean age was 42.07 ± 12.66 years, with 141 males (57.55%). Multivariate Logistic regression analysis showed that high BMI (OR 1.110, P = 0.017), hyperkalemia (OR 2.227, P = 0.040), increased left ventricular end-diastolic diameter (OR 1.103, P = 0.010) and hypertension (OR 2.525, P = 0.002) were independent risk factors for high BPV. Kaplan-Meier survival analysis showed that renal and cardiovascular outcomes were better in the low BPV group than in the high BPV group (P = 0.006; P = 0.002). After adjusting for age, sex and traditional kidney related risk factors, BPV were not independently associated with renal outcomes. High BPV (HR 4.662, P = 0.017) was the main independent risk factor for major cardiovascular events in CKD.

Conclusions

In non-dialysis CKD, short-term BPV was associated with major cardiovascular disease but not renal progression. BMI, hypertension, potassium balance, and left ventricular end-diastolic diameter influenced short-term BPV.

Sex differences in ambulatory blood pressure levels, control and phenotypes of hypertension in hemodialysis patients

BACKGROUND AND AIMS

Ambulatory blood pressure (BP) control is worse in men than women with chronic kidney disease or kidney transplantation. So far, no study investigated possible sex differences in the prevalence, control, and phenotypes of BP according to predialysis and 48-h ambulatory blood pressure monitoring (ABPM) in hemodialysis patients. Further, no study has evaluated the diagnostic accuracy of predialysis BP in male and female hemodialysis patients.

METHOD

One hundred and twenty-nine male and 91 female hemodialysis patients that underwent 48-h ABPM were included in this analysis. Hypertension was defined as: (1) predialysis SBP ≥140 or DBP ≥90 mmHg or use of antihypertensive agents, (2) 48-h SBP ≥130 or DBP ≥80 mmHg or use of antihypertensive agents.

RESULTS

Predialysis SBP did not differ between groups, while DBP was marginally higher in men. 48-h SBP (137.2 ± 17.4 vs. 132.2 ± 19.2 mmHg, P  = 0.045), DBP (81.9 ± 12.1 vs. 75.9 ± 11.7 mmHg, P  < 0.001) and daytime SBP/DBP were higher in men. The prevalence of hypertension was not different between groups with the use of predialysis BP or 48-h ABPM (92.2% vs. 89%, P  = 0.411). However, concordant lack of control was more frequent in men than women (65.3% vs. 49.4%, P  = 0.023). The prevalence of white-coat and masked hypertension did not differ between groups; the misclassification rate with the use of predialysis BP was marginally higher in women. In both sexes, predialysis BP showed low accuracy and poor agreement with ABPM for diagnosing ambulatory hypertension [area-under-the-curve in receiver-operating-curve analyses (SBP/DBP): men, 0.681/0.802, women: 0.586/0.707].

CONCLUSION

Ambulatory BP levels are higher in male than female hemodialysis patients. Although hypertension prevalence is similar between sexes, men have worse rates of control. The diagnostic accuracy of predialysis BP was equally poor in men and women.

Effect of patient gender on short-term blood pressure variability in hemodialysis patients

Increased blood pressure variability (BPV) is strongly associated with cardiovascular events in end-stage kidney disease patients. Male hemodialysis patients present higher cardiovascular risk compared with females. The aim of this study is to investigate sex differences in short-term BPV in hemodialysis patients. 129 male and 91 female hemodialysis patients that underwent 48-h ABPM were included in this analysis. Standard deviation (SD), weighted SD (wSD), coefficient of variation (CV), and average real variability (ARV) of SBP and DBP were calculated with validated formulas. Age, dialysis vintage and history of major comorbidities did not differ between men and women. 48-h SBP/DBP (137.2 ± 17.4/81.9 ± 12.1 mmHg vs 132.2 ± 19.2/75.9 ± 11.7 mmHg, p = 0.045/<0.001) was significantly higher in men than women. During the 48-h period, all systolic BPV indices were similar between men and women (48-h SBP-ARV: 12.0 ± 2.9 vs 12.1 ± 3.2 mmHg, p = 0.683); 48-h DBP-SD, DBP-wSD and DBP-ARV (9.1 ± 1.6 vs 8.4 ± 1.8 mmHg, p = 0.005) were higher in men. In conclusion, short-term diastolic BPV indices are higher in male than female hemodialysis patients. Increased BPV may impact on the higher incidence of cardiovascular events observed in male hemodialysis patients.

Ambulatory blood pressure trajectories and blood pressure variability in kidney transplant recipients: a comparative study against chronic kidney disease patients

Background

Methods

Results

Conclusion

Long-term predialysis blood pressure variability and outcomes in hemodialysis patients

Blood pressure variability (BPV) is significantly associated with cardiovascular diseases (CVD) and mortality in hemodialysis patients. However, the relationship between blood pressure and CVD in hemodialysis patients is complex and affected by many factors. The present study aimed to assess the association of long‐term predialysis BPV with all‐cause mortality and major adverse cardiovascular events (MACE). One thousand seven hundred twenty‐seven patients receiving maintenance hemodialysis were recruited in nine hemodialysis centers. Predialysis BPV was assessed over 1‐year intervals. Outcomes included all‐cause mortality and MACE during follow‐up periods. The mean age of the final cohort was 59 years, of which 57% were males. Greater predialysis systolic BPV was associated with an increased risk of all‐cause mortality (adjusted hazard ratio, 1.101; 95% confidence intervals 1.064–1.140) and MACE (adjusted hazard ratio, 1.091; 95% confidence intervals 1.059–1.125). Results were similar when systolic BPV was stratified by baseline systolic blood pressure. In conclusion, greater predialysis BPV among hemodialysis patients was associated with all‐cause mortality and MACE. Strategies to reduce blood pressure variability might be beneficial for hemodialysis patients.

Pre-dialytic Systolic Blood Pressure is an Independent Predictor of Intradialytic Hypertension

BACKGROUND: Since endothelial dysfunction and activation of renin-angiotensin aldosterone system are the primary mechanism of intradialytic hypertension (IDHT), the assessment of pre dialytic blood pressure might provide an important information for the prediction of IDHT. OBJECTIVES: To assess the association between pre dialytic blood pressure and the risk of IDHT. METHODS: We conducted a cross-sectional study in Universitas Muhammadiyah Malang Hospital. The inclusion criteria were all hemodialysis patients aged more than 18 years, and the exclusion criteria were patients with hemodialysis duration of less than three months, patients with poor compliance to consume antihypertensive drugs, and hemodynamically unstable. The predictor variable was pre dialytic systolic blood pressure and the outcome was the incidence of IDHT. The association between pre dialytic blood pressure and the risk of IDHT was assessed using multiple logistic regression. RESULTS: A total of 36 patients with IDHT and 60 patients without IDHT was enrolled in our study. Our study identified that pre dialytic systolic blood pressure was associated with the risk of IDHT, with mean difference was 10.90 mmHg between patients with IDHT and without IDHT. Our study confirmed that the levels of pre dialytic systolic blood pressure 135 mmHg was the optimal cut off, and we found that patients with pre dialytic systolic blood pressure ≥ 135 mmHg had 4.60-fold to develop IDHT compared to patients with pre dialytic systolic blood pressure < 135 mmHg. CONCLUSION: Our study reveals that pre dialytic systolic blood pressure is an important predictor of IDHT.

Association of peridialytic, intradialytic, scheduled interdialytic and ambulatory BP recordings with cardiovascular events in hemodialysis patients

BACKGROUND

Ambulatory-BP-monitoring (ABPM) is recommended for hypertension diagnosis and management in hemodialysis patients due to its strong association with outcomes. Intradialytic and scheduled interdialytic BP recordings show agreement with ambulatory BP. This study assesses in parallel the association of pre-dialysis, intradialytic, scheduled interdialytic and ambulatory BP recordings with cardiovascular events.

METHODS

We prospectively followed 242 hemodialysis patients with valid 48-h ABPMs for a median of 45.7 months to examine the association of pre-dialysis, intradialytic, intradialytic plus pre/post-dialysis readings, scheduled interdialytic BP, and 44-h ambulatory BP with outcomes. The primary end-point was a composite one, composed of cardiovascular death, non-fatal myocardial infarction, non-fatal stroke, resuscitation after cardiac arrest, hospitalization for heart failure, coronary revascularization procedure or peripheral revascularization procedure.

RESULTS

Cumulative freedom from the primary end-point was significantly lower with increasing 44-h SBP (group 1, < 120 mmHg, 64.2%; group 2, ≥ 120 to < 130 mmHg 60.4%, group 3, ≥ 130 to < 140 mmHg 45.3%; group 4, ≥ 140 mmHg 45.5%; logrank-p = 0.016). Similar were the results for intradialytic (logrank-p = 0.039), intradialytic plus pre/post-dialysis (logrank-p = 0.044), and scheduled interdialytic SBP (logrank-p = 0.030), but not for pre-dialysis SBP (logrank-p = 0.570). Considering group 1 as the reference group, the hazard ratios of the primary end-point showed a gradual increase with higher BP levels with all BP metrics, except pre-dialysis SBP. This pattern was confirmed in adjusted analyses. An inverse association of DBP levels with outcomes was shown with all BP metrics, which was no longer evident in adjusted analyses.

CONCLUSIONS

Averaged intradialytic and scheduled home BP measurements (but not pre-dialysis readings) display similar prognostic associations with 44-h ambulatory BP in hemodialysis patients and represent valid metrics for hypertension management in these individuals.

Ambulatory blood pressure trajectories and blood pressure variability in kidney transplant recipients: a comparative study against hemodialysis patients

Background

Hypertension is the most prevalent cardiovascular risk factor in kidney transplant recipients (KTRs). Preliminary data suggest similar ambulatory blood pressure (BP) levels in KTRs and haemodialysis (HD) patients. This is the first study comparing the full ambulatory BP profile and short-term BP variability (BPV) in KTRs versus HD patients.

Methods

A total of 204 KTRs were matched (2:1 ratio) with 102 HD patients for age and gender. BP levels, BP trajectories and BPV indices over a 24-h ambulatory BP monitoring (ABPM) in KTRs were compared against both the first and second 24-h periods of a standard 48-h ABPM in HD patients. To evaluate the effect of renal replacement treatment and time on ambulatory BP levels, a two-way ANOVA for repeated measurements was performed.

Results

KTRs had significantly lower systolic blood pressure (SBP) and pulse-pressure (PP) levels compared with HD patients during all periods studied (24-h SBP: KTR: 126.5 ± 12.1 mmHg; HD first 24 h: 132.0 ± 18.1 mmHg; P = 0.006; second 24 h: 134.3 ± 17.7 mmHg; P < 0.001); no significant differences were noted for diastolic blood pressure levels with the exception of the second nighttime. Repeated measurements ANOVA showed a significant effect of renal replacement therapy modality and time on ambulatory SBP levels during all periods studied, and a significant interaction between them; the greatest between-group difference in BP (KTRs–HD in mmHg) was observed at the end of the second 24 h [–13.9 mmHg (95% confidence interval –21.5 to –6.2); P < 0.001]. Ambulatory systolic and diastolic BPV indices were significantly lower in KTRs than in HD patients during all periods studied (24-h SBP average real variability: KTRs: 9.6 ± 2.3 mmHg; HD first 24 h: 10.3 ± 3.0 mmHg; P = 0.032; second 24 h: 11.5 ± 3.0 mmHg; P < 0.001). No differences were noted in dipping pattern between the two groups.

Conclusions

SBP and PP levels and trajectories, and BPV were significantly lower in KTRs compared with age- and gender-matched HD patients during all periods studied. These findings suggest a more favourable ambulatory BP profile in KTRs, in contrast to previous observations.

Blood Pressure Variability and Prognosis in Hemodialysis Patients: A Systematic Review and Meta-Analysis

Background

The prognostic value of blood pressure variability (BPV) in patients receiving hemodialysis is inconclusive. In this study, we aimed to assess the association between BPV and clinical outcomes in the hemodialysis population.

Methods

Pubmed/Medline, EMBASE, Ovid, the Cochrane Library, and the Web of Science databases were searched for relevant articles published until April 1, 2020. Studies on the association between BPV and prognosis in patients receiving hemodialysis were included.

Results

A total of 14 studies (37,976 patients) were included in the analysis. In patients receiving hemodialysis, systolic BPV was associated with higher all-cause (hazard ratio [HR]: 1.13; 95% confidence interval [CI]: 1.07-1.19; p < 0.001) and cardiovascular (HR: 1.16; 95% CI: 1.10-1.22; p < 0.001) mortality. In the stratified analysis of systolic BPV, interdialytic systolic BPV, rather than 44-h ambulatory systolic BPV or intradialytic systolic BPV, was identified to be related to both all-cause (HR: 1.11; 95% CI: 1.05-1.17; p = 0.001) and cardiovascular (HR: 1.14; 95% CI: 1.06-1.22; p < 0.001) mortality. Among the different BPV metrics, the coefficient of variation of systolic blood pressure was a predictor of both all-cause (p = 0.01) and cardiovascular (p = 0.002) mortality. Although diastolic BPV was associated with all-cause mortality (HR: 1.09; 95% CI: 1.01-1.17; p = 0.02) in patients receiving hemodialysis, it failed to predict cardiovascular mortality (HR: 0.86; 95% CI: 0.52-1.42; p = 0.56).

Conclusions

This meta-analysis revealed that, in patients receiving hemodialysis, interdialytic systolic BPV was associated with both increased all-cause and cardiovascular mortality. Furthermore, the coefficient of variation of systolic blood pressure was identified as a potentially promising metric of BPV in predicting all-cause and cardiovascular mortality. The use of 44-h ambulatory systolic BPV, intradialytic systolic BPV, and metrics of diastolic BPV in the prognosis of the hemodialysis population require further investigation (PROSPERO registry number: CRD42019139215).

An Analysis of Frequency of Continuous Blood Pressure Variation and Haemodynamic Responses during Haemodialysis

BACKGROUND

Higher beat-to-beat blood pressure (BP) variation during haemodialysis (HD) has been shown to be associated with elevated cardiac damage markers and white matter ischaemic changes in the brain suggesting relevance to end-organ perfusion. We aimed to characterize individual patterns of BP variation and associated haemodynamic responses to HD.

METHODS

Fifty participants underwent continuous non-invasive haemodynamic monitoring during HD and BP variation were assessed using extrema point (EP) frequency analysis. Participants were divided into those with a greater proportion of low frequency (LF, n = 21) and high frequency (HF, n = 22) of BP variation. Clinical and haemodynamic data were compared between groups.

RESULTS

Median EP frequencies for mean arterial pressure (MAP) of mid-week HD sessions were 0.54 Hz (interquartile range 0.18) and correlated with dialysis vintage (r = 0.32, p = 0.039), NT pro-BNP levels (r = 0.32, p = 0.038), and average real variability (ARV) of systolic BP (r = 0.33, p = 0.029), ARV of diastolic BP (r = 0.46, p = 0.002), and ARV of MAP (r = 0.57, p < 0.001). In the LF group, MAP positively correlated with cardiac power index (CPI) in each hour of dialysis, but not with total peripheral resistance index (TPRI). In contrast, in the HF group, MAP correlated with TPRI in each hour of dialysis but only with CPI in the first hour.

CONCLUSIONS

EP frequency analysis of continuous BP monitoring during dialysis allows assessment of BP variation and categorization of individuals into low- or high-frequency groups, which were characterized by different haemodynamic responses to dialysis. This may assist in improved individualization of dialysis therapy.

Dapagliflozin Does Not Affect Short-Term Blood Pressure Variability in Patients With Type 2 Diabetes Mellitus

BACKGROUND

Increased blood pressure variability (BPV) is associated with increased cardiovascular and all-cause mortality in patients with type-2 diabetes mellitus (T2DM). Sodium-glucose co-transporter 2 (SGLT-2) inhibitors decrease the incidence of cardiovascular events, renal events, and death in this population. This study aimed to evaluate the effect of dapagliflozin on short-term BPV in patients with T2DM.

METHODS

This is a secondary analysis of a double-blind, randomized, placebo-controlled trial in 85 patients with T2DM. Subjects were randomized to dapagliflozin 10 mg/day or placebo for 12 weeks. All participants underwent 24-hour ambulatory blood pressure (BP) monitoring with Mobil-O-Graph-NG device at baseline and study-end. SD, weighted SD (wSD), coefficient of variation, average real variability (ARV), and variation independent of mean were calculated for the 24-hour, daytime and nighttime periods.

RESULTS

Dapagliflozin reduced 24-hour brachial BP compared with placebo. From baseline to study-end 24-hour brachial BPV indexes did not change with dapagliflozin (SBP-ARV: 11.51 ± 3.45 vs. 11.05 ± 3.35; P = 0.326, SBP-wSD: 13.59 ± 3.60 vs. 13.48 ± 3.33; P = 0.811) or placebo (SBP-ARV: 11.47 ± 3.63 vs. 11.05 ± 3.00; P = 0.388, SBP-wSD: 13.85 ± 4.38 vs. 13.97 ± 3.87; P = 0.308). Similarly, no significant changes in BPV indexes for daytime and nighttime were observed in any group. At study-end, no between-group differences were observed for any BPV index. Deltas (Δ) of all indexes during follow-up were minimal and not different between groups (SBP-wSD: dapagliflozin: -0.11 ± 3.05 vs. placebo: 0.12 ± 4.20; P = 0.227).

CONCLUSIONS

This study is the first to evaluate the effects of an SGLT-2 inhibitor on short-term BPV in T2DM, showing no effect of dapagliflozin on all BPV indexes studied.

CLINICAL TRIALS REGISTRATION

Trial Number NCT02887677.

Accuracy of Peridialytic, Intradialytic, and Scheduled Interdialytic Recordings in Detecting Elevated Ambulatory Blood Pressure in Hemodialysis Patients

RATIONALE & OBJECTIVE

Current recommendations suggest the use of ambulatory blood pressure monitoring (ABPM) as the gold standard for hypertension diagnosis and management in hemodialysis patients. This study assesses the accuracy of peridialytic, intradialytic, and scheduled interdialytic recordings in detecting abnormally elevated 44-hour interdialytic blood pressure (BP).

STUDY DESIGN

Diagnostic test study.

SETTINGS & PARTICIPANTS

242 Greek hemodialysis patients who successfully underwent ABPM.

TESTS COMPARED

Ambulatory BP was used as the reference method to evaluate the accuracy of the following BP metrics: predialysis and postdialysis BP, intradialytic BP, intradialytic plus pre/postdialysis BP, and scheduled interdialytic BP (on an off-dialysis day at 8:00 am, 8:00 pm, and their average).

OUTCOME

44-hour ambulatory systolic BP/diastolic BP (SBP/DBP) ≥ 130/80 mm Hg.

RESULTS

The 44-hour SBP/DBP levels differed significantly from predialysis and postdialysis BP but showed no or minor differences compared with the other BP metrics. Bland-Altman plots showed an absence of systematic bias for all metrics but large between-method difference and wider 95% limits of agreement for predialysis and postdialysis BP compared with intradialytic, intradialytic plus pre/postdialysis, and averaged scheduled interdialytic BP. The sensitivity/specificity and κ-statistic for diagnosing 44-hour SBP ≥ 130 mm Hg were low for predialysis (86.5%/38.6%, κ-statistic = 0.27) and postdialysis BP (63.1%/73.3%, κ-statistic = 0.35), but better for intradialytic BP (77.3%/76.2%, κ-statistic = 0.53), intradialytic plus pre/postdialysis BP (76.6%/72.3%, κ-statistic = 0.49), and scheduled interdialytic BP (87.9%/77.2%, κ-statistic = 0.66). In receiver operating characteristic (ROC) analyses, the areas under the curve (AUC) of predialysis SBP (AUC = 0.723) and postdialysis SBP (AUC = 0.746) were significantly lower than that of intradialytic SBP (AUC = 0.850), intradialytic plus pre/postdialysis SBP (AUC = 0.850), and scheduled interdialytic SBP (AUC = 0.917) (z test, P < 0.001 for all pairwise comparisons). Similar observations were made for DBP.

LIMITATIONS

Typical home BP data were not obtained, and no assessment was obtained of the reproducibility of the examined metrics over time.

CONCLUSIONS

Intradialytic, intradialytic plus pre/postdialysis, and scheduled interdialytic BP measurements were more accurate in detecting elevated 44-hour BP than predialysis and postdialysis BP. Averaged intradialytic BP recordings or scheduled readings at the off-dialysis day appear to be promising approaches to the diagnosis of elevated BP in hemodialysis.

Volume overload in hemodialysis: diagnosis, cardiovascular consequences, and management

Volume overload in haemodialysis (HD) patients associates with hypertension and cardiac dysfunction and is a major risk factor for all-cause and cardiovascular mortality in this population. The diagnosis of volume excess and estimation of dry weight is based largely on clinical criteria and has a notoriously poor diagnostic accuracy. The search for accurate and objective methods to evaluate dry weight and to diagnose subclinical volume overload has been intensively pursued over the last 3 decades. Most methods have not been tested in appropriate clinical trials and their usefulness in clinical practice remains uncertain, except for bioimpedance spectroscopy and lung ultrasound (US). Bioimpedance spectroscopy is possibly the most widely used method to subjectively quantify fluid distributions over body compartments and produces reliable and reproducible results. Lung US provides reliable estimates of extravascular water in the lung, a critical parameter of the central circulation that in large part reflects the left ventricular end-diastolic pressure. To maximize cardiovascular tolerance, fluid removal in volume-expanded HD patients should be gradual and distributed over a sufficiently long time window. This review summarizes current knowledge about the diagnosis, prognosis and treatment of volume overload in HD patients.

Prognostic importance of long-term SBP variability in high-risk hypertension

OBJECTIVE

In addition to high blood pressure variability (BPV), low BPV was associated with adverse cardiovascular prognosis in selected high-risk patients. We explored this issue in the Systolic Blood Pressure Intervention Trial (SPRINT) using a nonlinear approach with BPV as a continuous variable.

METHODS

Long-term systolic BPV (SBPV) (coefficient of variation, CoV %) was calculated on quarterly visits until a fatal/nonfatal cardiovascular event or all-cause mortality, excluding titration period and patients with missing visits. We used Cox proportional hazard models with penalized smoothing splines to shape the risk of outcomes against the continuum of SBPV (independent variable). Adjusted hazard ratios (aHR, 95% CI) were calculated using the reference range derived from the nonlinear model. Sensitivity analysis based on propensity score matching (PSM) was performed.

RESULTS

The association of SBPV with fatal/nonfatal cardiovascular events was J-shaped, whereas that with all-cause mortality was linear. After multivariate adjustment, however, the only significant associations remained that of low SBPV (CoV <5%) with cardiovascular events (hazard ratio 1.85, 95% CI 1.24-2.75, P = 0.003), and of high SBPV (CoV >10%) with the composite of cardiovascular events and all-cause mortality (hazard ratio 1.35, 95% CI 1.02-1.80; P = 0.037). Low SBPV was associated with ischemic heart disease (hazard ratio 2.76, 95% CI 1.55-4.91; P < 0.001). There was a significant U-shaped association of SBPV with cardiovascular events in the PSM cohort.

CONCLUSION

Nonlinear modeling indicates that low and high long-term SBPV have prognostic relevance in high-risk hypertensive individuals from SPRINT. Randomized trials are needed to test these findings and their potential therapeutic implications.

Heart Failure and Atrial Fibrillation Modify the Associations of Nocturnal Blood Pressure Dipping Pattern With Mortality in Hemodialysis Patients

Heart failure (HF), hypertension, and abnormal nocturnal blood pressure dipping are highly prevalent in hemodialysis patients. Atrial fibrillation (AF) and HF might be important mediators for the association of abnormal dipping patterns with worse prognosis. Thus, the aim of this study is to investigate the association of dipping with mortality in hemodialysis patients and to assess the influence of AF and HF. In total, 525 hemodialysis patients underwent 24-hour ambulatory blood pressure monitoring. All-cause and cardiovascular mortality served as end points. Patients were categorized according to their systolic dipping pattern (dipper, nondipper, and reverse dipper). Cox regression analysis was performed to determine the association between dipping pattern and study end points with dipping as reference. Subgroup analysis was performed for patients with and without AF or HF. In total, 185 patients with AF or HF and 340 patients without AF or HF were included. During a median follow-up of 37.8 months, 177 patients died; 81 from cardiovascular causes. Nondipping and reverse dipping were significantly associated with all-cause mortality in the whole cohort (nondipper: hazard ratio, 1.95 [1.22-3.14]; P=0.006; reverse dipper: hazard ratio, 2.31 [1.42-3.76]; P<0.001) and in patients without AF or HF (nondipper: hazard ratio, 2.78 [1.16-6.66]; P=0.02; reverse dipper: hazard ratio, 4.48 [1.87-10.71]; P<0.001) but not in patients with AF or HF. For cardiovascular mortality, associations were again significant in patients without AF or HF and in the whole cohort. The observed associations remained significant after adjustment for possible confounders. This study provides well-powered evidence for the association between abnormal dipping patterns and mortality in hemodialysis patients and suggests that HF or AF modifies this association.

Comparative Efficacy and Safety of BP-Lowering Pharmacotherapy in Patients Undergoing Maintenance Dialysis: A Network Meta-Analysis of Randomized, Controlled Trials

BACKGROUND AND OBJECTIVES

Elevated BP is an important risk factor for cardiovascular disease, with a prevalence of over 80% in patients undergoing maintenance dialysis. We assessed the comparative BP-lowering efficacy and the safety of BP-lowering drugs in patients undergoing maintenance dialysis.

DESIGN, SETTINGS, PARTICIPANTS, & MEASUREMENTS

We performed a frequentist random effects network meta-analysis of randomized, controlled trials evaluating BP-lowering agents in adult patients undergoing maintenance dialysis. Electronic databases (CENTRAL, MEDLINE, and Embase) were systematically searched (up to August 2018) for relevant trials. The main outcome was systolic BP reduction.

RESULTS

Forty trials (4283 participants) met our inclusion criteria. Angiotensin-converting enzyme inhibitors, β-blockers, calcium-channel blockers, and aldosterone antagonists lowered systolic BP to a greater extent than placebo, with effect sizes ranging from -10.8 mm Hg (95% confidence interval, -14.8 to -6.7 mm Hg) for the aldosterone antagonists to -4.3 mm Hg (95% confidence interval, -7.2 to -1.5 mm Hg) for angiotensin-converting enzyme inhibitors. Aldosterone antagonists and β-blockers were superior to angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, calcium-channel blockers, and renin inhibitors at lowering systolic BP. Compared with angiotensin-converting enzyme inhibitors, aldosterone antagonists and β-blockers lowered systolic BP by 6.4 mm Hg (95% confidence interval, -11.4 to -1.4 mm Hg) and 4.4 mm Hg (95% confidence interval, -7.4 to -1.3 mm Hg), respectively. Systolic BP reduction was not different with angiotensin receptor blockers, α-blockers, and calcium-channel blockers compared with angiotensin-converting enzyme inhibitors. Renin inhibitors were less effective. Angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, and aldosterone antagonists incurred risks of drug discontinuation due to adverse events and hypotension.

CONCLUSIONS

BP-lowering agents significantly reduced systolic BP in patients undergoing maintenance dialysis. β-Blockers and aldosterone antagonists may confer larger reductions, although treatment with aldosterone antagonists may be limited by adverse events.

Blood Pressure Variability and Outcomes in End-Stage Renal Disease Patients on Dialysis: A Systematic Review and Meta-Analysis

Objective: Previous studies have suggested that blood pressure variability (BPV) is associated with an increased risk of mortality and cardiovascular events in patients on dialysis. However, the results are inconsistent. A comprehensive literature review was conducted to analyze the association between BPV and outcomes in patients on dialysis. Methods: Articles in Embase, Medline, and Web of Science from the date of inception through January 1, 2020, were identified. The outcomes were all-cause and cardiovascular mortality and cardiovascular events. The risk of bias was assessed using the Newcastle-Ottawa scale tool. Random effects models were used to pool the overall effect sizes. Two reviewers extracted the data independently. Meta-regression and subgroup analyses were performed to explore potential heterogeneity. Results: Fifteen eligible studies were included, and all enrolled hemodialysis recipients only. The overall risk of bias for the included studies was low. A 1-SD increase in systolic BPV was associated with higher risks of all-cause mortality (HR = 1.18; 95% CI 1.11–1.26, I2 = 53.8%), cardiovascular mortality (HR = 1.23; 95% CI 1.10–1.37, I2 = 57.2%), and cardiovascular events (HR = 1.27; 95% CI 1.07–1.51, I2 = 69.3%). Likewise, a 1-SD increase in diastolic BPV was associated with higher HR for all-cause and cardiovascular mortality (HR = 1.14; 95% CI 1.05–1.23, I2 = 0.0%, and HR = 1.14; 95% CI 0.94–1.38, I2 = 0.0%, respectively). Conclusions: A greater BPV is associated with higher risks of cardiovascular and mortality outcomes in patients on hemodialysis. Further research is required to determine whether BPV may be useful either as a marker enabling individualized treatment of cardiovascular risk or as a treatment target in its own right.

Weak within-individual association of blood pressure and pulse wave velocity in hemodialysis is related to adverse outcomes

OBJECTIVES

Hemodialysis patients have premature arterial stiffness, and the relationship between pulse wave velocity (PWV) and blood pressure (BP) may be different than in other hypertensives. Previous studies in such patients showed that when BP decrease is accompanied by PWV decrease the survival is improved. This study examines the prognostic role of the mean BP (MBP)-PWV association for cardiovascular outcomes and all-cause mortality in hemodialysis.

METHODS

A total of 242 hemodialysis patients underwent 48-h ambulatory BP monitoring with Mobil-O-Graph-NG and were followed for 33.17 ± 19.68 months. The within-individual MBP-PWV association (MBP, dependent and PWV independent variable) was evaluated using the β-coefficient value from simple linear regression analysis for each patient. The primary end-point was first occurrence of all-cause death, nonfatal myocardial infarction or nonfatal stroke. Secondary end-points were all-cause mortality, cardiovascular mortality and a combination of cardiovascular events.

RESULTS

Higher quartiles of β-coefficients (indicating strong within-individual association of MBP with PWV) were related to greater cumulative freedom from the primary end-point (50.8, 60.0, 70.0 and 80.3% for quartiles 1-4, respectively; log-rank P = 0.001), better overall survival (60.7, 61.7, 73.3, 86.9%; log-rank P = 0.002) and better cardiovascular survival (78.7, 75.0, 81.7, 91.8% for quartiles 1-4; log-rank P = 0.044). The future risks of the primary end-point, all-cause and cardiovascular mortality and the combined outcome were progressively increasing with lower quartiles of β-coefficients, indicating patients with weak MBP-PWV association (hazard ratios for all-cause mortality 3.395; 95% confidence interval: 1.524-7.563, P = 0.003 for quartile 1 vs. quartile 4).

CONCLUSION

Weaker within-individual MBP-PWV association, based on ABPM recordings, is associated with higher risk of death and cardiovascular events in hemodialysis. These findings support that arterial stiffness insensitive to BP changes is the underlying factor for adverse outcomes in these individuals.

Blood pressure and volume management in dialysis: conclusions from a Kidney Disease: Improving Global Outcomes (KDIGO) Controversies Conference

Blood pressure (BP) and volume control are critical components of dialysis care and have substantial impacts on patient symptoms, quality of life, and cardiovascular complications. Yet, developing consensus best practices for BP and volume control have been challenging, given the absence of objective measures of extracellular volume status and the lack of high-quality evidence for many therapeutic interventions. In February of 2019, Kidney Disease: Improving Global Outcomes (KDIGO) held a Controversies Conference titled Blood Pressure and Volume Management in Dialysis to assess the current state of knowledge related to BP and volume management and identify opportunities to improve clinical and patient-reported outcomes among individuals receiving maintenance dialysis. Four major topics were addressed: BP measurement, BP targets, and pharmacologic management of suboptimal BP; dialysis prescriptions as they relate to BP and volume; extracellular volume assessment and management with a focus on technology-based solutions; and volume-related patient symptoms and experiences. The overarching theme resulting from presentations and discussions was that managing BP and volume in dialysis involves weighing multiple clinical factors and risk considerations as well as patient lifestyle and preferences, all within a narrow therapeutic window for avoiding acute or chronic volume-related complications. Striking this challenging balance requires individualizing the dialysis prescription by incorporating comorbid health conditions, treatment hemodynamic patterns, clinical judgment, and patient preferences into decision-making, all within local resource constraints.

Two-Day ABPM-Derived Indices and Mortality in Hemodialysis Patients

BACKGROUND

Blood pressure (BP) and arterial stiffness are known cardiovascular risk factors in hemodialysis (HD) patients. This study examines the prognostic significance of 44-hour BP circadian rhythm and ambulatory arterial stiffness index (AASI) in this population.

METHODS

A total of 80 HD patients underwent 44-hour ambulatory BP monitoring (ABPM) with a TM-2430 monitor during a standard midweek interdialytic interval and followed up for 4.5 ± 1.7 years. The end point was all-cause mortality.

RESULTS

About 76% of participants were hypertensive (40% uncontrolled), 62% were nondippers, and 23% risers during the first interdialytic day, whereas 73% and 44% in the second day, respectively. During follow-up, 31 patients (40%) died. These showed higher pulse pressure (PP) and AASI44 and AASI of the second interdialytic period. The incidence of all-cause mortality was higher in HD patients with AASI44 > median, i.e. >0.54 (interquartile range = 14) (54% vs. 28%, χ 2 = 5.3, P = 0.021) when compared with those with lower AASI44. Second, but not first-day ABPM-derived parameters, namely nondipping (log-rank χ 2 = 6.10, P = 0.0134) or reverse dipping status (log-rank χ 2 = 5.32, P = 0.210) and arterial stiffness index (log-rank χ 2 = 6.61, P = 0.0101) were significantly related to greater mortality.

CONCLUSIONS

These findings indicate a strong relationship between arterial stiffness and cardiovascular risk and support a wider use of 44-hour ABPM recording for risk stratification in HD patients.

Increased Nighttime Pulse Pressure Variability but Not Ambulatory Blood Pressure Levels Predicts 14-Year All-Cause Mortality in Patients on Hemodialysis

Increased short-term blood pressure (BP) variability is associated with adverse cardiovascular outcomes in patients with hypertension. The present study investigated the long-term prognostic significance of the short-term blood pressure variability in patients on hemodialysis. A total of 149 patients (53.0% male; mean age: 54.5±15.1 years) receiving regular hemodialysis for >6 months were enrolled. They completed a 44-hour (excluding the hemodialysis session) ambulatory BP monitoring and comprehensive hemodynamic assessments, including carotid-femoral pulse wave velocity and pressure waveform decomposition (forward and backward wave amplitude). Blood pressure variability parameters, including average real variability (ARV) of systolic BP, diastolic BP, and pulse pressure (ARVp) during daytime, nighttime, and overall 44 hours were calculated. During a median follow-up of 14 years, 78 deaths (52.4%) were confirmed. In multivariable Cox regression analysis, none of the ambulatory BP parameters were predictive of mortality. In contrast, nighttime ARVp was consistently and significantly associated with all-cause mortality in multivariable Cox models adjusting for age, sex, albumin, hemodialysis treatment adequacy, and 44-hour systolic BP (continuous variable analysis, per 1-SD, hazard ratio=1.348; 95% CI, 1.029-1.767; categorical variable analysis, ≥8.5 versus <8.5 mm Hg; hazard ratio=1.825; 95% CI, 1.074-3.103). Forward wave amplitude and 44-hour systolic BP were identified as the 2 most important determinants of nighttime ARVp. Addition of nighttime ARVp to the base model significantly improved prediction of all-cause mortality (Net reclassification improvement =0.198; P=0.0012). In hemodialysis patients, increased short-term nighttime pulse pressure variability but not ambulatory BP levels were significantly predictive of long-term all-cause mortality.

Lung Ultrasound-Guided Dry-Weight Reduction in Hemodialysis Patients Does Not Affect Short-Term Blood Pressure Variability

BACKGROUND

Increased short-term blood pressure (BP) variability (BPV) in hemodialysis is associated with increased cardiovascular and all-cause mortality. Studies on the impact of BP-lowering interventions on BPV are scarce. This study examined the effect of dry-weight reduction with a lung ultrasound-guided strategy on short-term BPV in hemodialysis patients with hypertension.

METHODS

This is a prespecified analysis of a randomized clinical trial in 71 hemodialysis patients with hypertension, assigned in a 1:1 ratio in the active group, following a strategy for dry-weight reduction guided by pre-hemodialysis lung ultrasound and the control group following standard-of-care treatment. All patients underwent 48-hour ambulatory BP monitoring at baseline and after 8 weeks. BPV was calculated with validated formulas for the 48-hour interval and the 2 daytime and nighttime periods.

RESULTS

Dry-weight changes were -0.71 ± 1.39 in active vs. +0.51 ± 0.98 kg in the control group (P < 0.001), generating a between-group difference of 5.9/3.5 mm Hg (P < 0.05) in 48-hour BP at study end. All brachial BPV indices [SD, weighted SD, coefficient of variation, and average real variability (ARV)] did not change significantly from baseline to study end in the active [systolic blood pressure (SBP)-ARV: 12.58 ± 3.37 vs. 11.91 ± 3.13, P = 0.117; diastolic blood pressure (DBP)-ARV: 9.14 ± 1.47 vs. 8.80 ± 1.96, P = 0.190] or control (SBP-ARV: 11.33 ± 2.76 vs. 11.07 ± 2.51, P = 0.544; DBP-ARV: 8.38 ± 1.50 vs. 8.15 ± 1.49, P = 0.295) group (between-group comparison P = 0.211/0.117). Aortic BPV indices followed a similar pattern. Likewise, no significant changes in BPV indices for the daytime and nighttime periods were noted in both groups during follow-up.

CONCLUSIONS

This study is the first to evaluate the effects of a nonpharmacological intervention on short-term BPV in hemodialysis, showing no effect of dry-weight reduction on BPV, despite BP decrease.

Peritoneal dialysis has optimal intradialytic hemodynamics and preserves residual renal function: Why isn't it better than hemodialysis?

Rates of cardiovascular mortality are disproportionately high in patients with end stage kidney disease receiving dialysis. However, it is now generally accepted that patient survival is broadly equivalent between the two most frequently used forms of dialysis, in-center hemodialysis (HD) and peritoneal dialysis (PD). This equivalent patient survival is notable when considering how specific aspects of HD have been shown to contribute to morbidity and mortality. These include more rapid loss of residual renal function (RRF), HD-induced myocardial and cerebral ischemia, and risk factors associated with the intermittent delivery of HD. Potential mechanisms specific to PD that may drive cardiovascular disease include the metabolic consequences of excessive absorption of glucose and glucose degradation products (GDPs), inadequate volume control, and high rates of hypokalemia. The aim of this review is to compare and contrast the different drivers of adverse outcomes between the dialysis modalities, as greater understanding of this may help in patient-centered decision-making when considering options for renal replacement therapy.