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

Background

Methods

Results

Conclusion

Peripheral endothelial and microvascular damage in liver cirrhosis: a systematic review and meta-analysis

OBJECTIVE

This is the first systematic review and meta-analysis of studies using any available functional method to examine differences in peripheral endothelial function between cirrhotic and non-cirrhotic individuals.

METHODS

Literature search involved PubMed, Web-of-Science and Scopus databases, as well as grey literature sources. We included studies in adult subjects evaluating endothelial function with any semi-invasive or non-invasive functional method in patients with and without liver cirrhosis.

RESULTS

From 3378 records initially retrieved, 15 studies with a total of 570 participants were included in the final quantitative meta-analysis. In 6 studies examining endothelial function with flow-mediated-dilatation no differences between patients with cirrhosis and controls were evident (WMD: 1.33, 95%CI [-2.87, 5.53], I² =97%, p<0.00001). Among studies assessing differences in endothelial-dependent or endothelial-independent vasodilation with venous-occlusion-plethysmography, there were no significant differences between the two groups. When pooling all studies together, regardless of the technique used, no significant difference in endothelial function between cirrhotic patients and controls was observed(SMD: 0.79, 95%CI[-0.04, 1.63], I2=94%, p<0.00001).

CONCLUSIONS

No differences in peripheral endothelial function assessed with semi-invasive or non-invasive functional methods exist between cirrhotic and non-cirrhotic subjects. The increasing co-existence of cardiovascular risk factors leading to impaired vascular reactivity in cirrhotic patients may partly explain these findings.

MO081: Ambulatory Blood Pressure Trajectories and Blood Pressure Variability in Kidney Transplant Recipients: A Comparative Study Against Chronic Kidney Disease Patients

BACKGROUND AND AIMS

Hypertension is a major cardiovascular risk factor in both kidney transplant recipients (KTRs) and patients with chronic kidney disease (CKD). Ambulatory blood pressure monitoring (ABPM) is considered the gold standard method for hypertension management in these subjects. This is the first study evaluating in comparison the full ambulatory BP profile and short-term BP variability (BPV) in KTRs versus CKD patients without kidney replacement therapy.

METHOD

93 KTRs were matched with 93 CKD patients for age, sex and eGFR. All participants underwent 24 h ABPM; mean ambulatory BP levels, BP trajectories and BPV indices [standard deviation (SD), weighted-SD and average real variability] were compared between the two groups.

RESULTS

There were no significant between-group differences in 24-h SBP/DBP (KTRs:126.9 ± 13.1/79.1 ± 7.9 versus CKD:128.1 ± 11.2/77.9 ± 8.1 mmHg,  P = 0.522/0.293), daytime SBP/DBP and nighttime SBP; nighttime DBP was slightly higher in KTRs (KTRs:76.5 ± 8.8 versus CKD:73.8 ± 8.8 mmHg, P = 0.040). For both ambulatory SBP/DBP, repeated-measurements-ANOVA showed a significant effect of time (SBP: F = [19, 3002]=11.735, P &lt; 0.001, partial η2 = 0.069) but not of KTR/CKD status (SBP: F = [1, 158] = 0.668, P = 0.415, partial η2 = 0.004). Ambulatory systolic/diastolic BPV indices were not different between KTRs and CKD patients, except for 24-h DBP-SD that was slightly higher in the latter (KTRs: 10.2 ± 2.2 versus CKD: 10.9 ± 2.6 mmHg, P = 0.041). No differences were noted in dipping pattern between the two groups.

CONCLUSION

Mean ambulatory BP levels, BP trajectories and short-term BPV indices are not significantly different between KTRs and CKD patients, suggesting that KTRs have a similar ambulatory BP profile compared with CKD patients without kidney replacement therapy.

MO743: The Influence of Ambulatory Blood Pressure on the Associations of Intradialytic Hypertension with Future Cardiovascular Events and Mortality in Haemodialysis Patients

BACKGROUND AND AIMS

Patients with intradialytic hypertension (IDH) have higher mean 44-h ambulatory blood pressure (BP) levels than patients without the phenomenon. IDH is associated with an increased risk of cardiovascular and all-cause mortality. Whether the excess risk for mortality in patients with IDH depends on the BP rise during dialysis per se or on elevated 44-h ambulatory BP is not known. This is the first study evaluating the association of IDH with cardiovascular events and all-cause mortality before and after adjustment for ambulatory BP and other cardiovascular risk factors.

METHOD

A total of 242 haemodialysis patients underwent 48-h ABPM with Mobil-O-Graph-NG and were followed for a median of 45.7 months. IDH was defined as: SBP rise ≥ 10 mmHg from pre- to post-dialysis and post-dialysis SBP ≥ 150 mmHg. The primary end-point was all-cause mortality; the secondary endpoint was a composite of cardiovascular death, non-fatal myocardial infarction, non-fatal stroke, resuscitation after cardiac arrest, hospitalization for heart failure, coronary or peripheral revascularization procedures.

RESULTS

During follow-up, a total of 122 patients died; 69 due to cardiovascular causes. Cumulative freedom from both the primary and secondary endpoints was significantly lower for patients with IDH (log rank-P = 0.048/0.022, respectively). The risk for all-cause mortality was significantly higher for patients with IDH [HR = 1.566, 95% confidence interval (95% CI) (1.001, 2.450)]; similarly, the risk for the combined cardiovascular endpoint was higher for these individuals [HR = 1.675, 95% CI (1.071, 2.620)]. The observed associations attenuated after adjustment for 44-h SBP [all-cause mortality: HR = 1.529, 95% CI (0.952, 2.457)] and combined cardiovascular endpoint: HR = 1.388 95% CI (0.866, 2.225). After additional adjustment for age, interdialytic weight gain, dialysis vintage, 44-h pulse wave velocity, history of coronary artery disease, diabetes mellitus and heart failure the respective HRs were 1.409 [95% CI (0.851, 2.332)] and 1.435 [95% CI (0.879, 2.343)].

CONCLUSION

Patients with IDH presented higher risk for death and cardiovascular outcomes. Sustained high BP levels during the 44-h interdialytic period and not only intradialytic BP rise per se may be participating in the excess risk of this condition.

MO088: Peridialytic and Intradialytic Blood Pressure Measurements are Not Valid Estimates of 44-Hour Ambulatory Blood Pressure in Patients With Intradialytic Hypertension

BACKGROUND AND AIMS

In contrast with pre- and post-dialysis 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 interdialytic BP in a distinct hemodialysis population, patients with intradialytic-hypertension (IDH).

METHOD

45 patients with IDH (defined as: SBP rise ≥ 10 mmHg from pre- to post-dialysis and post-dialysis SBP ≥ 150 mmHg) with valid 48-h ABPM and 197 without IDH were included in this analysis. With 44-h BP used as reference method, we tested the accuracy of the following BP metrics: Pre- and post-dialysis, intradialytic, intradialytic plus pre/post-dialysis readings and scheduled interdialytic BP (out-of-dialysis day: readings at 8:00 am, 8:00 pm or their average).

RESULTS

In patients with IDH, peri-dialytic 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), intradialytic (85.0%/40.0%, κ-statistic = 0.198) and intradialytic plus pre/post-dialysis SBP (85.0%/20.0%, κ-statistic = 0.043). Averaged-interdialytic-SBP showed high values of sensitivity/specificity (97.5%/80.0%) and strong agreement (κ-statistic = 0.775). In ROC-analyses, the peri- and intradialytic BP metrics showed bad performance with low Area-Under-the-Curve values; scheduled interdialytic SBP/DBP had the largest AUC (0.967/0.951), along with the highest sensitivity(90.0%/88.0%) and specificity(100.0%/90.0%) for detecting elevated 44-h BP.

CONCLUSION

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

MO089: Comparison of Ambulatory Central Hemodynamics and Arterial Stiffness in Hemodialysis Patients With And Without Intradialytic Hypertension

BACKGROUND AND AIMS

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 hemodialysis patients and its prognostic power is better than office PWV. This is the first study comparing ambulatory central blood pressure (BP) and arterial stiffness parameters between patients with and without IDH.

METHOD

This study examined 45 patients with IDH (defined as: SBP rise ≥ 10 mmHg from pre- to post-dialysis and post-dialysis SBP ≥ 150 mmHg) in comparison 197 without IDH. All participants underwent 48-h ABPM with the Mobil-O-Graph-NG device; parameters of central hemodynamics [central systolic (cSBP) and diastolic BP (cDBP), pulse pressure (PP)], wave reflection [augmentation index (AIx) and pressure (AP)] and PWV were estimated.

RESULTS

Age, dialysis vintage, interdialytic weight gain and prevalence of major comorbidities did not differ between the two study groups. Patients with IDH had higher 44-h cSBP (131.6 ± 16.7 versus 119.3 ± 15.6, P &lt; 0.001), 44-h cDBP (86.4 ± 12.8 versus 79.3 ± 11.7, P &lt; 0.001) and 44-h cPP (45.7 ± 10.7 versus 40.3 ± 10.3, P = 0.002) levels compared with patients without IDH. Similarly, during day- and nighttime periods, cSBP/cDBP and cPP levels were higher in IDH patients compared with non-IDH. 44-h augmentation pressure and index, but not AIx(75) were higher in patients with IDH than those without IDH. 44-h PWV (10.0 ± 2.0 vs. 9.2 ± 2.1 m/s, P = 0.020) was significantly higher in patients with IDH.

CONCLUSION

Patients with IDH have higher ambulatory central BP and increased arterial stiffness, as indicated by higher ambulatory cPP and PWV. Increased arterial stiffness could be a prominent factor associated with the high burden of cardiovascular disease in this population.

MO086: Sex Differences in Ambulatory Blood Pressure Trajectories and Blood Pressure Variability in Hemodialysis Patients

BACKGROUND AND AIMS

Ambulatory blood pressure (BP) control is worse in men than in women with chronic kidney disease (CKD), and this may partially explain the faster CKD progression in men. The aim of this study is to investigate possible sex-differences in ambulatory BP levels, BP trajectories and BP variability (BPV) in hemodialysis patients.

METHOD

129 male and 91 female hemodialysis patients that underwent 48-h ABPM with Mobil-O-Graph-NG were included in this analysis. Ambulatory BP levels over the 2-day interdialytic interval (including two daytime and two nighttime periods) were recorded. We calculated the standard deviation (SD), weighted SD (wSD), coefficient of variation (CV) and average real variability (ARV) of BP with validated formulas.

RESULTS

Age, dialysis vintage, antihypertensive treatment and history of major comorbidities did not differ between men and women. Pre-dialysis SBP levels did not differ between men and women (145.1 ± 22.7 versus 145.9 ± 25.7 mmHg, P = 0.808), but DBP was marginally higher in men (87.6 ± 14.0 versus 84.0 ± 13.7 mmHg, P =0.055). About 48-h SBP/DBP (137.2 ± 17.4/81.9 ± 12.1 mmHg versus 132.2 ± 19.2/75.9 ± 11.7 mmHg, P = 0.045/&lt;0.001) as well as DBP during the first and SBP/DBP during the second 24-h period were significantly higher in men than in women. Similarly, daytime SBP/DBP was significantly higher in men (138.3 ± 17.5/83.2 ± 12.3 mmHg versus 131.9 ± 19.4/76.4 ± 11.5 mmHg, P = 0.011/&lt;0.001). No significant between-group differences were detected for nighttime SBP. All SBP variability indices were similar between men and women; DBP-SD, DBP-wSD and DBP-ARV were higher in men (44-h DBP-ARV 9.4 ± 1.8 versus 8.6 ± 1.9, P = 0.002). No significant differences were revealed in the dipping pattern between men and women.

CONCLUSION

Ambulatory BP levels and trajectories, as well as DBP variability indices are higher in men than women hemodialysis patients. This worse ambulatory BP profile in male compared to female patients may impact on the incidence of cardiovascular events.

MO685: Brain Oxygenation Assessed by Near-Infrared Spectroscopy During a Mental Task and a Mild Physical Stress in Hemodialysis and Peritoneal Dialysis

BACKGROUND AND AIMS

Cognitive impairment is highly prevalent in end-stage kidney disease (ESKD) individuals. Brain oxygenation is a parameter that plays major role in cognitive function. This study aimed to examine for the first time changes in brain oxygenation during a mental and a mild physical task in hemodialysis (HD) and peritoneal dialysis (PD) patients.

METHOD

A total of 63 ESKD patients (≥18 years old) were enrolled in this cross-sectional study. Patients were allocated in two groups according to dialysis modality (n = 29 HD and n = 34 PD). All participants underwent a mental (countdown from 100 to 0 by 7, performed twice) and a mild physical task (a 3-min intermittent handgrip exercise at 35% of maximal handgrip strength). Changes in brain oxygenation [oxy—(O2Hb), deoxy—(HHb) and total—(tHb) hemoglobin] during the two tasks were continuously recorded via near-infrared spectroscopy (NIRS, Artinis).

RESULTS

Age, sex and dialysis vintage did not differ between the two groups. The average response in brain oxygenation during the mental task (O2Hb change from rest: 1.51 ± 1.68 versus 1.60 ± 1.82 μmol, in HD and PD, respectively, P = 0.841), as well as the duration needed for task completion (191.53 ± 124.27 versus 200.19 ± 118.84 s, P = 0.781) were similar between groups. Furthermore, the average response in brain oxygenation during the handgrip exercise also did not differ between the groups (O2Hb change 1.20 ± 1.03 versus 1.49 ± 0.95 μmol, respectively, P = 0.262). In the total cohort, the average response in brain oxygenation during handgrip exercise was inversely correlated with dialysis vintage (P &lt; 0.05).

CONCLUSION

Dialysis modality does not appear to have an impact on brain oxygenation, as HD and PD patients presented similar responses during a mental and a mild physical task. Dialysis vintage may negatively affect brain oxygenation in ESKD individuals.

MO087: Ambulatory Blood Pressure Trajectories and Blood Pressure Variability in Kidney Transplant Recipients: A Comparative Study Against Hemodialysis Patients

BACKGROUND AND AIMS

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

METHOD

Two hundred four 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 period of a standard 48-h ABPM in HD. To evaluate the effect of renal replacement treatment and time on ambulatory BP levels, two-way-ANOVA for repeated-measurements was performed.

RESULTS

KTRs had significantly lower SBP and pulse-pressure (PP) levels compared with HD 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 &lt; 0.001); no significant differences were noted for DBP levels with the exception of second nighttime. Repeated-measurements-ANOVA showed a significant effect of RRT 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%CI: −21.5 to −6.2, P &lt; 0.001). Ambulatory systolic and diastolic BPV indices were significantly lower in KTRs than in HD during all periods studied (24-h SBP-ARV: 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 &lt; 0.001). No differences were noted in dipping pattern between the two groups.

CONCLUSION

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

MO858: Early Morning Haemodynamic Changes and Left Ventricular Hypertrophy and Mortality In Haemodialysis Patients

BACKGROUND AND AIMS

Amplified early morning increase in BP, a phenomenon accompanied by a parallel rise in heart rate (HR), is a marker of high cardiovascular risk in the general population. The early morning changes in these parameters have not been investigated in the haemodialysis population.

METHOD

In a pilot, single centre, study including a series of 58 haemodialysis patients we measured the pre-awakening BP and HR surges and the nocturnal dipping of the same parameters as well as other established indicators of autonomic function (weighted 24h systolic BP and HR variability) and tested their relationship with the left ventricular mass index (LVMI) and with the risk of death over a median follow up of 40 months.

RESULTS

The pre-awakening HR surge (r = –0.46; P = 0.001) was inversely associated with LVMI and the risk of death [HR (1 unit): 0.89, 95% confidence interval: 0.83–0.96; P = 0.001] while the corresponding BP surge largely failed to associate with these outcomes. The link between the pre-awakening HR surge with LVMI and death was robust and largely independent of established risk factors in the haemodialysis population, including the nocturnal dipping of BP. Weighted 24 h systolic BP and HR variability did not correlate with LVMI (all P &gt; 0.11) nor with the risk of death (P &gt; 0.11) and these parameters were also independent of the nocturnal dipping of systolic BP and HR.

CONCLUSION

This pilot study suggests that the low early morning changes in HR, likely reflecting enhanced sympathetic activity, entail a high risk for LVH and mortality in the haemodialysis population.

MO891: Poor Tolerability of the Standard, Extended, 48h Ambulatory Blood Pressure Monitoring in Haemodialysis Patients

BACKGROUND AND AIMS

Ambulatory blood pressure monitoring (ABPM), extended to 44h or 48h for the diagnosis of hypertension in end-stage kidney disease (ESKD) patients, is recommended by Consensus Documents of the American Society of Nephrology and the European Renal Association. About 10%–20% of individuals in the general population report sleeping problems and other symptoms during 24 h ABPM. Because the longer recording period (44 or 48 h versus 24 h), the notorious sleeping disturbances and the high symptom burden of the ESKD population, the feasibility of the technique may be limited in this population. However, the large-scale tolerability of ABPM in the haemodialysis population, has never been investigated.

METHOD

We performed an international survey of feasibility and tolerability of 48 h ABPM in six centres in three European countries. These centres are led by motivated clinical nephrologists, all members of the EURECA-m working group. 48 h ABPM recording was proposed to a large, representative sample of the whole dialysis population of these centres. Well validated instruments (AAMI/ESH/ISO) were applied in all centres. As recommended by the European Society of Hypertension guidelines, recordings were made at 15-min intervals during the day and 30 min during the night. Reasons for refusal to undergo the test were accurately registered. A tolerability (symptoms) questionnaire and a specific questionnaire for sleep evaluation were administered to all participants who underwent 48h ABPM. Reasons for not completing of the ABPM monitoring were systematically recorded.

RESULTS

In the whole haemodialysis population of participating centres including 735 patients, 440 (60%) were invited to participate in the study. Among these patients, 119 (27%) refused to undergo ABPM recording. Reasons for refusal were fear of discomfort (n = 30, 25%), measurement too long (n = 22, 18%), logistic problems (n = 17, 14%), previous negative experience (n = 13, 11%), clinical reasons (n = 12, 10%), other reasons (n = 25). Among the 321 patients who performed the 48h ABPM recording, 29 (9%) did not complete it and the main reason for interrupting the recording were discomfort [12 patients (41%)], followed by device failure [10 patients (34%)]. Among symptoms developed during the ABPM study, frequent interruption of sleeping because of noise or discomfort was reported by 32% of patients, followed by itching (24%) and pain during the measurements (20%). The detailed list of symptoms, is reported in the Table 1.

CONCLUSION

Overall, about 25% of haemodialysis patients consider 48h ABPM a laborious and discomforting test and prejudicially refuse to undergo it. Among patients who undergo 48h ABPM, itching and interruption of sleeping are complained by about 1/3 of patients. These figures are substantially higher than those reported in studies in the general population and in hypertensive patients and point to peculiar barriers at applying extended ABPM recordings in the haemodialysis population. Studies applying more tolerable instruments and a minimum set of measurements over a shorter time, with a reduced number of measurements overnight, are clinical research priority for extending the use of ABPM in the haemodialysis population.

MO198: Outcomes with Finerenone in Patients with Stage 4 Chronic Kidney Disease and Type 2 Diabetes: A Fidelity Subgroup Analysis

BACKGROUND AND AIMS

Patients with stage 4 chronic kidney disease (CKD) and type 2 diabetes (T2D) have a high residual risk of cardiovascular (CV) and kidney disease progression, and effective treatment options to reduce the risk are limited. The non-steroidal selective mineralocorticoid receptor antagonist finerenone has previously demonstrated significant cardiorenal benefits versus placebo in patients with stage 1–4 CKD [1–3]. This FIDELITY subgroup analysis investigated the effects of finerenone in patients with stage 4 CKD [estimated glomerular filtration rate (eGFR) &lt;30 mL/min/1.73 m2) versus those with stage 1–3 CKD (eGFR ≥ 30 mL/min/1.73 m2).

METHOD

FIDELIO-DKD and FIGARO-DKD were phase III trials of patients with CKD and T2D randomised 1:1 to finerenone or placebo. FIDELITY was an individual patient-level prespecified pooled efficacy and safety analysis of these studies. Efficacy outcomes included change in urine albumin-to-creatinine ratio (UACR) between baseline and month 4, change in eGFR over time, a kidney composite outcome (kidney failure, a sustained ≥57% decrease in eGFR from baseline over ≥ 4 weeks or renal death) and a CV composite outcome [CV death, non-fatal myocardial infarction, non-fatal stroke or hospitalization for heart failure (HHF)], as well as the individual components of these composite outcomes.

RESULTS

Of 13 023 patients included in the analysis, 890 patients (6.8%) had stage 4 CKD; key baseline characteristics are listed in Table 1. In patients with stage 4 CKD, finerenone reduced UACR by 31% vs placebo between baseline and month 4 [ratio of least-squares (LS) mean change 0.69; 95% confidence interval (CI) 0.63–0.77), an effect maintained for the duration of the study. Total eGFR slope (LS mean change in eGFR from randomisation to end of treatment) in patients with stage 4 CKD was –0.7 mL/min/1.73 m2/year with finerenone versus –1.6 mL/min/1.73 m2/year with placebo; the chronic eGFR slope (LS mean change in eGFR from month 4 to end of treatment) was –1.8 mL/min/1.73 m2/year with finerenone vs –3.2 mL/min/1.73 m2/year with placebo. The hazard ratio (HR) for risk of the kidney composite in stage 4 CKD was 1.01 (95% CI 0.75–1.37; Figure 1) for finerenone versus placebo. Reduction in risk of sustained ≥ 57% decrease in eGFR with finerenone (stage 4 CKD: HR 0.69, 95% CI 0.43–1.11) was similar between CKD subgroups (pinteraction = 0.71). Reduction in risk of the composite CV outcome (stage 4 CKD: HR 0.78, 95% CI 0.57–1.07) and HHF (stage 4 CKD: HR 0.99, 95% CI 0.62–1.58) was also consistent between CKD subgroups (pinteraction = 0.67 and 0.31, respectively). Overall, incidences of adverse events were balanced between treatment arms in patients with stage 4 CKD and stage 1–3 CKD. The incidence of hyperkalaemia leading to permanent discontinuation was low in patients with stage 4 CKD (3.2% versus 2.2% for finerenone versus placebo).

CONCLUSION

The cardiorenal benefits and safety profile of finerenone in FIDELITY were also observed in the subgroup of patients with stage 4 CKD.

MO090: Diagnostic Performance of Pre-Dialysis And Ambulatory Blood Pressure Levels in Men and Women Hemodialysis Patients

BACKGROUND AND AIMS

Ambulatory blood pressure (BP) control is worse in men than in women with chronic kidney disease or kidney transplantation. So far no study assessed in parallel possible effects of sex differences on the prevalence, control and BP phenotypes according to pre-dialysis and 48-h ABPM in hemodialysis patients. Further, no study has evaluated the diagnostic accuracy of pre-dialysis BP levels in men and women hemodialysis patients.

METHOD

129 male and 91 female hemodialysis patients that underwent 48-h ABPM with Mobil-O-Graph-NG were included in this analysis. Hypertension was defined as follows: (1) pre-dialysis BP ≥ 140/90 mmHg or use of antihypertensive agents, (2) 48-h BP ≥ 130/80 mmHg or use of antihypertensive agents.

RESULTS

The prevalence of hypertension was not different between men and women with the use of pre-dialysis BP (92.2% versus 92.3%, P = 0.987, respectively) or 48-h ABPM (92.2% versus 89%, P = 0.411). With the use of pre-dialysis BP men had significantly lower control rates than women (18.5% versus 32.1%, P = 0.025); a similar pattern of worse control in men was apparent with the use of ABPM, but the difference was not statistically significant (22.7% versus 28.4%, P = 0.360). The rate of patients with concordant lack of control by pre-dialysis and ABPM readings was significantly higher in men than women (65.3% versus 49.4%, P = 0.023); white-coat (14.9% versus 17.6%, P = 0.593) and masked hypertension (10.7% versus 18.8%, P = 0.101) did not differ between groups. However, the misclassifation rate with the use of pre-dialysis BP was lower in men than women. There was moderate or at best fair agreement between pre-dialysis and ambulatory BP with regards to the prevalence (men: κ-statistics = 0.39, P &lt; 0.001 and women: 0.27, P = 0.011) and control rates (κ-statistics = 0.25, P = 0.005 and 0.17, P = 0.124, respectively). Pre-dialysis BP ≥ 140/90 mmHg had sensitivity/specificity of 85.9%/51.4% in men and 72.4%/54.5% in women for the diagnosis of 48-h BP ≥ 130/80 mmHg. Receiver-operating-curve analyses confirmed this poor diagnostic performance.

CONCLUSION

The prevalence of hypertension is similar between men and women hemodialysis patients, but men have worse rates of office BP control. The diagnostic accuracy of pre-dialysis BP levels was equally poor in men and women hemodialysis patients.

FC085: Cerebral Oxygenation During Exercise Across Different Stages of Chronic Kidney Disease

BACKGROUND AND AIMS

Cognitive impairment and reduced exercise tolerance are common in patients with chronic kidney disease (CKD), in part due to reduced brain function. Proper brain function relies on sufficient blood flow and oxygen supply by the cerebral vasculature. A reduction in cerebral oxygenation of more than 10% may deteriorate brain function and influence the decision to continue exercise. This study aims to examine the cerebral oxygenation and blood volume during a mild physical stress as an index of brain activation in patients at different stages of CKD and controls without CKD.

METHOD

This is a preliminary analysis of an observational study enrolling patients with CKD stage 2–4 (matched for age and sex within the different stages) and controls without CKD. All participants underwent a 3-min intermittent handgrip exercise (HG) at 35% of their maximal voluntary contraction. Changes in prefrontal oxygenation (oxyhaemoglobin—O2Hb) and deoxyhaemoglobin—HHb) and total blood volume (total hemoglobin—tHb) were continuously recorded during HG-exercise by near-infrared spectroscopy (NIRS).

RESULTS

A total of 59 participants are included in this preliminary analyses (n = 11 controls, n = 15 stage 2 CKD, n = 18 stage 3 CKD and n = 15 stage 4 CKD patients). During HG-exercise, O2Hb significantly increased (P &lt; 0.001) and HHb remained relatively unchanged in all groups compared to pre-exercise values. However, this O2Hb increase was progressively lower with advancing CKD Stages (controls: 2.58 ± 1.43;  stage 2: 1.51 ± 1.31;  stage 3: 1.29 ± 0.97;  stage 4: 0.95 ± 0.92;  P = 0.006) (Figure). During HG, tHb (an index of microvascular blood volume) increased significantly in controls, stage 2 and stage 3 CKD patients (P &lt; 0.05) but not in stage 4 CKD patients (P = 0.100). As before this tHb increase was progressively lower with advancing CKD stages (P = 0.030). Controlling for age differences between groups did not alter the above observations.

CONCLUSION

Brain activation/response during a mild physical task appears to decrease with advancing CKD as suggested by the smaller rise in cerebral oxygenation and blood volume. This may contribute both impaired cognitive function and reduced exercise tolerance with advancing CKD.

Ambulatory blood pressure trajectories and blood pressure variability in kidney transplant recipients: a comparative study against haemodialysis 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.

Early morning hemodynamic changes and left ventricular hypertrophy and mortality in hemodialysis patients

INTRODUCTION

An exaggeration of the early morning increase in BP, a phenomenon accompanied by a parallel rise in heart rate (HR), is a marker of high cardiovascular risk. The early morning changes in these parameters have not been investigated in the hemodialysis population.

METHODS

In a pilot, single center study including a series of 58 patients we measured the pre-awakening BP and HR surges and the nocturnal dipping of the same parameters as well as other established indicators of autonomic function (weighted 24 h systolic BP and HR variability) and tested their relationship with the left ventricular mass index (LVMI) and with the risk of death over a median follow up of 40 months.

RESULTS

The pre-awakening HR surge (r = - 0.46, P = 0.001) but not the corresponding BP surge (r = - 0.1, P = 0.98) was associated with LVMI and the risk of death [HR (1 unit): 0.89, 95% CI 0.83-0.96, P = 0.001]. The link between the pre-awakening HR surge with these outcome measures was robust and largely independent of established risk factors in the hemodialysis population, including the nocturnal dipping of BP. Weighted 24 h systolic BP and HR variability did not correlate with LVMI (all P > 0.11) nor with the risk of death (P > 0.11) and were also independent of the nocturnal dipping of systolic BP and HR.

CONCLUSION

This pilot study suggests that the low early morning changes in HR, likely reflecting enhanced sympathetic activity, entail a high risk for left ventricular hypertrophy (LVH) and mortality in the hemodialysis population.

Blood pressure targets in CKD 2021: the never-ending guidelines debacle

In 2021, two updated clinical guidelines were published, providing guidance on blood pressure (BP) targets for people with chronic kidney disease (CKD). Kidney Disease: Improving Global Outcomes (KDIGO) updated its 2012 Clinical Practice Guideline for the Management of BP in CKD. Different systolic blood pressure (SBP) and diastolic blood pressure (DBP) targets for CKD (<130/80 and <140/90 mmHg, respectively, for people with a urinary albumin: creatinine ratio >30 mg/g or without pathological albuminuria) were replaced by a single number: an SBP target of <120 mmHg is suggested, when tolerated. This represents a major decrease in the SBP target and the abandonment of DBP targets. The European Society of Cardiology (ESC) also published a 2021 Clinical Guideline on Cardiovascular Disease Prevention in Clinical Practice that updates a prior 2016 guideline on prevention and the 2018 ESC/European Society of Hypertension Clinical Practice Guidelines for the Management of Arterial Hypertension. The 2021 ESC guideline was endorsed by 12 European scientific societies. The recommended office BP targets for people with CKD are <140–130 mmHg SBP (lower SBP is acceptable if tolerated) and <80 mmHg DBP. The question is: What should the practicing physician do now: treat hypertension in people with CKD to an SBP target of <120 mmHg or to a target of <140–130 mmHg? Major guideline bodies are aware of the activities of other major players. There is an urgent need for guideline bodies to establish communication channels, search consensus on major issues that impact the health of hundreds of millions of people worldwide and end individualism in guidelines generation.

Sex differences in ambulatory blood pressure levels, control, and phenotypes of hypertension in kidney transplant recipients

OBJECTIVES

Ambulatory blood pressure (BP) control is worse in men compared with women with chronic kidney disease (CKD) and this may partially explain the faster CKD progression in men. This is the first study investigating possible sex differences in prevalence, control and phenotypes of hypertension in kidney transplant recipients (KTRs) with office-BP and 24-h ambulatory BP monitoring (ABPM).

METHODS

This cross-sectional study included 136 male and 69 female stable KTRs who underwent office-BP measurements and 24-h ABPM. Hypertension thresholds for office and ambulatory BP were defined according to the 2017 ACC/AHA and 2021 KDIGO guidelines for KTRs.

RESULTS

Age, time from transplantation, eGFR and history of major comorbidities did not differ between groups. Office SBP/DBP levels were insignificantly higher in men than women (130.3 ± 16.3/77.3 ± 9.4 vs. 126.4 ± 17.8/74.9 ± 11.5 mmHg; P = 0.118/0.104) but daytime SBP/DBP was significantly higher in men (128.5 ± 12.1/83.0 ± 8.2 vs. 124.6 ± 11.9/80.3 ± 9.3 mmHg; P = 0.032/P = 0.044). No significant between-group differences were detected for night-time BP. The prevalence of hypertension was similar by office-BP criteria (93.4 vs. 91.3%; P = 0.589), but higher in men than women with ABPM (100 vs. 95.7%; P = 0.014). The use of ACEIs/ARBs and CCBs was more common in men. Office-BP control was similar (43.3 vs. 44.4%, P = 0.882), but 24-h control was significantly lower in men than women (16.9 vs. 30.3%; P = 0.029). White-coat hypertension was similar (5.1 vs. 7.6%; P = 0.493), whereas masked hypertension was insignificantly more prevalent in men than women (35.3 vs. 24.2%; P = 0.113).

CONCLUSION

BP levels, hypertension prevalence and control are similar by office criteria but significantly different by ABPM criteria between male and female KTRs. Worse ambulatory BP control in male compared with female KTRs may interfere with renal and cardiovascular outcomes.

Assessment of hypertension in kidney transplantation by ambulatory blood pressure monitoring: a systematic review and meta-analysis

Background

Hypertension (HTN) is common following renal transplantation and it is associated with adverse effects on cardiovascular (CV) and graft health. Ambulatory blood pressure monitoring (ABPM) is the preferred method to characterize blood pressure (BP) status, since HTN misclassification by office BP (OBP) is quite common in this population. We performed a systematic review and meta-analysis aimed at determining the clinical utility of 24-h ABPM and its potential implications for the management of HTN in this population.

Methods

Ovid-MEDLINE and PubMed databases were searched for interventional or observational studies enrolling adult kidney transplant recipients (KTRs) undergoing 24-h ABP readings compared with OBP or home BP. The main outcome was the proportion of KTRs diagnosed with HTN by ABPM, home or OBP recordings. Additionally, day-night BP variability and dipper/non-dipper status were assessed.

Results

Forty-two eligible studies (4115 participants) were reviewed. A cumulative analysis including 27 studies (3481 participants) revealed a prevalence of uncontrolled HTN detected by ABPM of 56% [95% confidence interval (CI) 46-65%]. The pooled prevalence of uncontrolled HTN according to OBP was 47% (95% CI 36-58%) in 25 studies (3261 participants). Very few studies reported on home BP recordings. The average concordance rate between OBP and ABPM measurements in classifying patients as controlled or uncontrolled hypertensive was 66% (95% CI 59-73%). ABPM revealed HTN phenotypes among KTRs. Two pooled analyses of 11 and 10 studies, respectively, revealed an average prevalence of 26% (95% CI 19-33%) for masked HTN (MHT) and 10% (95% CI 6-17%) for white-coat HTN (WCH). The proportion of non-dippers was variable across the 28 studies that analysed dipping status, with an average prevalence of 54% (95% CI 45-63%).

Conclusions

In our systematic review, comparison of OBP versus ABP measurements disclosed a high proportion of MHT, uncontrolled HTN and, to a lesser extent, WCH in KTRs. These results suggest that HTN is not adequately diagnosed and controlled by OBP recordings in this population. Furthermore, the high prevalence of non-dippers confirmed that circadian rhythm is commonly disturbed in KTRs.

Endothelial and microvascular function in liver cirrhosis: an old concept that needs re-evaluation?

Liver cirrhosis is characterized by significant circulatory dysregulation, related to an imbalance among several vasodilating agents, mainly nitric oxide. In contrast to portal vein and macrovascular hemodynamic alterations, which have been rather well described, the peripheral microcirculatory and endothelial structure and function in this population are less well studied. Endothelial dysfunction is characterized by an imbalance between endothelium-derived relaxing and contracting factors. A number of methods have been used to assess endothelial and microvascular function in human studies. Venous occlusion plethysmography was used for many years as the gold standard for evaluating endothelial function, but flow-mediated dilatation (FMD) of the forearm is currently the most frequently used method. In patients with cirrhosis, the few existing studies have mainly used FMD, but the relevant results are largely contradictory. In recent years, several noninvasive and easily applicable methods, such as near-infrared spectroscopy, laser speckle contrast imaging, peripheral arterial tonometry, optical coherence tomography and nailfold video-capillaroscopy, have been increasingly used to assess peripheral microvascular function and have demonstrated a number of advantages. In this review, we present functional methods to evaluate peripheral microvascular and endothelial function, and we discuss the existing evidence on circulatory dysfunction in patients with liver cirrhosis.

Renin-angiotensin system blockers during the COVID-19 pandemic: an update for patients with hypertension and chronic kidney disease

Hypertension and chronic kidney disease (CKD) are among the most common comorbidities associated with coronavirus disease 2019 (COVID-19) severity and mortality risk. Renin–angiotensin system (RAS) blockers are cornerstones in the treatment of both hypertension and proteinuric CKD. In the early months of the COVID-19 pandemic, a hypothesis emerged suggesting that the use of RAS blockers may increase susceptibility for COVID-19 infection and disease severity in these populations. This hypothesis was based on the fact that angiotensin-converting enzyme 2 (ACE2), a counter regulatory component of the RAS, acts as the receptor for severe acute respiratory syndrome coronavirus 2 cell entry. Extrapolations from preliminary animal studies led to speculation that upregulation of ACE2 by RAS blockers may increase the risk of COVID-19-related adverse outcomes. However, these hypotheses were not supported by emerging evidence from observational and randomized clinical trials in humans, suggesting no such association. Herein we describe the physiological role of ACE2 as part of the RAS, discuss its central role in COVID-19 infection and present original and updated evidence from human studies on the association between RAS blockade and COVID-19 infection or related outcomes, with a particular focus on hypertension and CKD.

Cardiopulmonary reserve examined with cardiopulmonary exercise testing in individuals with chronic kidney disease: A systematic review and meta-analysis

BACKGROUND

Patients with chronic kidney disease (CKD) often present reduced physical activity and exercise tolerance due to factors relevant to co-existing disturbances of the cardiac, nervous and muscular systems. Cardiopulmonary exercise testing (CPET) is used for clinical evaluation of exercise limitation and related symptoms (i.e., dyspnea, fatigue) in several medical fields.

OBJECTIVES

This is a systematic review and meta-analysis of studies using CPET technology to examine cardiopulmonary reserve in individuals with versus without CKD.

METHODS

Literature search involved PubMed, Web of Science and Scopus databases; manual search of article references and of gray literature was also performed. Observational studies and randomized trials that used CPET for patients with CKD stage 1-5 versus controls were eligible. The primary outcome was peak oxygen uptake (VO₂peak). The Newcastle-Ottawa Scale was used to evaluate the quality of retrieved studies.

RESULTS

From an initial 4944 literature records, we identified 29 studies fulfilling the inclusion criteria; of these, 25 studies (2,213 participants) with complete data were included in the final meta-analysis. VO₂peak was significantly lower in CKD patients than controls without CKD [standardized mean difference (SMD) -1.40, 95% confidence interval (CI) -1.68; -1.13)]. Values were lower for CKD than non-CKD individuals for oxygen consumption at anaerobic threshold (SMD -1.06, 95% CI -1.34; -0.79) and maximum workload [weighted mean difference (WMD) -58.26, 95% CI 74.14; -42.38]. In 3 studies, CKD patients had higher VO₂peak than controls with heart failure without CKD (WMD 6.60, 95% CI 3.02; 10.18). Sensitivity analyses confirmed the robustness of these findings.

CONCLUSIONS

VO₂peak and other commonly analyzed CPET variables were lower in patients with CKD than controls, which indicates reduced functional cardiopulmonary reserve in CKD. In contrast, patients with CKD performed better than controls with heart failure without CKD. Overall, rehabilitation programs should be more widely applied to individuals with CKD.

PROSPERO REGISTRATION NUMBER

CRD42021227805.

Role of hypertension in kidney transplant recipients

Cardiovascular events are one of the leading causes of mortality in kidney transplant recipients. Hypertension is the most common comorbidity accompanying chronic kidney disease, with prevalence remaining as high as 90% even after kidney transplantation. It is often poorly controlled. Abnormal blood pressure profiles, such as masked or white-coat hypertension, are also extremely common in these patients. The pathophysiology of blood pressure elevation in kidney transplant recipients is complex and includes transplantation-specific risk factors, which are added to the traditional or chronic kidney disease-related factors. Despite these observations, hypertension management has been an under-researched area in kidney transplantation. Thus, relevant evidence derives either from studies in the general population or from small trials in kidney transplant recipients. Based on the relevant guidelines in the general population, lifestyle modifications should probably be applied as the first step of hypertension management in kidney transplant recipients. The optimal pharmacological management of hypertension in kidney transplant recipients is also not clear. Dihydropyridine calcium channel blockers are commonly used as first line agents because of their lack of adverse effects on the kidney, while other antihypertensive drug classes are under-utilised due to fear of the possible haemodynamic consequences on renal function. This review summarizes the existing data on the pathophysiology, diagnosis, prognostic significance and management of hypertension in kidney transplantation.