The association of sex differences in ambulatory blood pressure with cardiovascular events and mortality in dialysis patients.

Male patients with pre-dialysis chronic kidney disease (CKD) have worse ambulatory blood pressure (BP) control than females; this is associated with higher mortality. Male hemodialysis patients have higher ambulatory BP levels than females. This analysis aimed to investigate the association of sex differences in ambulatory BP with cardiovascular events and mortality in hemodialysis individuals. 129 male and 91 female hemodialysis patients with valid 48-h BP monitoring were followed for 53.4 ± 31.1 months. The primary endpoint was cardiovascular mortality; the secondary endpoint was a composite of cardiovascular death, non-fatal myocardial infarction, non-fatal stroke, resuscitation after cardiac arrest, heart failure-hospitalization, coronary or peripheral revascularization. Cumulative freedom from the primary endpoint was lower for women (logrank-p = 0.032), while cumulative-freedom from the secondary endpoint did not differ significantly between-groups (logrank-p = 0.644). The crude risk for cardiovascular mortality was significantly higher in women (HR = 1.613, 95% CI [1.037, 2.509]). The crude risk for the combined endpoint was not different between the two groups (HR = 0.918, 95% CI [0.638, 1.320]). After adjusting for major risk factors (age, diabetes, dialysis vintage, coronary disease and hemoglobin) no significant differences in the risk for both the primary and the secondary endpoint were observed between women and men (primary: HR = 1.295 (95% CI [0.808, 2.078]), secondary: HR = 0.763 (95% CI [0.521, 1.118])). After additional adjustment for 44-h systolic BP the above relationships did not alter (primary: HR = 1.329 (95% CI [0.826, 2.137]), secondary: HR = 0.808 (95% CI [0.551, 1.184])). In conclusion, female hemodialysis patients have higher crude but similar adjusted cardiovascular mortality rates compared to male counterparts. In contrast to pre-dialysis CKD, the neutral relationship between gender and adverse cardiovascular outcomes in hemodialysis is not further affected by ambulatory BP.

The effect of different dialysate sodium concentrations on ambulatory blood pressure in hemodialysis patients: a prospective interventional study.

Background: Hypertension is associated with increased morbidity and mortality in hemodialysis patients. Existing recommendations suggest reduction of sodium load, but the effect of dialysate sodium on blood pressure (BP) is not fully elucidated. The aim of the present study is to investigate the effect of different dialysate sodium concentrations on 72-h ambulatory BP in hemodialysis patients. Methods: This prospective study included patients on standard thrice-weekly hemodialysis. All patients initially underwent six sessions with dialysate sodium concentration of 137 meq/L, followed consecutively by another six sessions with dialysate sodium of 139 meq/L and, finally, six sessions with dialysate sodium of 141 meq/L. At the start of the sixth hemodialysis session on each sodium concentration, 72-h ABPM was performed over the long interdialytic interval to evaluate ambulatory systolic and diastolic BP (SBP and DBP) during the overall 72-h, different 24-h, daytime and night-time periods. Results: Twenty-five patients were included in the final analysis. A significant increase in the mean 72-h SBP was observed with higher dialysate sodium concentrations (124.8 ± 16.6 mmHg with 137 meq/L vs 126.3 ± 17.5 mmHg with 139 meq/L vs 132.3 ± 19.31 mmHg with 141 meq/L, P = 0.002). Similar differences were noted for DBP; 72-h DBP was significantly higher with increasing dialysate sodium concentrations (75.1 ± 11.3 mmHg with 137 meq/L vs 76.3 ± 13.7 mmHg with 139 meq/L vs 79.5 ± 13.9 mmHg with 141 meq/L dialysate sodium, P = 0.01). Ambulatory BP during the different 24-h intervals, daytime and night-time periods was also progressively increasing with increasing dialysate sodium concentration. Conclusion: This pilot study showed a progressive increase in ambulatory BP with higher dialysate sodium concentrations. These findings support that lower dialysate sodium concentration may help towards better BP control in hemodialysis patients.

Dialysate sodium and short-term blood pressure variability in patients with intradialytic hypertension: a randomized crossover study.

Increased blood pressure (BP) variability (BPV) is associated with high cardiovascular risk in hemodialysis. Patients with intradialytic hypertension (IDH) also exhibit an increased cardiovascular risk compared to hemodialysis patients without this condition. The impact of non-pharmacological BP-lowering interventions on BPV in this population remains unknown. This analysis evaluated the effect of low (137mEq/L) compared to standard (140mEq/L) dialysate sodium concentration on short-term BPV in patients with IDH. In a randomized cross-over manner, 29 IDH patients underwent 4 hemodialysis sessions with low (137mEq/L) followed by 4 sessions with standard (140mEq/L) dialysate sodium or vice versa. 48 h ambulatory BP measurement was performed from the start of the 4th session on each dialysate sodium. BPV indices during the 48 h, 24 h, day-time and night-time periods were calculated. Mean 48 h BP was 5.3/2.6 mmHg lower with low compared to standard dialysate sodium concentration, (p = 0.005/p = 0.007 respectively). All 48 h systolic BPV indices examined showed non-significant differences between low and standard dialysate sodium (SBP-SD: 16.99 ± 5.39 vs. 16.98 ± 4.33 mmHg, p = 0.982; SBP-wSD: 15.93 ± 5.02 vs. 16.12 ± 4.16 mmHg, p = 0.769; SBP-ARV: 11.99 ± 3.67 vs. 11.45 ± 3.35 mmHg, p = 0.392; SBP-CV: 12.36 ± 3.65 vs. 11.92 ± 3.18%, p = 0.302, with low vs. standard dialysate sodium, respectively). Diastolic BPV indices were numerically, but not statistically, lower with low dialysate sodium. Overall, significant differences were observed in some comparisons with a trend for lower BPV during day-time 2 and higher BVP during night-time 2 with low dialysate sodium. In conclusion, low dialysate sodium concentration does not affect BPV levels in patients with IDH. Future research should explore alternative interventions to reduce BP and BPV in this high-risk population.

Right Ventricular and Right Atrial Strain Are Associated with Kidney Dysfunction in Acute Heart Failure.

BACKGROUND: In acute heart failure (HF), low cardiac output and venous congestion are pathophysiological mechanisms that contribute to renal function impairment. This study investigated the association between advanced echocardiographic measures of right ventricular and atrial function and renal impairment in patients with acute HF. METHODS AND RESULTS: A total of 377 patients hospitalized for acute HF were prospectively evaluated. Estimated glomerular filtration rate (eGFR) on admission was measured using the 2021 Chronic Kidney Disease Epidemiology Collaboration creatinine equation. Advanced echocardiographic assessment was performed on admission. Patients with eGFR < 45 mL/min/1.73 m2 were more likely to have chronic heart failure, chronic atrial fibrillation, and type 2 diabetes mellitus compared to patients with eGFR ≥ 45 mL/min/1.73 m2. Patients with lower eGFR had lower cardiac output, higher mean E/e' ratio, larger right ventricular (RV) size, worse RV free wall longitudinal strain, more impaired right atrial (RA) reservoir strain, and more frequent severe tricuspid regurgitation. RV free wall longitudinal strain and RA reservoir strain were the only independent echocardiographic associates of low eGFR, whereas cardiac output was not. CONCLUSIONS: Impaired RV and RA longitudinal strain were independently associated with eGFR < 45 mL/min/1.73 m2 in acute HF, while reduced cardiac output was not. This suggests that RV and RA dysfunction underlying venous congestion and increased renal afterload are more important pathophysiological determinants of renal impairment in acute HF than reduced cardiac output.

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.

Prevalence, awareness, and control of hypertension in Greece before and after the COVID-19 pandemic: May Measurement Month survey 2019-2022.

OBJECTIVE: The COVID-19 pandemic had an adverse impact on several cardiovascular risk factors. This study investigated the prevalence, awareness and treatment of hypertension in Greece before and after the pandemic. Data were collected in the context of the May Measurement Month (MMM) global survey initiated by the International Society of Hypertension. METHODS: Adult volunteers (age ≥ 18 years) were recruited through opportunistic screening in public areas across cities in Greece in 2019 and 2022. Medical history and triplicate sitting blood pressure (BP) measurements were taken using validated automated upper-arm cuff devices. The data were uploaded to the international MMM cloud platform. Hypertension was defined as systolic BP ≥ 140 mm Hg and/or diastolic ≥90 mm Hg and/or self-reported use of drugs for hypertension. The same threshold was used to define uncontrolled BP in treated individuals. RESULTS: Data from 12,080 adults were collected (5,727/6,353 in MMM 2019/2022; men 46/49%, p < 0.01; mean age 52.7 ± 16.6/54.8 ± 16.2, p < 0.001; smokers, 24.7/30.5, p < 0.001; diabetics 12/11.5%, p = NS; cardiovascular disease 5/5.8%, p = NS). The prevalence of hypertension was 41.6/42.6% (MMM 2019/2022, p = NS), with 21.3/27.5% of individuals with hypertension being unaware of their condition (p < 0.001), 5.6/2.4% aware untreated (p < 0.001), 24.8/22.1% treated uncontrolled (p < 0.05), and 48.3/47.8% treated controlled (p = NS). CONCLUSION: In Greece, the COVID-19 pandemic did not appear to affect the prevalence and control of hypertension; however, the rate of undiagnosed hypertension was higher after the pandemic. National strategies need to be implemented for the early detection and optimal management of hypertension in the general population in Greece.

Low dialysate sodium and 48-h ambulatory blood pressure in patients with intradialytic hypertension: a randomized crossover study.

BACKGROUND AND HYPOTHESIS: Intradialytic-hypertension (IDH) is associated with increased risk for cardiovascular events and mortality. Patients with IDH exhibit higher 48-h blood pressure (BP) levels than patients without this condition. Volume and sodium excess are considered a major factor contributing in the development of this phenomenon. This study evaluated the effect of low (137mEq/L) compared to standard (140mEq/L) dialysate sodium concentration on 48-h BP in patients with IDH. METHODS: In this randomized, single-blind, crossover study, 29 patients with IDH underwent 4 hemodialysis sessions with low (137mEq/L) followed by 4 sessions with standard (140mEq/L) dialysate sodium or vice-versa. Mean 48-h BP, pre-/post-dialysis and intradialytic BP, pre-dialysis weight, interdialytic weight gain (IDWG) and lung ultrasound B-lines were assessed. RESULTS: Mean 48-h SBP/DBP were significantly lower with low compared to standard dialysate sodium concentration (137.6±17.0/81.4±13.7mmHg with low vs 142.9±14.5/84.0±13.9mmHg with standard dialysate sodium, p=0.005/p=0.007 respectively); SBP/DBP levels were also significantly lower during the 44-h and different 24-h periods. Low dialysate sodium significantly reduced post-dialysis (SBP/DBP: 150.3±22.3/91.2±15.1mmHg with low vs 166.6±17.3/94.5±14.9mmHg with standard dialysate sodium, p<0.001/p=0.134 respectively) and intradialytic (141.4±18.0/85.0±13.4mmHg with low vs 147.5±13.6/88.1±12.5mmHg with standard dialysate sodium, p=0.034/p=0.013, respectively) BP compared with standard dialysate sodium. Pre-dialysis weight, IDWG and pre-dialysis B-lines were also significantly decreased with low dialysate sodium. CONCLUSIONS: Low dialysate sodium concentration significantly reduced 48-h ambulatory BP compared with standard dialysate sodium in patients with IDH. These findings support low dialysate sodium as a major non-pharmacologic approach for BP management in patients with IDH.Registered at ClinicalTrials.gov with study number NCT05430438.

Changes in right ventricular dimensions, function, and pulmonary circulation loading according to the degree of interdialytic weight gain in maintenance hemodialysis patients.

INTRODUCTION: The aim of this study was to investigate changes in echocardiographic right ventricular (RV) indices in relation to the degree of fluid accumulation between hemodialysis sessions, evaluated according to the recommended threshold of interdialytic-weight-gain corrected for dry weight (IDWG%). METHODS: A post-hoc analysis was performed using data from 41 maintenance hemodialysis patients. Patients were divided into a higher (>4.5%) and a lower (<4.5%) IDWG% group and underwent an echocardiographic assessment at the start and the end of the 3-day and the 2-day interdialytic interval. RESULTS: RV systolic pressure (RVSP) increments were more pronounced in the higher compared to the lower IDWG% group (16.43 ± 5.37 vs. 14.11 ± 13.38 mm Hg respectively, p = 0.015) over the 3-day interval, while changes in RV filling pressures, did not differ significantly between the groups (p = 0.84). CONCLUSIONS: During the 3-day interdialytic interval, pulmonary circulation is particularly overloaded in patients with fluid accumulation higher than the recommended thresholds, as evidenced by higher RVSP elevations.

Effects of sodium-glucose co-transporter 2 inhibitors on heart failure events in chronic kidney disease: a systematic review and meta-analysis.

AIMS: Sodium-glucose co-transporter 2 (SGLT-2) inhibitors significantly reduce the risk for hospitalizations for heart failure (HF) in patients with diabetes, and HF; findings in patients with chronic kidney disease (CKD) are not uniform. We aimed to perform a meta-analysis exploring the effect of SGLT-2 inhibitors on HF events in patients with CKD and across subgroups defined by baseline kidney function. METHODS AND RESULTS: A systematic search in major electronic databases was performed. Randomized controlled trials (RCTs) providing data on the effect of SGLT-2 inhibitors on the primary outcome, time to hospitalization or urgent visit for worsening HF in patients with prevalent CKD at baseline or across subgroups stratified by baseline estimated glomerular-filtration-rate (eGFR) were included. Twelve studies (n = 89,191 participants) were included in the meta-analysis. In patients with CKD, treatment with SGLT-2 inhibitors reduced the risk for HF events by 32% compared to placebo [hazard ratio (HR) 0.68; 95% confidence interval (CI) 0.63-0.73]. Reduction in HF events with SGLT-2 inhibitors was more prominent in patients with eGFR <60 ml/min/1.73 m2 (HR 0.68; 95% CI 0.62-0.74) than in those with eGFR ≥60 ml/min/1.73 m2 (HR 0.76; 95% CI 0.69-0.83). Subgroup analysis according to type of SGLT-2 inhibitor showed a consistent treatment effect across all studied agents (p-subgroup-analysis = 0.44). Sensitivity analysis including data from studies including only diabetic patients showed an even more pronounced effect in eGFR subgroup <60 ml/min/1.73 m2 (HR 0.62; 95% CI 0.54-0.70). CONCLUSION: Treatment with SGLT-2 inhibitors led to a significant reduction in HF events in patients with CKD. Such findings may change the landscape of prevention of HF events in patients with advanced CKD. PROSPERO Registration number CRD42022382857.

Uromodulin biology.

Uromodulin is a kidney-specific glycoprotein which is exclusively produced by the epithelial cells lining the thick ascending limb and early distal convoluted tubule. It is currently recognized as a multifaceted player in kidney physiology and disease, with discrete roles for intracellular, urinary, interstitial and serum uromodulin. Among these, uromodulin modulates renal sodium handling through the regulation of tubular sodium transporters that reabsorb sodium and are targeted by diuretics, such as the loop diuretic-sensitive Na+-K+-2Cl- cotransporter type 2 (NKCC2) and the thiazide-sensitive Na+/Cl- cotransporter (NCC). Given these roles, the contribution of uromodulin to sodium-sensitive hypertension has been proposed. However, recent studies in humans suggest a more complex interaction between dietary sodium intake, uromodulin and blood pressure. This review presents an updated overview of the uromodulin's biology and its various roles, and focuses on the interaction between uromodulin and sodium-sensitive hypertension.

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.

Autonomic Nervous System Dysfunction in Peritoneal Dialysis Patients: An Underrecognized Cardiovascular Risk Factor?

BACKGROUND: In patients with end-stage kidney disease (ESKD) receiving peritoneal dialysis (PD), cardiovascular events represent the predominant cause of morbidity and mortality, with cardiac arrhythmias and sudden death being the leading causes of death in this population. Autonomic nervous system (ANS) dysfunction is listed among the non-traditional risk factors accounting for the observed high cardiovascular burden, with a plethora of complex and not yet fully understood pathophysiologic mechanisms being involved. SUMMARY: In recent years, preliminary studies have investigated and confirmed the presence of ANS dysfunction in PD patients, while relevant results from cohort studies have linked ANS dysfunction with adverse clinical outcomes in these patients. In light of these findings, ANS dysfunction has been recently receiving wider consideration as an independent cardiovascular risk factor in PD patients. The aim of this review was to describe the mechanisms involved in the pathogenesis of ANS dysfunction in ESKD and particularly PD patients and to summarize the existing studies evaluating ANS dysfunction in PD patients. KEY MESSAGES: ANS dysfunction in PD patients is related to multiple complex mechanisms that impair the balance between SNS/PNS, and this disruption represents a crucial intermediator of cardiovascular morbidity and mortality in this population.

The effect of standard percutaneous nephrolithotomy, miniaturized percutaneous nephrolithotomy and retrograde intrarenal surgery on biomarkers of renal injury: a randomized clinical trial.

Background: Observational studies on the association of endourological procedures with renal parenchymal damage are lacking. This randomized trial examined the effect of standard percutaneous nephrolithotomy (sPCNL) in comparison with miniaturized-PCNL (mini-PCNL) and retrograde intrarenal surgery (RIRS) for nephrolithiasis treatment on novel biomarkers of renal injury. Methods: Seventy-five patients were randomized in a 1:1:1 ratio to receive sPCNL, mini-PCNL and RIRS for nephrolithiasis. The ratios of neutrophil gelatinase-associated lipocalin (NGAL), kidney injury molecule-1 (KIM-1) and interleukin-18 (IL-18) normalized for urinary creatinine (Cr) were calculated from urine samples collected at baseline (2-h preoperatively) and at 2-, 6-, 24- and 48-h postoperatively. Two-way mixed analysis of variance (ANOVA) for repeated measurements was used to evaluate the effects of type of procedure and time on studied biomarkers. Results: Between baseline and 2-h postoperatively, no significant differences were observed in NGAL/Cr changes between sPCNL [median (interquartile range) 9.46 (4.82-14.9)], mini-PCNL [12.78 (1.69-25.24)] and RIRS [6.42 (2.61-23.90)] (P = .902). Similarly, no between-group differences were observed for KIM-1/Cr (P = .853) and IL-18 (P = .980) at 2 h, and all biomarkers at any time-point postoperatively. Within-groups, significant increases from baseline were noted for NGAL/Cr (sPCNL, P < .001; mini-PCNL, P < .001; RIRS, P = .001), KIM-1/Cr and IL-18/Cr at 2 h; progressively lower increases from baseline were noted in all groups for KIM-1/Cr and IL-18/Cr at 6-, 24- and 48-h postoperatively. As such, a significant effect of time but not of type of procedure was evidenced with two-way mixed ANOVA. No significant between-group differences were observed in acute kidney injury incidence and complications. Conclusions: The endourological procedures under study are associated with similar patterns of early tubular injury, detected by novel biomarkers, which is largely reduced within 48 h and no changes in glomerular function.

Heart rate variability at rest and in response to stress: Comparative study between hemodialysis and peritoneal dialysis patients.

Cardiac arrhythmias and sudden death are the leading causes of mortality in end-stage kidney disease (ESKD). Autonomic nervous system (ANS) dysfunction contributes to this arrhythmogenic background. This study compared heart rate variability (HRV) indices between hemodialysis (HD) and peritoneal dialysis (PD) patients, both at rest and in response to mental and physical stimulation maneuvers. Thirty-four HD and 34 PD patients matched for age, sex, and dialysis vintage, and 17 age- and sex-matched controls were studied. ANS function was examined by linear and non-linear HRV indices. Heart rate was recorded continuously (Finometer-PRO) at rest and during ANS maneuvers (orthostatic, mental-arithmetic, sit-to-stand, handgrip exercise tests). At rest, no significant differences between HD and PD were observed in HRV (root mean square of successive differences [RMSSD]: HD = 57.1 ± 81.1 vs PD = 69.6 ± 113.4 ms; P = 0.792), except for detrended fluctuation analysis (DFA-α1) (HD = 0.87 ± 0.40 vs PD = 0.70 ± 0.20; P = 0.047). DFA-α1 was significantly lower in PD than controls (1.00 ± 0.33; P < 0.05). All HRV indices during the mental-arithmetic test (RMSSD: HD = 128.2 ± 346.0 vs PD = 87.5 ± 150.0 ms; P = 0.893) and the physical stress tests were similar between HD and PD. The standard deviation along the line-of-identity (SD2)/the standard deviation perpendicular to the line-of-identity (SD1) ratio during mental-arithmetic was marginally lower in HD and significantly lower in PD than controls (PD = 1.31 ± 0.47 vs controls = 1.79 ± 0.64; P < 0.05). Both dialysis groups presented similar patterns in HRV responses during orthostatic and handgrip exercise tests. After the sit-to-stand, RMSSD, SD1, SD2, and DFA-α2 were higher compared to rest only in HD (RMSSD = 57.1 ± 81.1 vs 126.7 ± 185.7 ms; P = 0.028), suggesting a greater difficulty of HD patients in recovering normal ANS function in response to physical stress. In conclusion, HRV indices at rest and after mental and physical stimulation did not differ between HD and PD; however, the ANS responses following the sit-to-stand test were more impaired in HD. These findings suggest that ANS dysfunction is not largely affected by dialysis modality, but small differences in normal ANS recovery may exist.

Hyperkalemia in chronic kidney disease: a focus on potassium lowering pharmacotherapy.

INTRODUCTION: Hyperkalemia is one of the most common electrolyte disorders in chronic kidney disease (CKD) and is associated with serious adverse outcomes. Hyperkalemia risk is even greater when CKD patients also have additional predisposing conditions such as diabetes or heart failure. Renin-angiotensin-aldosterone-system blockers are first-line treatments for cardio- and nephroprotection, but their use is often limited due to K+ elevation, resulting in high rates of discontinuation. AREAS COVERED: This article provides an overview of factors interfering with K+ homeostasis and discusses recent data on newer therapeutic agents used for the treatment of hyperkalemia. A detailed literature search was performed in two major databases (PubMed/MEDLINE and Scopus) up to April 2023. EXPERT OPINION: Major clinical trials have tested new and promising kidney protective therapies such as sodium/glucose-cotransporter-2 inhibitors and mineralocorticoid-receptor-antagonists, with promising results. Until recently, the only treatment option for hyperkalemia was the cation-exchanging resin sodium-polystyrene-sulfonate. However, despite its common use, the efficacy and safety data of this drug in the long-term management of hyperkalemia are scarce. During the last decade, two novel orally administered K+-exchanging compounds (patiromer and sodium-zirconium-cyclosilicate) have been approved for the treatment of adults with hyperkalemia, as they both effectively reduce elevated serum K+ and maintain chronically K+ balance within the normal range with an excellent tolerability and no serious adverse events.