Harnessing the eccrine sweat glands for the management of interdialytic weight gain - a pilot study.

Hemodialysis patients are susceptible to excess volume accumulation, particularly over the 2-day interval (long interdialytic gap), resulting in higher interdialytic weight gain (IDWG). We thought to determine whether a novel device designed to enhance fluid and salt loss by activating the eccrine sweat glands can mitigate IDWG. Patients eligible for the study were undergoing regular hemodialysis for ≥3 months, without residual renal function, and with IDWG (as a percentage of IDWG/dry body weight) ≥2.5%. Treatments were administered at the patient's home. The primary performance endpoint was differences in weight gain over long interdialytic period with the device compared to the control period. Secondary exploratory endpoints included the need for ultrafiltration (UF) rate > 10 mL/kg/h in the post-interval dialysis. Five patients were enrolled into the pilot study (age range 26 to 69 years, 3 women). The hourly mean weight loss from sweat was 186 ± 45 g/h. The average procedure length was 4.5 h with an average fluid loss of 899 ± 283 grams per procedure. The average least-squares mean absolute difference of IDWG between the control and treatment periods was -2.0%; (95% confidence interval [CI], -2.9% to -1.2%, p < 0001). The reduction in IDWG was associated a reduction in UF rates, from 9.23 ± 3.7 mL/kg/h to 5.55 ± 2.45 mL/kg/h between the control and treatment periods (p < 0.001), resulting in a safe UF rate (<10 mL/kg/h) in all post-treatment sessions. We conclude that enhancing sweat rate can mitigate IDWG in hemodialysis patients.

Hemodialysis patients have signs of a chronic thrombotic burden.

BACKGROUND: Cardiovascular diseases are the dominant cause of morbidity in hemodialysis (HD) patients. Unless sufficient anticoagulation is used during HD, clotting may appear. The objective was to investigate if levels of fibrin degradation products (D-dimer) were increased before and during HD. METHODS: The combined observational study included 20 patients performing a total of 60 hemodialysis divided into three sessions of low-flux dialysis. None of the patients suffered from any clinically evident thromboembolic event before or during the study. Median bolus anticoagulation (mainly tinzaparin) doses were 84 Units/kg bow. Blood samples were drawn before HD (predialysis), and at 30min and 180min during HD with focus on analyzing D-dimer levels and its relation to interdialytic weight gain (IDWG) and speed of fluid elimination by HD (UF-rate). RESULTS: Predialysis, D-dimer levels (mean 0.767 ±0.821, min 0.136mg/L) were above the upper reference value in 95% of the sessions. D-dimer levels were lowered at 30min (p<0.001) and returned to predialysis levels at 180min. Predialysis D-dimer correlated with NT-pro-BNP, Troponin T, IDWG and UF-rate. Multiple regression analysis revealed that the D-dimer levels were significantly related to IDWG and the UF-rate. CONCLUSIONS: D-dimer levels were elevated in a high proportion predialysis and during HD and related to the IDWG and the UF-rate. Awareness of D-dimer levels and future studies will help clarify if optimization of those variables, besides anticoagulation and biocompatibility measures, will eradicate the repeated subclinical thromboembolic events related to each HD; one reason that may explain organ damage and shortened life span of these patients.

Interdialytic weight gain and low-salt diet in patients on chronic hemodialysis: A systematic review and meta-analysis.

OBJECTIVE: The present systematic review and meta-analysis aims to determine the difference in the interdialytic weight gain (IDWG) between low salt intake diet and normal/high salt intake diet or between nutritional counseling aimed at reducing diet salt intake and no nutritional counseling in patients on chronic hemodialysis. METHODS: Medline, PubMed, Web of Science, and the Cochrane Library were searched. Randomized, crossover or parallel studies and observational studies were considered for inclusion and: 1) included adult patients on chronic hemodialysis since at least 6 months; 2) compared normal salt intake diet with low salt intake diet on IDWG; 3) compared nutritional counseling aimed at reducing diet salt intake with no intervention on IDWG; 4) reported on IDWG. RESULTS: Eight articles (783 patients) were fully assessed for eligibility and included in the investigation. Meta-analysis showed frequencies of patients that increased their weight after dialysis more than 2.5 Kg (events) over total enrolled subjects for each group (control and experimental). As no significant heterogeneity was observed (I2 = 8%; p = 0.36), the pooled analysis was performed using a fixed-effect model. Funnel plot was generated and no obvious asymmetry was observed. The Overall Odds Ratio to get an event in the experimental group, in respect to controls, is 0.57 (0.33-0.97) (p = 0.04] with single studies OR ranging between 0.11 and 1.08. CONCLUSION: The present systematic review and meta-analysis suggest that the use of a low salt diet sodium or a nutritional counseling aimed at reducing diet salt intake is associated with a statistically significant reduction of the IDWG in patients on chronic hemodialysis.

Activation and disease control of patients on chronic hemodialysis: An observational study.

BACKGROUND AND OBJECTIVE: Patient activation is a concept that refers to the willingness to manage one's health and medical care. To assess it, a patient activation measure (PAM) has been developed and validated. Several studies report low activation in patients with chronic diseases. However, information on activation in hemodialysis patients is scarce. The aim of the present study is to describe the activation level of patients on chronic treatment in an HD unit and its relationship with disease control parameters. MATERIALS AND METHODS: Cross-sectional observational study in patients with advanced chronic kidney disease on chronic HD treatment. Ninety-six patients were included. Activation was measured with the PAM-13 questionnaire. Its relationship with descriptive variables (age, sex, comorbidity, studies, habitat) and disease control variables (vascular access, blood flow, potassaemia, phosphataemia, interdialytic gain) was studied. For this purpose, Spearman's correlation test, multiple linear regression model and logistic model were used as statistical methods. RESULTS: The mean (SD) PAM-13 score was 63.19 (15.21). Activation was significantly associated with vascular access (P = 0.003), blood flow (P = 0.024), and interdialytic gain of patients (P = 0.008). CONCLUSIONS: Activation in patients on chronic hemodialysis treatment is low. Higher activation is related having an arteriovenous fistula, higher blood flow and lower interdialytic gain. Future studies are needed to confirm and apply our results.

Once-per-week haemodialysis in a financial crisis: Predictors of interdialytic weight gain.

BACKGROUND: Several countries are experiencing challenges in maintaining standard haemodialysis services for people with kidney failure. OBJECTIVE: This study aimed to investigate the health profile of people receiving haemodialysis and to identify factors associated with interdialytic weight gain. DESIGN: A cross-sectional study. PARTICIPANTS: A total of 166 adults with kidney failure and receiving haemodialysis for at least 3 months were included. MEASUREMENTS: A structured chart audit form collected, demographic and haemodialysis treatment characteristics, recent biochemical and haematological results, and prescribed treatment regimens from clinical records. Data were analysed descriptively. Odds ratios (OR) were calculated to identify independent risk factors for interdialytic weight gain. RESULTS: Mean age was 52 years (SD = 12.5), over half were male (60.2%, n = 100), and most were receiving 4 h of haemodialysis once per week (87.3%, n = 145). Approximately half (51.8%, n = 86) had an interdialytic weight gain >2%. Being female (OR = 3.39; 95% CI, 1.51-7.61), increased comorbidities (OR = 1.50; 95% CI, 1.22-1.84) and having BMI outside of the normal range (overweight/obese [OR = 8.49; 95% CI, 3.58-20.13] or underweight [OR = 4.61; 95% CI, 1.39-15.31]) were independent risk factors for increased interdialytic weight gain. CONCLUSION: Most patients were receiving 4 h of haemodialysis once per week although only modest alterations in potassium, phosphate, and fluid status were observed. Understanding the patient profile and predictors of interdialytic weight gain will inform the development of self-management interventions to optimise clinician support.

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.

Interdialytic weight gain and low dialysate sodium concentration in patients on chronic hemodialysis: a systematic review and meta-analysis.

PURPOSE: The present systematic review and meta-analysis aimed at evaluating the effect of low dialysate sodium concentration on interdialytic weight gain (IDWG) in chronic hemodialysis patients. METHODS: Studies were eligible for inclusion if they were English language papers published in a peer-reviewed journal and met the following inclusion criteria: (1) studies in adult patients (over 18 years of age), (2) included patients on chronic hemodialysis since at least 6 months; (3) compared standard (138-140 mmol/l) or high (> 140 mmol/l) dialysate sodium concentration with low (< 138 mmol/l) dialysate sodium concentration; (4) Included one outcome of interest: interdialytic weight gain. Medline, PubMed, Web of Science, and the Cochrane Library were searched for the quality of reporting for each study was performed using the Quality Assessment Tool of Controlled Intervention Studies of the National Institutes of Health. The quality of reporting of each cross-over study was performed using the Revised Cochrane Risk of Bias (RoB) tool for cross-over trials as proposed by Ding et al. RESULTS: Nineteen studies (710 patients) were included in the analysis: 15 were cross-over and 4 parallel randomized controlled studies. In cross-over studies, pooled analysis revealed that dialysate sodium concentration reduced IDWG with a pooled MD of - 0.40 kg (95% CI - 0.50 to - 0.30; p < 0.001). The systematic review of four parallel, randomized, studies revealed that the use of a low dialysate sodium concentration was associated with a significant reduction of the IDWG in two studies, sustained and almost significant (p = 0.05) reduction in one study, and not significant reduction in one study. CONCLUSION: Low dialysate sodium concentration reduces the IDWG in prevalent patients on chronic hemodialysis.

Is increased subjective thirst associated with greater interdialytic weight gains, extracellular fluid and dietary sodium intake?

BACKGROUND: Some previous studies have reported an effect of increasing subjective thirst and interdialytic weight gains (IDWG), and that this may be influenced by nonadherence to dietary sodium restrictions, whereas others reported no such association. As such we wished to review the effect of self-reported thirst on IDWGs and dietary sodium intake. METHODS: Dialysis patients were asked to complete visual analogues thirst, distress thermometer (DT) scores and complete a sodium food frequency questionnaire (SFFQ). IDWG and pre and post dialysis volumes were measured with multifrequency bioelectrical impedance. RESULTS: One hundred and eleven patients completed the questionnaires and had bioimpedance measurements: 63% male, mean age 63.8 ± 16.1 years, 33% diabetic with a median thirst score 3 (0-5) and SFFQ 52.0 ± 18, and IDWG 2.1 ± 1.3%. Thirst was associated with DT (r = 0.28, p = 0.004) and negatively with age (r = -0.31, p < 0.001), but not SFFQ, IDWG, extracellular water, or dialysate sodium, or dialysate to plasma gradient. Patients with higher thirst scores were younger (58.0 ± 15.2 vs. 69.4 ± 15.0 years, p < 0.001) with higher DT scores (5 [2-7] vs. 2 [0-5], p < 0.001). On multivariate logistic analysis, only age was associated with self-reported thirst (odds ratio 0.95, 95% confidence limits 0.92-0.98, p < 0.001). CONCLUSION: We found that subjective thirst was greater for younger patients and those who reported higher levels of distress, but no association with IDWGs, dietary sodium intake, or dialysate sodium. However, most of our patients followed the dietary advice, as evidenced by the low SFFQ scores and % IDWGs. Whether thirst increases distress or distress increases subjective thirst remains to be determined.

Myocardial markers are highly altered by higher rates of fluid removal during hemodialysis.

INTRODUCTION: Although hemodialysis is lifesaving in patients with kidney failure extensive interdialytic weight gain (IDWG) between dialyses worsens the prognosis. We recently showed a strong correlation between IDWG and predialytic values of cardiac markers. The aim of the present study was to evaluate if the cardiac markers N-terminal pro-B-type natriuretic peptide (proBNP) and troponin T were influenced by IDWG and speed of fluid removal (ultrafiltration-rate). METHODS: Twenty hemodialysis patients performed in total 60 hemodialysis (three each). Predialytic values of proBNP and troponin T and changes from predialysis to 180 min hemodialysis (180-0 min) were compared with the IDWG calculated in percent of body weight. The ultrafiltration-rate was adjusted (UF-rateadj ) to IDWG: (100 × weight gain between dialysis [kg])/(estimated body dry weight [kg] × length of hemodialysis session [hours]). RESULTS: UF-rateadj correlated (Spearman) with (1) predialytic values of IDWG (r = 0.983, p < 0.001), proBNP (r = 0.443, p < 0.001), and troponin T (r = 0.296, p = 0.025); and (2) differences in proBNP180-0min (r = 0.572, p < 0.001) and troponin T180-0min (r = 0.400, p = 0.002). UF-ratesadj above a breakpoint of 0.60 caused more release of proBNP180-0min (p = 0.027). Remaining variables in multiple regression analysis with ProBNP180-0min as dependent factor were predialytic proBNP (p < 0.001) and the ultrafiltration-rate (p < 0.001). CONCLUSION: Higher UF-rateadj during dialysis was correlated to increased levels of cardiac markers. Data support a UF-rateadj lower than 0.6 to limit such increase. Further studies may confirm if limited fluid intake and a lower UF-rateadj should be recommended to prevent cardiac injury during dialysis.

Results of Salt Intake Restriction Monitored with the New Sodium Control Biosensor.

INTRODUCTION: Adherence to a low-sodium (Na) diet is crucial in patients under hemodialysis, as it improves cardiovascular outcomes and reduces thirst and interdialytic weight gain. Recommended salt intake is lower than 5 g/day. The new 6008 CAREsystem monitors incorporate a Na module that offers the advantage of estimating patients' salt intake. The objective of this study was to evaluate the effect of dietary Na restriction for 1 week, monitored with the Na biosensor. METHODS: A prospective study was conducted in 48 patients who maintained their usual dialysis parameters and were dialyzed with a 6008 CAREsystem monitor with activation of the Na module. Total Na balance, pre-/post-dialysis weight, serum Na (sNa), changes in pre- to post-dialysis sNa (ΔsNa), diffusive balance, and systolic and diastolic blood pressure were compared twice, once after 1 week of patients' usual Na diet and again after another week with more restricted Na intake. RESULTS: Restricted Na intake increased the percentage of patients on a low-Na diet (<85 Na mmol/day) from 8% to 44%. Average daily Na intake decreased from 149 ± 54 to 95 ± 49 mmol, and interdialytic weight gain was reduced by 460 ± 484 g per session. More restricted Na intake also decreased pre-dialysis sNa and increased both intradialytic diffusive balance and ΔsNa. In hypertensive patients, reducing daily Na by more than 3 g Na/day lowered their systolic blood pressure. CONCLUSIONS: The new Na module allowed objective monitoring of Na intake, which in turn could permit more precise personalized dietary recommendations in patients under hemodialysis.

Associations of interdialytic weight gain in the long intervals with mortality and residual kidney function decline.

INTRODUCTION: Interdialytic weight gain (IDWG) is crucial in the association between long interdialytic intervals and mortality in hemodialysis patients. The impact of IDWG on changes in residual kidney function (RKF) has not been evaluated thoroughly. This study examined the associations of IDWG in the long intervals (IDWGL) with mortality and rapid RKF decline. METHODS: This retrospective cohort study included patients who initiated hemodialysis in the United States dialysis centers from 2007 to 2011. IDWGL was defined as IDWG in the two-day break between dialysis sessions. This study examined the associations of seven categories of IDWGL (0% to <1%, 1% to <2%, 2% to <3% [reference], 3% to <4%, 4% to <5%, 5% to <6%, and ≥6%) with mortality using Cox regression models and rapid decline of renal urea clearance (KRU) using logistic regression models. The continuous relationships between IDWGL and study outcomes were investigated using restricted cubic spline analyses. FINDINGS: Mortality and rapid RKF decline were assessed in 35,225 and 6425 patients, respectively. Higher IDWGL categories were linked to increased risk of adverse outcomes. The multivariate adjusted hazard ratios (95% confidence intervals) of all-cause mortality for 3% to <4%, 4% to <5%, 5% to <6%, and ≥6% IDWGL were 1.09 (1.02-1.16), 1.14 (1.06-1.22), 1.16 (1.06-1.28), and 1.25 (1.13-1.37), respectively. The multivariate adjusted odds ratios (95% confidence intervals) of rapid decline of KRU for 3% to <4%, 4% to <5%, 5% to <6%, and ≥6% IDWGL were 1.03 (0.90-1.19), 1.29 (1.08-1.55), 1.17 (0.92-1.49), and 1.48 (1.13-1.95), respectively. When IDWGL exceeded 2%, the hazard ratios of mortality and the odds ratios of rapid KRU decline continuously increased. DISCUSSION: Higher IDWGL was incrementally associated with higher mortality risk and rapid KRU decline. IDWGL level over 2% was linked to higher risk of adverse outcomes. Therefore, IDWGL may be utilized as a risk parameter for mortality and RKF decline.

Sodium intake and urinary losses in children on dialysis: a European multicenter prospective study.

BACKGROUND: Sodium (Na) balance is unexplored in dialyzed children. We assessed a simplified sodium balance (sNaB) and its correlates in pediatric patients receiving maintenance dialysis. METHODS: Patients < 18 years old on hemodialysis (HD) or peritoneal dialysis (PD) in six European Pediatric Dialysis Working Group centers were recruited. sNaB was calculated from enteral Na, obtained by a 3-day diet diary, Na intake from medications, and 24-h urinary Na (uNa). Primary outcomes were systolic blood pressure and diastolic blood pressure standard deviation scores (SBP and DBP SDS), obtained by 24-h ambulatory blood pressure monitoring or office BP according to age, and interdialytic weight gain (IDWG). RESULTS: Forty-one patients (31 HD), with a median age of 13.3 (IQR 5.2) years, were enrolled. Twelve patients (29.3%) received Na-containing drugs, accounting for 0.6 (0.7) mEq/kg/day. Median total Na intake was 1.5 (1.1) mEq/kg/day, corresponding to 60.6% of the maximum recommended daily intake for healthy children. Median uNa and sNaB were 0.6 (1.8) mEq/kg/day and 0.9 (1.7) mEq/kg/day, respectively. The strongest independent predictor of sNaB in the cohort was urine output. In patients receiving HD, sNaB correlated with IDWG, pre-HD DBP, and first-hour refill index, a volume index based on blood volume monitoring. sNaB was the strongest predictor of IDWG in multiple regression analysis (ß = 0.63; p = 0.005). Neither SBP SDS nor DBP SDS correlated with sNaB. CONCLUSIONS: Na intake is higher than uNa in children on dialysis, and medications may be an important source of Na. sNaB is best predicted by urine output in the population, and it is a significant independent predictor of IDWG in children on HD. A higher resolution version of the Graphical abstract is available as Supplementary information.

Interdialytic weight gain is not associated with symptoms of depression or apathy in patients on chronic hemodialysis.

PURPOSE: Little is known about the relationships between apathy, depressive symptoms and interdialytic weight gain (IDWG) in patients on chronic hemodialysis. Aim of the present study is to investigate the association between IDWG and symptoms of depression and apathy in hemodialysis patients. METHODS: A total of 139 chronic patients of the HD units between January 2020 and December 2021 were included in the present cross-sectional study. IDWG was calculated as the difference between the pre-HD weight and the weight registered after the previous session; the average of the sessions in a month was registered. Apathy Evaluation Scale (AES) was adopted to evaluate apathy. Depression was assessed by Beck Depression Inventory (BDI). RESULTS: Ninety-three patients had IDWG% ≤ 4 and 46 had an IDWG% > 4. Correlation between IDWG% and BDI as well that between IDWG% and AES were not statistically significant. Median BDI and mean AES did not differ significantly between the groups. In addition, 104 patients had a BDI < 16 and 35 had a BDI ≥ 6. Seventy-five patients had an AES score ≤ 35 and 63 had a AES score > 35. The IDWG (kg) and the IDWG% did not differ significantly between the two groups. CONCLUSION: IDWG is not associated with symptoms of depression or apathy in hemodialysis patients. Thus, these results may question if the use of behavioral intervention aimed at improving motivation is warranted in the hemodialysis population to reduce the IDWG.

Low dialysate sodium in children and young adults on maintenance hemodialysis: a prospective, randomized, crossover study.

BACKGROUND: The optimal dialysate sodium concentration (dNa) in children on hemodialysis (HD) is unknown. The aim of this study was to compare the effect on interdialytic weight gain (IDWG) and blood pressure (BP) of a low (135 mmol/l) and standard dNa (138 mmol/l) in children and young adults on maintenance HD. METHODS: This prospective single-blind randomized crossover study consisted of a randomized sequence of two phases: "standard dNa" of 138 mmol/L and "low dNa" of 135 mmol/L. Each phase lasted 4 weeks. Inclusion criteria were age < 25 years, hypertension, pre-HD serum Na (sNa) ≥ 130 mmol/L, and occurrence of symptoms in less than 25% of sessions. Primary outcomes were pre-HD systolic and diastolic BP and IDWG. RESULTS: Fifteen patients were recruited, mean age 17.8 ± 4.4 years. Pre-HD SBP and DBP were not different between the two treatments. Mean IDWG was significantly lower with low dNa than with standard dNa: 2.12 ± 1.39% vs. 2.77 ± 1.53%, respectively (p = 0.008). The first-hour refill index (a volume index based on blood-volume monitoring) was significantly lower with dNa 135 mmol/L (p = 0.018). The mean Na gradient (dNa-sNa) was - 2.53 ± 2.4 mmol/L with dNa 135 mmol/L and 0.17 ± 2.8 mmol/L with dNa 138 mmol/L (p = 0.0001). The incidence of symptomatic sessions was similar (1.0% vs. 1.0%). CONCLUSIONS: In a selected population of hypertensive pediatric and young adult HD patients, a dNa of 135 mmol/L was associated with a significant reduction of IDWG compared with a dNa of 138 mmol/L. Furthermore, long-term studies are needed to investigate the effect of lowering dNa on BP. A higher resolution version of the Graphical abstract is available as Supplementary information.

Subjective Thirst in Relation to Interdialytic Weight Gain: A Systematic Review of Observational Studies.

INTRODUCTION: Hemodialysis (HD) patients are often prescribed salt and fluid-restricted diets to reduce their interdialytic weight gain (IDWG) and prevent chronic volume overload and hypertension. However, adherence to fluid restrictions is poor, which may be due to HD patients' excessive thirst. The purpose of the review is to explore the association between HD patients' subjective thirst and IDWG, which may inform strategies to manage chronic volume overload. METHODS: We conducted the literature search in Web of Science, Cumulative Index to Nursing and Allied Health Literature, PubMed, and the Cochrane Library, until February 25, 2019. Studies performing statistical tests to assess the association between patients' subjective thirst and IDWG were included. RESULTS: A total of eighteen studies were included in the systematic review, which measured the relationship between patients' subjective thirst and IDWG. Among them, 14 studies found that different domains of thirst and different units of IDWG are positively associated. Therefore, there is a positive association between the patients' subjective thirst and IDWG. However, the findings should be interpreted cautiously as there was variability in thirst and IDWG measurement techniques, which might influence the estimated relationship in these studies. DISCUSSION/CONCLUSION: These data suggest that strategies are needed to reduce thirst to control IDWG in HD patients.

Home-delivered meals as an adjuvant to improve volume overload and clinical outcomes in hemodialysis.

Patients on chronic hemodialysis are counseled to reduce dietary sodium intake to limit their thirst and consequent interdialytic weight gain (IDWG), chronic volume overload and hypertension. Low-sodium dietary trials in hemodialysis are sparse and mostly indicate that dietary education and behavioral counseling are ineffective in reducing sodium intake and IDWG. Additional nutritional restrictions and numerous barriers further complicate dietary adherence. A low-sodium diet may also reduce tissue sodium, which is positively associated with hypertension and left ventricular hypertrophy. A potential alternative or complementary approach to dietary counseling is home delivery of low-sodium meals. Low-sodium meal delivery has demonstrated benefits in patients with hypertension and congestive heart failure but has not been explored or implemented in patients undergoing hemodialysis. The objective of this review is to summarize current strategies to improve volume overload and provide a rationale for low-sodium meal delivery as a novel method to reduce volume-dependent hypertension and tissue sodium accumulation while improving quality of life and other clinical outcomes in patients undergoing hemodialysis.

Interdialytic weight gain and educational/cognitive, counseling/behavioral and psychological/affective interventions in patients on chronic hemodialysis: a systematic review and meta-analysis.

BACKGROUND: This work aimed to shed light on the notorious debate over the role of an educational/cognitive/behavioral or psychological approach in the reduction of interdialytic weight gain (IDWG) in patients on chronic hemodialysis. METHODS: Searches were run from 1975 to January 2022 on Medline, PubMed, Web of Science, and the Cochrane Library. The search terms included "hemodialysis/haemodialysis" AND "adherence" AND ("fluid intake" OR "water intake") AND ("weight gain" OR "interdialytic weight gain" OR "IDWG") AND "patient-level interventions. Randomized controlled studies were eligible if they were in English, published in a peer-reviewed journal and regarded adults patients with on chronic hemodialysis for at least 6 months; compared educational/cognitive and/or counseling/behavioral or psychological interventions to no intervention on interdialytic weight gain. Outcome of interest was interdialytic weight gain. The review was registered on the International Prospective Register of Systematic Reviews in Health and Social Care (PROSPERO, ID number CRD42022332401). RESULTS: Eighteen studies (1759 patients) were included in the analysis. Compared to the untreated group, educational/cognitive and/or counseling/behavioral interventions significantly reduced interdialytic weight gain with a pooled mean difference of - 0.15 kg (95% CI - 0.26, 30-0.05; P = 0.004). On the other hand, psychological/affective interventions reduced interdialytic weight gain with a pooled mean difference of - 0.26 kg (95% CI - 0.48, - 0.04; P = 0.020). CONCLUSIONS: Educational/cognitive, counseling/behavioral or psychological/affective interventions significantly reduced the interdialytic weight gain in patients on chronic hemodialysis, although such reduction did not appear to be clinically relevant on hard outcomes.

Effects of Standard and Individualized Dialysate Sodium in Chronic Hemodialysis Patients Upon Echocardiography Parameters.

Aims: This study assessed the effects of individualized dialysis sodium prescription on changes of echo-cardiography in hemodialysis (HD) patients. Methods: 77 chronic hemodialysis patients were analysed. In the first phase all patients underwent dialysis with standard dialysate sodium of 138 mmol/L followed by the second phase where dialysis was performed with individualized dialysate sodium concentration according to average pre HD serum sodium concentration. After the first phase, the subjects were divided into 3 groups: normotensive, hypertensive and hypotensive based on the average pre-HD systolic BP during the first phase. In all patients echocardiography was performed at the end of the first and second phase. Results: Patients had no statistical significant change in blood pressure compared with standard dialysate sodium, only statistical significant change in interdialytic weight gain (IDWG). By dividing the patients, sodium individualization resulted in significantly lower blood pressure and IDWG (p=0.018) in hyper-tensive patients, whereas normotensive patients showed only significant decrease in IDWG (p=0,004). Hypertensive patients had significant highest sodium gradient compared to other patients (p<0.05), followed by significant increase of 0,6% IDWG confirmed with univariate regression analysis. In all patients, echocardiography analysis showed an increase of 2.04 mm of LVDD by increasing the sodium gradient for 1 mmol/L and significantly increased LVM of 35.69 gr by 1 kg increase in IDWG. Conclusions: A reduction of the dialysate sodium concentration based on the pre HD serum sodium level of the patient, reduced the SBP, DBP and IDWG and decreased the volume overload upon the heart and consequently heart hypertrophy assessed by echocardiography.

Dynamics of Cardiac Autonomic Responses During Hemodialysis Measured by Heart Rate Variability and Skin Sympathetic Nerve Activity: The Impact of Interdialytic Weight Gain.

Background: Autonomic nervous regulation plays a critical role in end-stage kidney disease (ESKD) patients with cardiovascular complications. However, studies on autonomic regulation in ESKD patients are limited to heart rate variability (HRV) analysis. Skin sympathetic nerve activity (SKNA), which noninvasively reflects the sympathetic nerve activity, has not been used in ESKD patients. Methods: Seventy-six patients on maintenance hemodialysis (MHD) treatment (a 4-h HD session, three times a week) were enrolled. Utilizing a noninvasive, single-lead, high-frequency recording system, we analyzed the dynamic change in HRV parameters and SKNA during HD. The different characteristics between the subgroups divided based on interdialytic weight gain (IDWG, <3 kg or ≥3 kg) were also demonstrated. Results: After the HD, values for heart rate (75.1 ± 11.3 to 80.3 ± 12.3 bpm, p < 0.001) and LF/HF (1.92 ± 1.67 to 2.18 ± 2.17, p = 0.013) were significantly higher than baseline. In subgroup analysis, average voltage of skin sympathetic nerve activity (aSKNA) in IDWG ≥3 kg group was lower than the IDWG <3 kg group at the end of MHD (1.06 ± 0.30 vs 1.32 ± 0.61 µV, p = 0.046). Moreover, there was a linear correlation between mean heart rate (HR) and aSKNA in low IDWG patients (p < 0.001), which was not found in high IDWG patients. At the 1-year follow-up, high IDWG patients had a higher incidence of cardiovascular hospitalization (p = 0.046). Conclusions: In MHD patients, a gradual activation of sympathetic nerve activity could be measured by HRV and aSKNA. A lower aSKNA at the end of HD and a loss of HR-aSKNA correlation in overhydrated patients were observed. Extensive volume control is promising to improve the autonomic nervous function and clinical outcomes in this population.

Effects of Electrical Stimulation of Acupoints on Xerostomia for Patients Who Undergo Hemodialysis.

Xerostomia plays a major role in higher interdialytic weight gain (IDWG), which causes cardiovascular complications in patients who undergo hemodialysis. However, few studies have determined a method to manage xerostomia. This study determines the effect of transcutaneous electrical acupoint stimulation (TEAS) on hemodialysis patients with xerostomia and the percentage of IDWG. The study was a single-blind and quasi-experimental study. There are 75 participants: 37 in the TEAS group and 38 in the contrast group. The TEAS group used 250 µs and 50 Hz and the contrast group used 50 µs and 2 Hz three times a week for 3 weeks to stimulate ST 6 and TE17 acupoints. The salivary flow rates, dry mouth, and %IDWG were determined before, during and one week after the program. Compared with the contrast group, the TEAS group showed a significantly improved salivary flow rate (mL/min) (F (2, 123) = 15.28, p < 0.0001), and patients recovered their normal salivary flow rate. However, the results show that both groups showed significant improvement in dry mouth after treatment. The TEAS group demonstrated no effect in terms of %IDWG, as expected. The results show that a TEAS program is an effective means of symptom management for xerostomia patients who undergo hemodialysis. A TEAS program can be used to manage symptoms for xerostomia patients who undergo hemodialysis.