Fellows' Forum in Dialysis: Interdialytic Weight Gain: Implications in Hemodialysis Patients

The effect of education given to hemodialysis patients based on the Roy Adaptation Model on fluid management, symptom control, and quality of life

This study aimed to determine the effect of fluid management, symptom control, and quality of life on education based on the Roy Adaptation Model. This randomized controlled study was conducted with the participation of 107 patients (53 intervention, 54 control). Data were collected using the "Patient Data Collection Form," "Fluid Control in Hemodialysis Patients Scale," "Dialysis Symptom Index," and "Nottingham Health Profile." The forms were filled out through face-to-face interviews with the patients in the intervention and control groups at the 0th (onset), 1st, and 3rd months. The patients in the intervention group were trained with an education booklet based on the Roy Adaptation Model. The results revealed that the education given according to the Roy Adaptation Model improved the compliance with fluid control, quality of life, and symptom control of hemodialysis patients. It is recommended that education based on the Roy Adaptation Model be systematically used by hemodialysis nurses. The results are limited to the population included in the study, and further research on hemodialysis populations is needed.

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.

Use of non-invasive intracranial pressure pulse waveform to monitor patients with End-Stage Renal Disease (ESRD)

End-stage renal disease (ESRD) is treated mainly by hemodialysis, however, hemodialysis is associated with frequent complications, some of them involve the increased intracranial pressure. In this context, monitoring the intracranial pressure of these patients may lead to a better understanding of how intracranial pressure morphology varies with hemodialysis. This study aimed to follow-up patients with ESRD by monitoring intracranial pressure before and after hemodialysis sessions using a noninvasive method. We followed-up 42 patients with ESRD in hemodialysis, for six months. Noninvasive intracranial pressure monitoring data were obtained through analysis of intracranial pressure waveform morphology, this information was uploaded to Brain4care® cloud algorithm for analysis. The cloud automatically sends a report containing intracranial pressure parameters. In total, 4881 data points were collected during the six months of follow-up. The intracranial pressure parameters (time to peak and P2/P1 ratio) were significantly higher in predialysis when compared to postdialysis for the three weekly sessions and throughout the follow-up period (p<0.01) data showed general improvement in brain compliance after the hemodialysis session. Furthermore, intracranial pressure parameters were significantly higher in the first weekly hemodialysis session (p<0.05). In conclusion, there were significant differences between pre and postdialysis intracranial pressure in patients with ESRD on hemodialysis. Additionally, the pattern of the intracranial pressure alterations was consistent over time suggesting that hemodialysis can improve time to peak and P2/P1 ratio which may reflect in brain compliance.

Dialysis-specific factors and incident atrial fibrillation in hemodialysis patients

Background

Atrial fibrillation (AF) is common in end-stage renal disease patients. Besides the traditional risk factors, we aimed to find dialysis-specific factors for developing incident AF.

Methods

From March 2017 to August 2018, we retrospectively reviewed all outpatient-based prevalent hemodialysis patients in our artificial kidney room, and they were followed up until August 2019. Dialysate calcium concentration (3 versus 2.5 mEq/L), time length (4 versus 3.5 h), frequency (thrice weekly versus twice weekly), dialyzer size (effective surface area of 1.4 m² versus 1.8 m²), membrane permeability (high flux versus low flux), ultrafiltration rate (mL/kg/hour), and blood flow rate (mL/min) were evaluated.

Results

Among a total of 84 patients, 15 (17.9%) had newly detected AF with a follow-up period of 21 (13.3–24) months. By performing multivariate Cox regression analysis, blood flow rate (mL/min) and ultrafiltration rate (mL/kg/h) were considered significant factors for developing incident AF (adjusted hazard ratio [HR], 0.977; p = 0.011 and adjusted HR, 1.176; p = 0.013, respectively), while dialysis bath, time length, and frequency, dialyzer size, and membrane type were not considered significant factors. Ultrafiltration cutoff rate of 8.6 mL/kg/h was the best predictive factor for incident AF (area under the curve-receiver operating characteristic [AUC-ROC], 0.746; p < 0.005), while blood flow rate was not considered a significant factor for incident AF in ROC analysis (AUC-ROC, 0.623; p = 0.126). Ultrafiltration rate was largely dependent on interdialytic weight gain (p < 0.005, linear-by-linear association).

Conclusion

Higher ultrafiltration rate was associated with incident AF in hemodialysis patients.

Evaluation of one year of frequent dialysis on fluid load and body composition using calf bioimpedance technique

OBJECTIVE

The primary aim of this study was to evaluate the effect of increased frequency of dialysis (FHD) on change in fluid status and body composition using segmental bioimpedance.

APPROACH

Twelve stable HD patients were switched from 3 times/week to 6 times/week HD (FHD). Systolic blood pressure (SBP), body mass and body mass index (BMI) were measured pre- and post-HD. Calf resistance (R ₅) at 5 kHz was measured using a multifrequency bioimpedance device (Hydra 4200). Calf resistivity (ρ  =  R ₅ * area/length), normalized resistivity (CNR  =  ρ/BMI) and calf extracellular volume (cECV) were calculated. Fat mass was measured by Futrex body composition analyzers (Futrex 6100, Futrex Tech, Inc.). All measurements were performed at baseline (BL) and monthly for up to one year.

MAIN RESULTS

Nine patients completed one year of FHD. Compared to BL, body weight and cECV decreased, and CNR increased significantly by the first month but did not change thereafter. SBP pre-HD decreased significantly by the end of the first month with further reduction until month 12. Additionally, antihypertensive medication decreased significantly from baseline by month 4 and remained stable from month 6 throughout the rest of the study. The post-HD CNR in five of nine patients reached the range of normal (>18.5 10^-2 * Ohm * m³ kg^-1 for males and  >19.1 10^-2 * Ohm * m³ kg^-1 for females) after 1 year FHD. In patients who returned to 3 times/week dialysis, CNR decreased significantly in the first week, and this was associated with increases in body weight and SBP.

SIGNIFICANCE

Reduction of fluid overload with no alteration of body composition was observed in this study. Accordingly, improving fluid status was confirmed by reducing BP and use of antihypertensive drugs together with increase in CNR. Measurement of fluid status by CNR in hemodialysis patients is a new method to quantitatively assess hydration potentially creating a target for volume of fluid removal.

Clinical trial for the control of water intake of patients undergoing hemodialysis treatment

Objective:

to analyze the impact of an educational and motivational intervention for patients with a chronic kidney disease, undergoing hemodialysis treatment, on the control of fluid intake during interdialytic periods.

Method:

a quasi-experimental, non-randomized clinical trial with patients from a Nephrological Unit of the State of São Paulo. Participants were included in two groups: Control Group with 106 patients and Intervention Group with 86 patients, totaling 192 participants. The used intervention was an educational and motivational video to control liquid intake, based on the Bandura’s Theory. The measure of control of water intake was the percentage of lost weight, also considered the variable outcome of the research. For the data analysis, descriptive analyses and regression analysis of the Inflated Beta Model were used.

Results:

patients who participated in the intervention had a decrease in the pattern of weight gain in interdialytic periods, with a 3.54 times more chance of reaching the goal of 100% of weight loss when compared to participants from the control group.

Conclusion:

the educational and motivational intervention was effective in reducing the percentage of weight loss in patients undergoing hemodialysis. Brazilian Clinical Trials Registry (ReBEC) under the opinion RBR-4XYTP6.

Association of Ultrafiltration Rate with Mortality in Incident Hemodialysis Patients

BACKGROUND/AIMS

Ultrafiltration rate (UFR) appears to be associated with mortality in prevalent hemodialysis (HD) patients. However, the association of UFR with mortality in incident HD patients remains unknown.

METHODS

We examined a US cohort of 110,880 patients who initiated HD from 2007 to 2011. Baseline UFR was divided into 5 groups (<4, 4 to <6, 6 to <8, 8 to <10, and ≥10 mL/h/kg body weight [BW]). We examined predictors of higher baseline UFR using logistic regression and the association of baseline UFR and all-cause and cardiovascular (CV) mortality using Cox proportional hazard models with adjustments for demographics, comorbidities, and markers of malnutrition-inflammation-cachexia syndrome.

RESULTS

Patients were 63 ± 15 years, with 43% women, 32% African Americans, and had a mean baseline UFR of 7.5 ± 3.1 mL/h/kg BW. In the fully adjusted logistic regression models, factors associated with higher UFR (≥7.5 mL/h/kg BW) included Hispanic ethnicity, diabetes, and higher dietary protein intake. There was a linear association between UFR and all-cause and CV mortality, where UFR ≥10 mL/h/kg BW (reference UFR 6-<8 mL/h/kg BW) conferred the highest risk in both unadjusted (HR 1.15 [95% CI 1.10-1.19]) and adjusted models (HR 1.23 [95% CI 1.16-1.31]). The linear association with all-cause mortality remained consistent across strata of age, urine volume, and treatment time.

CONCLUSIONS

Higher UFR is independently associated with higher all-cause and CV mortality in incident HD patients. Clinical trials are warranted to examine the effects of lowering UFR on outcomes.

Revisiting Interdialytic Weight Gain and Mortality Association With Serum Albumin Interactions: The Japanese Dialysis Outcomes and Practice Pattern Study

BACKGROUND

The dialysis practice guideline in Japan sets a limit on the allowed interdialytic weight gain (IDWG) <6%. However, the effects of relative gain of fluid volume to body weight may differ in presence of morbid conditions. Here, we examined whether or not the associations between IDWG and mortality differ by serum albumin (sAlb), a nutritional and illness marker.

DESIGN

The study type used was prospective cohort study.

SUBJECTS

Patients who participated in the Japan Dialysis Outcomes and Practice Pattern Study (phase 1-4 [1999-2011]) and received thrice-weekly hemodialysis.

METHODS

IDWG was the exposure of interest and was collected every 4 months, divided into 7 categories as follows: <2%, 2% to 3%, 3% to 4% (reference), 4% to 5%, 5% to 6%, 6% to 7%, and >7%. sAlb was treated as both an effect modifier and confounder and dichotomized into ≥3.8 g/dL and <3.8 g/dL segments, according to the protein-energy wasting criteria proposed by the International Society of Renal Nutrition and Metabolism.

MAIN OUTCOME MEASURE

The outcome in this study was all-cause mortality.

RESULTS

A total of 8,661 patients were analyzed. Time-varying Cox regression analyses revealed that, when sAlb was ≥3.8 g/dL, an IDWG >7% was associated with greater risk of mortality (adjusted hazard ratio [AHR] 2.74; 95% confidence interval [CI], 1.49-5.05). When sAlb was <3.8 g/dL, however, IDWGs <2% (AHR 1.89; 95% CI, 1.50-2.39) and 4% to 5% (AHR 0.75; 95% CI, 0.58-0.96) were associated with mortality (P for interaction = .001). Cubic spline analyses showed that the mortality increased when IDWG exceeded 6% for patients with sAlb ≥3.8 g/dL; in contrast, for patients with sAlb <3.8 g/dL, the mortality increased when IDWG was <3% and decreased when IDWG was between 4% and 6%.

LIMITATION

The main limitation was possible residual confounding.

CONCLUSIONS

The direction and magnitude of the associations between IDWG and mortality were modified by sAlb. Dialysis experts should take these results into account when revising the clinical practice guidelines.

Blood pressure and cardiovascular mortality in dialysis patients with left ventricular systolic dysfunction

BACKGROUND

In patients chronically treated with hemodialysis, the prevalence of heart failure is high with a consequently poor prognosis. The role played by blood pressure (BP) on cardiovascular (CV) mortality of these patients has not been clearly defined.

METHODS

In this follow-up study, we investigated the relationship of pre- and postdialysis measurements of BP with CV and all-cause mortality in a cohort of 557 dialysis patients with a left ventricular (LV) ejection fraction <50%.

RESULTS

During the follow-up (mean = 21.6 ± 8.8 months), 179 deaths were recorded. Ninety-eight patients died from CV causes. By the Cox multivariable analysis, we constructed a predictive model of CV mortality including age, duration on dialysis, diabetes, serum albumin, diffusive dialysis technique, predialysis mean arterial pressure (MAP) (hazard ratio (HR) = 0.978; 95% confidence interval (CI) = 0.956-0.999), and postdialysis MAP (HR = 1.035; 95% CI = 1.010-1.061). The relationship with mortality was inverse for predialysis MAP and direct for postdialysis MAP. In a subsequent analysis, we found that pre- and postdialysis systolic BP, but not diastolic BP, were predictive of CV mortality. Predialysis MAP was in a direct relationship with body mass index. Postdialysis MAP had an inverse relationship with weight loss during dialysis session.

CONCLUSIONS

CV mortality in dialysis patients with LV dysfunction is associated with both pre- and postdialysis BP interacting in a complex relationship. Nutritional state and fluid balance and removal are possible clues to this relationship.

Diverse effects of interdialytic intervals on central wave augmentation in haemodialysis patients

BACKGROUND

Increased arterial stiffness is a common finding and independent predictor of mortality in end-stage renal disease (ESRD) patients. A long interdialytic interval was associated with increased risk of cardiovascular death in patients receiving conventional haemodialysis (HD). This is the first study to examine the effects of a long (3-day) versus short (2-day) interdialytic period on arterial elasticity in HD patients.

METHODS

Seventy ESRD patients receiving standard HD three times per week were studied at the start and end of a 3-day and a 2-day interdialytic interval. At each time point, applanation tonometry of peripheral arteries was performed to assess arterial stiffness and wave reflection parameters. Aortic and brachial pulse wave velocities (PWV) were recorded as measures of arterial stiffness and augmentation index (AIx) as a measure of wave reflections.

RESULTS

AIx, heart-rate-adjusted AIx and augmentation pressure were significantly increased during both interdialytic intervals, whereas aortic and brachial PWVs remained unchanged. The interdialytic increases in all the three AIx parameters were significantly higher during the 3-day interval in comparison to the 2-day interval (P < 0.001 for all comparisons). In contrast, no significant differences in interdialytic changes of aortic (P = 0.355) and brachial (P = 0.319) PWVs were noted between the two intervals. Mixed linear model analysis revealed that central aortic systolic blood pressure (SBP) and body weight, but not aortic or brachial PWV, were independent determinants of the change in heart-rate-adjusted AIx throughout the study.

CONCLUSIONS

AIx is increased between HD sessions, whereas arterial elasticity is not. This interdialytic increase in central wave augmentation is more pronounced during the 3-day interval, suggesting a mechanism possibly involved in the elevated cardiovascular risk of HD patients at this time point.

Magnitude of end-dialysis overweight is associated with all-cause and cardiovascular mortality: a 3-year prospective study

BACKGROUND

We hypothesized that the difference between the prescribed end-dialysis body weight, defined end-dialysis over-weight (edOW; kg), and the body weight which is actually attained could impact survival in hemodialysis (HD) patients. The aim of this prospective observational study was to evaluate if edOW could influence survival in a cohort of prevalent HD patients, controlled for multiple dialysis and clinical risk factors and followed for 3 years.

METHODS

One hundred and eighty-two patients (117 men, age 65 ± 13 years) on regular HD treatment for at least 6 months [median 48 months (range: 6-366)] were followed from January 1, 2008 to December 31, 2010. Eighty-four patients (46%) did not achieve their prescribed dry body weight (dBW); their median edOW was 0.4 kg (range: 0.1-1.4). Ninety-eight died during observation, mainly from cardiovascular reasons (69%). Multivariate Cox regression analysis was utilized to evaluate the effect edOW, ultrafiltration rate (UFR), interdialytic weight gain (IDWG), age, sex, dialytic vintage, cardiovascular disease, antihypertensive therapy, diabetes, duration of HD, dBW, BMI, mean arterial blood pressure, Kt/V, and protein catabolic rate (PCRn) had on mortality.

RESULTS

Age (HR: 1.04; CI: 1.03-1.05; p <0.0001), IDWG (HR: 2.62; CI: 2.06-3.34; p < 0.01), UFR (HR: 1.13; CI: 1.09-1.16; p< 0.01), PCRn (HR: 0.02; CI: 0.01-0.04; p <0.001), and edOW (HR: 2.71; CI: 1.95-3.75; p < 0.02) were independently correlated to survival. The relative receiver operating characteristic curve identified a cutoff value of 0.3 kg for edOW in predicting death.

CONCLUSIONS

High edOW is independently associated with an increased long-term risk of all-cause and cardiovascular mortality in HD patients. Better survival was observed in patients with edOW <0.3 kg. For patients with higher edOW, longer or more frequent dialysis sessions should be considered in order to prevent the deleterious consequences of excessive body fluid expansion.

Trends in the incidence of atrial fibrillation in older patients initiating dialysis in the United States

BACKGROUND

One sixth of US dialysis patients 65 years of age have been diagnosed with atrial fibrillation/flutter (AF). Little is known, however, about the incidence of AF in this population.

METHODS AND RESULTS

We identified 258 605 older patients (≥67 years of age) with fee-for-service Medicare initiating dialysis in 1995 to 2007, who had not been diagnosed with AF within the previous 2 years. Patients were followed for newly diagnosed AF. Multivariable proportional hazard regression was used to examine temporal trends and associations of race and ethnicity with incident AF. We also studied temporal trends in the mortality and risk of ischemic stroke after new AF. Over 514 395 person-years of follow-up, 76 252 patients experienced incident AF for a crude AF incidence rate of 148/1000 person-years. Incidence of AF increased by 11% (95% confidence interval, 5-16) from 1995 to 2007. Compared with non-Hispanic whites, blacks (-30%), Asians (-19%), Native Americans (-42%), and Hispanics (-29%) all had lower rates of incident AF. Mortality after incident AF decreased by 22% from 1995 to 2008. Even more pronounced reductions were seen for incident ischemic stroke during these years.

CONCLUSIONS

The incidence of AF is high in older patients initiating dialysis in the United States and has been increasing over the 13 years of study. Mortality declined during that time but remained >50% during the first year after newly diagnosed AF. Because data on warfarin use were not available, we were unable to study whether trends toward better outcomes could be explained by higher rates of oral anticoagulation.

International differences in hemodialysis delivery and their influence on outcomes

There are many variations in the delivery of hemodialysis. These variations include components of conventional dialysis, such as membrane type, dialysis dose, and session duration. In addition, alternative approaches to dialysis, such as hemodiafiltration, nocturnal hemodialysis, and short daily hemodialysis, also may be considered. For some of these practice variations, data exist to support one approach over another (eg, fistulas rather than grafts and catheters), but for many, no such data exist. Very few practice variations have been examined in randomized trials, and we are reliant predominantly on observational data. This review examines some practice variations in hemodialysis delivery, attempting to highlight which of these may be appropriate to consider when optimizing dialysis delivery in the clinic.

Relationship between beliefs regarding a low salt diet in chronic renal failure patients on dialysis

OBJECTIVE

The aim of this study was to investigate the relationship between beliefs regarding a low salt diet and the nutritional behavior of sodium consumption as well their relation with sociodemographic and clinical variables among chronic renal failure (CRF) patients on dialysis.

DESIGN AND METHODS

This cross-sectional study enrolled a sample of 117 patients who answered the Brazilian version of the Beliefs about Dietary Compliance Scale (BDCS), the sodium frequency food questionnaire, and the use of discretionary salt/day.

RESULTS

The average of total salt consumption was 10.6 g/day (±6.3) and it was positively correlated with the interdialytic weight gain (r = 0.20 P = .032) and negatively correlated with the education level (r = -0.19 P = .044). The Benefits beliefs were discriminatory of the higher and lower salt consumers, and proportionally related to monthly income (r = 0.22 P = .017). The Barriers beliefs were positively correlated only to time on dialysis (r = 0.25 P = .008). Subjects with lower schooling and those of older age tended to consume more discretionary salt (r = -0.27, P = .005; r = 0.23, P = .016, respectively); however, they reported a lower consumption of foods with high salt content (r = 0.25 P = .006; r = -0.27 P = .004).

CONCLUSIONS

Educational interventions aimed at reducing salt consumption for this group must include interventions targeted at different behaviors related to overall salt consumption, the specificities of age, and level of schooling of the patients.

Prescription of antihypertensive agents to haemodialysis patients: time trends and associations with patient characteristics, country and survival in the DOPPS

BACKGROUND

Haemodialysis patients were studied in 12 countries to identify practice patterns of prescription of antihypertensive agents (AHA) associated with survival.

METHODS

The sample included 28 513 patients enrolled in DOPPS I and II. The classes of AHA studied were beta blocker (BB), angiotensin-converting enzyme inhibitor (ACEI), angiotensin receptor blocker (ARB), peripheral blocker, central antagonist, vasodilator, long-acting dihydropyridine calcium channel blocker (CCB), short-acting dihydropyridine CCB and non-dihydropyridine CCB. To reduce bias due to unmeasured confounders, the associations with mortality were assessed by separate Cox models based on patient-level prescription and facility prescription practice.

RESULTS

An increase in prescription of ARBs (9.5%) and BBs (9.1%) was observed from DOPPS I to II. Prescription of AHA classes varied significantly by country, ranging for BBs from 9.7% in Japan to 52.7% in Sweden and for ARBs from 5.5% in Italy to 21.3% in Japan in DOPPS II. Facilities that treated 10% more patients with ARBs had, on average, 7% lower all-cause mortality, independent of patient characteristics and the prescription patterns of other antihypertensive medications (P = 0.05). Significant and independent associations with reduction in cardiovascular mortality were observed for ARBs (RR = 0.79; P = 0.005) and BBs (RR = 0.87, P = 0.004) in analyses of patient-level prescriptions. These associations in the facility-level model followed the same direction.

CONCLUSIONS

DOPPS data show large variations across countries in AHA prescription for haemodialysis patients. The data suggest an association between ARB use and reduction in all-cause mortality, as well as with the use of BBs and reduction in cardiovascular mortality among haemodialysis patients.

Retinoblastoma: from disease to discovery

Retinoblastoma has contributed much to the understanding of cancer. It provided the classic 'two-hit model' for oncogenesis and helped to identify the first tumor suppressor gene RB1. Thirty years since then, the search for additional events underlying disease progression continues. Phenotypic variations in retinoblastoma offer numerous clues to disease pathogenesis. Understanding their molecular biological basis will provide insight into mechanisms underlying tumor progression. These not fully understood genetic and stochastic events play a major role in uncontrolled retinal precursor cell proliferation. Comparative genomic hybridization and gene expression studies have facilitated probing of genes controlling basic events in cellular development, i.e. proliferation, differentiation and apoptosis. Research to determine the cell of origin that underlies the evolution of retinoblastoma can lead to understanding of the stochastic events underlying the genesis of this cancer, which currently remains unclear. In this review, we discuss the recent developments in retinoblastoma and describe how they are beginning to shape a new and revised picture of retinoblastoma pathogenesis and progression.

Relationship between interdialytic weight gain and nutritional markers in younger and older hemodialysis patients

OBJECTIVE

Our objective was to investigate the correlations of interdialytic weight gain (IDWG) with the Malnutrition Inflammation Score (MIS) and other nutritional markers, especially when age difference is considered.

DESIGN

This was a cross-sectional study.

SETTING

The setting was an outpatient hemodialysis (HD) center in a community hospital.

PATIENTS

Excluding those with obvious inflammatory diseases, hospitalizations, and major surgery within the preceding 3 months, we enrolled all anuric patients who had undergone maintenance hemodialysis three times a week for >1 year. In total, 84 women and 80 men were enrolled. Their age (mean +/- SD) was 57.9 +/- 13.0 years.

MAIN OUTCOME MEASURES

The conditions of food intake and nutritional status were evaluated with MIS items. Concerning IDWG, the average of 12 sessions within 4 weeks was used. The relative IDWG (RIDWG) was calculated as IDWG divided by the respective dry weight. Other laboratory data were obtained from routine monthly sampling.

RESULTS

Whereas IDWG and RIDWG had no significant correlation with any of the MIS items in younger patients (<65 years old; n = 106), RIDWG had a positive correlation with the severity of insufficient food intake, gastrointestinal upset, functional incapacity, and wasting of muscle and subcutaneous fat in older patients (>/=65 years old; n = 58). On the other hand, IDWG and RIDWG had no significant correlation with serum albumin level in younger and older HD patients, respectively.

CONCLUSIONS

Our findings suggest that in older HD patients, the greater that the RIDWG is, the poorer the nutritional status will be. However, there is still controversy regarding IDWG and RIDWG as nutritional markers in HD patients.

Revisiting the dialysate sodium prescription as a tool for better blood pressure and interdialytic weight gain management in hemodialysis patients

Hypertension and chronic volume overload are complications often seen in hemodialysis patients. Current hemodialysis practices adopt a standard dialysate sodium prescription that is typically higher than the plasma sodium concentration of most patients. As a general rule, hemodialysis patients have stable predialysis plasma sodium concentrations, and each patient has a fixed "osmolar set point." Hypertonic dialysate sodium prescriptions, including sodium modeling, predispose to positive sodium balance and lead to higher blood pressure and increased interdialytic weight gain. Conversely, lowering or individualizing dialysate sodium reduces thirst, interdialytic weight gain, and blood pressure in non-hypotension prone dialysis patients. Optimization of the dialysate sodium prescription is an important step in achieving sodium balance and improving blood pressure control in hypertensive hemodialysis patients.

Association between high ultrafiltration rates and mortality in uraemic patients on regular haemodialysis. A 5-year prospective observational multicentre study

BACKGROUND

High ultrafiltration rate on haemodialysis (HD) stresses the cardiovascular system and could have a negative effect on survival.

METHODS

The effect of ultrafiltration rate (UFR; ml/h/kg BW) on mortality was prospectively evaluated in a cohort of 287 prevalent uraemic patients in regular HD from 1 January 2000 to 31 December 2005.

PATIENTS

165 men and 122 women, age 66 +/- 13 years, on regular HD for at least 6 months, median: 48 months (range 6-372 months). Mean UFR was 12.7 +/- 3.5 ml/h/kg BW, Kt/V: 1.27 +/- 0.13, body weight (BW): 62 +/- 13 kg, PCRn: 1.11 +/- 0.20 g/kg/day, duration of dialysis: median 240 min (range 180-300 min), mean arterial blood pressure (MAP) 99 +/- 9 mm/Hg. One hundred and forty nine patients (52%) died, mainly for cardiovascular reasons (69%). Multivariate Cox regression analysis was utilized to evaluate the effect on mortality of UFR, age, sex, dialytic vintage, cardiovascular disease (CVD), diabetes, dialysis modality, duration of HD, BW, interdialytic weight gain (IWG), body mass index (BMI), MAP, pulse pressure (PP), Kt/V, PCRn.

RESULTS

Age (HR 1.06; CI 1.04-1.08; P < 0.0001), PCRn (HR 0.17, CI 0.07-0.43; P < 0.0001), diabetes (HR 1.81, CI 1.24-2.47; P = 0.007), CVD (HR 1.86; CI 1.32-2.62; P = 0.007) and UFR (HR 1.22; CI 1.16-1.28; P < 0.0001) were identified as factors independently correlated to survival. We estimated the discrimination potential of UFR, evaluated at baseline, in predicting death at 5 years, calculating the relative receiver operating characteristic (ROC) curves and the cut-off that minimizes the absolute difference between sensitivity and specificity.

CONCLUSIONS

High UFRs are independently associated with increased mortality risk in HD patients. Better survival was observed with UFR < 12.37 ml/h/kg BW. For patients with higher UFRs, longer or more frequent dialysis sessions should be considered in order to prevent the deleterious consequences of excessive UFR.

Fluid Dynamics During Hemodialysis in Relationship to Sodium Gradient Between Dialysate and Plasma

Fluid shifts during hemodialysis involve changes in both extracellular and intracellular volumes. This study aimed to determine the effect of intradialytic sodium gradients (GNa), that is, the difference between dialysate and serum sodium concentration, on dynamics of extracellular and intracellular volumes in a group of maintenance hemodialysis patients. Extracellular volume change (deltaECV) between predialysis and postdialysis periods was determined by whole-body bioimpedance spectroscopy; intracellular volume change (deltaICV) was indirectly derived as the difference between deltaECV and the change in body weight, corrected for intradialytically given fluids. A total of 200 bioimpedance measurements were performed in 32 dialysis patients. Extracellular and intracellular volume changes were -2.6 +/- 0.9 L (range: -4.7 to -0.5 L) and -0.2 +/- 0.7 L (range: -2.5 to +1.5 L), respectively. There was a significant correlation between deltaICV and GNa; deltaICV = -0.12 * GNa + 0.26 (p < 0.001). In contrast, GNa was not correlated with deltaECV. We conclude that the sodium gradient between dialysate and plasma has a significant effect on the ICV during dialysis. Hemodialysis with GNa = 0 mmol/L should be sought to prevent ICV shrinking or swelling and to prevent excessive thirst, consequently high interdialytic weight gains, and ultrafiltration rates.