Effects of three times weekly eight-hour nocturnal hemodialysis on volume and nutritional status.

BACKGROUND: This prospective cohort study compared the changes in body water composition and nutritional parameters measured with multifrequency bioimpedance analysis between 8-hour three times weekly nocturnal hemodialysis (NHD) and 4-hour conventional hemodialysis (CHD) patients. PATIENTS AND METHODS: 55 patients on CHD and 57 patients on NHD were included in the study. Multifrequency bioimpedance analysis was performed at baseline and at the 12th month. The primary outcomes of the study were changes in extracellular water (ECW), fat mass, dry lean mass and phase angle. Secondary outcomes of the study included changes in blood pressure and biochemical parameters related to nutrition and inflammation. RESULTS: ECW/height values decreased in the NHD group, while they increased in the CHD group. Fat mass, dry lean mass, and serum albumin increased and high sensitive CRP decreased in the NHD group but did not change in the CHD group. When changes in parameters from baseline to the 12th month between the groups were compared, NHD was associated with improvement in volume parameter including ECW/height (difference -0.44 l/m, p < 0.001). Change in blood pressure was not different between the groups, however requirement for antihypertensive medication decreased from 26.5 to 8.5% in the NHD group (p = 0.002). NHD was also associated with increases in fat mass (difference 1.8 kg, p < 0.001), dry lean mass (difference 0.6 kg, p = 0.006), serum albumin (difference 0.19 g/dl, p < 0.001) and cholesterol (difference 18.8 mg, p < 0.001). Phase angle values decreased in the CHD group but did not change in the NHD group (difference between the groups 0.37°, p = 0.04). CONCLUSION: This study revealed that longer HD facilitates volume control and improves nutritional status.

Mortality and cardiovascular events in online haemodiafiltration (OL-HDF) compared with high-flux dialysis: results from the Turkish OL-HDF Study.

BACKGROUND: Online haemodiafiltration (OL-HDF) is considered to confer clinical benefits over haemodialysis (HD) in terms of solute removal in patients undergoing maintenance HD. The aim of this study was to compare postdilution OL-HDF and high-flux HD in terms of morbidity and mortality. METHODS: In this prospective, randomized, controlled trial, we enrolled 782 patients undergoing thrice-weekly HD and randomly assigned them in a 1:1 ratio to either postdilution OL-HDF or high-flux HD. The mean age of patients was 56.5 ± 13.9 years, time on HD 57.9 ± 44.6 months with a diabetes incidence of 34.7%. The follow-up period was 2 years, with the mean follow-up of 22.7 ± 10.9 months. The primary outcome was a composite of death from any cause and nonfatal cardiovascular events. The major secondary outcomes were cardiovascular and overall mortality, intradialytic complications, hospitalization rate, changes in several laboratory parameters and medications used. RESULTS: The filtration volume in OL-HDF was 17.2 ± 1.3 L. Primary outcome was not different between the groups (event-free survival of 77.6% in OL-HDF versus 74.8% in the high-flux group, P = 0.28), as well as cardiovascular and overall survival, hospitalization rate and number of hypotensive episodes. In a post hoc analysis, the subgroup of OL-HDF patients treated with a median substitution volume >17.4 L per session (high-efficiency OL-HDF, n = 195) had better cardiovascular (P = 0.002) and overall survival (P = 0.03) compared with the high-flux HD group. In adjusted Cox-regression analysis, treatment with high-efficiency OL-HDF was associated with a 46% risk reduction for overall mortality {RR = 0.54 [95% confidence interval (95% CI) 0.31-0.93], P = 0.02} and a 71% risk reduction for cardiovascular mortality [RR = 0.29 (95% CI 0.12-0.65), P = 0.003] compared with high-flux HD. CONCLUSIONS: The composite of all-cause mortality and nonfatal cardiovascular event rate was not different in the OL-HDF and in the high-flux HD groups. In a post hoc analysis, OL-HDF treatment with substitution volumes over 17.4 L was associated with better cardiovascular and overall survival.

Patient Survival With Extended Home Hemodialysis Compared to In-Center Conventional Hemodialysis.

Introduction: More frequent and/or longer hemodialysis (HD) has been associated with improvements in numerous clinical outcomes in patients on dialysis. Home HD (HHD), which allows more frequent and/or longer dialysis with lower cost and flexibility in treatment planning, is not widely used worldwide. Although, retrospective studies have indicated better survival with HHD, this issue remains controversial. In this multicenter study, we compared thrice-weekly extended HHD with in-center conventional HD (ICHD) in a large patient population with a long-term follow-up. Methods: We matched 349 patients starting HHD between 2010 and 2014 with 1047 concurrent patients on ICHD by using propensity scores. Patients were followed-up with from their respective baseline until September 30, 2018. The primary outcome was overall survival. Secondary outcomes were technique survival; hospitalization; and changes in clinical, laboratory, and medication parameters. Results: The mean duration of dialysis session was 418 ± 54 minutes in HHD and 242 ± 10 minutes in patients on ICHD. All-cause mortality rate was 3.76 and 6.27 per 100 patient-years in the HHD and the ICHD groups, respectively. In the intention-to-treat analysis, HHD was associated with a 40% lower risk for all-cause mortality than ICHD (hazard ratio [HR] = 0.60; 95% confidence interval [CI] 0.45 to 0.80; P < 0.001). In HHD, the 5-year technical survival was 86.5%. HHD treatment provided better phosphate and blood pressure (BP) control, improvements in nutrition and inflammation, and reduction in hospitalization days and medication requirement. Conclusion: These results indicate that extended HHD is associated with higher survival and better outcomes compared to ICHD.

Impact of mean arterial pressure on progression of arterial stiffness in peritoneal dialysis patients under strict volume control strategy.

INTRODUCTION: Arterial stiffness is an important contributor to the increased cardiovascular burden of uremia. The aim of the study was to identify determinants of arterial stiffness progression in peritoneal dialysis (PD) patients with strict volume control. PATIENTS AND METHODS: 89 prevalent PD patients were enrolled. Assessment of arterial stiffness was performed at baseline and after nine months on average (range 8 - 12 months) by carotid-femoral pulse wave velocity (cf-PWV). RESULTS: Mean age was 51 ± 13 y; preceeding time on PD was 40 ± 34 months. 57% of the patients were men and 9% were diabetic. At baseline, mean cf- PWV was 8.7 ± 2.7 m/s and was significantly higher in patients with diabetes and on automated PD therapy. Cf-PWV was positively correlated with age, history of cardiovascular disease, mean arterial pressure (MAP), blood glucose, left atrium diameter and left ventricular mass index. Sixty patients underwent a second cf-PWV measurement. 36% had progression of arterial stiffness. Delta cf- PWV value was 2.08 ± 1.89 m/s for progressors and -1.25 ± 1.43 m/s; p < 0.01 for nonprogressors (p < 0.01). In logistic regression analysis, the change in MAP was the only predictor for progression of arterial stiffness. CONCLUSIONS: MAP is the main determinant of arterial stiffness progression. Our results suggest that efficient blood pressure control may contribute to preserved or reduced arterial stiffness in PD patients.

Relations between malnutrition-inflammation-atherosclerosis and volume status. The usefulness of bioimpedance analysis in peritoneal dialysis patients.

BACKGROUND: Chronic fluid overload (FO) is frequently present in peritoneal dialysis (PD) patients and is associated with hypertension and left ventricular hypertrophy and dysfunction, which are important predictors of death in dialysis patients. In the present study, we investigated the relationship between nutrition, inflammation, atherosclerosis and body fluid volumes measured by multi-frequency bioimpedance analysis (m-BIA) in PD patients. In addition, we analysed the relationship of extracellular volume values by m-BIA to echocardiographic parameters in order to define its usefulness as a measure of FO. METHODS: Ninety-five prevalent PD patients (mean age 50 ± 13 years, 10 of them diabetic) were enrolled. Extracellular water (ECW), total body water (TBW), dry lean mass (DLM) and phase angle (PA) were measured by m-BIA. Volume status was determined by measuring left atrium diameter (LAD) and left ventricular end-diastolic diameter (LVEDD). Measurement of carotid artery intima-media thickness (CA-IMT) was used to assess the presence of subclinical atherosclerosis. Serum albumin was used as a nutritional marker, and serum C-reactive protein (CRP) was used as an inflammatory marker. RESULTS: Mean ECW/height was 10.0 ± 1.0 L/m for whole group and 9.3 ± 0.6 L/m in patients with normal clinical hydration parameters. In correlation analysis, markers of nutrition, inflammation and atherosclerosis correlated well with m-BIA parameters. When we used echographically measured LAD (> 40 mm) or LVEDD (> 55 mm) as a confirmatory parameter, a cut-off value of 10.48 L/m ECW/height (78% specificity, with a sensitivity of 77% for LAD and 72% specificity, with a sensitivity of 70% for LVEDD) was found in ROC analysis for the diagnosis of FO. Patients with FO were older and had higher systolic blood pressure, cardiothoracic index, serum CRP level and mean CA-IMT than patients without FO. Patients with inflammation had higher CA-IMT values. In multivariate analysis, only two factors-low urine output and ECW/height-were independently associated with the presence of inflammation. CONCLUSIONS: FO defined by m-BIA is significantly correlated with markers of malnutrition, inflammation and atherosclerosis in PD patients. The indices obtained from m-BIA, especially ECW/height, correlated well with volume overload as assessed by echocardiography and might be a measure worth testing in a properly designed clinical study.

The influence of dialysate calcium on progression of arterial stiffness in peritoneal dialysis patients.

BACKGROUND: One of the origins of cardiovascular disease in dialysis patients is arterial stiffness. The aim of our study was to assess the relationship between the calcium content of peritoneal dialysis (PD) solution and arterial stiffness. PATIENTS AND METHODS: We enrolled into the study 49 PD patients who had been treated with the same PD solution for the preceding 6 months. The calcium content of the PD solution was 1.25 mmol/L in 34 patients (low-Ca group) and 1.75 mmol/L in 15 patients (high-Ca group). Study patients were followed for 6 months on the same PD prescription. Arterial stiffness was assessed by measurement of augmentation index (AI) and brachial pulse wave velocity (PWV) at baseline and at month 6 (SphygmoCor: Atcor Medical, West Ryde, NSW, Australia). Demographic data were recorded from patient charts. RESULTS: Mean age of the whole group was 51 +/- 11 years, prevalence of diabetes was 14%, duration of PD was 43 +/- 30 months, percentage of women was 45%, and percentage of patients using a cycler was 33%. We observed no differences between groups with regard to those variables or creatinine clearance, residual renal function, Ca, phosphorus, parathormone, C-reactive protein, lipid parameters, and use of phosphate binder with or without Ca content. Mean arterial pressure was higher in the high-Ca group, but the difference was not statistically significant (100 +/- 22 mmHg vs 88 +/- 18 mmHg, p = 0.06). At baseline, AI was significantly higher in the high-Ca group than in the low-Ca group (27% +/- 10% vs 21% +/- 9%, p < 0.05). Measurements of PWV were not different between the groups (8.4 +/- 1.1 m/s vs 8.5 +/- 1.7 m/s). Measurement of arterial stiffness parameters at month 6 revealed that PWV had increased in the high-Ca group (to 9.6 +/- 2.3 m/s from 8.4 +/- 1.1 m/s, p < 0.05), but had not changed in the low-Ca group (to 8.2 +/- 1.9 m/s from 8.5 +/- 1.7 m/s). The AI did not change in either group. CONCLUSIONS: These data suggest that Ca exposure through PD solution plays a role in the progression of arterial stiffness, which may be related to increased vascular calcification.

Effects of thrice weekly nocturnal hemodialysis on arterial stiffness.

OBJECTIVE: In this study, we compared the changes in arterial stiffness in chronic hemodialysis patients treated with 8-h vs. 4-h thrice weekly in-center hemodialysis. METHODS: Sixty prevalent chronic hemodialysis patients assigned to 8-h nocturnal in-center thrice weekly HD (NHD) and 60 control cases assigned to 4-h thrice weekly conventional HD (CHD) were followed for one year. Radial-carotid pulse wave velocity, augmentation index and echocardiography were performed at baseline and 12th month. RESULTS: Mean age of the patients was 49±11 years, 30.8% were female, 27.5% had diabetes mellitus and mean dialysis vintage was 57±47 months. Baseline demographical, clinical and laboratory parameters were similar between groups. During a mean follow-up of 15.0±0.1 months, blood pressure remained similar in both groups while the number of mean daily anti-hypertensive substances decreased in the NHD group. In the NHD group, time-averaged serum phosphorus and calcium-phosphorus product were lower than the CHD group. Pulse wave velocity and augmentation index decreased in the NHD group (from 11.02±2.51 m/s to 9.61±2.39 m/s and from 28.8±10.3% to 26.2±12.1%; p=0.008 and p=0.04, respectively). While augmentation index increased in the CHD group (28.0±9.4 to 31.0±10.7%, p=0.02), pulse wave velocity did not change. Subendocardial viability ratio and ejection duration improved in the NHD group (from 135±28 to 143±25%, p=0.01 and from 294±34 ms to 281±34 ms, p=0.003, respectively), accompanied by regression of left ventricular mass index. In multiple stepwise linear regression analyses, NHD was associated with improvements in augmentation index, ejection duration and subendocardial viability ratio. CONCLUSIONS: These data indicate that arterial stiffness is ameliorated by implementation of longer hemodialysis sessions.