Dialysis vintage stratified comparison of body composition, hydration and nutritional state in peritoneal dialysis and hemodialysis patients.

INTRODUCTION: Body mass decomposition and hydration state imbalances affect patients on maintenance dialysis. We compared body composition, hydration and nutritional state of patients on peritoneal dialysis (PD) and hemodialysis (HD) based on dialysis vintage (DV). MATERIAL AND METHODS: Three hundred and fifty-nine prevalent patients on HD (n = 301) and PD (n = 58) were divided into 3 subgroups depending on DV: < 2 years HD (n = 41) and PD (n = 28), 2-4 years HD (n = 111) and PD (n = 17), > 4 years HD (n = 149) and PD (n = 13). Bioimpedance analysis delivered data including overhydration (OH), Lean (LTM) and adipose lipids mass (FAT). Other measurements included daily diuresis (DD), subjective global assessment (SGA) and serum albumin (alb), C-reactive protein (CRP) and total cholesterol (TChol), and hemoglobin (Hb). RESULTS: Dialysis vintage < 2 years. Hemodialysis patients were older (65.5 ±18.5 vs. 50.9 ±17.1; p < 0.01) with a higher mortality (28 vs. 1; p < 0.01) and OH (8.0 ±4.3 vs. 1.6 ±3.1; p < 0.001). Hemoglobin (10.6 ±1.5 vs. 11.8 ±1.7; p < 0.05), TChol (180.2 ±47.0 vs. 211.7 ±46.3; p < 0.05), DD (871 ±729 vs. 1695 ±960; p < 0.001) and LTM (46.5 ±12.9 vs. 53.8 ±14.4; p < 0.05) were lower on HD. Dialysis vintage 2-4 years: when compared to PD, HD patients had higher OH (11.7 ±5.9 vs. 2.1 ±3.2; p < 0.001) and lower Hb (10.8 ±1.5 vs. 11.9 ±1.4; p < 0.01). Dialysis vintage > 4 years: compared to PD, HD patients had higher LTM (44.3 ±11.7 vs. 38.6 ±7.9; p < 0.05) and lower FAT (34.4 ±11.1 vs. 42.8 ±6.4; p < 0.01). CONCLUSIONS: Dialysis patients' body composition depends on dialysis modality and DV. Dialysis vintage < 2 years is associated with better hydration, nutritional state, and survival in PD patients, but longer DV reduces these benefits. Dialysis vintage > 4 years associated with similar hydration and mortality in both PD and HD while body composition was better on HD.

Dialysis vintage and cardiovascular injury as factors influencing long-term survival in peritoneal dialysis and hemodialysis.

BACKGROUND: Cardiovascular (CV) incidents are the major cause of mortality in maintenance dialysis (MD) patients undergoing peritoneal dialysis (PD) or hemodialysis (HD). CV injury indicators may be useful to investigate the dialysis modality influence on survival. OBJECTIVES: The aim of this study was to compare selected laboratory and echocardiographic (ECHO) markers of CV injury in terms of dialysis vintage (DV), CV-related mortality and all-cause mortality. MATERIAL AND METHODS: The study involved 301 patients on HD (n = 301) and PD (n = 58), who were divided into subgroups according to DV. The subjects' medical histories included diabetes mellitus (DM), myocardial infarction (MI), stroke, CV deaths and deaths from non-CV causes. Their CV parameters were measured with ECHO for the left ventricle ejection fraction (EF), posterior wall (LVW) and interventricular septum (IVS). Serum analyses of cardiac troponin T (TnT) and N-terminal pro-brain natriuretic peptide (BNP) were also carried out. RESULTS: In the subgroup with a DV of 4 years, the PD and HD patients were of a similar age, and had similar mortality and morbidity rates and CV markers, except for thicker IVS in the HD patients. CONCLUSIONS: Focusing on the data analysis based on mortality, and both laboratory and echocardiographic markers of cardiovascular injury, PD seems to be a more favorable method of dialysis. The advantage of PD was noted in subjects with a DV < 2 years. HD showed no outcome benefit over PD in longer DV.

N­terminal pro­B-type natriuretic peptide as a marker of hypervolemia and predictor of increased mortality in patients on hemodialysis.

INTRODUCTION: N­terminal pro­B­type natriuretic peptide (NT­proBNP) is an established biomarker of heart failure in the general population. However, its diagnostic value is unclear in hemodialysis (HD) patients owing to renal insufficiency. OBJECTIVES: The aim of the study was to establish the usefulness of NT­proBNP for hydration assessment and the relation of NT­proBNP to the nutritional state and prognosis of survival. PATIENTS AND METHODS: In 321 HD patients (206 men; mean age, 65.1 ±21.4 years), we assessed NT­proBNP levels, overhydration (OHBIA), and the indices of the nutritional state (using a bioimpedance analysis [BIA]) in relation to cardiac troponin T (cTnT), hemoglobin, albumin, total cholesterol (TC), and C­reactive protein (CRP) levels. The efficacy of HD was assessed using Kt/V, weekly HD dose, and HD session ultrafiltration. The cohort was divided into NT­proBNP quartiles. Patients with 2 NT­proBNP measurements were categorized also into change­over­time subgroups. A follow­up lasted for a median period of 23.8 ±26.3 months. RESULTS: Relative OHBIA increased across the NT­proBNP quartiles (Q1/Q2/Q3/Q4, 1.31% ±2.56%/2.06% ±2.35%/2.92% ±2.97%/4.62% ±4.22%; P <0.0001). NT­proBNP was also closely associated with other OH parameters. In addition, there was a significant correlation between NT­proBNP and cTnT (r = 0.55; P <0.0001). Body mass index (BMI) and fat tissue index (FTI) decreased across the quartiles (BMI, 28.5 ±7.7/26.0 ±6.6/25.8 ±5.4/23.7 ±5.5 kg/m2; FTI, 14.4 ±9.0/14.1 ±7.3/12.3 ±6.8/11.6 ±6.1; P <0.001). The highest albumin level was present in Q1 (4.10 ±0.63/3.99 ±0.51/3.90 ±0.62/3.97 ±0.78 g/dl; P = 0.006). The TC level was the lowest in Q4 (190 ±60/169 ±56/173 ±51/153 ±56 mg/dl; P = 0.002). The hemoglobin level decreased across the quartiles (11.44 ±1.25/11.15 ±2.50/10.79 ±1.51/10.45 ±1.67 g/dl; P = 0.0006). The differences in CRP levels and HD­related parameters were nonsignificant. During the follow­up, 97 deaths were recorded (11/26/21/39, P <0.0001). CONCLUSIONS: NT­proBNP seems to be a useful biomarker of hypervolemia in HD patients. Nevertheless, it has to be interpreted with regard to the patient's individual residual renal function and cardiovascular status.

Cardiac Troponin T and Hydration Status as Prognostic Markers in Hemodialysis Patients.

This study aimed to assess cardiac troponin T (cTnT) and hydration state as cardiovascular (CV) risk markers in hemodialysis (HD) patients. Two hundred and forty one patients were divided according to HD vintage into two groups: SV (HD ≤24 months) and LV. Water balance was assessed with overhydration (OH%; bioimpedance analysis) and daily diuresis (DD); CV dysfunction with cTnT and heart ultrasound; nutrition with subjective global assessment (SGA), cholesterol (TC) and albumin. SV had lower OH% (2.8 vs. 3.5, p < 0.05) and higher DD (1,161 vs. 637 ml, p < 0.001), while LV had higher cTnT (0.1 ± 0.04 vs. 0.1 ± 0.07 ng/ml, p < 0.05) and lower interventricular septum thickness (IVS; 13.4 vs. 14.5 mm, p < 0.05). Nutritional state as reflected by lower TC was worse in LV (184.7 vs. 169.5 mg/dl, p < 0.05). Mortality was higher in patients in the LV group (15 vs. 27 deaths, p < 0.05). OH% correlated inversely with albumin (r = -0.36, p < 0.001), TC (r = -0.31, p < 0.001) and cTnT (r = -0.4, p < 0.001). cTnT correlated positively with IVS (r = 0.39, p < 0.001), SGA (r = 0.23, p = 0.001) and mortality rate (r = 0.21, p < 0.01), and negatively with DD (r = -0.34, p < 0.001) and albumin (r = -0.25, p < 0.001). Longer dialysis vintage associates with CV dysfunction, overhydration and increased mortality, which may be predicted with OH% and cTnT. Video Journal Club 'Cappuccino with Claudio Ronco' at http://www.karger.com/?doi=376603.