N-Terminal Prohormone of Brain Natriuretic Peptide but not C-Terminal Pre-Pro Vasopressin (Copeptin) Level is Associated with the Response to Antihypertensive Therapy in Haemodialysis Patients.

BACKGROUND/AIMS: Volume overload, frequently clinically asymptomatic is considered as a causative factor limiting the effectiveness of antihypertensive therapy in haemodialysis (HD) patients. Therefore, the aim of this study was to assess plasma levels of N-terminal fragment of the prohormone brain natriuretic peptide (NT-proBNP) and a C-terminal portion of the precursor of vasopressin (CT-proAVP, copeptin), surrogate markers of volume overload in HD patients in relation to the number of antihypertensive drugs used in the hypertension treatment. METHODS: One hundred and fifty adult HD patients (92 males) were enrolled into this study. Clinical data concerning blood pressure (BP) measurements prior haemodialysis session and pharmacotherapy were collected from all patients. In addition to routine laboratory parameters, plasma levels of NT-proBNP and CT-proAVP were measured, and daily sodium and water consumption were estimated with a portion-size food frequency questionnaire. RESULTS: Among 145 (96.7%) hypertensive HD patients, 131 were receiving antihypertensive medication. Despite antihypertensive therapy, 31.0% had inadequate BP control. Plasma concentration of NT-proBNP was associated with systolic (R=0.19; p=0.02) but not diastolic BP values and with the number of received antihypertensive drugs (R=0.21; p=0.01). The highest NT-proBNP values were observed in patients receiving 3 or more antihypertensive drugs. In contrast, no significant correlation was found between plasma CT-proAVP concentrations and BP values as well as and the number of antihypertensive drugs. Receiver operator curve analysis showed that NT-proBNP values over 13,184 pg/mL predicted the use of at least 3 antihypertensive drugs in maximal doses in the therapy of hypertension, similar analyses performed for CT-proAVP showed much less specificity. CONCLUSIONS: 1. Increased levels of NT-proBNP seems to be a better biomarker of multidrug antihypertensive therapy requirement than CT-proAVP. 2. Whether estimation of NT-proBNP in these patients will be also better biomarker than copeptin in the prediction of cardiovascular complications related to hypertension needs further investigations.

Nutrient intake assessed with Diet History Questionnaire II, in relation to long-term calcium-phosphate control in hemodialysis patients with end-stage renal failure.

BACKGROUND: Diet is a key factor that determines proper alignment of calcium-phosphate and nutritional status among hemodialysis (HD) patients. OBJECTIVES: To assess the nutrient intake in relation to long-term calcium-phosphate control in HD patients with end-stage renal failure. MATERIAL AND METHODS: The study included 107 patients (66 men, 41 women) from 10 dialysis centers in the Upper Silesia region of Poland. To analyze the diet composition during the previous year, a portion-sized version of the Diet History Questionnaire II (DHQ-II) from National Institutes of Health was used. The nutrient intake was assessed in accordance with the most complex recommendations on HD patients' nutrition - K/DOQI Clinical Practice Guidelines for nutrition in chronic renal failure. Poor long-term alignment of calcium-phosphate homeostasis was defined as the presence of over 50% monthly phosphorus concentrations exceeding 5 mg/dL, and for calcium 10.2 mg/dL, during the last 6-month period. RESULTS: Lower than recommended protein intake was found in 63% of HD patients (average consumption: 0.9 ±0.5 g/kg/day). Most of the patients consumed too much fat (33.5 ±6.7% of daily energy intake) and sodium (2912 ±1542 mg/day). In 42% of patients, dietary phosphorus intake was consistent with the recommendations (13.3 ±7.5 mg/kg/day). Protein intake over 1.2 g/kg/day resulted in an increased consumption of phosphorous, but did not increase the risk of misalignment of phosphorus concentrations (OR = 1.15 [0.40-3.27]); p = 0.8). Poor control of serum phosphorus concentrations was observed in 69% of patients (they were on average 8 years younger). The average intake of protein and phosphate in the groups with good or not satisfactory serum phosphorus alignment did not differ significantly. CONCLUSIONS: Adequate control of protein intake is not sufficient to obtain phosphorus alignment, especially in younger HD patients.

Relationship between plasma levels of zonulin, bacterial lipopolysaccharides, D-lactate and markers of inflammation in haemodialysis patients.

BACKGROUND: Increased permeability of the intestinal wall and intestinal dysbiosis may contribute to chronic systemic inflammation, one of the causes of accelerated atherosclerosis and cardiovascular morbidity and mortality burden in patients with chronic kidney disease. The aim of this study was to evaluate the association between markers of intestinal permeability and inflammation in haemodialysis (HD) patients. METHODS: Plasma concentration of zonulin, haptoglobin, TNFα, IL6, D-lactates and bacterial lipopolysaccharides (LPS) was assessed in blood samples obtained after overnight fast before midweek morning HD session in 150 stable, prevalent HD patients. Daily intake of energy and macronutrients was assessed on the basis of a food frequency questionnaire. RESULTS: Serum hsCRP level was increased in over 70% of patients. Plasma levels of zonulin [11.6 (10.9-12.3) vs 6.8 (5.8-7.8) ng/mL], IL6 [6.2 (1.0-10.3) vs 1.3 (1.0-2.0) pg/mL] and TNFα [5.9 (2.9-11.8) vs 1.6 (1.3-1.8) pg/mL], but not LPS and D-lactates were significantly higher in HD than in healthy controls. D-lactates and LPS levels were weakly associated with IL6 (R = 0.175; p = 0.03, and R = 0.241; p = 0.003). There was a borderline correlation between plasma zonulin and serum hsCRP (R = 0.159; p = 0.07), but not with IL6, LPS and D-lactates. In multiple regression, both serum CRP and plasma IL6 variability were explained by LPS (ß = 0.143; p = 0.08 and ß = 0.171; p = 0.04, respectively), only. CONCLUSION: The weak association between plasma D-lactate, LPS and IL6 levels indicates that intestinal flora overgrowth or increased intestinal permeability contributes very slightly to the chronic inflammation development in HD patients.

Functional deficiency of vitamin K in hemodialysis patients in Upper Silesia in Poland.

PURPOSE: Functional vitamin K deficiency (both K1 and K2) is postulated to be one of the most relevant links between chronic kidney disease and vascular calcification in hemodialysis (HD) patients. Recommended dietary restrictions in HD patients superimposed on diversity of eating habits across the countries may affect the prevalence of functional vitamin K deficiency. The aim of this study was to determine the level of functional vitamin K deficiency and its relation to vitamin K1 intake in HD patients in Upper Silesia in Poland. METHODS: Protein-induced vitamin K absence or antagonist-II (PIVKA-II) and undercarboxylated matrix Gla protein (ucMGP) were assessed by ELISA in 153 stable, prevalent HD patients and 20 apparently healthy adults (to establish normal ranges for PIVKA-II and ucMGP). Daily phylloquinone intake was assessed using a food frequency questionnaire. RESULTS: PIVKA-II and ucMGP levels were increased in 27.5 and 77.1 % of HD patients in comparison with the reference ranges in apparently healthy controls, respectively. In 45 % of cases, the increased PIVKA-II level was explained by insufficient phylloquinone intake for Polish population (recommended intake: >55 µg for women and >65 µg for men). Applying ROC analysis, we showed that vitamin K1 intake below 40.2 µg/day was associated with increased PIVKA-II levels. There was no correlation between vitamin K1 intake and plasma concentration of ucMGP, or between PIVKA-II and ucMGP. CONCLUSIONS: (1) Functional vitamin K1 deficiency is explained by low vitamin K1 intake in less than half of HD patients. (2) Undercarboxylated matrix Gla protein level is a poor surrogate for functional vitamin K1 deficiency.