The Impact of Selected Factors on the Cardiovascular System in Chronic Kidney Disease
NCT ID: NCT05214872
Last Updated: 2022-01-31
Study Results
The study team has not published outcome measurements, participant flow, or safety data for this trial yet. Check back later for updates.
Basic Information
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COMPLETED
252 participants
OBSERVATIONAL
2016-03-25
2020-09-30
Brief Summary
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Detailed Description
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The main goal of this study was to analyze the mechanisms leading to the increased tendency to cardiovascular disturbances in CKD, with particular focus on the parameters of oxidative stress, inflammation and the results of imaging examinations (intima-media thickness (IMT) assessments) and other non-invasive cardiological examinations based on the results using the Portapres device (Finapres Medical Systems (FMS), the Netherlands), the SphygmoCor tonometer (AtCor Medical), the Colin blood pressure monitor (BMP)-7000 (Japan) Pulse Trace 2000 (Micro Medical Ltd., Rochester, Kent, United Kingdom) The Accuson CV 70 system (Siemens) with a 10 megahertz (Mhz) transducer.
Besides, studied participants were followed 2 years after enrollment to study for recording cardiovascular-related death.
Conditions
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Keywords
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Study Design
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CASE_CONTROL
CROSS_SECTIONAL
Study Groups
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PREDIALYSIS GROUP
(n = 48) - patients in the pre-dialysis period (stages G3b-G4 of chronic kidey disease (CKD)) with moderate or severe decrease in estimated glomerular filtration rate (eGFR) (eGFR 44-29 ml/min/1.73 m\^2)
laboratory parameters - complete blood count
the complete blood count was analyzed using Sysmex K-4500 Automated Hematology Analyzer (by GMI Inc., USA):
* hemoglobin (HGB) \[g/dl\];
* red blood count (RBC) \[10\^12/l\];
* hematocrit (HCT) \[l/l\];
* white blood cells (WBC) \[10\^9/l\];
* platelet count (PLT) \[10\^9/l\]
body mass index (BMI) [kg/m^2] calculation
body mass index (BMI) \[kg/m\^2\] was calculated by dividing a person's weight (post-HD weight in HD group) \[kg\] by the squared their body height \[m\]
selected parameters of oxidative stress (1)
Serum concentration of:
* advanced glycation ends products (AGE) \[µg/mg protein\];
* 3-nitrotyrosine (3-NT) \[µmol/mg protein\];
* advanced oxidation protein products (AOPP) \[µmol/mg protein\];
* carboxymethyle(lysine) (CML) \[µg/mg protein\]
were determined with the enzyme immunoassay methods (ELISA) using Shanghai Sunred Biological Technology Co kits, China.
metalloproteinases
metalloproteinases in the serum \[ng/ml\]:
* metalloproteinase 9 (MMP-9) in the serum was determined by the ELISA method using the Quantikine Human MMP-9 (total) kit, by R\&D Systems, Canada;
* tissue inhibitor of metalloproteinase 1 (TIMP-1) in the serum - was determined by the ELISA method using the Quantikine Human TIMP-1 kit, manufactured by R\&D Systems, Canada;
* the MMP-9/TIMP-1 ratio was calculated by the quotient of the MMP-9 and the TIMP-1 concentration.
parameters of lipids metabolism in the serum
* total cholesterol (T-C) \[mg/dl\] - was assessed by routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA;
* low-density lipoprotein cholesterol (LDL-C) \[mg/dl\] - was assessed by routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA;
* high-density lipoprotein cholesterol (HDL-C) \[mg/dl\] - was assessed by routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA;
* triglycerides (TG) \[mg/dl\] - were assessed by routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA;
* the concentration of low-density lipoprotein (LDL-C) cholesterol - was determined from Friedewalds' equation (LDL-C \[mg/dl\] = total cholesterol (T-C) \[mg/dl\]- HDL-C \[mg/dl\]- TG\[mg/dl\]/5).
parameters of iron metabolism
* iron concentration \[mg/dl\] - was analyzed with the Cobas Integra 400 plus biochemical analyzer from Roche Diagnostics, USA;
* total iron-binding capacity (TIBC) \[mg/dl\] - was analyzed with the Cobas Integra 400 plus biochemical analyzer from Roche Diagnostics, USA;
* the unsaturated iron-binding capacity (UIBC) \[mg/dl\] was determined by an equation in which iron concentration in plasma is subtracted from TIBC \[mg/dl\];
* ferritin \[ng/ml\] concentration was determined with the Modular E-170 biochemical analyzer from Roche Diagnostics, USA.
selected inflammatory markers
* high-sensitivity C-reactive protein (hsCRP) \[mg/l\] was measured using DADE Behring, USA and the DADE nephelometer Behring Analyzer II;
* neopterin \[nmol/l\] was determined by using the Neopterin ELISA kit, DRG International, Inc., USA;
* interleukin 18 (IL-18) \[pg/ml\] concentration was determined by Colorimetric Sandwich ELISA, Quantikine Human IL-18 R\&D Inc., USA.
carotid intima-media thickness (IMT)
carotid intima-media thickness (IMT) \[mm\] was measured by The Accuson CV 70 system (Siemens) with a 10 megahertz (Mhz) transducer.
Two longitudinal projections were assessed (anterolateral and posterolateral). The distal 1 cm of the common carotid artery just proximal to the bulb was measured by means of a computer analysis system (Medical Imaging Applications, LLC).
non-invasive cardiological examinations
For non-invasive cardiological examinations, the Portapres device (Finapres Medical Systems (FMS), the Netherlands), the SphygmoCor tonometer (AtCor Medical), the Colin blood pressure monitor (BMP)-7000 (Japan) were used.
Main assessed variables: heart rate (HR) \[beats per minute \[bpm\]\]; ejection duration (ED) \[millisecons\]; peripheral systolic (pSBP) and diastolic blood pressure (pDBP) \[mm Hg\]; peripheral mean arterial pressure (pMAP) \[mm Hg\]; peripheral end-systolic pressure (pESP) \[mm Hg\]; central systolic (cSBP) and diastolic blood pressure (cDBP) \[mm Hg\]; central mean arterial pressure (cMAP) \[mm Hg\]; central augmented pressure (cAP) \[mmHg\]; central mean pressure of diastole (cMPD)\[mm Hg\]; central mean pressure of systole (cMPS) \[mm Hg\]; central end-systolic pressure (cESP) \[mm Hg\].
vessel stiffness assessment
The following parameters of vessel stiffness were assessed by Pulse Trace 2000 (Micro Medical Ltd., Rochester, Kent, United Kingdom):
* reflection index (RI) \[in percentages \[%\]\];
* vascular stiffness index (SI) \[m/s\];
* peripheral pulse pressure (pPP) \[mm Hg\];
* central puls pressure (cPP) \[mm Hg\]
* peripheral pulse pressure/central pulse pressure (pPP/cPP ratio).
cardiovascular (CV)-related death recording during 2-year follow-up
During a 2-year follow-up from the enrollment to this study, CV-related fatal incidents history has been recorded for each subject separately. The primary endpoint was fatal acute myocardial infarction (AMI) or acute ischemic stroke or any unexpected or sudden death only if autopsy proved CV-related. If there was doubt about the cause of death or there was no contact with the patient during the two years from study enrollment, that patient was excluded and not considered further.
glucose (Glu)
glucose (Glu) \[mg/dl\] was assessed in the serum by a routine technique using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA.
klotho
klotho \[ng/ml\] - was analyzed in the serum by Human KL(Klotho) \[ng/ml\] ELISA Kit, Shanghai Sunred Biological Technology Co kit, China.
fibroblast growth factor 23 (FGF-23)
FGF-23 \[pg/ml\] - was analyzed in rhe serum using Human FGF-23 ELISA Kit, Sigma-Aldrich, USA.
parameters of calcium and phosphate metabolism
* total and ionized calcium \[mg/dl\],
* phosphate \[mg/dl\],
* intact parathormone (iPTH) \[mg/dl\]
were assessed by routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA.
liver enzymes activity assessment
activity of:
* alanine transaminase (ALT) \[U/l\];
* aspartate transaminase (AST) \[U/l\];
* alkaline phosphatase (ALP) \[U/l\]
were assessed by routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA.
total protein and albumin
* total protein (TP) \[g/dl\];
* albumin (ALB) \[g/dl\]
were assessed in the serum by routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA.
creatinine and urea
* creatinine in the serum \[mg/dl\] - the assay is based on the reaction of creatinine with sodium picrate as described by Jaffe (Jaffes' colorimetric method) - was assessed by routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA;
* urea \[mg/dl\] in the serum - was assessed by routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA.
selected parameters of oxidative stress (2)
myeloperoxidase (MPO) \[ng/ml\] in the serum- was determined by the ELISA method using the Quantikine Human MPO test by R\&D Systems kit, Canada.
selected parameters of oxidative stress (3) sRAGE
soluble receptor for advanced glycation end products (sRAGE) \[µg/mg protein\] in the serum was tested with enzymatic immunoassay (Quantikine ELISA) using R\&D Systems kit, Canada.
selected parameters of oxidative stress (4) MG, CEL, carbamyl protein groups
* methylglyoxal (MG) \[µg/mg protein\];
* carboxyethyle(lysine) (CEL) \[µg/mg protein\];
* carbamyl protein groups \[µg/mg protein\] were assessed in the serum by competitive enzyme immunoassay (competitive ELISA) using kits from Cell Biolabs Inc, USA.
selected electrolytes assessment
* potassium (K) \[mmol/l\];
* sodium (Na) \[mmol/l\];
* magnesium (Mg) \[mg/dL\]
were assessed in the serum by routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA.
NT-pro-brain natriuretic peptide (NT-proBNP)
NT-proBNP \[fmol/ml\] - was analyzed in the serum by enzyme immunoassay using the Nt-proBNP kit from Biomedica, Slovakia.
estimated glomerular filtration rate (eGFR) calculation
eGFR \[ml/min/1.73m\^2\] - according to the Kidney Disease: Improving Global Outcomes (KDIGO) 2012 recommendations was calculated based on the Modification of Diet in Renal Disease (MDRD) formula: eGFR = 186 x \[creatinine concentration in mg/dl\] - 1.154 x \[age in years\] - 0.203 x \[0.724\] for the female gender.
END-STAGE RENAL DISEASE (ESRD) GROUP
Patients with ESRD (n=106) - (eGFR \<15 ml/min /1.73 m\^2) undergoing renal replacement therapy have formed this group.
Depending on the method of renal replacement therapy used, two subgroups have been distinguished: (1) peritoneal dialysis (PD) subgroup (n=35) including patients treated by peritoneal dialysis. In this subgroup, due to the treatment technique, two groups have been distinguished, a group (n=15) treated with the automatic peritoneal dialysis (APD) technique and a group (n = 20) using the technique of continuous cycling peritoneal dialysis (CCPD), (2) hemodialysis (HD) subgroup (n = 71) including patients treated with repeated hemodialysis. The duration of hemodialysis was at least 10 hours/week using standard bicarbonate dialysis fluids and polysulfone low-flux dialyzers. The blood flow during hemodialysis was 200-350 ml/min, with an average dialysis fluid flow of 500 ml/min.
laboratory parameters - complete blood count
the complete blood count was analyzed using Sysmex K-4500 Automated Hematology Analyzer (by GMI Inc., USA):
* hemoglobin (HGB) \[g/dl\];
* red blood count (RBC) \[10\^12/l\];
* hematocrit (HCT) \[l/l\];
* white blood cells (WBC) \[10\^9/l\];
* platelet count (PLT) \[10\^9/l\]
body mass index (BMI) [kg/m^2] calculation
body mass index (BMI) \[kg/m\^2\] was calculated by dividing a person's weight (post-HD weight in HD group) \[kg\] by the squared their body height \[m\]
selected parameters of oxidative stress (1)
Serum concentration of:
* advanced glycation ends products (AGE) \[µg/mg protein\];
* 3-nitrotyrosine (3-NT) \[µmol/mg protein\];
* advanced oxidation protein products (AOPP) \[µmol/mg protein\];
* carboxymethyle(lysine) (CML) \[µg/mg protein\]
were determined with the enzyme immunoassay methods (ELISA) using Shanghai Sunred Biological Technology Co kits, China.
metalloproteinases
metalloproteinases in the serum \[ng/ml\]:
* metalloproteinase 9 (MMP-9) in the serum was determined by the ELISA method using the Quantikine Human MMP-9 (total) kit, by R\&D Systems, Canada;
* tissue inhibitor of metalloproteinase 1 (TIMP-1) in the serum - was determined by the ELISA method using the Quantikine Human TIMP-1 kit, manufactured by R\&D Systems, Canada;
* the MMP-9/TIMP-1 ratio was calculated by the quotient of the MMP-9 and the TIMP-1 concentration.
parameters of lipids metabolism in the serum
* total cholesterol (T-C) \[mg/dl\] - was assessed by routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA;
* low-density lipoprotein cholesterol (LDL-C) \[mg/dl\] - was assessed by routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA;
* high-density lipoprotein cholesterol (HDL-C) \[mg/dl\] - was assessed by routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA;
* triglycerides (TG) \[mg/dl\] - were assessed by routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA;
* the concentration of low-density lipoprotein (LDL-C) cholesterol - was determined from Friedewalds' equation (LDL-C \[mg/dl\] = total cholesterol (T-C) \[mg/dl\]- HDL-C \[mg/dl\]- TG\[mg/dl\]/5).
parameters of iron metabolism
* iron concentration \[mg/dl\] - was analyzed with the Cobas Integra 400 plus biochemical analyzer from Roche Diagnostics, USA;
* total iron-binding capacity (TIBC) \[mg/dl\] - was analyzed with the Cobas Integra 400 plus biochemical analyzer from Roche Diagnostics, USA;
* the unsaturated iron-binding capacity (UIBC) \[mg/dl\] was determined by an equation in which iron concentration in plasma is subtracted from TIBC \[mg/dl\];
* ferritin \[ng/ml\] concentration was determined with the Modular E-170 biochemical analyzer from Roche Diagnostics, USA.
selected inflammatory markers
* high-sensitivity C-reactive protein (hsCRP) \[mg/l\] was measured using DADE Behring, USA and the DADE nephelometer Behring Analyzer II;
* neopterin \[nmol/l\] was determined by using the Neopterin ELISA kit, DRG International, Inc., USA;
* interleukin 18 (IL-18) \[pg/ml\] concentration was determined by Colorimetric Sandwich ELISA, Quantikine Human IL-18 R\&D Inc., USA.
carotid intima-media thickness (IMT)
carotid intima-media thickness (IMT) \[mm\] was measured by The Accuson CV 70 system (Siemens) with a 10 megahertz (Mhz) transducer.
Two longitudinal projections were assessed (anterolateral and posterolateral). The distal 1 cm of the common carotid artery just proximal to the bulb was measured by means of a computer analysis system (Medical Imaging Applications, LLC).
non-invasive cardiological examinations
For non-invasive cardiological examinations, the Portapres device (Finapres Medical Systems (FMS), the Netherlands), the SphygmoCor tonometer (AtCor Medical), the Colin blood pressure monitor (BMP)-7000 (Japan) were used.
Main assessed variables: heart rate (HR) \[beats per minute \[bpm\]\]; ejection duration (ED) \[millisecons\]; peripheral systolic (pSBP) and diastolic blood pressure (pDBP) \[mm Hg\]; peripheral mean arterial pressure (pMAP) \[mm Hg\]; peripheral end-systolic pressure (pESP) \[mm Hg\]; central systolic (cSBP) and diastolic blood pressure (cDBP) \[mm Hg\]; central mean arterial pressure (cMAP) \[mm Hg\]; central augmented pressure (cAP) \[mmHg\]; central mean pressure of diastole (cMPD)\[mm Hg\]; central mean pressure of systole (cMPS) \[mm Hg\]; central end-systolic pressure (cESP) \[mm Hg\].
vessel stiffness assessment
The following parameters of vessel stiffness were assessed by Pulse Trace 2000 (Micro Medical Ltd., Rochester, Kent, United Kingdom):
* reflection index (RI) \[in percentages \[%\]\];
* vascular stiffness index (SI) \[m/s\];
* peripheral pulse pressure (pPP) \[mm Hg\];
* central puls pressure (cPP) \[mm Hg\]
* peripheral pulse pressure/central pulse pressure (pPP/cPP ratio).
cardiovascular (CV)-related death recording during 2-year follow-up
During a 2-year follow-up from the enrollment to this study, CV-related fatal incidents history has been recorded for each subject separately. The primary endpoint was fatal acute myocardial infarction (AMI) or acute ischemic stroke or any unexpected or sudden death only if autopsy proved CV-related. If there was doubt about the cause of death or there was no contact with the patient during the two years from study enrollment, that patient was excluded and not considered further.
glucose (Glu)
glucose (Glu) \[mg/dl\] was assessed in the serum by a routine technique using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA.
klotho
klotho \[ng/ml\] - was analyzed in the serum by Human KL(Klotho) \[ng/ml\] ELISA Kit, Shanghai Sunred Biological Technology Co kit, China.
fibroblast growth factor 23 (FGF-23)
FGF-23 \[pg/ml\] - was analyzed in rhe serum using Human FGF-23 ELISA Kit, Sigma-Aldrich, USA.
parameters of calcium and phosphate metabolism
* total and ionized calcium \[mg/dl\],
* phosphate \[mg/dl\],
* intact parathormone (iPTH) \[mg/dl\]
were assessed by routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA.
liver enzymes activity assessment
activity of:
* alanine transaminase (ALT) \[U/l\];
* aspartate transaminase (AST) \[U/l\];
* alkaline phosphatase (ALP) \[U/l\]
were assessed by routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA.
total protein and albumin
* total protein (TP) \[g/dl\];
* albumin (ALB) \[g/dl\]
were assessed in the serum by routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA.
creatinine and urea
* creatinine in the serum \[mg/dl\] - the assay is based on the reaction of creatinine with sodium picrate as described by Jaffe (Jaffes' colorimetric method) - was assessed by routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA;
* urea \[mg/dl\] in the serum - was assessed by routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA.
selected parameters of oxidative stress (2)
myeloperoxidase (MPO) \[ng/ml\] in the serum- was determined by the ELISA method using the Quantikine Human MPO test by R\&D Systems kit, Canada.
selected parameters of oxidative stress (3) sRAGE
soluble receptor for advanced glycation end products (sRAGE) \[µg/mg protein\] in the serum was tested with enzymatic immunoassay (Quantikine ELISA) using R\&D Systems kit, Canada.
selected parameters of oxidative stress (4) MG, CEL, carbamyl protein groups
* methylglyoxal (MG) \[µg/mg protein\];
* carboxyethyle(lysine) (CEL) \[µg/mg protein\];
* carbamyl protein groups \[µg/mg protein\] were assessed in the serum by competitive enzyme immunoassay (competitive ELISA) using kits from Cell Biolabs Inc, USA.
selected electrolytes assessment
* potassium (K) \[mmol/l\];
* sodium (Na) \[mmol/l\];
* magnesium (Mg) \[mg/dL\]
were assessed in the serum by routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA.
NT-pro-brain natriuretic peptide (NT-proBNP)
NT-proBNP \[fmol/ml\] - was analyzed in the serum by enzyme immunoassay using the Nt-proBNP kit from Biomedica, Slovakia.
estimated glomerular filtration rate (eGFR) calculation
eGFR \[ml/min/1.73m\^2\] - according to the Kidney Disease: Improving Global Outcomes (KDIGO) 2012 recommendations was calculated based on the Modification of Diet in Renal Disease (MDRD) formula: eGFR = 186 x \[creatinine concentration in mg/dl\] - 1.154 x \[age in years\] - 0.203 x \[0.724\] for the female gender.
CARDIOLOGY (CARD) GROUP
CARD group (n = 37) - patients with at least one history of a cardiovascular event, admitted to hospital for elective angiography, without any signs of impaired kidney function.
The studies in this group were conducted to check the changes that occur as a result of cardiovascular disease (CVD) but without kidney disease.
laboratory parameters - complete blood count
the complete blood count was analyzed using Sysmex K-4500 Automated Hematology Analyzer (by GMI Inc., USA):
* hemoglobin (HGB) \[g/dl\];
* red blood count (RBC) \[10\^12/l\];
* hematocrit (HCT) \[l/l\];
* white blood cells (WBC) \[10\^9/l\];
* platelet count (PLT) \[10\^9/l\]
body mass index (BMI) [kg/m^2] calculation
body mass index (BMI) \[kg/m\^2\] was calculated by dividing a person's weight (post-HD weight in HD group) \[kg\] by the squared their body height \[m\]
selected parameters of oxidative stress (1)
Serum concentration of:
* advanced glycation ends products (AGE) \[µg/mg protein\];
* 3-nitrotyrosine (3-NT) \[µmol/mg protein\];
* advanced oxidation protein products (AOPP) \[µmol/mg protein\];
* carboxymethyle(lysine) (CML) \[µg/mg protein\]
were determined with the enzyme immunoassay methods (ELISA) using Shanghai Sunred Biological Technology Co kits, China.
metalloproteinases
metalloproteinases in the serum \[ng/ml\]:
* metalloproteinase 9 (MMP-9) in the serum was determined by the ELISA method using the Quantikine Human MMP-9 (total) kit, by R\&D Systems, Canada;
* tissue inhibitor of metalloproteinase 1 (TIMP-1) in the serum - was determined by the ELISA method using the Quantikine Human TIMP-1 kit, manufactured by R\&D Systems, Canada;
* the MMP-9/TIMP-1 ratio was calculated by the quotient of the MMP-9 and the TIMP-1 concentration.
parameters of lipids metabolism in the serum
* total cholesterol (T-C) \[mg/dl\] - was assessed by routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA;
* low-density lipoprotein cholesterol (LDL-C) \[mg/dl\] - was assessed by routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA;
* high-density lipoprotein cholesterol (HDL-C) \[mg/dl\] - was assessed by routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA;
* triglycerides (TG) \[mg/dl\] - were assessed by routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA;
* the concentration of low-density lipoprotein (LDL-C) cholesterol - was determined from Friedewalds' equation (LDL-C \[mg/dl\] = total cholesterol (T-C) \[mg/dl\]- HDL-C \[mg/dl\]- TG\[mg/dl\]/5).
parameters of iron metabolism
* iron concentration \[mg/dl\] - was analyzed with the Cobas Integra 400 plus biochemical analyzer from Roche Diagnostics, USA;
* total iron-binding capacity (TIBC) \[mg/dl\] - was analyzed with the Cobas Integra 400 plus biochemical analyzer from Roche Diagnostics, USA;
* the unsaturated iron-binding capacity (UIBC) \[mg/dl\] was determined by an equation in which iron concentration in plasma is subtracted from TIBC \[mg/dl\];
* ferritin \[ng/ml\] concentration was determined with the Modular E-170 biochemical analyzer from Roche Diagnostics, USA.
selected inflammatory markers
* high-sensitivity C-reactive protein (hsCRP) \[mg/l\] was measured using DADE Behring, USA and the DADE nephelometer Behring Analyzer II;
* neopterin \[nmol/l\] was determined by using the Neopterin ELISA kit, DRG International, Inc., USA;
* interleukin 18 (IL-18) \[pg/ml\] concentration was determined by Colorimetric Sandwich ELISA, Quantikine Human IL-18 R\&D Inc., USA.
carotid intima-media thickness (IMT)
carotid intima-media thickness (IMT) \[mm\] was measured by The Accuson CV 70 system (Siemens) with a 10 megahertz (Mhz) transducer.
Two longitudinal projections were assessed (anterolateral and posterolateral). The distal 1 cm of the common carotid artery just proximal to the bulb was measured by means of a computer analysis system (Medical Imaging Applications, LLC).
non-invasive cardiological examinations
For non-invasive cardiological examinations, the Portapres device (Finapres Medical Systems (FMS), the Netherlands), the SphygmoCor tonometer (AtCor Medical), the Colin blood pressure monitor (BMP)-7000 (Japan) were used.
Main assessed variables: heart rate (HR) \[beats per minute \[bpm\]\]; ejection duration (ED) \[millisecons\]; peripheral systolic (pSBP) and diastolic blood pressure (pDBP) \[mm Hg\]; peripheral mean arterial pressure (pMAP) \[mm Hg\]; peripheral end-systolic pressure (pESP) \[mm Hg\]; central systolic (cSBP) and diastolic blood pressure (cDBP) \[mm Hg\]; central mean arterial pressure (cMAP) \[mm Hg\]; central augmented pressure (cAP) \[mmHg\]; central mean pressure of diastole (cMPD)\[mm Hg\]; central mean pressure of systole (cMPS) \[mm Hg\]; central end-systolic pressure (cESP) \[mm Hg\].
vessel stiffness assessment
The following parameters of vessel stiffness were assessed by Pulse Trace 2000 (Micro Medical Ltd., Rochester, Kent, United Kingdom):
* reflection index (RI) \[in percentages \[%\]\];
* vascular stiffness index (SI) \[m/s\];
* peripheral pulse pressure (pPP) \[mm Hg\];
* central puls pressure (cPP) \[mm Hg\]
* peripheral pulse pressure/central pulse pressure (pPP/cPP ratio).
cardiovascular (CV)-related death recording during 2-year follow-up
During a 2-year follow-up from the enrollment to this study, CV-related fatal incidents history has been recorded for each subject separately. The primary endpoint was fatal acute myocardial infarction (AMI) or acute ischemic stroke or any unexpected or sudden death only if autopsy proved CV-related. If there was doubt about the cause of death or there was no contact with the patient during the two years from study enrollment, that patient was excluded and not considered further.
glucose (Glu)
glucose (Glu) \[mg/dl\] was assessed in the serum by a routine technique using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA.
klotho
klotho \[ng/ml\] - was analyzed in the serum by Human KL(Klotho) \[ng/ml\] ELISA Kit, Shanghai Sunred Biological Technology Co kit, China.
fibroblast growth factor 23 (FGF-23)
FGF-23 \[pg/ml\] - was analyzed in rhe serum using Human FGF-23 ELISA Kit, Sigma-Aldrich, USA.
parameters of calcium and phosphate metabolism
* total and ionized calcium \[mg/dl\],
* phosphate \[mg/dl\],
* intact parathormone (iPTH) \[mg/dl\]
were assessed by routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA.
liver enzymes activity assessment
activity of:
* alanine transaminase (ALT) \[U/l\];
* aspartate transaminase (AST) \[U/l\];
* alkaline phosphatase (ALP) \[U/l\]
were assessed by routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA.
total protein and albumin
* total protein (TP) \[g/dl\];
* albumin (ALB) \[g/dl\]
were assessed in the serum by routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA.
creatinine and urea
* creatinine in the serum \[mg/dl\] - the assay is based on the reaction of creatinine with sodium picrate as described by Jaffe (Jaffes' colorimetric method) - was assessed by routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA;
* urea \[mg/dl\] in the serum - was assessed by routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA.
selected parameters of oxidative stress (2)
myeloperoxidase (MPO) \[ng/ml\] in the serum- was determined by the ELISA method using the Quantikine Human MPO test by R\&D Systems kit, Canada.
selected parameters of oxidative stress (3) sRAGE
soluble receptor for advanced glycation end products (sRAGE) \[µg/mg protein\] in the serum was tested with enzymatic immunoassay (Quantikine ELISA) using R\&D Systems kit, Canada.
selected parameters of oxidative stress (4) MG, CEL, carbamyl protein groups
* methylglyoxal (MG) \[µg/mg protein\];
* carboxyethyle(lysine) (CEL) \[µg/mg protein\];
* carbamyl protein groups \[µg/mg protein\] were assessed in the serum by competitive enzyme immunoassay (competitive ELISA) using kits from Cell Biolabs Inc, USA.
selected electrolytes assessment
* potassium (K) \[mmol/l\];
* sodium (Na) \[mmol/l\];
* magnesium (Mg) \[mg/dL\]
were assessed in the serum by routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA.
NT-pro-brain natriuretic peptide (NT-proBNP)
NT-proBNP \[fmol/ml\] - was analyzed in the serum by enzyme immunoassay using the Nt-proBNP kit from Biomedica, Slovakia.
estimated glomerular filtration rate (eGFR) calculation
eGFR \[ml/min/1.73m\^2\] - according to the Kidney Disease: Improving Global Outcomes (KDIGO) 2012 recommendations was calculated based on the Modification of Diet in Renal Disease (MDRD) formula: eGFR = 186 x \[creatinine concentration in mg/dl\] - 1.154 x \[age in years\] - 0.203 x \[0.724\] for the female gender.
Chronic kidney disease (CKD) 1-2 GROUP
CKD1-2 (n=29) (stage G1-G2 CKD) with mild decrease in eGFR (eGFR \>90-60 ml/min/1.73 m\^2)
The studies in this group were performed to disclose the changes that occur as a consequence of the beginning of kidney function deterioration.
laboratory parameters - complete blood count
the complete blood count was analyzed using Sysmex K-4500 Automated Hematology Analyzer (by GMI Inc., USA):
* hemoglobin (HGB) \[g/dl\];
* red blood count (RBC) \[10\^12/l\];
* hematocrit (HCT) \[l/l\];
* white blood cells (WBC) \[10\^9/l\];
* platelet count (PLT) \[10\^9/l\]
body mass index (BMI) [kg/m^2] calculation
body mass index (BMI) \[kg/m\^2\] was calculated by dividing a person's weight (post-HD weight in HD group) \[kg\] by the squared their body height \[m\]
selected parameters of oxidative stress (1)
Serum concentration of:
* advanced glycation ends products (AGE) \[µg/mg protein\];
* 3-nitrotyrosine (3-NT) \[µmol/mg protein\];
* advanced oxidation protein products (AOPP) \[µmol/mg protein\];
* carboxymethyle(lysine) (CML) \[µg/mg protein\]
were determined with the enzyme immunoassay methods (ELISA) using Shanghai Sunred Biological Technology Co kits, China.
metalloproteinases
metalloproteinases in the serum \[ng/ml\]:
* metalloproteinase 9 (MMP-9) in the serum was determined by the ELISA method using the Quantikine Human MMP-9 (total) kit, by R\&D Systems, Canada;
* tissue inhibitor of metalloproteinase 1 (TIMP-1) in the serum - was determined by the ELISA method using the Quantikine Human TIMP-1 kit, manufactured by R\&D Systems, Canada;
* the MMP-9/TIMP-1 ratio was calculated by the quotient of the MMP-9 and the TIMP-1 concentration.
parameters of lipids metabolism in the serum
* total cholesterol (T-C) \[mg/dl\] - was assessed by routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA;
* low-density lipoprotein cholesterol (LDL-C) \[mg/dl\] - was assessed by routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA;
* high-density lipoprotein cholesterol (HDL-C) \[mg/dl\] - was assessed by routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA;
* triglycerides (TG) \[mg/dl\] - were assessed by routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA;
* the concentration of low-density lipoprotein (LDL-C) cholesterol - was determined from Friedewalds' equation (LDL-C \[mg/dl\] = total cholesterol (T-C) \[mg/dl\]- HDL-C \[mg/dl\]- TG\[mg/dl\]/5).
parameters of iron metabolism
* iron concentration \[mg/dl\] - was analyzed with the Cobas Integra 400 plus biochemical analyzer from Roche Diagnostics, USA;
* total iron-binding capacity (TIBC) \[mg/dl\] - was analyzed with the Cobas Integra 400 plus biochemical analyzer from Roche Diagnostics, USA;
* the unsaturated iron-binding capacity (UIBC) \[mg/dl\] was determined by an equation in which iron concentration in plasma is subtracted from TIBC \[mg/dl\];
* ferritin \[ng/ml\] concentration was determined with the Modular E-170 biochemical analyzer from Roche Diagnostics, USA.
selected inflammatory markers
* high-sensitivity C-reactive protein (hsCRP) \[mg/l\] was measured using DADE Behring, USA and the DADE nephelometer Behring Analyzer II;
* neopterin \[nmol/l\] was determined by using the Neopterin ELISA kit, DRG International, Inc., USA;
* interleukin 18 (IL-18) \[pg/ml\] concentration was determined by Colorimetric Sandwich ELISA, Quantikine Human IL-18 R\&D Inc., USA.
carotid intima-media thickness (IMT)
carotid intima-media thickness (IMT) \[mm\] was measured by The Accuson CV 70 system (Siemens) with a 10 megahertz (Mhz) transducer.
Two longitudinal projections were assessed (anterolateral and posterolateral). The distal 1 cm of the common carotid artery just proximal to the bulb was measured by means of a computer analysis system (Medical Imaging Applications, LLC).
non-invasive cardiological examinations
For non-invasive cardiological examinations, the Portapres device (Finapres Medical Systems (FMS), the Netherlands), the SphygmoCor tonometer (AtCor Medical), the Colin blood pressure monitor (BMP)-7000 (Japan) were used.
Main assessed variables: heart rate (HR) \[beats per minute \[bpm\]\]; ejection duration (ED) \[millisecons\]; peripheral systolic (pSBP) and diastolic blood pressure (pDBP) \[mm Hg\]; peripheral mean arterial pressure (pMAP) \[mm Hg\]; peripheral end-systolic pressure (pESP) \[mm Hg\]; central systolic (cSBP) and diastolic blood pressure (cDBP) \[mm Hg\]; central mean arterial pressure (cMAP) \[mm Hg\]; central augmented pressure (cAP) \[mmHg\]; central mean pressure of diastole (cMPD)\[mm Hg\]; central mean pressure of systole (cMPS) \[mm Hg\]; central end-systolic pressure (cESP) \[mm Hg\].
vessel stiffness assessment
The following parameters of vessel stiffness were assessed by Pulse Trace 2000 (Micro Medical Ltd., Rochester, Kent, United Kingdom):
* reflection index (RI) \[in percentages \[%\]\];
* vascular stiffness index (SI) \[m/s\];
* peripheral pulse pressure (pPP) \[mm Hg\];
* central puls pressure (cPP) \[mm Hg\]
* peripheral pulse pressure/central pulse pressure (pPP/cPP ratio).
cardiovascular (CV)-related death recording during 2-year follow-up
During a 2-year follow-up from the enrollment to this study, CV-related fatal incidents history has been recorded for each subject separately. The primary endpoint was fatal acute myocardial infarction (AMI) or acute ischemic stroke or any unexpected or sudden death only if autopsy proved CV-related. If there was doubt about the cause of death or there was no contact with the patient during the two years from study enrollment, that patient was excluded and not considered further.
glucose (Glu)
glucose (Glu) \[mg/dl\] was assessed in the serum by a routine technique using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA.
klotho
klotho \[ng/ml\] - was analyzed in the serum by Human KL(Klotho) \[ng/ml\] ELISA Kit, Shanghai Sunred Biological Technology Co kit, China.
fibroblast growth factor 23 (FGF-23)
FGF-23 \[pg/ml\] - was analyzed in rhe serum using Human FGF-23 ELISA Kit, Sigma-Aldrich, USA.
parameters of calcium and phosphate metabolism
* total and ionized calcium \[mg/dl\],
* phosphate \[mg/dl\],
* intact parathormone (iPTH) \[mg/dl\]
were assessed by routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA.
liver enzymes activity assessment
activity of:
* alanine transaminase (ALT) \[U/l\];
* aspartate transaminase (AST) \[U/l\];
* alkaline phosphatase (ALP) \[U/l\]
were assessed by routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA.
total protein and albumin
* total protein (TP) \[g/dl\];
* albumin (ALB) \[g/dl\]
were assessed in the serum by routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA.
creatinine and urea
* creatinine in the serum \[mg/dl\] - the assay is based on the reaction of creatinine with sodium picrate as described by Jaffe (Jaffes' colorimetric method) - was assessed by routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA;
* urea \[mg/dl\] in the serum - was assessed by routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA.
selected parameters of oxidative stress (2)
myeloperoxidase (MPO) \[ng/ml\] in the serum- was determined by the ELISA method using the Quantikine Human MPO test by R\&D Systems kit, Canada.
selected parameters of oxidative stress (3) sRAGE
soluble receptor for advanced glycation end products (sRAGE) \[µg/mg protein\] in the serum was tested with enzymatic immunoassay (Quantikine ELISA) using R\&D Systems kit, Canada.
selected parameters of oxidative stress (4) MG, CEL, carbamyl protein groups
* methylglyoxal (MG) \[µg/mg protein\];
* carboxyethyle(lysine) (CEL) \[µg/mg protein\];
* carbamyl protein groups \[µg/mg protein\] were assessed in the serum by competitive enzyme immunoassay (competitive ELISA) using kits from Cell Biolabs Inc, USA.
selected electrolytes assessment
* potassium (K) \[mmol/l\];
* sodium (Na) \[mmol/l\];
* magnesium (Mg) \[mg/dL\]
were assessed in the serum by routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA.
NT-pro-brain natriuretic peptide (NT-proBNP)
NT-proBNP \[fmol/ml\] - was analyzed in the serum by enzyme immunoassay using the Nt-proBNP kit from Biomedica, Slovakia.
estimated glomerular filtration rate (eGFR) calculation
eGFR \[ml/min/1.73m\^2\] - according to the Kidney Disease: Improving Global Outcomes (KDIGO) 2012 recommendations was calculated based on the Modification of Diet in Renal Disease (MDRD) formula: eGFR = 186 x \[creatinine concentration in mg/dl\] - 1.154 x \[age in years\] - 0.203 x \[0.724\] for the female gender.
Healthy volunteers (HV)
HV (n = 32) - this group was composed of healthy people, with no evidence of impairment in renal function and cardiovascular disorders in the history and at the time of enrollment in the study.
laboratory parameters - complete blood count
the complete blood count was analyzed using Sysmex K-4500 Automated Hematology Analyzer (by GMI Inc., USA):
* hemoglobin (HGB) \[g/dl\];
* red blood count (RBC) \[10\^12/l\];
* hematocrit (HCT) \[l/l\];
* white blood cells (WBC) \[10\^9/l\];
* platelet count (PLT) \[10\^9/l\]
body mass index (BMI) [kg/m^2] calculation
body mass index (BMI) \[kg/m\^2\] was calculated by dividing a person's weight (post-HD weight in HD group) \[kg\] by the squared their body height \[m\]
selected parameters of oxidative stress (1)
Serum concentration of:
* advanced glycation ends products (AGE) \[µg/mg protein\];
* 3-nitrotyrosine (3-NT) \[µmol/mg protein\];
* advanced oxidation protein products (AOPP) \[µmol/mg protein\];
* carboxymethyle(lysine) (CML) \[µg/mg protein\]
were determined with the enzyme immunoassay methods (ELISA) using Shanghai Sunred Biological Technology Co kits, China.
metalloproteinases
metalloproteinases in the serum \[ng/ml\]:
* metalloproteinase 9 (MMP-9) in the serum was determined by the ELISA method using the Quantikine Human MMP-9 (total) kit, by R\&D Systems, Canada;
* tissue inhibitor of metalloproteinase 1 (TIMP-1) in the serum - was determined by the ELISA method using the Quantikine Human TIMP-1 kit, manufactured by R\&D Systems, Canada;
* the MMP-9/TIMP-1 ratio was calculated by the quotient of the MMP-9 and the TIMP-1 concentration.
parameters of lipids metabolism in the serum
* total cholesterol (T-C) \[mg/dl\] - was assessed by routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA;
* low-density lipoprotein cholesterol (LDL-C) \[mg/dl\] - was assessed by routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA;
* high-density lipoprotein cholesterol (HDL-C) \[mg/dl\] - was assessed by routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA;
* triglycerides (TG) \[mg/dl\] - were assessed by routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA;
* the concentration of low-density lipoprotein (LDL-C) cholesterol - was determined from Friedewalds' equation (LDL-C \[mg/dl\] = total cholesterol (T-C) \[mg/dl\]- HDL-C \[mg/dl\]- TG\[mg/dl\]/5).
parameters of iron metabolism
* iron concentration \[mg/dl\] - was analyzed with the Cobas Integra 400 plus biochemical analyzer from Roche Diagnostics, USA;
* total iron-binding capacity (TIBC) \[mg/dl\] - was analyzed with the Cobas Integra 400 plus biochemical analyzer from Roche Diagnostics, USA;
* the unsaturated iron-binding capacity (UIBC) \[mg/dl\] was determined by an equation in which iron concentration in plasma is subtracted from TIBC \[mg/dl\];
* ferritin \[ng/ml\] concentration was determined with the Modular E-170 biochemical analyzer from Roche Diagnostics, USA.
selected inflammatory markers
* high-sensitivity C-reactive protein (hsCRP) \[mg/l\] was measured using DADE Behring, USA and the DADE nephelometer Behring Analyzer II;
* neopterin \[nmol/l\] was determined by using the Neopterin ELISA kit, DRG International, Inc., USA;
* interleukin 18 (IL-18) \[pg/ml\] concentration was determined by Colorimetric Sandwich ELISA, Quantikine Human IL-18 R\&D Inc., USA.
carotid intima-media thickness (IMT)
carotid intima-media thickness (IMT) \[mm\] was measured by The Accuson CV 70 system (Siemens) with a 10 megahertz (Mhz) transducer.
Two longitudinal projections were assessed (anterolateral and posterolateral). The distal 1 cm of the common carotid artery just proximal to the bulb was measured by means of a computer analysis system (Medical Imaging Applications, LLC).
non-invasive cardiological examinations
For non-invasive cardiological examinations, the Portapres device (Finapres Medical Systems (FMS), the Netherlands), the SphygmoCor tonometer (AtCor Medical), the Colin blood pressure monitor (BMP)-7000 (Japan) were used.
Main assessed variables: heart rate (HR) \[beats per minute \[bpm\]\]; ejection duration (ED) \[millisecons\]; peripheral systolic (pSBP) and diastolic blood pressure (pDBP) \[mm Hg\]; peripheral mean arterial pressure (pMAP) \[mm Hg\]; peripheral end-systolic pressure (pESP) \[mm Hg\]; central systolic (cSBP) and diastolic blood pressure (cDBP) \[mm Hg\]; central mean arterial pressure (cMAP) \[mm Hg\]; central augmented pressure (cAP) \[mmHg\]; central mean pressure of diastole (cMPD)\[mm Hg\]; central mean pressure of systole (cMPS) \[mm Hg\]; central end-systolic pressure (cESP) \[mm Hg\].
vessel stiffness assessment
The following parameters of vessel stiffness were assessed by Pulse Trace 2000 (Micro Medical Ltd., Rochester, Kent, United Kingdom):
* reflection index (RI) \[in percentages \[%\]\];
* vascular stiffness index (SI) \[m/s\];
* peripheral pulse pressure (pPP) \[mm Hg\];
* central puls pressure (cPP) \[mm Hg\]
* peripheral pulse pressure/central pulse pressure (pPP/cPP ratio).
cardiovascular (CV)-related death recording during 2-year follow-up
During a 2-year follow-up from the enrollment to this study, CV-related fatal incidents history has been recorded for each subject separately. The primary endpoint was fatal acute myocardial infarction (AMI) or acute ischemic stroke or any unexpected or sudden death only if autopsy proved CV-related. If there was doubt about the cause of death or there was no contact with the patient during the two years from study enrollment, that patient was excluded and not considered further.
glucose (Glu)
glucose (Glu) \[mg/dl\] was assessed in the serum by a routine technique using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA.
klotho
klotho \[ng/ml\] - was analyzed in the serum by Human KL(Klotho) \[ng/ml\] ELISA Kit, Shanghai Sunred Biological Technology Co kit, China.
fibroblast growth factor 23 (FGF-23)
FGF-23 \[pg/ml\] - was analyzed in rhe serum using Human FGF-23 ELISA Kit, Sigma-Aldrich, USA.
parameters of calcium and phosphate metabolism
* total and ionized calcium \[mg/dl\],
* phosphate \[mg/dl\],
* intact parathormone (iPTH) \[mg/dl\]
were assessed by routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA.
liver enzymes activity assessment
activity of:
* alanine transaminase (ALT) \[U/l\];
* aspartate transaminase (AST) \[U/l\];
* alkaline phosphatase (ALP) \[U/l\]
were assessed by routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA.
total protein and albumin
* total protein (TP) \[g/dl\];
* albumin (ALB) \[g/dl\]
were assessed in the serum by routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA.
creatinine and urea
* creatinine in the serum \[mg/dl\] - the assay is based on the reaction of creatinine with sodium picrate as described by Jaffe (Jaffes' colorimetric method) - was assessed by routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA;
* urea \[mg/dl\] in the serum - was assessed by routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA.
selected parameters of oxidative stress (2)
myeloperoxidase (MPO) \[ng/ml\] in the serum- was determined by the ELISA method using the Quantikine Human MPO test by R\&D Systems kit, Canada.
selected parameters of oxidative stress (3) sRAGE
soluble receptor for advanced glycation end products (sRAGE) \[µg/mg protein\] in the serum was tested with enzymatic immunoassay (Quantikine ELISA) using R\&D Systems kit, Canada.
selected parameters of oxidative stress (4) MG, CEL, carbamyl protein groups
* methylglyoxal (MG) \[µg/mg protein\];
* carboxyethyle(lysine) (CEL) \[µg/mg protein\];
* carbamyl protein groups \[µg/mg protein\] were assessed in the serum by competitive enzyme immunoassay (competitive ELISA) using kits from Cell Biolabs Inc, USA.
selected electrolytes assessment
* potassium (K) \[mmol/l\];
* sodium (Na) \[mmol/l\];
* magnesium (Mg) \[mg/dL\]
were assessed in the serum by routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA.
NT-pro-brain natriuretic peptide (NT-proBNP)
NT-proBNP \[fmol/ml\] - was analyzed in the serum by enzyme immunoassay using the Nt-proBNP kit from Biomedica, Slovakia.
estimated glomerular filtration rate (eGFR) calculation
eGFR \[ml/min/1.73m\^2\] - according to the Kidney Disease: Improving Global Outcomes (KDIGO) 2012 recommendations was calculated based on the Modification of Diet in Renal Disease (MDRD) formula: eGFR = 186 x \[creatinine concentration in mg/dl\] - 1.154 x \[age in years\] - 0.203 x \[0.724\] for the female gender.
Interventions
Learn about the drugs, procedures, or behavioral strategies being tested and how they are applied within this trial.
laboratory parameters - complete blood count
the complete blood count was analyzed using Sysmex K-4500 Automated Hematology Analyzer (by GMI Inc., USA):
* hemoglobin (HGB) \[g/dl\];
* red blood count (RBC) \[10\^12/l\];
* hematocrit (HCT) \[l/l\];
* white blood cells (WBC) \[10\^9/l\];
* platelet count (PLT) \[10\^9/l\]
body mass index (BMI) [kg/m^2] calculation
body mass index (BMI) \[kg/m\^2\] was calculated by dividing a person's weight (post-HD weight in HD group) \[kg\] by the squared their body height \[m\]
selected parameters of oxidative stress (1)
Serum concentration of:
* advanced glycation ends products (AGE) \[µg/mg protein\];
* 3-nitrotyrosine (3-NT) \[µmol/mg protein\];
* advanced oxidation protein products (AOPP) \[µmol/mg protein\];
* carboxymethyle(lysine) (CML) \[µg/mg protein\]
were determined with the enzyme immunoassay methods (ELISA) using Shanghai Sunred Biological Technology Co kits, China.
metalloproteinases
metalloproteinases in the serum \[ng/ml\]:
* metalloproteinase 9 (MMP-9) in the serum was determined by the ELISA method using the Quantikine Human MMP-9 (total) kit, by R\&D Systems, Canada;
* tissue inhibitor of metalloproteinase 1 (TIMP-1) in the serum - was determined by the ELISA method using the Quantikine Human TIMP-1 kit, manufactured by R\&D Systems, Canada;
* the MMP-9/TIMP-1 ratio was calculated by the quotient of the MMP-9 and the TIMP-1 concentration.
parameters of lipids metabolism in the serum
* total cholesterol (T-C) \[mg/dl\] - was assessed by routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA;
* low-density lipoprotein cholesterol (LDL-C) \[mg/dl\] - was assessed by routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA;
* high-density lipoprotein cholesterol (HDL-C) \[mg/dl\] - was assessed by routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA;
* triglycerides (TG) \[mg/dl\] - were assessed by routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA;
* the concentration of low-density lipoprotein (LDL-C) cholesterol - was determined from Friedewalds' equation (LDL-C \[mg/dl\] = total cholesterol (T-C) \[mg/dl\]- HDL-C \[mg/dl\]- TG\[mg/dl\]/5).
parameters of iron metabolism
* iron concentration \[mg/dl\] - was analyzed with the Cobas Integra 400 plus biochemical analyzer from Roche Diagnostics, USA;
* total iron-binding capacity (TIBC) \[mg/dl\] - was analyzed with the Cobas Integra 400 plus biochemical analyzer from Roche Diagnostics, USA;
* the unsaturated iron-binding capacity (UIBC) \[mg/dl\] was determined by an equation in which iron concentration in plasma is subtracted from TIBC \[mg/dl\];
* ferritin \[ng/ml\] concentration was determined with the Modular E-170 biochemical analyzer from Roche Diagnostics, USA.
selected inflammatory markers
* high-sensitivity C-reactive protein (hsCRP) \[mg/l\] was measured using DADE Behring, USA and the DADE nephelometer Behring Analyzer II;
* neopterin \[nmol/l\] was determined by using the Neopterin ELISA kit, DRG International, Inc., USA;
* interleukin 18 (IL-18) \[pg/ml\] concentration was determined by Colorimetric Sandwich ELISA, Quantikine Human IL-18 R\&D Inc., USA.
carotid intima-media thickness (IMT)
carotid intima-media thickness (IMT) \[mm\] was measured by The Accuson CV 70 system (Siemens) with a 10 megahertz (Mhz) transducer.
Two longitudinal projections were assessed (anterolateral and posterolateral). The distal 1 cm of the common carotid artery just proximal to the bulb was measured by means of a computer analysis system (Medical Imaging Applications, LLC).
non-invasive cardiological examinations
For non-invasive cardiological examinations, the Portapres device (Finapres Medical Systems (FMS), the Netherlands), the SphygmoCor tonometer (AtCor Medical), the Colin blood pressure monitor (BMP)-7000 (Japan) were used.
Main assessed variables: heart rate (HR) \[beats per minute \[bpm\]\]; ejection duration (ED) \[millisecons\]; peripheral systolic (pSBP) and diastolic blood pressure (pDBP) \[mm Hg\]; peripheral mean arterial pressure (pMAP) \[mm Hg\]; peripheral end-systolic pressure (pESP) \[mm Hg\]; central systolic (cSBP) and diastolic blood pressure (cDBP) \[mm Hg\]; central mean arterial pressure (cMAP) \[mm Hg\]; central augmented pressure (cAP) \[mmHg\]; central mean pressure of diastole (cMPD)\[mm Hg\]; central mean pressure of systole (cMPS) \[mm Hg\]; central end-systolic pressure (cESP) \[mm Hg\].
vessel stiffness assessment
The following parameters of vessel stiffness were assessed by Pulse Trace 2000 (Micro Medical Ltd., Rochester, Kent, United Kingdom):
* reflection index (RI) \[in percentages \[%\]\];
* vascular stiffness index (SI) \[m/s\];
* peripheral pulse pressure (pPP) \[mm Hg\];
* central puls pressure (cPP) \[mm Hg\]
* peripheral pulse pressure/central pulse pressure (pPP/cPP ratio).
cardiovascular (CV)-related death recording during 2-year follow-up
During a 2-year follow-up from the enrollment to this study, CV-related fatal incidents history has been recorded for each subject separately. The primary endpoint was fatal acute myocardial infarction (AMI) or acute ischemic stroke or any unexpected or sudden death only if autopsy proved CV-related. If there was doubt about the cause of death or there was no contact with the patient during the two years from study enrollment, that patient was excluded and not considered further.
glucose (Glu)
glucose (Glu) \[mg/dl\] was assessed in the serum by a routine technique using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA.
klotho
klotho \[ng/ml\] - was analyzed in the serum by Human KL(Klotho) \[ng/ml\] ELISA Kit, Shanghai Sunred Biological Technology Co kit, China.
fibroblast growth factor 23 (FGF-23)
FGF-23 \[pg/ml\] - was analyzed in rhe serum using Human FGF-23 ELISA Kit, Sigma-Aldrich, USA.
parameters of calcium and phosphate metabolism
* total and ionized calcium \[mg/dl\],
* phosphate \[mg/dl\],
* intact parathormone (iPTH) \[mg/dl\]
were assessed by routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA.
liver enzymes activity assessment
activity of:
* alanine transaminase (ALT) \[U/l\];
* aspartate transaminase (AST) \[U/l\];
* alkaline phosphatase (ALP) \[U/l\]
were assessed by routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA.
total protein and albumin
* total protein (TP) \[g/dl\];
* albumin (ALB) \[g/dl\]
were assessed in the serum by routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA.
creatinine and urea
* creatinine in the serum \[mg/dl\] - the assay is based on the reaction of creatinine with sodium picrate as described by Jaffe (Jaffes' colorimetric method) - was assessed by routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA;
* urea \[mg/dl\] in the serum - was assessed by routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA.
selected parameters of oxidative stress (2)
myeloperoxidase (MPO) \[ng/ml\] in the serum- was determined by the ELISA method using the Quantikine Human MPO test by R\&D Systems kit, Canada.
selected parameters of oxidative stress (3) sRAGE
soluble receptor for advanced glycation end products (sRAGE) \[µg/mg protein\] in the serum was tested with enzymatic immunoassay (Quantikine ELISA) using R\&D Systems kit, Canada.
selected parameters of oxidative stress (4) MG, CEL, carbamyl protein groups
* methylglyoxal (MG) \[µg/mg protein\];
* carboxyethyle(lysine) (CEL) \[µg/mg protein\];
* carbamyl protein groups \[µg/mg protein\] were assessed in the serum by competitive enzyme immunoassay (competitive ELISA) using kits from Cell Biolabs Inc, USA.
selected electrolytes assessment
* potassium (K) \[mmol/l\];
* sodium (Na) \[mmol/l\];
* magnesium (Mg) \[mg/dL\]
were assessed in the serum by routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA.
NT-pro-brain natriuretic peptide (NT-proBNP)
NT-proBNP \[fmol/ml\] - was analyzed in the serum by enzyme immunoassay using the Nt-proBNP kit from Biomedica, Slovakia.
estimated glomerular filtration rate (eGFR) calculation
eGFR \[ml/min/1.73m\^2\] - according to the Kidney Disease: Improving Global Outcomes (KDIGO) 2012 recommendations was calculated based on the Modification of Diet in Renal Disease (MDRD) formula: eGFR = 186 x \[creatinine concentration in mg/dl\] - 1.154 x \[age in years\] - 0.203 x \[0.724\] for the female gender.
Eligibility Criteria
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Inclusion Criteria
in group HD:
* a minimum of 6 months of treatment with repeated hemodialysis, 3 times a week, for a minimum of 10 hours a week,
* arteriovenous fistula as a vascular access for hemodialysis,
* Estimated dialysis adequacy ratio (eKt / V) of at least 1.2. in the PD group:
* treatment duration UP to a minimum of 6 months, Kt / V ≥1.8 l / week / 1.73 m2.
For CARD patients, additional conditions include:
* no obvious evidence of renal impairment in the history and at the time of study entry, renal function assessed on the basis of eGFR and urine albumin/creatinine ratio,
* history of angina pectoris,
* documented history of at least one acute coronary syndrome,
* admission to the Department of Intensive Care of Cardiology and Internal Diseases in order to perform a planned coronary angiography, on the day of admission to the study without signs of the acute coronary syndrome, no additional comorbidities, ie those that do not result directly or indirectly from coronary heart disease.
In turn, for the HV group (control group), additional conditions include:
* no obvious evidence of renal impairment in the history and at the time of study entry, renal function assessed on the basis of eGFR and urine albumin/creatinine ratio,
* no obvious signs of cardiovascular impairment in the history and at the time of study entry, estimated on the basis of normal blood pressure (\<140/90 mmHg), no abnormalities in the medical history and physical examination,
* not taking any medications on a regular basis.
18 Years
ALL
Yes
Sponsors
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Poznan University of Medical Sciences
OTHER
Responsible Party
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Dorota Formanowicz
MD.Ph.D. Associate Professor
Principal Investigators
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Dorota Formanowicz, MD, PhD
Role: PRINCIPAL_INVESTIGATOR
Poznan University of Mediccal Sciences
Locations
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Poznan University of Medical Sciences
Poznan, , Poland
Countries
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References
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Twardawa M, Formanowicz P, Formanowicz D. Chronic Kidney Disease as a Cardiovascular Disorder-Tonometry Data Analyses. Int J Environ Res Public Health. 2022 Sep 28;19(19):12339. doi: 10.3390/ijerph191912339.
Kasprzak L, Twardawa M, Formanowicz P, Formanowicz D. The Mutual Contribution of 3-NT, IL-18, Albumin, and Phosphate Foreshadows Death of Hemodialyzed Patients in a 2-Year Follow-Up. Antioxidants (Basel). 2022 Feb 11;11(2):355. doi: 10.3390/antiox11020355.
Other Identifiers
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PoznanUMS_DF2
Identifier Type: -
Identifier Source: org_study_id