The Impact of Selected Factors on the Cardiovascular System in Chronic Kidney Disease

Completed

• Conditions: Inflammation; Chronic Kidney Diseases; Cardiovascular Diseases; Atherosclerosis of Artery; Dialysis; Complications
• Interventions: Diagnostic Test: laboratory parameters - complete blood count; Other: body mass index (BMI) [kg/m^2] calculation; Diagnostic Test: selected parameters of oxidative stress (1); Diagnostic Test: metalloproteinases; Diagnostic Test: parameters of lipids metabolism in the serum; Diagnostic Test: parameters of iron metabolism; Diagnostic Test: selected inflammatory markers; Device: carotid intima-media thickness (IMT); Device: non-invasive cardiological examinations; Device: vessel stiffness assessment; Other: cardiovascular (CV)-related death recording during 2-year follow-up; Diagnostic Test: glucose (Glu); Diagnostic Test: klotho; Diagnostic Test: fibroblast growth factor 23 (FGF-23); Diagnostic Test: parameters of calcium and phosphate metabolism; Diagnostic Test: liver enzymes activity assessment; Diagnostic Test: total protein and albumin; Diagnostic Test: creatinine and urea; Diagnostic Test: selected parameters of oxidative stress (2); Diagnostic Test: selected parameters of oxidative stress (3) sRAGE; Diagnostic Test: selected parameters of oxidative stress (4) MG, CEL, carbamyl protein groups; Diagnostic Test: selected electrolytes assessment; Diagnostic Test: NT-pro-brain natriuretic peptide (NT-proBNP); Other: estimated glomerular filtration rate (eGFR) calculation

• Registration Number: NCT05214872
• Lead Sponsor: Poznan University of Medical Sciences

Brief Summary

Chronic kidney disease (CKD), is characterized by accelerated development of atherosclerosis and advanced remodelling of vessels and the heart. It is associated with many factors, including inflammation, arterial hypertension, hyperlipidemia, hyperhomocysteinemia, secondary hyperparathyroidism, and oxidative stress. Hypertension is one of the most critical risk factors for cardiovascular complications. It leads to the formation of structural changes in the vascular system: it impairs the activity of the endothelium, causes hypertrophy and remodelling of the vascular wall, reduces the susceptibility of the vessels and accelerates the development of atherosclerosis. This study aimed to identify the processes and their representative markers, the concentration of which in the serum may reflect the cardiovascular system status and can predict the increased mortality in HD patients.

Detailed Description

Chronic Kidney Disease has a significant impact on the cardiovascular system. From many different complications of CKD, one to mention is arterial stiffness. This disorder results from many pathologies, including inflammation, arterial hypertension, carbohydrate metabolic disorders, lipid disorders, vascular calcification, chronic inflammation, and oxidative stress.

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.

Study Timeline

• Study Start: 2016-03-25
• Primary Completion: 2020-09-10
• Study Completion: 2020-09-30
• Study First Submitted: 2021-12-09
• Status Verified: 2022-01
• Study First Submitted QC: 2022-01-25
• Last Update Submitted: 2022-01-25
• Study First Posted: 2022-01-31
• Last Update Posted: 2022-01-31

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 252

Inclusion Criteria

Not provided

Exclusion Criteria

Not provided

Study & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Arm && Interventions

Group	Intervention	Description
PREDIALYSIS GROUP	metalloproteinases	(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)
PREDIALYSIS GROUP	selected parameters of oxidative stress (2)	(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)
PREDIALYSIS GROUP	selected parameters of oxidative stress (1)	(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)
PREDIALYSIS GROUP	parameters of lipids metabolism in the serum	(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)
PREDIALYSIS GROUP	laboratory parameters - complete blood count	(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)
PREDIALYSIS GROUP	body mass index (BMI) [kg/m^2] calculation	(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)
PREDIALYSIS GROUP	carotid intima-media thickness (IMT)	(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)
PREDIALYSIS GROUP	parameters of iron metabolism	(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)
PREDIALYSIS GROUP	selected inflammatory markers	(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)
PREDIALYSIS GROUP	selected electrolytes assessment	(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)
PREDIALYSIS GROUP	NT-pro-brain natriuretic peptide (NT-proBNP)	(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)
PREDIALYSIS GROUP	non-invasive cardiological examinations	(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)
PREDIALYSIS GROUP	klotho	(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)
END-STAGE RENAL DISEASE (ESRD) GROUP	metalloproteinases	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.
END-STAGE RENAL DISEASE (ESRD) GROUP	carotid intima-media thickness (IMT)	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.
PREDIALYSIS GROUP	vessel stiffness assessment	(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)
PREDIALYSIS GROUP	cardiovascular (CV)-related death recording during 2-year follow-up	(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)
PREDIALYSIS GROUP	liver enzymes activity assessment	(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)
PREDIALYSIS GROUP	total protein and albumin	(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)
END-STAGE RENAL DISEASE (ESRD) GROUP	body mass index (BMI) [kg/m^2] calculation	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.
END-STAGE RENAL DISEASE (ESRD) GROUP	glucose (Glu)	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.
PREDIALYSIS GROUP	glucose (Glu)	(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)
PREDIALYSIS GROUP	fibroblast growth factor 23 (FGF-23)	(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)
PREDIALYSIS GROUP	parameters of calcium and phosphate metabolism	(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)
PREDIALYSIS GROUP	creatinine and urea	(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)
PREDIALYSIS GROUP	selected parameters of oxidative stress (3) sRAGE	(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)
PREDIALYSIS GROUP	selected parameters of oxidative stress (4) MG, CEL, carbamyl protein groups	(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)
PREDIALYSIS GROUP	estimated glomerular filtration rate (eGFR) calculation	(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)
END-STAGE RENAL DISEASE (ESRD) GROUP	parameters of iron metabolism	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.
END-STAGE RENAL DISEASE (ESRD) GROUP	laboratory parameters - complete blood count	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.
END-STAGE RENAL DISEASE (ESRD) GROUP	vessel stiffness assessment	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.
END-STAGE RENAL DISEASE (ESRD) GROUP	cardiovascular (CV)-related death recording during 2-year follow-up	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.
END-STAGE RENAL DISEASE (ESRD) GROUP	fibroblast growth factor 23 (FGF-23)	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.
END-STAGE RENAL DISEASE (ESRD) GROUP	selected parameters of oxidative stress (1)	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.
END-STAGE RENAL DISEASE (ESRD) GROUP	parameters of lipids metabolism in the serum	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.
END-STAGE RENAL DISEASE (ESRD) GROUP	selected inflammatory markers	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.
END-STAGE RENAL DISEASE (ESRD) GROUP	klotho	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.
END-STAGE RENAL DISEASE (ESRD) GROUP	non-invasive cardiological examinations	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.
END-STAGE RENAL DISEASE (ESRD) GROUP	selected parameters of oxidative stress (3) sRAGE	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.
CARDIOLOGY (CARD) GROUP	selected parameters of oxidative stress (1)	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.
CARDIOLOGY (CARD) GROUP	glucose (Glu)	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.
CARDIOLOGY (CARD) GROUP	klotho	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.
END-STAGE RENAL DISEASE (ESRD) GROUP	parameters of calcium and phosphate metabolism	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.
END-STAGE RENAL DISEASE (ESRD) GROUP	total protein and albumin	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.
END-STAGE RENAL DISEASE (ESRD) GROUP	selected parameters of oxidative stress (2)	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.
END-STAGE RENAL DISEASE (ESRD) GROUP	NT-pro-brain natriuretic peptide (NT-proBNP)	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.
END-STAGE RENAL DISEASE (ESRD) GROUP	estimated glomerular filtration rate (eGFR) calculation	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.
END-STAGE RENAL DISEASE (ESRD) GROUP	liver enzymes activity assessment	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.
END-STAGE RENAL DISEASE (ESRD) GROUP	creatinine and urea	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.
CARDIOLOGY (CARD) GROUP	body mass index (BMI) [kg/m^2] calculation	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.
CARDIOLOGY (CARD) GROUP	parameters of lipids metabolism in the serum	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.
CARDIOLOGY (CARD) GROUP	carotid intima-media thickness (IMT)	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.
END-STAGE RENAL DISEASE (ESRD) GROUP	selected parameters of oxidative stress (4) MG, CEL, carbamyl protein groups	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.
END-STAGE RENAL DISEASE (ESRD) GROUP	selected electrolytes assessment	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.
CARDIOLOGY (CARD) GROUP	laboratory parameters - complete blood count	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.
CARDIOLOGY (CARD) GROUP	metalloproteinases	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.
CARDIOLOGY (CARD) GROUP	selected inflammatory markers	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.
CARDIOLOGY (CARD) GROUP	parameters of iron metabolism	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.
CARDIOLOGY (CARD) GROUP	non-invasive cardiological examinations	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.
CARDIOLOGY (CARD) GROUP	fibroblast growth factor 23 (FGF-23)	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.
CARDIOLOGY (CARD) GROUP	total protein and albumin	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.
CARDIOLOGY (CARD) GROUP	creatinine and urea	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.
CARDIOLOGY (CARD) GROUP	vessel stiffness assessment	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.
CARDIOLOGY (CARD) GROUP	selected electrolytes assessment	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.
Chronic kidney disease (CKD) 1-2 GROUP	laboratory parameters - complete blood count	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.
Chronic kidney disease (CKD) 1-2 GROUP	body mass index (BMI) [kg/m^2] calculation	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.
Chronic kidney disease (CKD) 1-2 GROUP	carotid intima-media thickness (IMT)	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.
Chronic kidney disease (CKD) 1-2 GROUP	vessel stiffness assessment	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.
CARDIOLOGY (CARD) GROUP	cardiovascular (CV)-related death recording during 2-year follow-up	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.
CARDIOLOGY (CARD) GROUP	parameters of calcium and phosphate metabolism	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.
CARDIOLOGY (CARD) GROUP	selected parameters of oxidative stress (2)	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.
CARDIOLOGY (CARD) GROUP	selected parameters of oxidative stress (3) sRAGE	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.
Chronic kidney disease (CKD) 1-2 GROUP	selected parameters of oxidative stress (1)	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.
Chronic kidney disease (CKD) 1-2 GROUP	metalloproteinases	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.
CARDIOLOGY (CARD) GROUP	liver enzymes activity assessment	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.
CARDIOLOGY (CARD) GROUP	NT-pro-brain natriuretic peptide (NT-proBNP)	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.
Chronic kidney disease (CKD) 1-2 GROUP	selected parameters of oxidative stress (2)	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.
Healthy volunteers (HV)	selected parameters of oxidative stress (1)	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.
CARDIOLOGY (CARD) GROUP	selected parameters of oxidative stress (4) MG, CEL, carbamyl protein groups	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.
CARDIOLOGY (CARD) GROUP	estimated glomerular filtration rate (eGFR) calculation	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.
Chronic kidney disease (CKD) 1-2 GROUP	parameters of lipids metabolism in the serum	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.
Chronic kidney disease (CKD) 1-2 GROUP	parameters of iron metabolism	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.
Chronic kidney disease (CKD) 1-2 GROUP	non-invasive cardiological examinations	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.
Chronic kidney disease (CKD) 1-2 GROUP	cardiovascular (CV)-related death recording during 2-year follow-up	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.
Chronic kidney disease (CKD) 1-2 GROUP	selected inflammatory markers	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.
Chronic kidney disease (CKD) 1-2 GROUP	klotho	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.
Chronic kidney disease (CKD) 1-2 GROUP	total protein and albumin	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.
Chronic kidney disease (CKD) 1-2 GROUP	creatinine and urea	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.
Chronic kidney disease (CKD) 1-2 GROUP	glucose (Glu)	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.
Chronic kidney disease (CKD) 1-2 GROUP	parameters of calcium and phosphate metabolism	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.
Chronic kidney disease (CKD) 1-2 GROUP	liver enzymes activity assessment	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.
Chronic kidney disease (CKD) 1-2 GROUP	selected electrolytes assessment	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.
Healthy volunteers (HV)	liver enzymes activity assessment	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.
Chronic kidney disease (CKD) 1-2 GROUP	fibroblast growth factor 23 (FGF-23)	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.
Chronic kidney disease (CKD) 1-2 GROUP	selected parameters of oxidative stress (4) MG, CEL, carbamyl protein groups	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.
Healthy volunteers (HV)	body mass index (BMI) [kg/m^2] calculation	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.
Healthy volunteers (HV)	metalloproteinases	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.
Healthy volunteers (HV)	parameters of lipids metabolism in the serum	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.
Healthy volunteers (HV)	non-invasive cardiological examinations	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.
Healthy volunteers (HV)	vessel stiffness assessment	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.
Chronic kidney disease (CKD) 1-2 GROUP	estimated glomerular filtration rate (eGFR) calculation	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.
Healthy volunteers (HV)	laboratory parameters - complete blood count	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.
Healthy volunteers (HV)	glucose (Glu)	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.
Healthy volunteers (HV)	klotho	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.
Healthy volunteers (HV)	fibroblast growth factor 23 (FGF-23)	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.
Healthy volunteers (HV)	total protein and albumin	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.
Chronic kidney disease (CKD) 1-2 GROUP	selected parameters of oxidative stress (3) sRAGE	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.
Chronic kidney disease (CKD) 1-2 GROUP	NT-pro-brain natriuretic peptide (NT-proBNP)	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.
Healthy volunteers (HV)	selected inflammatory markers	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.
Healthy volunteers (HV)	carotid intima-media thickness (IMT)	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.
Healthy volunteers (HV)	cardiovascular (CV)-related death recording during 2-year follow-up	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.
Healthy volunteers (HV)	parameters of calcium and phosphate metabolism	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.
Healthy volunteers (HV)	selected parameters of oxidative stress (2)	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.
Healthy volunteers (HV)	parameters of iron metabolism	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.
Healthy volunteers (HV)	NT-pro-brain natriuretic peptide (NT-proBNP)	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.
Healthy volunteers (HV)	creatinine and urea	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.
Healthy volunteers (HV)	selected electrolytes assessment	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.
Healthy volunteers (HV)	estimated glomerular filtration rate (eGFR) calculation	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.
Healthy volunteers (HV)	selected parameters of oxidative stress (3) sRAGE	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.
Healthy volunteers (HV)	selected parameters of oxidative stress (4) MG, CEL, carbamyl protein groups	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.

Primary Outcome Measures

Name	Time	Method
Diagnostic test: parameters of iron metabolism - total iron-binding capacity (TIBC)	3 years	total iron-binding capacity (TIBC) \[mg/dl\] - was determined with the Cobas Integra 400 plus biochemical analyzer from Roche Diagnostics, USA.
Diagnostic test: basic biochemical parameters: complete blood count - hemoglobin (HGB)	3 years	hemoglobin (HGB) \[g/dl\] was analyzed using Sysmex K-4500 Automated Hematology Analyzer (by GMI Inc., USA).
Diagnostic test: basic biochemical parameters: complete blood count - white blood cell count (WBC)	3 years	white blood cells (WBC) \[10\^9/l\] was analyzed using Sysmex K-4500 Automated Hematology Analyzer (by GMI Inc., USA).
Diagnostic test: liver enzymes activity assessment - alkaline phosphatase (ALP) [U/l]	3 years	activity of alkaline phosphatase (ALP) \[U/l\] was assessed in the serum by the routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA.
Diagnostic test: intact parathormone (iPTH)	3 years	intact parathormone (iPTH) \[mg/dl\] serum concentration was assessed by the routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA.
Diagnostic Test: selected inflammatory markers - interleukin 18 (IL-18)	3 years	interleukin 18 (IL-18) \[pg/ml\] concentration in the serum was determined by Colorimetric Sandwich ELISA, Quantikine Human IL-18 R\&D Inc., USA.
Device: vessel stiffness assessments - peripheral pulse pressure/central pulse pressure (pPP/cPP) ratio	3 years	Peripheral pulse pressure/central pulse pressure (pPP/cPP) ratio was assessed by dividing peripheral pulse pressure (pPP) \[mm Hg\] by central pulse pressure (cPP) \[mm Hg\].
Diagnostic test: basic biochemical parameters: complete blood count - hematocrit (HCT)	3 years	hematocrit (HCT) \[l/l\] was analyzed using Sysmex K-4500 Automated Hematology Analyzer (by GMI Inc., USA).
Diagnostic test: basic biochemical parameters: complete blood count - platelet count (PLT)	3 years	platelet count (PLT) \[10\^9/l\] was analyzed using Sysmex K-4500 Automated Hematology Analyzer (by GMI Inc., USA).
Diagnostic test: urea	3 years	urea \[mg/dl\] concentration in the serum was assessed by the routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA.
Estimated glomerular filtration rate (eGFR) [ml/min/1.73m^2] calculation	3 years	eGFR - 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.
Diagnostic test: parameters of lipids metabolism in the serum low-density lipoprotein cholesterol (LDL-C).	3 years	low-density lipoprotein (LDL-C) cholesterol concentration in the serum was determined from Friedewals' equation (LDL-C \[mg/dl\] = total cholesterol (T-C) \[mg/dl\] - HDL-C \[mg/dl\] - TG\[mg/dl\]/5).; It was assessed by the routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA.
Diagnostic test: parameters of iron metabolism - iron	3 years	iron concentration \[mg/dl\] in the serum - was assessed with the Cobas Integra 400 plus biochemical analyzer from Roche Diagnostics, USA;
Diagnostic test: basic biochemical parameters: complete blood count - red blood cell count (RBC)	3 years	red blood cell count (RBC) \[10\^12/l\] was analyzed using Sysmex K-4500 Automated Hematology Analyzer (by GMI Inc., USA).
Body mass index (BMI) [kg/m^2] calculation	3 years	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 \[m\].
Diagnostic test: parameters of lipids metabolism in the serum - triglycerides (TG)	3 years	triglycerides (TG) \[mg/dl\] concentration in the serum was assessed by the routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA.
Diagnostic test: glucose (Glu)	3 years	glucose (Glu) \[mg/dl\] concentration in the serum was assessed by the routine technique using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA.
Diagnostic test: parameters of lipids metabolism in the serum - total cholesterol (T-C)	3 years	total cholesterol (T-C) \[mg/dl\] concentration in the serum was assessed by routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA.
Diagnostic test: parameters of lipids metabolism in the serum - high-density lipoprotein cholesterol (HDL-C)	3 years	high-density lipoprotein cholesterol (HDL-C) \[mg/dl\] concentration in the serum was assessed by routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA.
Diagnostic test: total protein (TP)	3 years	total protein (TP) \[g/dl\] concentration in the serum was assessed by routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA.
Diagnostic test: albumin(ALB)	3 years	albumin (ALB) \[g/dl\] concentration in the serum was assessed by the routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA.
Diagnostic test: parameters of iron metabolism - ferritin	3 years	ferritin \[ng/ml\] concentration in the serum was determined with the Modular E-170 biochemical analyzer from Roche Diagnostics, USA.
Diagnostic test: total and ionized calcium	3 years	total and ionized calcium \[mg/dl\] serum concentrations were assessed by routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA.
Diagnostic test: fibroblast growth factor 23 (FGF-23)	3 years	fibroblast growth factor 23 (FGF-23) \[pg/ml\] serum concentration was analyzed using Human FGF-23 ELISA Kit, Sigma-Aldrich, USA.
Diagnostic test: creatinine	3 years	creatinine \[mg/dl\] concentration in the serum was assessed by routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA (based on Jaffes' colorimetric method - the assay is based on the reaction of creatinine with sodium picrate as described by Jaffe).
Diagnostic test: liver enzymes activity assessment - aspartate transaminase (AST)	3 years	activity of aspartate transaminase (AST) \[U/l\]; was assessed in the serum by the routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA.
Diagnostic test: liver enzymes activity assessment - alanine transaminase (ALT)	3 years	activity of alanine transaminase (ALT) \[U/l\] was assessed in the serum by the routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA.
Diagnostic test: parameters of iron metabolism - the unsaturated iron-binding capacity (UIBC)	3 years	unsaturated iron-binding capacity (UIBC) \[mg/dl\] was determined by an equation in which iron \[mg/dl\] concentration in plasma is subtracted from TIBC \[mg/dl\].
Diagnostic test: selected electrolytes assessment in the serum: magnesium	3 years	magnesium (Mg) \[mg/dl\] serum concentration was assessed by routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA.
Diagnostic test: metalloproteinases - tissue inhibitor of metalloproteinase 1 (TIMP-1)	3 years	tissue inhibitor of metalloproteinase 1 (TIMP-1) \[ng/ml\] concentration in the serum - was determined by the ELISA method using the Quantikine Human TIMP-1 kit, manufactured by R\&D Systems, Canada.
Diagnostic test: N-terminal pro-B-type natriuretic peptide (NT-proBNP)	3 years	N-terminal pro-B-type natriuretic peptide (NT-proBNP) \[fmol/ml\] concentration in the serum was analyzed by enzyme immunoassay using the Nt-proBNP kit from Biomedica, Slovakia.
Diagnostic test: klotho (KL)	3 years	klotho (KL) \[ng/ml\] serum concentration was analyzed by Human KL(Klotho) \[ng/ml\] ELISA Kit, Shanghai Sunred Biological Technology Co kit, China.
Diagnostic test: selected inflammatory markers - high-sensivity C-reactive protein (hsCRP)	3 years	high-sensitivity C-reactive protein (hsCRP) \[mg/l\] concentration in the serum was measured using DADE Behring, USA, and the DADE nephelometer Behring Analyzer II.
Diagnostic test: selected inflammatory markers - neopterin	3 years	neopterin \[nmol/l\] serum concentration was determined by using the Neopterin ELISA kit, DRG International, Inc., USA.
Diagnostic test: selected parameters of oxidative stress - carboxyethyle(lysine) (CEL) [µg/mg protein]	3 years	carboxyethyle(lysine) (CEL) \[µg/mg protein\] concentration in the serum was assessed by competitive enzyme immunoassay (competitive ELISA) using CEL kits from Cell Biolabs Inc, USA.
Diagnostic test: selected parameters of oxidative stress - carbamyl protein groups [µg/mg protein]	3 years	carbamyl protein groups \[µg/mg protein\] concentration in the serum were assessed by competitive enzyme immunoassay (competitive ELISA) using carbamyl protein groups kits from Cell Biolabs Inc, USA.
Diagnostic test: selected parameters of oxidative stress - soluble receptor for advanced glycation end products (sRAGE)	3 years	soluble receptor for advanced glycation end products (sRAGE) \[µg/mg protein\] concentration in the serum was tested with enzymatic immunoassay (Quantikine ELISA) using R\&D Systems sRAGE kit, Canada.
Device: vessel stiffness assessments - vascular stiffness index (SI)	3 years	The following parameter of vessel stiffness was assessed by Pulse Trace 2000 (Micro Medical Ltd., Rochester, Kent, United Kingdom): -vascular stiffness index (SI) \[m/s\].
Diagnostic test: phosphate	3 years	phosphate \[mg/dl\] serum concentration was assessed by the routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA.
Diagnostic test: selected electrolytes assessment in the serum: potassium (K) and sodium (Na)	3 years	Electrolytes: potassium (K) \[mmol/l\] and sodium (Na) \[mmol/l\] serum concentrations were assessed by the routine techniques using Cobas Integra 400 plus biochemical analyzer by Roche Diagnostics, USA.
Diagnostic test: selected parameters of oxidative stress - 3-nitrotyrosine (3-NT)	3 years	Serum concentration of 3-nitrotyrosine (3-NT) \[µmol/mg protein\] was determined with the enzyme immunoassay method (ELISA) for 3NT using Shanghai Sunred Biological Technology Co kits, China.
Diagnostic test: selected parameters of oxidative stress - carboxymethyle(lysine) (CML)	3 years	Serum concentration of carboxymethyle(lysine) (CML) \[µg/mg protein\] was determined with the enzyme immunoassay method (ELISA) for CML using Shanghai Sunred Biological Technology Co kits, China.
Non-invasive cardiological examinations (2) with the use of Portapres device (Finapres Medical Systems (FMS), the Netherlands), the SphygmoCor tonometer (AtCor Medical), the Colin blood pressure monitor (BMP)-7000 (Japan) - heart rate (HR)	3 years	Blood pressure was measured using the Colin BPM 7000 on both arms (participants were seated). Next, a piezoelectric tonometer Colin BPM was placed over the radial artery for the acquisition of the radial arterial pressure waveform in a supine position. This signal was sent to the SphygmoCor and after averaging various parameters have been assessed and recorded: - heart rate (HR) in beats per minute \[bpm\]
Diagnostic test: selected parameters of oxidative stress - advanced glycation ends products (AGE)	3 years	Serum concentration of advanced glycation ends products (AGE) \[µg/mg protein\] was determined with the enzyme immunoassay method (ELISA) for AGE using Shanghai Sunred Biological Technology Co kits, China.
Diagnostic test: selected parameters of oxidative stress - advanced oxidation protein products (AOPP)	3 years	Serum concentration of advanced oxidation protein products (AOPP) \[µmol/mg protein\] was determined with the enzyme immunoassay method (ELISA) for AOPP using Shanghai Sunred Biological Technology Co kits, China.
Diagnostic test: metalloproteinases - metalloproteinase 9 (MMP-9)	3 years	metalloproteinase 9 (MMP-9) \[ng/ml\] concentration in the serum was determined by the ELISA method using the Quantikine Human MMP-9 (total) kit, by R\&D Systems, Canada.
The MMP-9/TIMP-1 ratio assessment	3 years	the MMP-9/TIMP-1 ratio was calculated by the quotient of the MMP-9 \[ng/ml\] and the TIMP-1 \[ng/ml\] concentration.
Diagnostic test: selected parameters of oxidative stress - myeloperoxidase (MPO)	3 years	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.
Diagnostic test: selected parameters of oxidative stress - methylglyoxal (MG)	3 years	methylglyoxal (MG) \[µg/mg protein\] concentration in the serum was assessed by competitive enzyme immunoassay (competitive ELISA) using MG kits from Cell Biolabs Inc, USA.
Non-invasive cardiological examinations (1) with the use of Portapres device (Finapres Medical Systems (FMS), the Netherlands), the SphygmoCor tonometer (AtCor Medical), the Colin blood pressure monitor (BMP)-7000 (Japan) - blood pressures	3 years	Blood pressure was measured using the Colin BPM 7000 on both arms (participants were seated). Next, a piezoelectric tonometer Colin BPM was placed over the radial artery for the acquisition of the radial arterial pressure waveform in a supine position. This signal was sent to the SphygmoCor and after averaging various parameters have been assessed and recorded: * peripheral systolic blood pressure (sSBP) \[mmHg\]; * peripheral diastolic blood pressure (pDBP)\[mm Hg\]; * peripheral mean arterial pressure (pMAP) \[mm Hg\]; * peripheral end-systolic pressure (pESP) \[mm Hg\]; * central systolic blood pressure (cSBP) \[mm Hg\]; * central diastolic blood pressure (cDBP) \[mm Hg\]; * central mean arterial pressure (cMAP) \[mm Hg\]; * entral augmented pressure (cAP) \[mm Hg\]; * central mean pressure of diastole (cMPD) \[mm Hg\]; * central mean pressure of systole (cMPS)\[mm Hg\]; * central end-systolic pressure (cESP)\[mm Hg\]
Non-invasive cardiological examinations (3) with the use of Portapres device (Finapres Medical Systems (FMS), the Netherlands), the SphygmoCor tonometer (AtCor Medical), the Colin blood pressure monitor (BMP)-7000 (Japan) - ejection duration (ED)	3 years	Blood pressure was measured using the Colin BPM 7000 on both arms (participants were seated). Next, a piezoelectric tonometer Colin BPM was placed over the radial artery for the acquisition of the radial arterial pressure waveform in a supine position. This signal was sent to the SphygmoCor and after averaging various parameters have been assessed and recorded: - ejection duration (ED) in milliseconds \[msec\]
Device: carotid intima-media thickness (IMT)	3 years	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).
Cardiovascular (CV)-related death recording during 2-year follow-up	2 years for each person qualified for the study	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.
Device: vessel stiffness assessments - peripheral (pPP) and central pulse pressure (cPP) [mm Hg]	3 years	The following parameters of vessel stiffness were assessed by Pulse Trace 2000 (Micro Medical Ltd., Rochester, Kent, United Kingdom): * peripheral pulse pressure (pPP) \[mm Hg\]; * central pulse pressure (cPP) \[mm Hg\]
Device: vessel stiffness assessments - reflection index (RI)	3 years	The following parameter of vessel stiffness was assessed by Pulse Trace 2000 (Micro Medical Ltd., Rochester, Kent, United Kingdom): - reflection index (RI) in percentages \[%\].

Trial Locations

Locations (1)

Poznan University of Medical Sciences; 🇵🇱 Poznań, Poland