The aims of the presented study are as follows:

1. To evaluate the endothelial function and arterial stiffness in a large cohort of prevalent CKD patients by means of non-invasive applantion tonometry.
2. To evaluate the association between the serum levels of the representatives of the various classes of uremic toxins and markers of endothelial function and arterial stiffness.
3. To evaluate the association between markers of inflammation and oxidative stress and markers of endothelial function and arterial stiffness.
4. To evaluate the association between echocardiographic parameters and markers of arterial stiffness

Inclusion Criteria:

• Age: 18-60
• Chronic kidney disease: according to the K-DOQI guidelines ( kidney damage ≥ three months, as defined by structural or functional abnormalities of the kidney, with or without decreased GFR, manifest by either: pathological abnormalities; or markers of kidney damage, including damage in the composition of blood or urine test, or abnormalities in imaging tests; GFR< 60 ml/min/1.73m² for ≥ three months, with or without kidney damage)
• Written informed consent

Exclusion Criteria:

• major illnesses( life expectancy of < 1 year)
• history of atrial fibrillation
• history of myocardial infarction, unstable angina, congestive heart failure, peripheral vascular diasease ,cerebrovascular disease, diabetes

(nonechogenic)

CKD patients