Risk Assessment by Cardiovascular Biomarkers in Chronic Dialysis Patients

Overview

Patients undergoing chronic dialysis are at a substantially increased risk of cardiac death. The reasons for this excess cardiovascular mortality are only partly understood. Classical complicated artherosclerotic disease does not appear to be the primary cause of cardiac death in chronic dialysis patients. In fact, the predictive potential of classic cardiovascular risk factors such as hypertension, obesity and hyperlipidemia appears to be reduced in dialysis. In contrast, in a series of pilot studies we found cardiac biomarkers to adequately reflect dialysis induced myocardial stunning, progressive cardiovascular disease, and the risk of death. To extend and corroborate these results, we are planning a large, prospective, observational study enrolling unselected hemo- and peritoneal dialysis patients. The proposed study, its power calculation and hypotheses are based on our pilot studies

Eligible patients will be identified through the clinical care team by undergoing chronic dialysis at one of the study centres. Dialysis patients will be initially approached during a routine dialysis session by a member of the clinical team to discuss the study and a participant information sheet will be provided. A minimum of 2 days after the provision of the participant information sheet, the clinical team will inform the research team about the patients who are interested in this study. Potential participants will be re-approached in person by a trained research physician to determine whether they are willing to participate in the study. If they are interested, the information sheet will be discussed with them and any questions will be answered. The investigators will explain the nature of the study, its purpose, the procedures involved, the expected duration, the potential risks and benefits and any discomfort it may entail to each potential participant. Each participant will be informed that the participation in the study is voluntary and that he/she may withdraw from the study at any time and that withdrawal of consent will not affect his/her subsequent medical assistance and treatment. All potential study participants will be provided with a participant information sheet and a consent form describing the study and providing sufficient information for the participant to make an informed decision about their participation in the study. The participant will be given a copy of the signed document. The consent form must also be signed and dated by the investigator (or his designee) and it will be retained as part of the study records. After consent is obtained, the participant will be allocated an unique study identification (ID) code. Patients are free to discontinue their participation in the study at any time, without having to give a reason for their withdrawal. Patient exposure will be censored for discontinuation of dialysis because of regaining renal function or patient's wish, study withdrawal and transfer of the patient to a non-participating dialysis unit. Patients undergoing renal transplantation during the observational period will not be censored, but will be reassessed 3 and 6 months after transplantation. First, written informed consent will be obtained from the patient. After we have obtained informed consent patients will undergo their standard three times weekly hemodialysis sessions or their daily peritoneal dialysis session. At the time of enrolment into the trial all patients will undergo a detailed clinical assessment including a medical history and a physical examination. At the beginning and the end of the dialysis session, at the time of the monthly routine blood tests additional venous blood samples will be collected. Serial assessments will be performed in 6 monthly intervals until the enrollment target has been met. After reaching the enrollment target the observational period will continue for another year.