Insights into the cause of kidney failure have emerged from research, but less is known about the epidemiology of less severe forms of kidney disease known both as chronic kidney disease (CKD) or chronic renal insufficiency (CRI). The Chronic Renal Insufficiency Cohort (CRIC) Study was established to study the consequences of CKD with a particular focus on cardiovascular illness like myocardial infarction (heart attack) and stroke. The CRIC Study will identify high-risk subgroups of individuals with CRI, informing future treatment trials, and development of preventive therapies. CRIC is an observational study that to date, 3612 participants have been enrolled in the CRIC cohort. The goal for Phase III is to enroll 1500 new participants across all seven Clinical centers (214 new participants per center). Participants previously enrolled will be followed for an additional 5 years and newly recruited participants will be followed for up to an additional 5 years. Principles underlying the targeted composition of the cohort of new recruits are very similar as the Phase I recruits, however with some modifications as listed below in the eligibility summary. No study treatments or interventions will be given to participants in CRIC. Subjects will include a racially and ethnically diverse group of adults aged 45 to 79 years old with a broad spectrum of renal disease severity and proteinuria levels. Participants who are 65 years or older will undergo additional testing to assess physical and cognitive function, social support, and quality of life.
Eligible men and women who consent will be enrolled in this observational study. Participants will remain under the care of their usual physicians. Questionnaires will be completed and tests will be conducted that will provide information about aspects of kidney and heart health status.
Participants are screened over the course of a brief visit during which informed consent is obtained, height and weight measured, blood drawn and a few forms are completed.
If eligible, a participant will return to the center for a more extensive visit. At the Baseline Visit the following will occur:
- eligibility is confirmed
- weight, height, waist and body water and fat content are measured by Bioelectrical Impedance Analysis (BIA)
- blood pressure and heart rate are recorded
- information about medical history and medication used recently
- blood draw (about ½ cup) for the following tests: CBC (Complete Blood Count), tests of metabolism, and several other heart and kidney tests
- blood pressure in the leg and arm calculated as the Ankle Brachial Index (ABI)
- Electrocardiogram (ECG)
- urine sample and collection of 24-hour urine sample for kidney function testing
- complete questionnaires about quality of life, diet, mood, thought processes and physical activity
- nail clipping
This visit takes about 3 to 4 hours. Participants will be contacted by telephone six months after the Baseline Visit to ask about recent medical events and medications.
Participants will be asked to return to the center for annual visits during which many but not all of the procedures described above will be conducted.