Clopidogrel Prevention of Early Arteriovenous (AV) Fistula Thrombosis

• Clopidogrel (Drug)
• Placebo (Drug)

Primary outcomes

• Fistula thrombosis (patency failure) [6 weeks]: The fistula was classified as patent if a bruit was audible with a stethoscope throughout systole and diastole at least 8 cm proximal to the arteriovenous anastomosis. Fistula patency was assessed by trained study personnel.

Secondary outcomes

• Failure to attain suitability for dialysis (ability to use the fistula for dialysis with 2 needles and maintain a dialysis machine blood flow rate adequate for optimal dialysis (>=300 mL/min)) [30 days]: Fistula suitability was defined as the ability to use the fistula for dialysis with 2 needles and maintain a dialysis machine blood flow rate adequate for optimal dialysis (>=300 mL/min) during 8 of 12 dialysis sessions occurring during a 30-day suitability ascertainment period. For participants receiving maintenance hemodialysis at the time of enrollment and for participants who started maintenance hemodialysis within 120 days after fistula creation, the suitability ascertainment period began between 120 and 150 days after fistula creation surgery.

Sex: All, ages: 18 Years to any

Fistula Study Protocol

Inclusion Criteria:

* Age 18-21 depending on state regulations
* Life expectancy of at least six months
* Chronic renal failure with anticipated start of hemodialysis within six months of enrollment, or current dialysis dependence
* Planned creation of native upper extremity AV fistula
* The patient is not on aspirin, or the patient is on aspirin but has not had a myocardial infarction or a cerebrovascular accident within the past 12 months.
* The patient is expected to stay at a participating dialysis facility for at least 6 months.
* The patient's physician(s) will allow the patient to participate.
* Ability to give informed consent.

Exclusion Criteria:

* Women must not be pregnant, breastfeeding, or plan to be pregnant during the course of the study.
* The presence of ongoing bleeding.
* The presence of a known bleeding disorder (e.g., hemophilia or von Willebrand's disease).
* Recent bleeding episode requiring transfusion within 12 weeks of entry.
* The presence of acute ulcer disease. Acute ulcer disease is defined as a new diagnosis of peptic disease including esophagitis, gastritis, or ulcer or the initiation of treatment with proton pump inhibitors, H2 blockers or therapy for Helicobacter pylori within three months prior to obtaining consent.
* A condition which prohibits discontinuation of anticoagulant drugs, aspirin, or nonsteroidal anti-inflammatory drugs during the six week study drug administration period. Use of heparin during dialysis is allowed.
* Required use of oral or intravenous glucocorticoids at a dose greater than the equivalent of prednisone 15 mg per day during the six week study drug administration period.
* Current unstable angina.
* Required use of clopidogrel.
* Known hypersensitivity to clopidogrel.
* Medical considerations making anti-platelet therapy dangerous.
* Current uncontrolled hypertension with systolic blood pressure in excess of 200 mm Hg or diastolic blood pressure in excess of 115 mm Hg at the time of enrollment.
* Baseline platelet count less than 75,000/mm3.
* Known advanced liver disease with decompensated cirrhosis, jaundice, ascites or bleeding varices.
* Current problem with substance abuse.
* Concurrent participation in another medical intervention trial.
* Anticipated non-compliance with medical care based on physician judgment.
* Patient refusal.

• Dember LM, Kaufman JS, Beck GJ, Dixon BS, Gassman JJ, Greene T, Himmelfarb J, Hunsicker LG, Kusek JW, Lawson JH, Middleton JP, Radeva M, Schwab SJ, Whiting JF, Feldman HI; DAC Study Group. Design of the Dialysis Access Consortium (DAC) Clopidogrel Prevention of Early AV Fistula Thrombosis Trial. Clin Trials. 2005;2(5):413-22. doi: 10.1191/1740774505cn118oa. PMID 16317810
• Results publication: Dember LM, Beck GJ, Allon M, Delmez JA, Dixon BS, Greenberg A, Himmelfarb J, Vazquez MA, Gassman JJ, Greene T, Radeva MK, Braden GL, Ikizler TA, Rocco MV, Davidson IJ, Kaufman JS, Meyers CM, Kusek JW, Feldman HI; Dialysis Access Consortium Study Group. Effect of clopidogrel on early failure of arteriovenous fistulas for hemodialysis: a randomized controlled trial. JAMA. 2008 May 14;299(18):2164-71. doi: 10.1001/jama.299.18.2164. PMID 18477783
• Results publication: Natale P, Palmer SC, Saglimbene VM, Ruospo M, Razavian M, Craig JC, Jardine MJ, Webster AC, Strippoli GF. Antiplatelet agents for chronic kidney disease. Cochrane Database Syst Rev. 2022 Feb 28;2(2):CD008834. doi: 10.1002/14651858.CD008834.pub4. PMID 35224730

• John W Kusek, Ph.D., Study director, NIDDK - Telephone: 301-594-7717; Email: kusekj@ep.niddk.nih.gov
• Catherine Meyers, M.D., Study director, NIDDK - Telephone: 301-451-4901; Email: meyersc@extra.niddk.nih.gov

NIH grants: U01DK058982