Vitamin K to Attenuate Coronary Artery Calcification in Hemodialysis Patients

Inhibit Progression of Coronary Artery Calcification With Vitamin K in HemoDialysis Patients: The iPACK-HD Study

The purpose of this study is to see if vitamin K supplementation three times per week reduces the progression of coronary artery calcification over 12 months in dialysis patients compared to placebo.

At every stage of chronic kidney disease (CKD), the leading cause of mortality is cardiovascular disease. This is due, in part, to vascular calcification (VC) of the coronary arteries. The extent of VC in the coronary arteries of patients with CKD is commonly determined by high resolution CT scan. The total coronary artery calcium (CAC) score, measured in Agatston units (AUs), reflects the calcium burden in the three major coronary arteries and is the current standard for determining extent of vascular calcification in hemodialysis patients. Matrix Gla protein (MGP), a vitamin K dependent protein, is a key inhibitor of vascular calcification and is present in the arterial wall. It is established that MGP becomes up-regulated adjacent to sites of calcification and that vitamin K is critical to its function. Therefore vitamin K status may be critical to the extent of vascular calcification in this patient group. However, to date, no trial has examined whether vitamin K supplementation prevents the progression of coronary artery calcification in patients with kidney failure, a group in which high risk has been established. Therefore, our primary research question is: Does vitamin K supplementation with 10 mg of phylloquinone thrice weekly reduce the progression of coronary artery calcification (as measured by CAC score) over 12 months in prevalent hemodialysis patients with a baseline CAC score of ≥ 30 Agatston Units compared to placebo?

Inclusion Criteria:

• Able to provide signed informed consent
• ≥18 years of age
• Expected to survive one year
• Have end-stage kidney disease and require hemodialysis
• Have a baseline coronary artery calcification score ≥30 Agatston units (AUs)

Exclusion Criteria:

• Have a medical condition that requires warfarin
• Require hemodialysis for acute kidney injury
• Are Pregnant
• Have other severe co-morbid conditions (e.g. malignancy, disabling stroke) with life expectancy less than one year
• Have undergone coronary artery bypass grafting or have stents placed in their coronary arteries
• Are currently enrolled in another interventional trial