Clinical trial NCT00868712: Warfarin and Coronary Calcification Project
Official title: Warfarin and Coronary Calcification Project
Study type: OBSERVATIONAL
Overall status: COMPLETED
Conditions: Coronary Calcification
Keywords: coronary calcification
vitamin K dependent proteins
warfarin
Lead sponsor: Walter Reed Army Medical Center
Sponsor class: FED
First posted: 2009-03-25
Enrollment: 70
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Observational model: COHORT
Time perspective: PROSPECTIVE
Sampling method: NON_PROBABILITY_SAMPLE
Study population: Patients without known coronary heart disease, disorders of calcium metabolism or chronic kidney disease aged \> 18 years who are referred to take or currently taking warfarin and are followed in the Anticoagulation Management Clinic at Walter Reed Army Medical Center (WRAMC).

Brief summary: The purpose of the study is to assess whether the use of warfarin, a commonly used anticoagulation drug, is associated with increased amounts of coronary artery calcification. Studies in animals and preliminary but small retrospective studies in humans have suggested a possible link to increased tissue calcification with use of this drug. The researchers will investigate this by assessing the amount of calcification seen in the coronary arteries using a specialized computed tomography (CT) scan (electron-beam CT) and assessing to see if the amount is influenced by the amount of time a patient has been taking warfarin. The researchers will exclude patients with known coronary artery disease, chronic kidney disease or hyperparathyroidism.


Eligibility criteria: Inclusion Criteria:

* Age 18 years of age or older
* Patients referred to begin or already treated with warfarin anticoagulation therapy.

Exclusion Criteria:

* Known prior myocardial infarction or coronary heart disease
* History of advanced chronic kidney disease manifested by serum creatinine\>2 or calculated glomerular filtration rate (GFR)\<30
* History of hyperparathyroidism
* Current hypercalcemia
* Current hyperphosphatemia
* Uncertain duration of warfarin therapy
* Lack of records documenting international normalized ratio (INR) during therapy

Primary outcomes:
measure: Coronary Calcification (Presence and Degree as Measured by Agatston Score) Attributed to Duration of Warfarin Use in Months After Controlling for Standard Cardiovascular Risk Factors to Include the Framingham Risk Score
timeFrame: EBCT scan is done at time of enrollment of patient into 1 of 3 groups based on warfarin use duration: <6 months; 6-24 months; >24 mos.
Secondary outcomes:
measure: International Normalized Ratio
timeFrame: EBCT scan is done at time of enrollment of patient into 1 of 3 groups based on warfarin use duration: <6 months; 6-24 months; >24 mos.
Other outcomes:
Locations:
city: Washington
country: United States
facility: Walter Reed Army Medical Center
state: District of Columbia
Study officials:
References:
citation: Villines TC, O'Malley PG, Feuerstein IM, Thomas S, Taylor AJ. Does prolonged warfarin exposure potentiate coronary calcification in humans? Results of the warfarin and coronary calcification study. Calcif Tissue Int. 2009 Dec;85(6):494-500. doi: 10.1007/s00223-009-9300-4. Epub 2009 Oct 22.