Rationale, design, and preliminary results of the Quebec Warfarin Cohort Study.

Over- and undercoagulation with warfarin are associated with hemorrhagic and thromboembolic events, respectively. Genetic and clinical factors affect warfarin response, and the causes of this variability remain unclear. We present descriptive statistics and test for predictors of poor anticoagulation control.

Nuclear receptor gene polymorphisms and warfarin dose requirements in the Quebec Warfarin Cohort.

Warfarin is primarily metabolized by cytochrome 2C9, encoded by gene CYP2C9. Here, we investigated whether variants in nuclear receptor genes which regulate the expression of CYP2C9 are associated with warfarin response. We used data from 906 warfarin users from the Quebec Warfarin Cohort (QWC) and tested the association of warfarin dose requirement at 3 months following the initiation of therapy in nine nuclear receptor genes: NR1I3, NR1I2, NR3C1, ESR1, GATA4, RXRA, VDR, CEBPA, and HNF4A.

Pillbox Use and INR Stability in a Prospective Cohort of New Warfarin Users.

Background: Warfarin, a frequently prescribed oral anticoagulant, is well known for its narrow therapeutic index. Adherence to warfarin may help to achieve a stable international normalized ratio (INR), but little data are available regarding the impact of using a pillbox as a potential adherence aid device.

Objective: To evaluate the association between pillbox use and time in therapeutic range (TTR) < 60% and INR instability pattern.

Avoidance of Vitamin K-Rich Foods Is Common among Warfarin Users and Translates into Lower Usual Vitamin K Intakes.

Background: Warfarin users should aim for stable daily vitamin K intakes. However, some studies report that patients are often advised to avoid eating green vegetables. Whether this advice impacts vitamin K intakes is unknown.

Impact of regular physical activity on weekly warfarin dose requirement.

Warfarin is an oral anticoagulant agent with a narrow therapeutic index. There is a marked inter- and intra-patient variability in warfarin dose requirement. All factors influencing warfarin response are not known and this study aims to evaluate if regular physical activity (RPA) is a determining factor.

Validation of patient-reported warfarin dose in a prospective incident cohort study.

Purpose: Inconsistencies in the definition and the collection of warfarin dosing data could lead to bias in observational, clinical, and pharmacogenetic studies. The present study aims to assess the concordance between patient-reported and prescribed warfarin doses among new warfarin users in the Quebec Warfarin Cohort (QWC) study.

Methods: Demographic, clinical, and lifestyle data were collected at cohort entry and each three months during a 1-year follow-up period among a subgroup of 219 patients from the prospective QWC study.

Adherence to antihypertensive agents after ischemic stroke and risk of cardiovascular outcomes.

Objective: To evaluate the relationship between antihypertensive (AH) drug adherence and cardiovascular (CV) outcomes among patients with a recent ischemic stroke and assess the validity of our approach.

Methods: A cohort of 14,227 patients diagnosed with an ischemic stroke was assembled from individuals 65 years and older who were treated with AH agents from 1999 to 2007 in Quebec, Canada. A nested case-control design was used to evaluate the occurrence of nonfatal major CV outcomes and mortality.

Extracellular Wound Matrices: Novel Stabilization and Sterilization Method for Collagen-based Biologic Wound Dressings.

Biologic extracellular matrix (ECM)-based wound dressings offer promise in the treatment of chronic wounds. A variety of animal and human tissue derived dressings are currently available. These products are processed and/or sterilized by a range of chemical and mechanical processes, which will impact the final quality of the matrices--ultimately affecting the overall wound healing process.