Review Article

Recurrent Venous Thromboembolism: What Is the Risk and How to Prevent It

Table 2

Factors that increase the risk of VKA-related bleeding.

(A) Treatment-associated factors
First 3 months of therapy
Target intensity of anticoagulation > 2.0–3.0 INR
Actual INR values > 4.5
Low quality of anticoagulation monitoring (high % time out of range)
Use of short half-life VKA drug
(B) Person-dependent factors
Advanced age (>75 years)
Frequent falls
History of major bleeding (especially in the GI tract)
History of atherosclerotic stroke
Uncontrolled hypertension
Cancer
Congestive heart failure
Anemia
Renal or liver failure
Alcohol abuse
Recent surgery
Associated antiplatelet therapy
Frequent use of NSAIDs
Polymorphisms of VKORC1 and CYP2C9
Mutation in factor IX propeptide (low factor IX levels)
Drugs affecting pharmacokinetics or pharmacodynamics of VKAs
Insufficient information and education to the treatment
Poor compliance
Poor dietary intake of vitamin K
Nutritional supplements and herbal products
Absence of familial or social support