Risks with blood thinners rise with age

The risk of bleeding and thromboembolism (blood clots) in people who use anticoagulants increases with age. Anticoagulant medications such warfarin thin the blood and help prevent clots from forming or growing larger, thereby cutting the risk of heart attack and the type of stroke caused by artery blockages. Anticoagulant treatment in elderly patients presents a major clinical dilemma. While the risk of blood clots and the subsequent need for proper anticoagulant drug therapy increases sharply with age, the bleeding risk rises as well. Researchers from the Leiden University Medical Center in the Netherlands studied the risk of bleeding and embolism in roughly 4,200 patients who were treated with an oral anticoagulant between 1994 and 1998. Nearly 700 of them were more than 80 years of age. They found that the incidence of major bleeding increased sharply with advancing age. The oldest patients were 2.7 times more likely to experience a major bleeding event than the youngest patients. The risks of blood clots also increased with advancing age. The researchers suggest that older patients using anticoagulant medication may need more frequent monitoring by their doctor with a blood test called prothrombin time expressed as an INR. Doctors use this test to ensure that the dose of anticoagulant being given is not thinning the blood too much or too little.