Age-related risks of long-term oral anticoagulant therapy.

Long-term oral anticoagulant therapy is critical to the optimal management of various thromboembolic and vascular disorders. To determine whether age is related to the development of bleeding complications in patients who are receiving long-term oral anticoagulant therapy, the records of 321 patients who were followed up in the university hospital outpatient anticoagulation clinic during an eight-year period were reviewed. During this period, 61 patients (19%) developed minor bleeding complications, and 14 patients (4.4%) developed major bleeding complications. In utilizing a life-table approach to adjust for varying lengths of follow-up, the risk of initial minor bleeding complications was found to be greatest within the first three months (14%). For major bleeding complications, risk increased throughout the first two years of anticoagulation clinic follow-up, with no particular period of greatest risk. No significant differences in the risk of initial minor or major bleeding complications were observed in the various age groups that were examined (less than 50, 50 to 59, 60 to 69, and greater than or equal to 70 years). A multivariate regression approach, controlling for several potentially confounding factors, confirmed the lack of an association of age with the risk of minor or major bleeding complications. The results of this retrospective follow-up study suggest that patient age, in and of itself, should not be considered a primary factor in assessing the risk of long-term oral anticoagulant therapy.