Age as a risk factor for venous thromboembolism after major surgery

PURPOSE OF REVIEW: Postoperative deep venous thrombosis and pulmonary embolism are serious and potentially life-threatening complications that frequently occur after major surgery. Most guidelines for thromboprophylaxis use advancing age as a key component to estimate thromboembolic risk. The reported effect of age on postoperative venous thromboembolism varies widely, making it unclear whether age alone is a significant risk factor. This article reviews the recent literature on the effect of age on the incidence of postoperative venous thromboembolism. RECENT FINDINGS: Between 2003 and 2005, several cohort studies assessed the risk factors for postoperative venous thromboembolism, showing a variable effect of age on its incidence in the 2- to 3-month period after major surgery. Studies also revealed a significant difference in the effect of age on the incidence of venous thromboembolism depending on the type of surgery. Obesity, postoperative immobilization, the use of thromboprophylaxis, the nature of the surgery, and underlying comorbid conditions such as heart failure seem to have a greater influence on the risk of venous thromboembolism than does age. SUMMARY: The variation in the effect of age on postoperative venous thromboembolism likely depends on whether or not other comorbid conditions or age-related changes in functional status are considered as risk factors. When these other risk factors are taken into account, the effect of advanced age decreases. More research is needed to develop validated venous thromboembolism risk-prediction tools for specific types of surgery. By use of this information, the intensity and duration of postoperative thromboprophylaxis can be tailored to the level of risk, not just age alone.