The prevalence of risk factors for venous thromboembolism among hospital patients.

BACKGROUND: This study provides an estimate of the prevalence of risk factors for venous thromboembolism among hospital patients.

METHODS: The presence of risk factors for venous thromboembolism was determined from a retrospective review of the medical records of 1,000 randomly selected patients in 16 acute care hospitals in central Massachusetts.

RESULTS: The most common risk factors for venous thromboembolism were age 40 years (59%) or more, obesity (28%), and major surgery (23%). The average number of risk factors increased with increasing age. One or more risk factors for venous thromboembolism were present in 78% of hospital patients, two or more in 48%, three or more in 19%, four or more in 6%, and five or more in 1%.

CONCLUSION: Risk factors for venous thromboembolism are common among hospital patients, suggesting that prophylaxis should be widely employed. The cost-effectiveness and risk benefit of prophylaxis is well established in patients undergoing major surgery. Further studies are needed to confirm the benefit of prophylaxis in patients with nonsurgical risk factors for venous thromboembolism.