Epidemiology, risk factors and sequelae of venous thromboembolism.

The aim of this review was to discuss the epidemiology, risk factors and sequelae of venous thromboembolism (VTE). VTE has an incidence of 1-2 per 1000 people annually. The risk of VTE increases with age and is highest in Caucasians and African Americans. Combined oral contraceptives (COC), especially the third-generation COCs, have been strongly implicated in VTE. Hospitalized patients, especially patients with underlying malignancy and undergoing surgery, have a host of risk factors for VTE. Thrombophilia can predispose an individual to VTE but indiscriminate testing for thrombophilia in patients presenting with VTE is not indicated. VTE can have serious chronic sequelae in the form of post-thrombotic syndrome (PTS) and chronic thromboembolic pulmonary hypertension (CTPH). The risk of PTS and CTPH is increased with recurrent deep vein thrombosis and pulmonary embolism, respectively. Mortality from VTE can be as high as 21.6% at one year. Patients who had an episode of VTE have a high risk of subsequent VTE and this risk is highest in patients who had a first VTE event associated with malignancy. A good understanding of the epidemiology and risk factors of VTE will enable the treating medical practitioners to identify patients at risk and administer appropriate VTE prophylaxis to prevent the long-term consequences of VTE.