Epidemiology and socioeconomic consequences of venous thromboembolism
Venous thromboembolism (VTE) is a common disease with numerous well-characterized risk factors and many different clinical manifestations. There is great variation in the epidemiology and socioeconomic impact depending on the disease associations and the site of the thrombosis. The regional rates vary and in Western countries the incidence rate for first events is in the order of 100–250 per 100,000 person-years, attack rates (new and recurrent events) are about 250 per 100,000 person-years. The annual prevalence (a cross-sectional view) is about 400 per 100,000 population. Following hospitalization for medical or surgical conditions, the rates are higher and these events contribute to around half the population attributable risk. During periods of active cancer the incidence rates are very high. Post-thrombotic syndrome complicates 20–50% of deep vein thrombosis cases and is severe in 5–10%. Chronic thromboembolic pulmonary hypertension contributes significantly to the burden of VTE. Around 0.4–4% of patients with pulmonary embolism will eventually develop chronic thromboembolic pulmonary hypertension. Incidence rates for first episodes and attack rates have been widely studied, but incidence rates of recurrent events, post-thrombotic syndrome, and chronic thromboembolic pulmonary hypertension have not and generally only the cumulative incidence has been characterized. VTE mortality is significant particularly in the first 3 months, following that it is strongly related to the underlying diseases. The socioeconomic consequences of VTE are significant with respect to disability and costs.