Epidemiology of Venous Thrombosis and Pulmonary Embolism (LITE)

BACKGROUND:

Venous thromboembolism, comprising deep venous thrombosis (DVT) and pulmonary embolism (PE), is a major contributor to morbidity and mortality in the United States. Nevertheless, no comprehensive, prospective, population-based epidemiologic studies have simultaneously examined lifestyle, molecular, and biochemical risk factors for this important disease.

DESIGN NARRATIVE:

Deep venous thrombosis and pulmonary embolism cases were identified and verified in order to estimate incident rates of hospitalized venous thromboembolism in the combined ARIC and CHS cohorts. The association of venous thromboembolism was determined prospectively with demographic and lifestyle factors, plasma lipids, medical history, and hemostatic components (including fibrinogen, platelet count, factors VIIc and VIIIc) using existing ARIC and CHS data. A nested case control study was conducted using stored pre-diagnosis blood and DNA specimens to determine the prospective associations of venous thromboembolism with the following: levels of procoagulant or anticoagulant factors and related genetic variants (including factor V Leiden), fibrinolytic factors (e.g., plasminogen activator inhibitor-1) and related genetic variants, markers of thrombin activation, and other potentially important biochemical or related genetic factors (e.g., homocysteine).

The study was renewed in 2003 to extend event follow-up for four more years and to conduct longitudinal analyses of incidence and potential risk factors not fully explored such as diet, frailty, hormone replace therapy and obesity interactions. It was renewed in 2008 to conduct a genome wide association study.