[Optimizing history taking for evaluating the risk of venous thromboembolism: the OPTIMEV study].

Venous thromboembolism (VTE) is a frequent disease and remains a major cause of mortality and morbidity among our patients. During the 20 past years, clinical description, diagnostic tools, and treatment have changed dramatically. Most published data describing risk factors for VTE no longer apply to the patients seen in daily practice. We present here the rationale, aims, and methodology of the OPTIMEV Study (OPTimisation de l'Interrogatoire pour la Maladie thromboEmbolique Veineuse). RATIONALE: Risk factors for VTE are numerous, complex and interactions between them and their clinical importance is difficult to measure (table I). For example, odds ratios for VTE recurrence vary greatly across longitudinal studies. We searched the National Library of Medecine (PubMed) and the Amedeo website using the following keywords: "venous thromboembolism", "pulmonary embolism", "deep vein thrombosis", "risk factors". We selected 84 relevant articles published between 1972 and 2005. Based on this literature analysis, we identified the following major risk factors: VTE recurrence, surgery, cancer, immobilization, age, biological factors. For these factors, data are lacking and some questions are proposed. OBJECTIVES: The broad objective of the study is to better evaluate clinical risk factors that fit today's practice against VTE. Specific aims are: 1) to determine whether risk factors are different between proximal and distal deep vein thrombosis (DVT); 2) to develop and prospectively validate a new prediction rule for outpatients. The primary hypothesis is that careful assessment of VTE recurrence, adequate surgical thromboprophylaxis, cancer staging, and varicose vein stratification according to the CEAP classification, is mandatory for accurate evaluation of thromboembolic disease risk. METHODS: We conducted a multicenter, prospective, cohort study of 10000 patients. Enrollees are inpatients and outpatients presenting with a clinical suspicion of VTE in Emergency Departments and outpatient clinics in France. 4173 patients have been enrolled at this time (Figure 2). All eligible patients are enrolled during a selected period of time through different seasons. Data are collected by physicians in charge of the patients using an electronic case recording form. Collected data include baseline characteristics, risk factors, results of diagnostic investigations. Outcome measures obtained through telephone interview at 3 and 12 months include cancer diagnosis, VTE recurrence, haemorrhagic events, treatments, death. Univariate and multivariate analysis will be performed using multilevel logistic regression. The study organization is performed by the Centre d'Investigation Clinique de Grenoble and is sponsored by the French Society of Vascular Medicine. First results, to be published in 2006, will allow development of new prediction rules for VTE diagnosis.