Predicting the risk of recurrent venous thrombosis: What the future might bring

An important clinical problem in the management of venous thrombosis is to determine whether a patient can safely cease anticoagulant therapy. In this Forum article, we summarize the predictive performance of several prediction models for recurrent thrombosis, as well as for bleeding while using anticoagulants. Patients with provoked first thrombosis (considered "low risk") are now denied long-term treatment, although a strong gradient in risk can be found in this group. We furthermore discuss the problem of an unclear definition of "(un)provoked" and show that this affects the yield of currently available prediction scores plus the limitations of a "one-size-fits-all" strategy. Better prediction tools are urgently needed. We propose a strategy for future studies for which the following should be considered: (a) reporting of absolute risks next to C-statistics, (b) model applicable to all patients, (c) no discontinuation of anticoagulation for measurement of predictors.