By Esben Bjøri, PhD student
Hospitalization is a well-known risk factor for venous thrombosis, but the risk of recurrence after hospital-related incidents is uncertain. Recently, we at K.G. Jebsen TREC may have shed some light on this matter.
In a recent study, we investigated the association between venous thrombosis that occur in relation to hospitalization and the risk of recurrent episodes. A major concern is namely that a large proportion of patients with venous thrombosis suffer from re-occurring episodes. To provide safe and effective prevention, it is essential to identify patients at high risk of recurrence, but at low risk of bleeding.
The study included 822 patients with a first episode of venous thrombosis. These were further stratified into 4 groups according to the characteristics of the first event: whether it was related to hospitalization for cancer, surgery or a medical condition, or not related to hospitalization at all. We then recorded recurrent events during follow-up. Importantly, these groups may differ with regards to the risk of dying, which may cause an overestimation of the risk-estimates in conventional analysis. To investigate the influence of death, we analyzed the data using both conventional and specialized analytical methods.
The results from our study revealed that patients suffering from a venous blood clot related to hospitalization for medical illnesses have a high risk of recurrence, independent of the mode of analysis. These results will need to be confirmed in future studies, but may have important treatment implications for these patients, as current guidelines recommend short over long-term treatment for these patients. However, our findings suggest that these patients may benefit from extended therapy aimed at preventing recurrent episodes.
Reference: Bjøri E, Arshad N, Johnsen HS, Hansen J-B, Brækkan SK. Hospital-related first venous thromboembolism and risk of recurrence. J Thromb Haemost 2016.