Relationship between venous and arterial thrombosis: a review of the literature from a causal perspective.

Venous thrombosis and arterial thrombosis are traditionally regarded as two different diseases with respect to pathophysiology, epidemiology, and treatment strategies. Research findings of the past few years suggest that this categorical distinction may be too strict. However, whether the described relationship between venous and arterial thrombosis is real or a result of other factors such as confounding, chance, or bias is still unclear. In this review, we discuss the current literature while using causal diagrams to better understand possible causal relations between cardiovascular risk factors, atherosclerosis, arterial thrombosis, and venous thrombosis. Furthermore, we propose study designs to investigate the causal link between venous and arterial thrombosis. In addition, we comment on the effect of statin use on the occurrence of both arterial and venous thrombosis. The possible clinical implications of these findings are discussed.