Risk factors of cerebral vein and sinus thrombosis

The risk factors for deep venous thrombosis (and for cerebral vein and sinus thrombosis, CVST) differ from those for arterial disease. The risk factors for venous thrombosis are linked to the Virchow triad of stasis of the blood, changes in the vessel wall, and changes in the composition of the blood, especially the first and third of these. Risk factors are usually divided into acquired (e.g. surgery, trauma, pregnancy, puerperium, lupus anticoagulant, malignant disease, and female hormones) and genetic (congenital thrombophilia). However, the separation of genetic and acquired risk factors is somewhat artificial, since they have additive effects and venous thrombosis is often multifactorial. In this review, we discuss acquired risk factors for CVST. These include hormonal changes (e.g. oral contraceptives use, hormone replacement therapy, pregnancy and puerperium), mechanical precipitants (e.g. head trauma, jugular catheterization, surgery, lumbar puncture), local and generalized infections, cancer, acquired prothrombotic states (e.g. hyperhomocysteinemia, nephrotic syndrome), inflammatory diseases (e.g. vaculitis, intestinal inflammatory disease), hematological disorders, neurological diseases (e.g. dural arteriovenous malformations, spontaneous intracranial hypotension), drugs and other situations. However, only some conditions are consistently present in case series, while many appear only in anecdotal reports. Thus, in most situations, a causal link cannot be established. Determining a cause-and-effect relationship is essential for developing preventive, diagnostic, and therapeutic strategies. Therefore, further multicentered, case-controlled studies are crucial for better understanding the pathogenesis of CVST.