Factor V Leiden has been reported to potentiate the thrombotic risk related with severe hyperhomocysteinemia, being more represented in thrombotic patients with homocystinuria as compared with patients without a history of thrombosis.
Our data also suggest that treatment of HCU not only reduces the thrombotic risk in patients with isolated HCU but also in those with the additional FVL heterozygosity.
Because patients with rare familial homocystinuria who also carry factor V Leiden have an increased incidence of venous thromboembolism (VTE), we hypothesized an interrelation of moderate hyperhomocyst(e)inemia, factor V Leiden, and risk of VTE in the general population.