Increased factor VIII associated activities in Cushing's syndrome: a probable hypercoagulable state.

Thirteen women and 2 men affected by Cushing's syndrome were investigated. The following parameters were used: plasma and urinary cortisol levels, factor VIII assay (antigen, activity and von Willebrand factor) together with other coagulative assays. Samples were taken before surgery or before medical and/or radiation therapy and every 30-50 days after treatment and continued for 11 months. Cortisol and factor VIII were increased before treatment and decreased slowly after treatment to become normal in 3-4 months. Other clotting tests did not show significant changes. It seems that high plasma cortisol levels may stimulate the production of factor VIII. Patients with Cushing's syndrome often exhibit thromboembolic complications after surgery. It is likely that the clotting abnormalities responsible for such complications is the increased factor VIII activities level.