Hemostasis and thyroid diseases revisited.

Several papers have reported various hemostatic abnormalities in patients with thyroid diseases. In this concise review, the traditional associations between hypercoagulable state and hyperthyroidism and between hypocoagulative state and hypothyroidism are critically revised on the basis of more recent literature data. In particular, we analyze the hemostatic balance (primary hemostasis, coagulation factors and fibrinolytic system) in different thyroid disorders. Although most of the studies published so far include limited numbers of patients and their results are sometimes contradictory, we can conclude that hyperthyroidism is generally accompanied by a hypercoagulable state, whereas the hemostatic profile in hypothyroidism and thyroid cancer depends on the severity of the disease.