Haemostatic and Lipid Abnormalities in Hypothyroidism

10 patients with hypothyroidism were examined before and 3 months after initiation of thyroxin treatment. All patients had high levels of plasma total cholesterol and total phospholipids, and 5 had an additional hypertriglyceridaemia. 1 patient had a prolonged primary bleeding time and all had a prolonged activated partial thromboplastin time and recalcification time in plasma. Platelet factor 3 activity in platelet rich plasma was reduced and total phospholipid and protein concentration in platelets were low. No significant correlation could be estiblished between the observed lipid, protein and haemostatic parameters, and it is suggested that they represent independent phenomena. All abnormalities were corrected by thyroxin replacement.