The effects of oestrogen replacement therapy on haemostatic variables in postmenopausal women with non-insulin-dependent diabetes mellitus

Women with diabetes mellitus have an increased risk of developing coronary heart disease which may be related at least partially to unfavourable chang es in haemostasis. The effect of oestrogen replacement therapy on haemostas is has not been studied systematically in women with non-insulin-dependent diabetes mellitus (NIDDM) and therefore this study was performed for that p urpose. Twenty-five postmenopausal women with NIDDM were treated with 2 mg of 17-beta-oestradiol orally for 3 months in a double-blind, crossover, pla cebo-controlled trial. During the last 16 days of active treatment, 1 mg of norethisterone acetate was added for 10 days for endometrial protection. B lood samples were taken at baseline and after 68 days of active or placebo treatment. Treatment with oestradiol was followed by a marked decrease in t he activity of plasminogen activator inhibitor, compared with placebo. The activity of tissue plasminogen activator increased significantly. Levels of antithrombin decreased during treatment with oestradiol, whereas no change s were seen in levels of fibrinogen, von Willebrand factor, prothrombin fra gment 1+2, protein S, protein C or resistance to activated protein C. In co nclusion, oestrogen replacement therapy in postmenopausal women with NIDDM improved the fibrinolytic activity, while only clinically insignificant alt erations in the clotting system were seen. These changes in haemostasis may have a favourable impact on the risk for coronary heart disease in diabeti c women. (C) 1999 Lippincott Williams & Wilkins.