Abstract

OBJECTIVE:

To study changes in the hemostatic balance during intranasal compared with oral administration of 17beta-estradiol (E2) and norethisterone (NET) or NET acetate in postmenopausal women. A wide range of markers of coagulation and fibrinolysis associated with coronary artery disease was tested.

DESIGN:

In a two-center, randomized, double-blind, comparative trial, 90 healthy postmenopausal women (aged 56.6 +/- 4.7 y) received daily continuous combined hormone therapy, either E2/NET 175 microg/275 mug intranasally as a spray (n = 47) or E2/NET acetate 1 mg/0.5 mg orally as a capsule (n = 43) for 1 year. Hemostatic markers were measured in blood samples taken at baseline and after 12, 24, and 52 weeks of treatment.

RESULTS:

After 52 weeks of treatment, changes in the intranasal group in markers of coagulation-fibrinogen (-1.3%), factor VII activity (-14.0%), and prothrombin fragment 1 + 2 (+5.8%)-were significantly less (P < 0.05) than the changes in the oral group for these parameters (-6.5%, -20.3%, and +19.0%, respectively). Changes in activated factor VII did not differ between the groups. Neither group showed significant changes in thrombin-antithrombin complex. In the intranasal group, decreases in markers of fibrinolysis-tissue-type plasminogen activator (-10.4%) and plasminogen activator inhibitor-1 antigen (-13.8%)-were significantly less (P < 0.05) than the decreases in the oral group (-17.8% and -38.0%, respectively). A decrease in plasminogen activator inhibitor-1 activity and increases in D-dimer and plasmin-alpha2-antiplasmin complex did not differ between the groups. No differences were found between the groups in homocysteine, which overall was unaltered in both groups.

CONCLUSIONS:

During intranasal E2/NET therapy, changes in the coagulatory and fibrinolytic markers were to some extent less than those observed during oral therapy.