ORAL ESTROGEN IMPROVES SERUM-LIPIDS, HOMOCYSTEINE AND FIBRINOLYSIS INELDERLY MEN

The effects of estrogen on cardiovascular risk factors have been less well defined in men than in women. We measured lipid and lipoprotein c oncentrations, lipoprotein particle size distributions, lipoprotein (a ), homocysteine, and markers of thrombosis and fibrinolysis in 22 heal thy elderly men (age 74+/-3 years, mean +/-S.D.) before and after 9 we eks of treatment with 0.5, 1 or 2 mg/day of oral micronized 17 beta-es tradiol. LDL-C (-6%), apo B (-9%), triglyceride (-5%), and homocystein e (-11%) concentrations decreased with estradiol, whereas HDL-C (+/-14 %) increased. Intermediate-size VLDL subclass concentrations were lowe red and LDL and HDL subclass levels altered in such a way as to cause average LDL and HDL particle size to increase. Lipoprotein (a) did not change. Fibrinogen (-13%) and plasminogen activator inhibitor-1 (PAI- 1) concentrations (-26%) decreased, but there were no changes in throm botic markers including thrombin-antithrombin III complex, prothrombin fragment 1.2, D-dimer, antithrombin activity, protein-C and S and von Willebrand factor antigen. Breast tenderness occurred in four men and heartburn in five but did not require discontinuation of treatment. W e conclude that oral estrogen in men reduces homocysteine, fibrinogen, and PAI-1 concentrations and favorably influences VLDL, LDL and HDL s ubclass levels without increasing markers of thrombotic risk. (C) 1998 Elsevier Science Ireland Ltd. All rights reserved.