Effects of oral and transdermal hormone replacement therapy on lipoprotein(A) and lipids: a randomized controlled trial.
OBJECTIVE
Our purpose was to compare the effect of oral and transdermal hormone replacement therapy on lipoprotein(a) and other plasma lipids in healthy postmenopausal women.


METHODS
A total of 120 postmenopausal women were enrolled in a prospective randomized controlled study, and allocated either to transdermal 17 beta-estradiol (50 micrograms/day) or to oral conjugated estrogen (0.625 mg/day). Forty-one age-matched women were used as the reference group. Plasma lipids and lipoproteins were determined every 3 months and differences were sought by statistical analysis.


RESULTS
Plasma lipoprotein(a) dropped after 3 months of treatment either with transdermal estradiol (p < 0.01) or oral estrogen (p < 0.01). Lipoprotein(a) was reduced by 12% and 22%, respectively. No further decreases were seen later on. Plasma total and low-density lipoprotein (LDL) cholesterol concentrations were decreased significantly with both treatments after 3 months of therapy. No difference was seen in the lowering effect on lipoprotein(a), LDL and total cholesterol concentrations between regimens. Plasma high-density lipoprotein (HDL) cholesterol and triglyceride concentrations increased throughout the study only in patients treated with oral estrogen.


CONCLUSIONS
These data demonstrate that hormone replacement therapy reduces the concentration of lipoprotein(a) when given both orally and transdermally. The lowering effect is achieved quickly because the maximal effect is observed after 3 months of therapy.
1st Department of Obstetrics and Gynecology, University of Milano, Italy.
M
M
Meschia
F
F
Bruschi
M
M
Soma
F
F
Amicarelli
R
R
Paoletti
P
P
Crosignani
D000279:Administration, Cutaneous; D000284:Administration, Oral; D002784:Cholesterol / Q000097:blood; D008076:Cholesterol, HDL / Q000097:blood; D008078:Cholesterol, LDL / Q000097:blood; D015914:Estrogen Replacement Therapy; D005260:Female; D006801:Humans; D008055:Lipids / Q000097:blood*; D017270:Lipoprotein(a) / Q000097:blood*; D008875:Middle Aged; D011446:Prospective Studies; D014280:Triglycerides / Q000097:blood
D008076:Cholesterol, HDL; D008078:Cholesterol, LDL; D008055:Lipids; D017270:Lipoprotein(a); D014280:Triglycerides; D002784:Cholesterol