A 2-year study of lipid and lipoprotein changes in postmenopausal women with tibolone and estrogen-progestin.
OBJECTIVE
To assess changes in lipid-lipoprotein profile in postmenopausal women taking tibolone and estrogen-progestin, compared with untreated controls.


METHODS
Sixty-three women were randomized to take a combined estrogen-progestin preparation (n = 31) or tibolone (n = 32), and 50 other women acted as controls. Fasting lipid-lipoprotein levels were measured over 96 weeks.


RESULTS
The controls, who were older and postmenopausal longer than the therapy subjects, exhibited significant decreases in total (P < .05) and low-density lipoprotein (LDL) (P < .001) cholesterol and increases in triglyceride (P < .05) and lipoprotein (a) (P < .001) over the 96-week period of study. Lipoprotein (a) also decreased significantly in both treated groups (P < .001). Total and LDL cholesterol decreased and triglyceride increased in the estrogen-progestin group, but, compared with controls, these changes were not significant. Total cholesterol decreased in the tibolone group, although decreases in low- and particularly high-density lipoprotein (HDL) (P < .001) cholesterol and parallel decreases in apolipoprotein A1 (P < .001) and B (p < .01) were also observed. There was evidence of a reversion phenomenon in apolipoproteins A1 and B in all groups, and in lipoprotein (a) with tibolone.


CONCLUSIONS
Some changes accompanying tibolone may be favorable and may counter its adverse effect on HDL cholesterol. Lowering of lipoprotein (a) was the only significant change found with estrogen-progestin.
Milner
M H
MH
Department of Obstetrics and Gynaecology, Royal College of Surgeons in Ireland, Dublin.
Sinnott
M M
MM
Cooke
T M
TM
Kelly
A
A
McGill
T
T
Harrison
R F
RF
D000818:Animals; D016632:Apolipoprotein A-I / Q000097:blood; D001055:Apolipoproteins B / Q000097:blood; D008076:Cholesterol, HDL / Q000097:blood; D008078:Cholesterol, LDL / Q000097:blood; D015914:Estrogen Replacement Therapy; D004966:Estrogens, Conjugated (USP) / Q000008:administration & dosage* / Q000009:adverse effects / Q000494:pharmacology; D005260:Female; D006801:Humans; D008055:Lipids / Q000097:blood*; D008074:Lipoproteins / Q000097:blood*; D051379:Mice; D008875:Middle Aged; D009644:Norgestrel / Q000008:administration & dosage* / Q000009:adverse effects / Q000494:pharmacology; D009652:Norpregnenes / Q000009:adverse effects / Q000494:pharmacology*; D014280:Triglycerides / Q000097:blood
D016632:Apolipoprotein A-I; D001055:Apolipoproteins B; D008076:Cholesterol, HDL; D008078:Cholesterol, LDL; D004966:Estrogens, Conjugated (USP); D008055:Lipids; D008074:Lipoproteins; D009652:Norpregnenes; D014280:Triglycerides; D009644:Norgestrel; C027385:tibolone