The effect of hormone replacement therapy on metabolism of lipoprotein remnants in postmenopausal women.
OBJECTIVE
The measurement of remnant-like particles reflects chylomicron and very low density lipoprotein remnants which are most likely atherogenic particles. We investigated the effects of menopausal status and postmenopausal hormone replacement on metabolism of remnant lipoprotein-cholesterol.


METHODS
We measured remnant lipoprotein-cholesterol by an immunoseparation assay in 20 premenopausal, 40 postmenopausal, and 30 bilaterally oophorectomized women. Of 70 postmenopausal subjects, 21 surgically menopausal women (with total hysterectomy) were started on hormone replacement with conjugated equine estrogen, 0.625 mg/day, and 36 naturally postmenopausal women were begun on a combination of conjugated equine estrogen 0.625 mg/day, plus medroxyprogesterone acetate, 2.5 mg/day. Plasma levels of remnant lipoprotein-cholesterol and other common lipids were measured after 6 and 12 months of treatment.


RESULTS
Plasma remnant lipoprotein-cholesterol levels in postmenopausal and surgically menopausal women were significantly higher than in premenopausal women (P < 0.005). Plasma total and low-density lipoprotein cholesterol levels decreased and high-density lipoprotein cholesterol increased significantly (P < 0.01) in both treatment groups, respectively. Plasma triglyceride levels were not changed by treatment; however, remnant lipoprotein-cholesterol levels decreased in both treatment groups (estrogen group; P = 0.07, estrogen-progestin group; P < 0.05). No side effects of therapy were consistently reported.


CONCLUSIONS
We confirmed that remnant lipoprotein-cholesterol increases after menopause. Hormone replacement therapy improves disordered lipoprotein metabolism and exerts a favorable effect on lipoprotein remnant metabolism in postmenopausal women.
Sanada
M
M
Department of Obstetrics and Gynecology, School of Medicine, Faculty of Medicine, Hiroshima University, Japan.
Nakagawa
H
H
Kodama
I
I
Sakasita
T
T
Ohama
K
K
D000328:Adult; D000368:Aged; D000704:Analysis of Variance; D001161:Arteriosclerosis / Q000517:prevention & control; D008076:Cholesterol, HDL / Q000097:blood*; D008078:Cholesterol, LDL / Q000097:blood*; D005260:Female; D020249:Hormone Replacement Therapy; D006801:Humans; D008875:Middle Aged; D010052:Ovariectomy; D017698:Postmenopause / Q000097:blood*; D014280:Triglycerides / Q000097:blood*
D008076:Cholesterol, HDL; D008078:Cholesterol, LDL; D014280:Triglycerides