Objective: To assess the effect of continuous combined hormone
replacement therapy (HRT) or tibolone on serum total homocysteine (tHcy)
levels in postmenopausal women. Study design: Ninety-five postmenopausal
women aged 41-68 years were included in the study. Seventy-three women
with climacteric complaints, osteopenia or osteoporosis received either
conjugated equine estrogens 0.625 mg combined with medroxyprogesterone
acetate 5 mg (CEE/MPA, n = 31) or tibolone 2.5 mg (n = 42). Twenty-two
healthy women, matched for chronological and menopausal age, served as
controls. Serum tHcy levels were assessed at baseline, 6, 12 and 18
months. Results: No difference was recorded between groups regarding
demographic characteristics or mean baseline serum tHcy. Serum tHcy
levels decreased significantly in the CEE/MPA compared to baseline
(change at 18 months: -3.9%, P < 0.05). The magnitude of the decrease
was higher in the subgroup of women with baseline tHcy levels above the
median (change at 18 months: -15.0%, P < 0.01). No change in tHcy
levels was detected in the tibolone group throughout the study period,
either in the whole group (change at 18 months: 1.9%, NS) or in the
subgroup with baseline tHcy levels above the median (change at 18
months: -3.23%, NS). Conclusion: Continuous CEE/MPA reduces tHcy
especially in women with high pretreatment tHcy levels. Tibolone has no
effect on serum tHcy levels at least during the first 18 months of
therapy. Larger studies with longer follow-up are required to confirm
these results. (C) 2003 Elsevier Ireland Ltd. All rights reserved