Hormone replacement influences homocysteine levels in the methionine-loading test: a randomized placebo controlled trial in postmenopausal women

Objective: To investigate the mechanism by which exogenous oestrogen influences the homocysteine metabolism in postmenopausal women. Study design: A randomized placebo controlled trial in which a methionine-loading test was performed, in 25 healthy postmenopausal women, before and after a 12-week oral treatment with placebo or daily 4 mg 17ß-estradiol with (HRT) or without (ERT) 10 mg dydrogesterone. Fasting and post-load homocysteine as well as Vitamins B 6, B 12 and folate were determined. Results: In both treatment groups a significant 12% decrease in fasting homocysteine was observed. This decrease was accompanied by a post-load homocysteine increase of more than 20%. Vitamin B 6 values were decreased by more than 25%. Conclusion: The hormone therapy induced lowering of fasting homocysteine and Vitamin B 6 levels and an increase in post-load homocysteine, supporting the hypothesis that homocysteine–methionine metabolism is modulated by hormone therapy in postmenopausal women.