Effects of Hormone Replacement Therapy on Serum Homocysteine and C-Reactive Protein Levels in Postmenopausal Women

Objective: Elevated levels of homocysteine (Hcy) and C-reactive protein (CRP) are each independently associated with increased risk for cardiovascular events in women. We investigated the effects of hormone therapy (HT) on serum Hcy and CRP levels in postmenopausal women. Materials and Methods: Postmenopausal women were treated with tibolone 2.5 mg daily (n=25), or with conjugated equine estrogens (CEE) 0.625 mg daily plus medroxyprogesterone acetate (MPA) 2.5 mg daily (n=24), or no treatment (controls, n=13). Blood samples were collected before therapy and after 6 months of therapy for serum homocysteine and C-reactive protein levels. Results: After 6 months of treatment, tibolone and CEE plus MPA did not cause significant changes in serum Hcy levels in postmenopausal women (p=0.29, p=0.68, respectively). The median CRP levels increased by 105.7% in CEE+MPA group (p=0.017). Tibolone did not have a significant effect on CRP levels (p=0.85). No significant variation in CRP and Hcy levels was observed in the control group. Conclusion: The both regimens are not likely to have a clinically relevant impact on serum Hcy levels in women with normal levels prior to therapy. HT does not seem to influence low-normal Hcy concentrations. The possible cardiovascular protective role of CEE+MPA is probably unrelated to its increasing effects on CRP levels in healthy postmenopausal women. Further studies are required to explore the clinical relevance of these observations.