The effect of various hormonal preparations and calcium supplementation on bone mass in early menopause. Is there a predictive value for the initial bone density and body weight?

Objectives. To compare the effect of various oestrogen and oestrogen/progestin preparations on bone density over a 2-year follow-up period in early postmenopausal women. Setting. A retrospective study on 315 women followed in a menopause clinic. Design. Antero-posterior lumbar spine bone densitometry was performed at baseline and between 18 and 24 months (mean 22 months) after initiation of hormone therapy. Participants were divided into six groups: women taking conjugated equine oestrogen (CEE) (n = 30); CEE plus sequential monthly medroxyprogesterone acetate (MPA) (n = 52); CEE plus sequential bimonthly MPA (n = 51); oral estradiol plus sequential monthly norethisterone acetate (n = 52); transdermal estradiol plus sequential monthly MPA (n = 30). A control group (n = 100) was composed of nonusers of hormones. Results. Hormone users, as a whole (n = 215), increased their bone mineral density (BMD) by 2.9% (4.8) as compared to the controls who lost 3.5% (3.4; P < 0.001). There were similar gains in BMD amongst the five study groups. Calcium supplementation was associated with better results in all women: users of hormones and calcium had a gain in BMD of 4.5% (4.8) compared to only 1.5% (4.5) in those on hormones but without calcium (P < 0.001); amongst the controls, women using calcium lost 1.4% (2.4), whilst nonusers of calcium lost 3.7% (2.4; P < 0.001). A dose-response curve was found between basal BMD and the effect of hormone therapy: women with osteoporosis (T-score <75%) demonstrated the largest increase in BMD 6.3% (4.6), osteopenia (T-score 75-85%) was associated with a gain of 3.2% (5.6), low- borderline values (T-score 86,100%) gave a modest increase of 1.3% (4.3), and those with more than average BMD values (T-score >100%) actually lost bone despite hormone treatment [-2.1% (4.1)]. Conclusions. All hormone regimens had a similar bone conserving effect. Basal BMD value-may serve as a predictor for the success of treatment. Calcium supplementation should be recommended in all postmenopausal women.