Effects of medroxyprogesterone acetate on some parameters of calcium metabolism in patients with glucocorticoid-induced osteoporosis

Clinical review: Do glucocorticosteroids alter vitamin D status? A systematic review with meta-analyses of observational studies

CONTEXT

Vitamin D supplementation is an important adjunct therapy for the prevention and management of glucocorticoid-induced osteoporosis. There has been little exploration of the relationship between glucocorticosteroid (GCS) use and serum 25-hydroxyvitamin D [25(OH)D].

OBJECTIVE

The aim of this study was to systematically explore how serum 25(OH)D is altered in adult patients receiving GCS.

DATA SOURCES

We reviewed Medline and Cinahl databases between January 1970 and August 2011.

STUDY SELECTION

Experimental studies were included where 25(OH)D was measured in patients more than 18 yr of age receiving GCS therapy. Studies were excluded if patients received at least 400 IU/d (10 μg/d) vitamin D, if GCS treatment was less than 2-wk duration, if more than 50% of the study population received GCS for renal or hepatic disease or after transplant, or if the study population included patients with Cushing's syndrome. A consensus method was used to classify studies. Of identified studies, 3% met the selection criteria.

DATA EXTRACTION

Data were extracted by a single author. Study quality was assessed using criteria developed by the American Dietetic Association.

DATA SYNTHESIS

The weighted mean 25(OH)D (by sample size or sd) was 22.4 [95% confidence interval (CI), 19.4, 25.3] ng/ml and 21.0 (95% CI, 13.5, 28.5) ng/ml, respectively. Random effects meta-analysis was used to compare serum 25(OH)D in patients treated with GCS compared to steroid-naive controls (either healthy or with active disease) and in patients before and after GCS administration. Serum 25(OH)D in GCS users was on average -0.5 (95% CI, -1.0, -0.1) ng/ml lower than in healthy controls (P=0.03; I2=56.4%). Serum 25(OH)D did not differ between GCS users and disease controls [standardized mean difference=0.0 (95% CI, -0.2, 0.3) ng/ml; P=0.793; I2=16.2%].

CONCLUSION

The suboptimal concentrations of serum 25(OH)D found in adults receiving GCS are inadequate for prevention and management of glucocorticoid-induced osteoporosis. Recommendations for vitamin D supplementation should be adjusted accordingly.

Premenopausal bone loss and depot medroxyprogesterone acetate administration

A 39-year-old woman on depot medroxyprogesterone acetate for 17 years developed multiple fractures after falling from a stationary horse. Densitometry revealed significant osteopenia. Although the reported patient was a thin, Caucasian woman, she did not have any other significant risk factors for osteoporosis except for a possible state of partial estrogen deficiency induced by the use of depot medroxyprogesterone acetate. Studies have shown that the estradiol levels of premenopausal women who have received this hormonal contraceptive for more than 1 year never reach those seen in the mid-cycle or luteal phase of the normal menstrual cycle. The estradiol levels are comparable only with those found in the early follicular phase. Therefore, women who use depot medroxyprogesterone acetate are in a state of partial estrogen deficiency, which may be associated with increased bone loss.

The anabolic effects of progesterone on fetal rat calvaria in tissue culture

OBJECTIVE

We examined the effects of progesterone and cortisol on [3H] thymidine incorporation into DNA, total DNA content, and [3H] proline incorporation into collagen using a bone organ culture system.

METHODS

The study consisted of nine experiments conducted at the University of Connecticut after approval by the animal care committee. Fetal rat half calvaria were cultured in the presence of progesterone (10(-5) to 10(-15) mol/L) and/or cortisol (10(-7) mol/L). Statistical analysis was carried out by analysis of variance.

RESULTS

There was a biphasic increase in [3H] thymidine incorporation and DNA content of the tissue sample with progesterone treatment, with peaks at both high and low concentrations. Significant increases in [3H] proline incorporation were noted at concentrations of 10(-6) to 10(-10) mol/L of progesterone. Similar responses were observed in the presence of cortisol.

CONCLUSIONS

Progesterone increased [3H] thymidine incorporation into DNA, total DNA content, and [3H] proline incorporation into collagen proteins in cultured fetal rat calvaria over a wide range of progesterone concentrations in the presence and absence of cortisol.

Effect of long-term administration of progestogen on post-menopausal bone loss: result of a two-year, controlled randomized study

OBJECTIVE

We determined whether a progestogen given alone to post-menopausal women may prevent bone loss.

STUDY DESIGN

Thirty-five early post-menopausal women who had not received any form of treatment to prevent bone loss were randomly assigned to a 2-year regimen of 500 micrograms/day of a gestagen derived from 19-norprogesterone (Promegestone) or a placebo for 21 days out of a 28-day treatment cycle. Bone mineral density of the spine was measured by dual photon absorptiometry.

RESULTS

After 2 years of treatment bone mineral density decreased significantly in the placebo group by a mean of 4.5%. In the gestagen group, the rate of bone change was significantly lower as compared to the placebo group (-1.3% +/- 1.2% vs -4.5% +/- 2% (mean +/- SEM), P < 0.05). There were no changes in the biochemical bone turnover parameters in the placebo group but in the gestagen group a significant decrease was observed in the urinary calcium excretion after 2 years.

CONCLUSION

The results suggest that a gestagen with no androgenic action can partly counteract early post-menopausal bone loss.