Long-term effects of percutaneous estradiol on bone loss and bone metabolism in postmenopausal hysterectomized women

Assessment of estrogen exposure from transdermal estradiol gel therapy with a dried urine assay

Transdermal estradiol gel is a commonly used menopausal hormone therapy. In research studies investigating the pharmacokinetics and clinical utility of transdermal estradiol gels, serum is often used to measure estradiol levels. Serum results only represent a moment in time during phlebotomy and thus provide little information and allow for limited inference unless serial measurements are performed. In contrast, dried urine may provide a representation of serum estradiol levels over a longer period of time, while also being non-invasive and easier to collect. The primary aim of this study was to evaluate a dried urine method to determine if it may be a viable option for evaluating estrogen exposure resulting from transdermal estradiol gel use. A secondary aim was to explore differences in the urinary estrogen profiles of premenopausal women on no therapy and postmenopausal women who were either on transdermal estradiol gel therapy or no therapy at all. The results of this study demonstrated that the expected dose-proportional changes in estrogen exposure can be observed in the urinary estrogen profile using a GC-MS/MS dried urine assay. The GC-MS/MS assay also showed the differences in the urinary estrogen profiles of premenopausal women, postmenopausal women on estrogen replacement therapy, and postmenopausal women on no therapy.

Bone density and markers of bone remodeling in type 1 male diabetic patients

AIMS

To assess the prevalence and severity of bone disease in type 1 diabetic patients and to determine serum markers of bone remodeling as well as their relationship with bone mineral density (BMD).

METHODS

BMD [by dual energy x-ray absorptiometry (DXA)] and serum markers of bone remodeling [osteocalcin, c-terminal telopeptide of type I collagen (CTX)], leptin and osteoprotegerin (OPG) were measured in 42 adult males with type 1 diabetes. Twenty-four non-diabetic subjects served as controls.

RESULTS

In 40% of the patients, osteopenia at the lumbar spine (L1-L4) and/or at the left hip was found, and 7% met criteria for osteoporosis. L1-L4 BMD z-score was correlated with age (r=0.365, P=0.018) and a similar trend was observed at left hip. L1-L4 BMD z-score was negatively correlated with CTX and osteocalcin (r=-0.343, P=0.028; r=-0.376, P=0.024, respectively). A significant correlation was evidenced between BMD z-score at both lumbar spine and left hip and leptin values (r=0.343, P=0.03; r=0.395, P=0.012, respectively) but after adjustment for weight this correlation was no longer significant. Osteocalcin, CTX and leptin concentrations were comparable between patients and controls, while OPG concentrations tend to be higher in diabetic subjects (P=0.08). CTX was negatively correlated with age (r=-0.390, P=0.012) and positively correlated with osteocalcin (r=0.696, P<0.001). OPG was positively correlated with age (r=0.507, P=0.001).

CONCLUSION

Our results suggest that in diabetic subjects osteopenia is a relatively frequent complication but bone loss is attenuated with age progression. Whether this is also mediated by OPG and/or leptin remains to be confirmed.

Estradiol gel

OBJECTIVE

To review the pharmacology, pharmacokinetics, safety, and efficacy of a gel containing estradiol that is applied to the skin.

DESIGN

MEDLINE and EMBASE searches were conducted from 1966 to March 2005. Additional references were identified from bibliographies from selected studies in addition to approved product information.

RESULTS

Estradiol gel is indicated for the relief of moderate to severe vasomotor symptoms in menopausal women, and moderate to severe symptoms of vulvar and vaginal atrophy. Women who are intolerant of the oral route, have had previous hypersensitivity skin reactions, or have had difficulties with adhesive patches are ideal candidates for estradiol gel.

CONCLUSIONS

Estradiol gel can effectively reduce menopause symptoms with minimal side effects. Long-term safety data of estradiol gel are required.

Comparative endometrial histology in postmenopausal women with sequential hormone replacement therapy of estradiol and, either chlormadinone acetate or micronized progesterone

OBJECTIVES

To determine the endometrial response in postmenopausal women treated with a sequential hormone replacement therapy (HRT) of estradiol and, either chlormadinone acetate (CA) or micronized progesterone (MP).

METHODS

Three hundred and thirty-six postmenopausal women with a normal endometrium were randomized in the double-blind study. All patients received percutaneous estradiol 1.5 mg/day from day 1 to day 24 and either CA 10 mg/day or oral MP 200 mg/day from day 10 to day 24. The total duration of treatment was 18 months. Endometrial biopsies were performed before treatment and between day 18 and day 24 of the 18th month of HRT.

RESULTS

Of the 336 patients selected, 317 had a biopsy at inclusion. Of them, 244 patients (124 in the CA group and 120 in the P group) were suitable for evaluation for analysis at the 18th month. Insufficient sampling occurred in 33.9% in the CA group and 60% in the MP group (probably atrophic). No case of hyperplasia could be reported in both groups. The endometrium was atrophic in 19.5 versus 27.1%, proliferative in 3.7 versus 8.3% and secretory in 76.8 versus 62.5% in CA and MP groups, respectively. It was possible to see histological differences induced by the two progestins. The CA endometria showed fewer glands lined by a cubo-cylindrical epithelium, with an edematous stroma, compared to the MP endometria which had more glands lined by a cylindrical epithelium, stroma being poorly edematous. These figures varied in intensity due to the length of progestative impregnation, predecidualization occurring later in the CA group, with distended capillaries.

CONCLUSIONS

These results show that CA 10 mg/day is a powerful progestin compared to MP 200 mg/day, on weakly estradiol-primed endometria, giving a molecule-specific histological aspect with a good endometrial safety.

Transdermal delivery of drugs for the treatment of bone diseases

The current status of transdermal drug delivery for the treatment of bone diseases is described in this review. The structure, physiology and function of skin and their importance in determining delivery into and across skin are discussed. Special emphasis has been devoted to a description of the major pathways of transport across the skin and the quite continuing controversy over the importance of the transfollicular route. An overview of anatomic site-dependent drug absorption is also provided and is particularly relevant to determination of transdermal patch location. Brief descriptions of the criteria for selection of transdermal drug candidate, transdermal patch designs and currently marketed transdermal products are also included. Transdermal estradiol delivery systems are examined in more detail for their clinical and biological effects. Finally, the feasibility of delivering drugs such as bisphosphonates across skin is discussed.

Practical clinical application of biochemical markers of bone turnover: Consensus of an expert panel

Biochemical markers of bone turnover have emerged as powerful tools to aid in managing osteoporosis. The newer bone markers have been intensively studied for more than a decade. As a result, we can now confidently report their clinical utility in assessing risk of rapid bone loss and fracture, and monitoring therapy in postmenopausal women with or at risk of osteoporosis. In this review, we will provide a comprehensive foundation for this utility. While there are still questions remaining to be answered, bone marker technology has matured to play an essential role in patient management. We will describe, in practical terms, how bone markers can be appropriately incorporated into clinical practice today.