Medline ® Abstracts for References 42-45

Bioidentical hormone therapy (BHT) uses bioidentical hormones (BHs), derivatives of plant extracts chemically modified to be structurally indistinguishable from human endogenous hormones. BHTs are available commercially or can be compounded into different dosages and for different routes of administration. Typically, compounded preparations of BHs may include estriol, estrone, estradiol, testosterone, micronized progesterone, and occasionally dehydroepiandrosterone (DHEA). It is generally accepted that estrogen-based hormone therapies share similar efficacies as well as risks. Many FDA-approved and regulated pharmaceutically manufactured and branded conventional hormone therapies (CHTs) employ BHs. Since the publication of the Women's Health Initiative (WHI) trial results publicizing an increased risk of stroke, venous thrombosis, and breast cancer and no beneficial effect on coronary heart disease (CHD), use of CHT has declined, and there has been increased interest in alternative approaches. This review of the literature related to compounded BHT and the practices of its advocates is to determine if sufficient scientific evidence supports claims of greater efficacy and safety and any additional risks and uncertainties not generally associated with CHTs. Compounded BHTs have been promoted by some as natural, safer, and in some cases more efficacious than conventional hormone therapies, but there is a dearth of scientific evidence to support these claims. Compounded BHTs lack well controlled studies examining route of administration, pharmacokinetics, safety, and a critical, science-based rationale for the mixture and ratios of bioidentical estrogens employed in many preparations. Many advocates of compounded BHTs customize prescriptions based on saliva tests or blood sera levels in direct contradiction to evidence-based guidelines, which support tailoring HT individually according to symptoms. Currently, scientific uncertainties associated with compounded BHTs make their use less preferable to that of CHTs, as CHTs have been and continue to be assessed by clinical trials regarding both benefits and risks and are indicated for use according to evidence-based guidelines.

OBJECTIVE: From a survey of compounding pharmacists, specific questions regarding compounded menopausal hormone therapy were used to estimate compounded hormone therapy (CHT) prescribing in the United States.

METHODS: A national online survey was conducted by Rose Research--a market research company consisting of 12,250 US pharmacists from independent community pharmacies (ICPs) and compounding pharmacies (CPs). Pharmacists who completed the survey and met the prespecified criteria were eligible. Data from the survey were extrapolated to estimate overall CHT prescription volume and annual costs of CHT prescriptions for the United States based upon industry data from the National Community Pharmacists Association and IBISWorld.

RESULTS: Surveys were completed by 483 pharmacies, including 365 ICPs and 118 CPs. On the basis of the survey responses and extrapolated industry data, an estimated 26 to 33 million CHT prescriptions were filled annually, with total sales estimated at $1.3 to $1.6 billion. CPs (vs ICPs) accounted for a higher proportion of CHT prescriptions. Morethan half of the ICPs (52%) and CPs (75%) expected continued compounding business growth, with most predicting 5% to 25% growth within 2 years, despite the potential effect of restrictive legislation regarding compounding.

CONCLUSIONS: On the basis of extrapolated data from numbers of prescriptions reported by pharmacists participating in the survey, the volume of CHT seems to approach that of Food and Drug Administration (FDA)-approved menopausal hormone therapy, and growth in the CHT market is expected. Thus, physicians should educate themselves and the women consulting them about the differences between the FDA-approved and the less-tested CHT formulations. More research on the efficacy, safety, and consistency of non-FDA-approved CHT is needed.

This Scientific Statement finds that there is no rationale for routine prescribing of unregulated, untested, and potentially harmful custom compounded bioidentical hormone therapies.