Jerome Burne and Bio-Identical Hormone Replacement Therapy: Parts 1 and 2 covered some difficulties with Kent Holtorf’s review article, Are Bioidentical Hormones (Estradiol, Estriol, and Progesterone) Safer or More Efficacious than Commonly Used Synthetic Versions in Hormone Replacement Therapy?, relating to a potential conflict of interest (despite a statement to the contrary) and the completeness and quality of the review. For this final examination of Jerome Burne’s Should middle-aged women be taking natural HRT?, we focus on a paper for which we had to guess the identity: Unequal risks for breast cancer associated with different hormone replacement therapies: results from the E3N cohort study. (Again, This Really Is Not Good Enough or TRINGE.) We should reiterate, as per parts 1 and 2, that this post is concerned with research standards and scholarship, not the relative merits or demerits of HRT and bioidentical hormone therapy.
Jerome Burne wrote:
When HRT was first developed, one of its key selling points was that it protected women against heart disease.
While studies have since proved that it does not have this protective effect, bio-identical versions might… The key is progesterone…
However, in the past 18 months there’s been new evidence from a French study to suggest that a bio-identical form of progesterone might also protect against breast cancer and heart attacks.
As above, HolfordWatch believes that Burne is referring to this large-scale epidemiological study: Unequal risks for breast cancer associated with different hormone replacement therapies: results from the E3N cohort study.
The authors of the E3N cohort study actually conclude:
E3N is the first epidemiological study that we know of to be providing results indicating that estrogen–progesterone and estrogen–dydrogesterone combinations may be the least harmful estrogen–progestagen HRTs regarding breast cancer risk. However, more evidence is required before these results can be translated into firm clinical recommendations for the management of menopausal symptoms. In addition, the effect of these combinations in other diseases (e.g., coronary heart disease, venous thromboembolism and colorectal cancer) has also to be evaluated. We therefore encourage further studies and reflection on the links between estrogen–progesterone and estrogen–dydrogesterone HRTs and breast cancer.
The short-hand version of this is that dydrogesterone is synthetic, a retroprogesterone and progestin – it is not a bio-identical hormone.
To be clear, a so-called bio-identical version of progesterone and a synthetic version both yielded better results than other varieties of progestagens for these outcomes in this study. The study authors sensibly call for more research to in order to make appropriate, evidenced clinical recommendations.
Burne then mentions that:
Some French researchers believe progesterone might also lower your risk of dementia. ‘Oestrogen and progesterone both have a protective effect on brain cells, unlike progestins,’ says Dr Michael Schumacher, of the Kremlin-Bicêtre hospital in Paris.
The support for that suggestion would seem to be this review:Novel perspectives for progesterone in HRT, with special reference to the nervous system. A substantial amount of the reported research on the brain or brain cells seems to be from animal studies:
In conclusion, a substantial number of animal studies have documented neuroprotective effects of progesterone or its reduced metabolites in the lesioned or diseased nervous system of young adult rodents.
It might seem a little premature to suggest that interesting animal studies might be extrapolated to imply similar neuroprotective effects in women and that is not readily apparent from the present article.
For women who may be interested in CAM offerings for menopause symptoms, AP Gaylard has a number of detailed explorations of red clover, black cohosh and other offerings (such as magnetic pads).
As ever, women who are considering hormonal or CAM interventions for menopause symptoms should consider their options in discussion with a GP or other appropriate health care worker.
And this concludes our present assessment of the state of the evidence and scholarship in Jerome Burne’s: Should middle-aged women be taking natural HRT?